U.S. patent application number 15/594504 was filed with the patent office on 2017-08-31 for systems and methods for remote measurement of the eyes and delivering of sunglasses and eyeglasses.
This patent application is currently assigned to PERFECT VISION TECHNOLOGY (HK) LTD.. The applicant listed for this patent is PERFECT VISION TECHNOLOGY (HK) LTD.. Invention is credited to Junzhong Liang.
Application Number | 20170245758 15/594504 |
Document ID | / |
Family ID | 48135714 |
Filed Date | 2017-08-31 |
United States Patent
Application |
20170245758 |
Kind Code |
A1 |
Liang; Junzhong |
August 31, 2017 |
SYSTEMS AND METHODS FOR REMOTE MEASUREMENT OF THE EYES AND
DELIVERING OF SUNGLASSES AND EYEGLASSES
Abstract
The present disclosure provides methods, devices, and systems
for automated measured correction of the eyes and provision of
sunglasses and eyeglasses for individuals, including individuals
with a visual acuity of 20/20 or better. Methods, devices and
systems for remote measurement of refraction by an examiner away
from the measurement system are also disclosed.
Inventors: |
Liang; Junzhong; (Fremont,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PERFECT VISION TECHNOLOGY (HK) LTD. |
Tsuen Wan |
|
HK |
|
|
Assignee: |
PERFECT VISION TECHNOLOGY (HK)
LTD.
Tsuen Wan
HK
|
Family ID: |
48135714 |
Appl. No.: |
15/594504 |
Filed: |
May 12, 2017 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14646734 |
May 22, 2015 |
9649032 |
|
|
PCT/US13/71763 |
Nov 25, 2013 |
|
|
|
15594504 |
|
|
|
|
13687309 |
Nov 28, 2012 |
9277863 |
|
|
14646734 |
|
|
|
|
13116262 |
May 26, 2011 |
8419185 |
|
|
13687309 |
|
|
|
|
PCT/US09/66148 |
Nov 30, 2009 |
|
|
|
13116262 |
|
|
|
|
61200494 |
Dec 1, 2008 |
|
|
|
61208045 |
Feb 20, 2009 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G16H 10/60 20180101;
A61B 3/0033 20130101; G16H 30/20 20180101; G02C 7/02 20130101; G02C
13/003 20130101; A61B 3/0083 20130101; A61B 3/1015 20130101; A61B
3/036 20130101; A61B 3/0025 20130101; A61B 3/0285 20130101; A61B
3/0041 20130101; A61B 3/152 20130101; G02C 2202/22 20130101; G06F
19/321 20130101; A61B 3/18 20130101 |
International
Class: |
A61B 3/18 20060101
A61B003/18; A61B 3/00 20060101 A61B003/00; G02C 13/00 20060101
G02C013/00; A61B 3/10 20060101 A61B003/10; A61B 3/15 20060101
A61B003/15; A61B 3/036 20060101 A61B003/036; A61B 3/028 20060101
A61B003/028 |
Claims
1. A system for determining a spherical power of an eye for
prescription of eyeglasses, comprising: a data entry module capable
of obtaining a refractive data of an eye of a patient, wherein the
data entry module is configured for at least one of a) manually
importing the refractive data of the eye from a device, and b)
reading an electronic file that contains the refractive data;
wherein the refractive data includes a spherical power, and an
astigmatism having a cylinder power and a cylinder angle; an
astigmatism module with a plurality of cylindrical lenses for
refractive correction of astigmatism in an eye, wherein the
astigmatism module is configured such that manual and incremental
adjustment to the cylindrical power and cylindrical angle for the
combined lenses is excluded; a spherical module with a plurality of
spherical lenses for refractive correction of myopia, hyperopia and
presbyopia, wherein the spherical module is configured for
incremental adjustment to provide a plurality of focus powers for
each eye, wherein the plurality of cylindrical lenses are set
according to the cylinder power and the cylinder angle from the
refractive data before the plurality of spherical lenses are
adjusted for a subjective response; a controller coupled to the
spherical module and the astigmatism module, wherein the controller
is configured to enable manual and incremental adjustment of focus
power and to enable automatic adjustment of the astigmatism; a
manual control module for manual and incremental control of the
spherical module; and an output module configured to present a
refractive prescription in the form of printing, displaying, or
exporting, wherein the refractive prescription includes a spherical
power based on the subjective response for different settings of
the plurality of spherical lenses in the spherical module, and the
cylinder power and the cylinder angle imported from the data entry
module.
2. The system of claim 1 wherein the astigmatism module and the
spherical module are at an examination location, the system further
comprising: a module of remote control at a second location away
from the examination location, so that the system is controlled
through an electronic connection for at least one of a) remote data
entry, b) remote adjustment of the spherical module, and c) remote
voice or video communication between the patient at the examination
location and an examiner at the second location; wherein the module
of remote control comprises at least one of i) a data module for
data entry and transfer, ii) a module for voice communication
between the patient and the examiner, and iii) a video module for
real-time monitoring of a refraction process or for communication
between the patient and the examiner.
3. The system of claim 1 further comprising a camera system for
monitoring the relative position between the eye and an optical
axis of the system, the optical axis being the center of the lenses
in the spherical module and the astigmatism module.
4. The system of claim 1 further comprising a module for eye
positioning, the module for eye positioning comprising a head rest
and a motion-controlled system for positioning the head rest at a
plurality of positions.
5. The system of claim 1 further comprising a transportation system
for mobile operation.
6. The system of claim 1 wherein the refractive correction of
astigmatism varies continuously and has a resolution finer than
0.10D.
7. The system of claim 1 wherein the manual control module is
configured to be accessible to the patient for self-adjustment.
8. The system of claim 1, wherein an amount for incremental
adjusting of focus power is 0.25D or 0.125D, and wherein the focus
power can be increased or decreased.
9. The system of claim 1 wherein the data entry module is further
configured to receive the refractive data through an objective
refraction device.
10. The system of claim 9 wherein the objective refraction device
is a wavefront sensor for measuring all aberrations in the optics
of an eye, including spherical aberration.
11. The system of claim 10 wherein the refractive prescription
further includes the spherical aberration from the wavefront
sensor.
12. The system of claim 1 further comprising two independent
astigmatism modules and two independent spherical modules for
testing two eyes of the patient.
13. The system of claim 1 further comprising a prism module for
measurement of prism offsets between two eyes of the patient.
14. The system of claim 1 further comprising an input module
configured to accept payment information from the patient.
15. The system of claim 1 further comprising an input module
configured to accept delivery information from the patient.
16. The system of claim 1 further comprising an input module
configured to receive information about frames for eyeglasses or
sunglasses.
17. The system of claim 16 further comprising a camera to take a
picture of the patient with or without a selected frame.
18.-23. (canceled)
24. A refraction system for remote measurement of an eye,
comprising: a module for eye positioning, wherein the module for
eye positioning is motion-controlled and comprises a head rest, a
motion control system for positioning the head rest at a plurality
of positions, and a camera system for real-time monitoring of the
relative position between the eye and an optical axis of the
refraction system; an objective refraction device for measuring
refractive errors of the eye, wherein the refractive errors include
at least a cylinder power, a cylinder angle, and a spherical power;
a digital processor configured for controlling the module for eye
positioning and the objective refraction device; a display module
for the digital processor; a module of remote control for an
examiner to remotely control the digital processor away from and at
a different geographic location than the objective refraction
device, wherein the module of remote control is connected to the
refraction system through an electronic network, the module of
remote control comprising at least one of i) a data module for data
entry and transfer, ii) a module for voice communication between a
patient and an examiner, and iii) a video module for real-time
monitoring of the measuring of refractive errors or for
communication between the patient and an examiner; and an output
module configured to present a refractive prescription in the form
of printing, displaying, or exporting, wherein the refractive
prescription includes at least a focus power, a cylinder power and
a cylinder angle.
25. The refraction system of claim 24 further comprising an
interface configured to be coupled to a phoroptor for subjective
determination of a spherical power of the eye, comprising: an
astigmatism module with a plurality of cylindrical lenses for
refractive correction of astigmatism in the eye, wherein the
astigmatism module is configured such that manual and incremental
adjustment to the cylindrical lenses is excluded; a spherical
module with a plurality of spherical lenses for refractive
correction of myopia, hyperopia and presbyopia, wherein the
spherical lenses are configured to provide a plurality of focus
powers for each eye; and a controller coupled to the spherical
module, wherein the controller is configured to enable manual
adjustment of focus power by a specified amount.
26. The refraction system of claim 24 further comprising an input
module configured to accept payment information from the
patient.
27. The refraction system of claim 24 further comprising an input
module configured to accept delivery information from the
patient.
28. The refraction system of claim 24 further comprising an input
module configured to receive information of frames for eyeglasses
or sunglasses.
29. The refraction system of claim 24 further comprising a camera
configured to take a picture of the patient with or without a
selected frame.
30. A refraction system for remote measurement of an eye for
prescription of eyeglasses, comprising: a wavefront sensor module
for objective measurement of an eye's refractive errors,
comprising: a light source configured to produce a compact image at
a retina of an eye, wherein reflected light from the retina
generates an outgoing wavefront in front of a cornea of the eye
from a reflection of the retina; a wavefront sensor including a
wavefront sampling device and a digital image module for recording
images of the outgoing wavefront that passes through the wavefront
sampling device; a refraction correction module, comprising: an
astigmatism module with a plurality of cylindrical lenses for
refractive correction of astigmatism in the eye, wherein the
astigmatism module is configured such that manual and incremental
adjustment to the cylindrical lenses is excluded, and selection and
arrangement of cylindrical lenses are determined by the astigmatism
obtained from a digital computer and the wavefront sensor; a
spherical module with a plurality of spherical lenses for
refractive correction of myopia, hyperopia and presbyopia, wherein
the spherical lenses are configured to provide a plurality of focus
powers for each eye; a module for eye positioning, comprising a
head rest, a motion control system for positioning the head rest at
a plurality of positions, and a camera system for real-time
monitoring of the relative position between the eye and an optical
axis of the refraction system; a digital processor configured for
control of the refraction correction module, the module for eye
positioning, and the wavefront sensor module, wherein the digital
processor is also configured to take a sequence of wavefront
measurements at one time, including a) storing multiple wavefront
images into a memory unit, b) providing automatic detections of
sampling points of the wavefront sensor, c) calculating wavefront
slopes across a pupil of the eye, and d) determining a wave
aberration of the eye that includes at least a focus error, an
astigmatism, and a spherical aberration; a display module for the
digital processor; an output module configured to present a
refractive prescription in the form of printing, displaying, or
exporting, and a module of remote control for an examiner to
remotely control the digital processor away from and at a different
geographic location than the refraction correction module, wherein
the module of remote control is connected to the refraction
correction module through an electronic network, the module of
remote control comprising at least one of i) a data module for data
entry and transfer, ii) a module for voice communication between a
patient and an examiner, and iii) a video module for real-time
monitoring of the refraction process or for communication between
the patient and an examiner.
31. The refraction system of claim 30 further comprising a
controller coupled to the spherical module, wherein the controller
is configured to enable manual adjustment of focus power by a
specified amount.
32. The refraction system of claim 30 further comprising an input
module configured to accept payment information from the
patient.
33. The refraction system of claim 30 further comprising an input
module configured to accept delivery information from the
patient.
34. The refraction system of claim 30 further comprising an input
module configured to receive information of frames for eyeglasses
or sunglasses.
35. The refraction system of claim 30 further comprising a camera
configured to take a picture of the patient with or without a
selected frame.
36.-50. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 13/687,309 entitled "Methods and Systems for
Automated Measurement of the Eyes and Delivering of Sunglasses and
Eyeglasses" filed on Nov. 28, 2012; which is a continuation-in-part
of U.S. Patent Publication No. US2011/0228225 (U.S. Ser. No.
13/116,262) entitled "Methods and Devices for Refractive Correction
of the Eyes" filed May 26, 2011; which is a continuation of
International PCT Application No. PCT/US09/66148, filed Nov. 30,
2009; which claims the benefit of U.S. Provisional Patent
Application No. 61/200,494, filed Dec. 1, 2008 and the benefit of
U.S. Provisional Patent Application No. 61/208,045 filed Feb. 20,
2009; and all of which are incorporated herein by reference.
BACKGROUND
[0002] Refractive corrections for human eyes can be characterized
into two general categories. The first category is the conventional
method of vision correction which corrects for the eye's focus
error and cylindrical error as measured using a manifest
refraction. The second category is wavefront-guide vision
correction which provides correction for all aberrations in an eye,
including focus error, cylindrical error, spherical aberration,
coma, and others, measured using an objective wavefront sensor.
[0003] The conventional method of vision correction is conceptually
limited to a correction of just focus error and cylindrical error.
In addition, it is also constrained by the subjective nature of how
the manifest refraction determines the eye's refractive errors,
particularly the eye's cylindrical error. Cylindrical error is also
known as astigmatism, and it causes particular problems because it
includes both a cylindrical power and a cylindrical axis.
[0004] There are at least five limiting factors associated with a
manifest refraction. First, manifest refraction is limited by
available lenses in a phoroptor, because a manifest refraction
relies on applying corrective lenses and testing vision of the eye
subjectively. Focus error is usually limited to a resolution of
0.125 Diopters (D) while the cylindrical error is limited to a
resolution of 0.25 D. Second, subjective determination of
cylindrical axis can be problematic because a slight variation of
cylindrical axis--within only a few degrees--can cause a
significant performance difference for a cylindrical correction of
more than 2 D. Third, human errors by either the patient or a
practitioner--such as an optometrist or optician--cannot be
excluded because a manifest refraction involves the subjective
responses of a patient to a plurality of refractive corrections, as
well as the practitioner's analysis of those subjective responses.
Fourth, a manifest refraction is fundamentally a partial empirical
refractive solution, because a practitioner conducting the manifest
refraction determines an end point for a refractive correction in a
time-consuming process. Finally, manifest refraction can also be a
time consuming process because it relies on human control of vision
optimization with as many as three independent variables which
include a focus error, a cylindrical power, and a cylindrical
axis.
[0005] The drawbacks associated with using a manifest refraction
compound with the high tolerance of current lens manufacturing
techniques and lead to widespread erroneous vision correction. The
inaccuracy of the conventional vision correction method using a
manifest refraction leads to a situation where there may be
significant differences in a refractive prescription of the same
eye by different practitioners, as well as in a coarse resolution
of cylindrical power--as large as 0.25 D--universally prescribed
for conventional vision correction. Consequently, available
ophthalmic lenses in today's ophthalmic industry are also limited
to lenses in 0.25 D resolution. Correcting an eye's astigmatism
using conventional vision correction is further complicated by the
high tolerance in fabricating conventional spectacle lenses.
Moreover, it is accepted in the industry that visual acuity of
20/20 is perfect already with no need for correction.
SUMMARY
[0006] In one aspect of the invention, an automated method for
determining a refractive correction of an eye is provided.
[0007] Thus, certain embodiments of the present invention provide
methods for providing a pair of sunglasses to an individual,
including individuals with a visual acuity of 20/20 or better,
comprising the steps of: 1) providing a measuring station
configured for automatic data acquisition without necessary
intervention from a human other than the individual, the measuring
station configured to obtain an objective measurement of wave
aberration from each eye of the individual; place a plurality of
lenses according to the obtained an objective measurement of wave
aberrations into a correction module for the individual to see
through and to read at least one acuity chart; and determine a
focus power of each eye through subjective refraction, wherein the
subjective refraction involves subjective responses from the
individual to a plurality of focus powers; 2) generating correction
data for making the pair of sunglasses; 3) transmitting data for
making the pair of sunglasses via an electronic media, wherein the
transmitted data contains at least the correction data for making
the pair of sunglasses; 4) manufacturing lenses for the sunglasses
based on the correction data; 5) fitting the lenses into frames to
produce finished sunglasses; and 6) providing the finished pair of
sunglasses to the individual.
[0008] In some aspects of this embodiment, the pair of sunglasses
provided is an over-the-counter pair of sunglasses that does not
require a prescription. In some aspects, the measuring station
further is configured to accept results from the individual in
reading the acuity chart through the correction module for each
eye, and in some aspects the measuring station further is
configured to allow the individual to manually adjust the focus
power of the correction device. In some aspects, the transmitting
data step for making the pair of sunglasses further includes at
least one of following for reviewing and checking by a human other
than the individual: a) records for the obtained an objective
measurement of wave aberration from each eye of the individual, b)
results of the individual in reading the acuity chart through the
correction device for a plurality of focus powers.
[0009] In some aspects of this embodiment of the invention, the
measuring station further is configured to determine a measured
cylindrical power and cylindrical axis from the objective
measurement of wave aberration. In some aspects, the measuring
station further is configured to offer to and receive from the
individual a selection of sunglass frames. In some aspects, the
generated correction data for lenses is modified to take into
account of the shape of selected sunglass frames, and in some
aspects, the measuring station further is configured to take a
picture of the individual with and/or without the selected pair of
sunglasses.
[0010] In some aspects of the invention, the measuring station
further is configured to accept payment information from the
individual, and in some aspects, the measuring station further is
configured to accept delivery information from the individual.
[0011] In some aspects of the invention, the measuring station
further is in communication with a lens fabricator and is
configured to transfer the correction data to a lens fabricator to
manufacture custom lenses, and in some aspects, the lens fabricator
is automated. Further, in certain aspects, the measuring station is
in communication with the automated lens fabricator and is
configured to transfer the correction data and delivery information
from the individual to a lens fabricator to manufacture custom
lenses, and in some aspects, the measuring station further is
configured to offer to and receive from the individual selected
sunglass frame styles.
[0012] In some aspects of this method of the invention, the
automated lens fabricator is further configured to assemble the
manufactured custom lenses with the selected sunglass frames, and
in some aspects of this embodiment, the measuring station further
is configured to accept payment information and delivery
information from the individual.
[0013] In yet other aspects, the lens fabricator is not automated.
In other aspects, based on the correction data for each eye,
off-the-shelf lenses are selected for the individual. In other
aspects, the lenses are manufactured by molding or by
machining.
[0014] In yet other aspects of this embodiment, the measuring
station comprises a wavefront phoroptor for measuring refractive
corrections of a focus error and a cylinder error for an eye, where
the wavefront phoroptor comprises: a wavefront sensing module for
providing the objective measurement of aberrations of the eye,
measuring wavefront slopes across a pupil, and determining wave
aberration of the eye that includes at least a cylindrical axis and
a cylindrical power in a resolution finer than 0.25 D; and a
phoroptor module with a plurality of spherical lenses and
cylindrical lenses and an acuity chart for subjectively determining
the focus error of the eye. In some aspects, the cylindrical lenses
are set according to the objective measurement of aberrations from
the wavefront sensing module; where the subjectively determined
focus error involves subjective responses by the individual to a
plurality of focus powers by the eye viewing an acuity chart, and
in some aspects, the wavefront sensing module measures aberrations
of the eye using a lenslet array wavefront sensor. In yet other
aspects, the objective measurement further includes a focus error,
a spherical aberration, a coma and other high-order aberrations,
and wherein the cylinder power and the cylinder angle is determined
for optimized vision from the determined wave aberration across a
pupil of the eye.
[0015] Yet other embodiments of the present invention provide a
measuring station configured for automatic data acquisition without
necessary intervention from a human other than the individual
configured to: obtain an objective measurement of wave aberration
from each eye of the individual; determine a measured cylindrical
power and a cylindrical axis from the objective measurement of wave
aberration; place a plurality of lenses according to the determined
measured cylindrical power and a cylindrical axis into a correction
module for the individual to see through and read an acuity chart;
determine a focus power of each eye through subjective refraction,
where the subjective refraction involves subjective responses from
the individual to a plurality of focus power corrections; and
communicate the measured cylindrical power, cylindrical axis and
focus power of each eye to a lens fabricator to manufacture custom
lenses or to a repository of off-the-shelf lenses.
[0016] Aspects of this embodiment of the invention include the
measuring station configured further to accept results from the
individual in reading the acuity chart through the correction
module and/or the measuring station further configured to allow the
individual to manually adjust the focus power of the correction
module. In other aspects, the measuring station further is
configured to transmit data for review by a human other than the
individual, wherein the transmitted data includes at least one of
a) records for the obtained objective measurement of wave
aberration from each eye of the individual, and b) results of the
individual in reading the acuity chart through the correction
device for a plurality of focus powers, and in some aspects, the
measuring station further is configured to take a picture of the
individual.
[0017] Other embodiments of the invention provide a system for
providing a pair of sunglasses to an individual, including
individuals with a visual acuity of 20/20 or better, comprising: a
measuring station configured for automatic data acquisition without
necessary intervention from a human other than the individual
obtain an objective measurement of wave aberration from each eye of
the individual and determine a measured cylindrical power and a
cylindrical axis from the objective measurement of wave aberration;
place a plurality of lenses according to the determined cylindrical
power and cylindrical axis into a correction module for the
individual to see through and read an acuity chart; and determine a
focus power of each eye through subjective refraction, wherein the
subjective refraction involves subjective responses from the
individual from a plurality of focus powers; and a lens fabricator
to manufacture custom lenses or a lens repository to provide
off-the-shelf lenses according to the measured cylindrical power,
cylindrical axis and focus power. In some aspects, the system
further comprises a database configured to receive payment and
delivery information from the individual.
[0018] Other embodiments of the invention provide a method for
providing a pair of sunglasses to an individual, including
individuals with a visual acuity of 20/20 or better, comprising the
steps of: 1) providing a measuring station to the individual, the
measuring station configured to automatically and without input
from a human other than the individual; obtain an objective
measurement of wave aberration from each eye of the individual;
determine a measured cylindrical power and a cylindrical axis from
the objective measurement of wave aberration; place a plurality of
lenses according to the determined cylindrical power and a
cylindrical axis from the objective measurement of wave aberration
into a correction device for the individual to see through and read
an acuity chart; and determine a focus power of each eye through
subjective refraction, wherein the subjective refraction involves
subjective responses from the individual to a plurality of
refractive corrections; 2) generating correction data from which to
manufacture lenses; 3) manufacturing the lenses or selecting a set
of off-the-shelf lenses appropriate for the correction data; 4)
fitting the lenses into frames to produce finished sunglasses; and
5) providing the finished sunglasses to the individual.
[0019] Yet other embodiments of the present invention provide a
kiosk system for prescriptive sunglasses or eyeglasses, configured
for automatic data acquisition without necessary intervention from
a human other than the individual, comprising: a wavefront sensing
module for providing objective measurement of aberrations of the
eye, wherein the wavefront sensing module measures wavefront slopes
across a pupil and determines wave aberration of the eye that
includes at least a cylindrical axis, and a cylindrical power in a
resolution finer than 0.25 D; a vision correction module for
presenting a plurality of refractive corrections for the individual
to see through, wherein the plurality of refractive corrections
includes: a cylindrical power and a cylindrical axis according to
the determined wave aberrations, and a plurality of focus power
corrections that is controlled manually by the individual; an
acuity chart for determining visual acuity of the eye under the
plurality of focus power corrections, human-to-machine interface
module to accept results from the individual in reading the acuity
chart through the correction module for a plurality of focus power
corrections; an exporting module for communicating data to a lens
fabricator to manufacture custom lenses or to a repository of
off-the-shelf lenses, wherein the communicated data includes at one
of the following: the measured cylindrical power, cylindrical axis
and focus power of each eye; records of the wavefront module for
data review; and results of the individual in reading the acuity
chart through the correction device for a plurality of focus power
corrections.
[0020] In another embodiment of the invention, a method of
manufacture for producing an ophthalmic lens is provided, including
automated methods of manufacture. In a first step, correction data
including wavefront aberration and focus power lens is transmitted
by a measuring station to a lens fabricator and is received by the
lens fabricator. In a second step, a semi-finished blank is
selected by the lens fabricator. In a third step, the semi-finished
blank is placed in a lens surfacing system in the lens fabricator.
In a fourth step, the surface of the semi-finished blank is
surfaced based on the correction data received from the measuring
station and a set of known refractive properties of the
semi-finished blank to create a fabricated lens. In a fifth step,
the refractive power of the fabricated lens is measured with a
lensometer to determine the refractive error between the refractive
power and the correction data. In a final optional step, the
surface of the fabricated lens is reworked based on the determined
refractive error until a measured cylindrical power of the
fabricated lens and the cylindrical power of the correction data
are within a tolerance of between 0.01 D and 0.08 D.
[0021] Various objects, features, aspects and advantages of the
present invention will become more apparent from the following
detailed description of preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1a shows a flow chart for a method for automated
measured correction of the eye and provision of sun- or eye-glasses
in accordance with one embodiment.
[0023] FIG. 1b shows a flow chart for a method for determining a
refractive correction of an eye that is in accordance with an
embodiment.
[0024] FIG. 2 shows aberrations in emmetropic eyes having
subjective visual acuity better than 20/20 without any refractive
correction.
[0025] FIG. 3 shows fractions of different aberrations in the total
aberration for emmetropic eyes having visual accuity better than
20/20 without any refractive correction.
[0026] FIG. 4 shows a flow chart for a method for determining
refractive correction of an eye in accordance with an
embodiment.
[0027] FIG. 5 shows an ophthalmic lens in accordance with an
embodiment.
[0028] FIG. 6 shows a method for previewing a refractive correction
of an eye in accordance with an embodiment.
[0029] FIG. 7 shows a phoroptor for subjective refraction of an eye
in accordance with an embodiment.
[0030] FIG. 8 shows another phoroptor for subjective refraction of
an eye in accordance with an embodiment.
[0031] FIG. 9 shows a flow chart for an improved method for a
manifest refraction in accordance with an embodiment.
[0032] FIG. 10a shows a schematic diagram of an exemplary
refraction system for determining a spherical power of an eye
subjectively for prescription of eyeglasses.
[0033] FIG. 10b shows a schematic diagram of a phoroptor as known
in the art, for subjective determination of a focus power, a
cylinder power, and a cylinder angle.
[0034] FIG. 11a shows a schematic diagram of a wavefront system of
an eye for prescription of eyeglasses in one embodiment.
[0035] FIG. 11b shows a schematic diagram of a conventional
wavefront system of an eye, which is also called aberrometer.
[0036] FIG. 12 shows an exemplary schematic diagram of a refraction
system for remote measurement of refractive errors in human
eyes.
[0037] FIG. 13 shows a schematic diagram of an integrated
refraction system for remote measurement of refractive errors in
human eyes, in one embodiment.
[0038] FIG. 14 shows a system for an electronic commerce method of
measuring refractive errors of an eye and delivering customized
eyeglasses, in one embodiment.
[0039] FIG. 15 shows a flowchart of an exemplary electronic
commerce method for the system of FIG. 14.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0040] Reference now will be made in detail to embodiments of the
present disclosure, one or more examples of which are illustrated
in the accompanying drawings. Each example is provided by way of
explanation of the present technology, not as a limitation of the
present technology. In fact, it will be apparent to those skilled
in the art that modifications and variations can be made in the
present technology without departing from the scope thereof. For
instance, features illustrated or described as part of one
embodiment may be used with another embodiment to yield a still
further embodiment. Thus, it is intended that the present subject
matter covers such modifications and variations as come within the
scope of the appended claims and their equivalents.
[0041] The present disclosure is drawn to refraction systems for
remote measurement of refractive errors in the eye in a location
such as a shop or office, by an examiner situated away from the
location. The remote measurement occurs through a network
connection such as internet, for example to enable electronic
commerce (e-commerce). Methods are disclosed for delivering
eyeglasses through remote measurement of refractive errors in human
eyes, and methods for franchise stores for eyeglasses.
Automated Measurement of the Eyes
[0042] The present disclosure is drawn to automated methods,
devices and systems to provide sunglasses and eyeglasses that allow
for vision correction, even for individuals with visual acuity of
20/20 or better. The present disclosure particularly is
revolutionary because it provides sunglasses for vision correction
of emmetropic eyes, when very typically sunglasses are sold
"off-the-shelf" with lenses that offer no optical correction.
Though sunglasses most typically do not offer refractive
correction, sunglasses are important as they offer protection from
UV rays, and protection from eye discomfort due to bright light.
Current sunglasses also typically offer options such as
polarization for glare reduction, and various lens colors such as
brown for enhanced depth perception and grey for color
fidelity.
[0043] The present disclosure is applicable for frames of any
shape, and particularly applicable to sunglasses (or goggles) that
have wrap shapes, since for such configurations, correction of
vision is important because the lens is not parallel to the cornea.
Thus, in contrast to the conventional approach to selling
sunglasses, the present disclosure is drawn to automated methods,
devices and systems that provide sunglasses that allow for enhanced
vision correction, even in individuals that have a visual acuity of
20/20 or better or in individuals who wear contact lenses for
vision correction.
[0044] Emmetropia is defined as the state of vision where an object
at infinity is in sharp focus with the eye lens in a neutral or
relaxed state. This condition of the normal eye is achieved when
the refractive power of the cornea as well as the crystalline lens
and the axial length of the eye balance out, which focuses rays
exactly on the retina of the eye, resulting in perfect vision. An
eye in a state of emmetropia requires no correction; however,
emmetropic eyes actually are not perfect. For example, FIGS. 2 and
3 demonstrate that there are optical defects for emmetropic eyes
between 20/20 and 20/10. Further, sunglasses provide additional
challenges for emmetropes. For example, the reduced light level due
to the darkened lenses can cause problems, as can the transition
from bright light to clouded or overcast conditions.
[0045] Moreover, the inventor has collected additional clinical
data indicating that astigmatism (cylinder error) in eyes with an
acuity of 20/10 or 20/12 can be as large as 0.60 D in some eyes as
measured by a wavefront aberrometer; and that correcting an eye's
astigmatism in 20/10 and 20/12 eyes showed significant medical
benefits for sunglasses. It was found that both brightness and
contrast improved as did depth perception. The inventor also has
collected more clinical data in individuals with an acuity of
20/25, 20/20, or 20/16 showing that both focus error and cylinder
error (astigmatism) are important. Astigmatism in eyes with a
visual acuity of 20/25, 20/20, or 20/16 can be as large as 1.0 D in
some eyes, as measured by a wavefront aberrometer; and that
correcting an eye's focus error and astigmatism in eyes with a
visual acuity of 20/25, 20/20, or 20/16 can improve visual acuity
by 2 to 4 lines, and brightness, contrast and depth perception are
improved.
[0046] FIG. 1a shows a flow chart for a method for automated
measured correction of the eye and provision of sun- or eye-glasses
to an individual in accordance with one embodiment. First, a
measuring station or kiosk 110 is provided. The measuring station
or kiosk preferably comprises: 1) a comfortable place for the
individual to sit; 2) a wavefront sensing module for providing
objective measurement of aberrations of the eye; where the
wavefront sensing module measures wavefront slopes across a pupil
and determines wave aberration of the eye that includes at least a
cylindrical axis, and a cylindrical power in a resolution finer
than 0.25 D; 3) a vision correction module for presenting a
plurality of refractive corrections for the individual to see
through, where the plurality of refractive corrections includes a
cylindrical power and a cylindrical axis according to the
determined wave aberrations, and a plurality of focus powers that
are controlled manually by the individual; 4) an acuity chart for
determining visual acuity of the eye under the plurality of focus
power corrections; 5) a human-to-machine input module for the
individual to communicate with the measuring station, to accept
results from the individual in reading the acuity chart through the
correction module for a plurality of focus power corrections, and,
optionally, to accept delivery information from the individual; 6)
an exporting module for communicating data to a lens fabricator to
manufacture custom lenses or to a repository of off-the-shelf
lenses, where the communicated data includes at least one of the
following: the measured cylindrical power, cylindrical axis and
focus power of each eye; records of the wavefront module for data
review; or results from the individual reading the acuity chart
through the correction device for a plurality of focus power
corrections; 7) optionally, an image module for taking a picture of
the individual with and/or without the selected sunglass frames;
and 8) optionally, an electronic payment module for accepting
payment information from the individual.
[0047] The measuring station 110 is configured to: 1) automatically
acquire data without intervention from a human other than the
individual, by obtaining an objective measurement of wave
aberration from each eye of the individual 111; 2) determine a
measured cylindrical power and a cylindrical axis from the
objective measurement of wave aberration 112; 3) place a plurality
of lenses according to the determined cylindrical power and a
cylindrical axis into a correction module for the individual to see
through and read an acuity chart 113; 4) allow the individual to
manually adjust the focus power of the correction device and read a
resolution target for a plurality of focus powers 114; 5) accept
results from the individual in reading the acuity chart through the
correction module 115; and 6) optionally, transmit data via an
electronic media for review by a human other than the individual
116, where the transmitted data includes at least one of a) records
for the obtained objective measurement of wave aberration from each
eye of the individual, and b) results of the individual in reading
the acuity chart through the correction device for a plurality of
focus powers.
[0048] Additionally, the measuring station 110 is configured to
determine a focus power of each eye through subjective refraction,
where the subjective refraction involves the measuring station
receiving subjective responses from the individual to a plurality
of focus powers 120.
[0049] The measuring station of the present disclosure determines
focus power under a cylindrical correction according to wavefront
measurements. Cylinder power and cylinder axis both have an impact
on subjective focus power. The advantages of determining cylinder
power and cylinder axis according to wavefront measurements include
eliminating the two independent knobs typically used in the art to
measure subjective refraction. This provides state-of-the-art
quality of vision after correction as the eye is astigmatism-free
according to objective measurement of the eye's wave aberration.
Focus power must be determined subjectively because the eye can
accommodate for different focuses, ensuring perfect focus power
avoiding overcorrection and undercorrection.
[0050] The automated measuring station of the present disclosure
provides many advantages described above, and provides additional
advantages. Traditional refractive correction requires subjective
refraction for at least three parameters: focus power, cylinder
power and cylinder angle, and these parameters are most often
measured by a professional such as an optometrist or an optician.
The measurements taken are often complicated because traditional
instruments have three independent knobs for vision
optimization--thus, such measurements and instrumentation cannot be
automated. However, the methods and devices of the present can be
automated because cylinder angle and cylinder axis are precisely
determined objectively via a wavefront aberrometer. It is
well-known that conventional auto-refractions cannot distinguish
image blurs caused by focus error, cylinder error (cylinder power
& cylinder axis), spherical aberration, coma and a host of
other high-order aberrations in the eye. When human vision is
optimized in a conventional auto-refractor for the sharpest image
possible, determination of the eye's cylinder power and cylinder
angle is impacted by the real-time focus error (the eye's
accommodation) as well as the eye's other aberrations: spherical
aberration and coma. Unlike conventional auto-refractors, a
wavefront aberrometer measures all aberrations in an eye
independently through a wavefront sensor. Measurement of the eye's
cylinder power and cylinder axis is thus not influenced by the
eye's real-time focus error such as accommodation or by spherical
aberration, coma, and many other high-order aberrations. A
wavefront aberrometer provides cylinder angle and cylinder power
with unprecedented precision, so that they can be used as the final
cylinder power and cylinder axis without the need of subjective
validation as in the conventional manifest refraction.
Additionally, focus power of any eye must be subjectively
determined as the eye must accommodate for different distances,
refraction of the eye requires only one knob, which can be
manipulated by the individual patient at the measuring station.
[0051] The wavefront sensor that is part of the measuring station
of the present disclosure can be run automatically on command, and
unlike a conventional auto-refractor, it can provide wavefront
sensor images for independent review so that wavefront measurement
can be validated later by an individual such as a optical
professional, if desired. When an automatic measurement of eye's
cylinder power and cylinder angle is used for fabricating a
correction lens, it is preferred in some embodiments to have an
independent validation by a human other than the tested individual.
Wavefront images and their analysis provide direct evidence for
another individual to determine whether the automatic measurement
of the cylinder angle and the cylinder power are acceptable.
Conventional autorefractors do not have the necessary information
for an independent validation. Additionally, for the validation and
determination of focus power of the eye, it is preferred that
another individual review subjective acuity for a plurality of
focus powers. Otherwise, because the eye can accommodate to
different focus powers, focus power determined by the tested
individual based on best visual acuity alone can lead to
overcorrection leading to hyperopia of the eye. In some
embodiments, the methods further comprise allowing a human other
than the tested individual to review data transmitted from the
measuring station and to allow the individual to send feedback data
remotely to the measuring station to correct any errors in or fine
tune the automatic measurements.
[0052] The measuring station of the present disclosure may also
provide additional functionalities. For example, the measuring
station may present to the individual a selection (different styles
and/or sizes and/or colors) of sun- or eyeglass frames for
consideration, either physical samples or virtual samples. In
addition, the measuring station may take a digital photograph of
the individual so that the individuals can "virtually" try on
different frame styles, sizes and colors, with the digital images
provided to the individual by the measuring station. Moreover, the
digital images provided may serve a purpose aside from aesthetics
and fashion; for example, another advantage of taking a photograph
is as glasses frames are positioned on an individual's face, the
lenses will be positioned in relation to the eye--more or less
uniquely depending on the individual's face and the frames
selected. Taking a photograph of the individual's face in
combination with information about the frame style and size
selected allows software associated with the measuring station to
optimize alignment of the optical center of the lens with the
individual's eye's pupils. Other functionalities that may be
associated with the measuring station include the measuring station
accepting payment from the individual, accepting prescription
information for an individual (to provide vision correction in
accordance with a prescription with, e.g., additional vision
correction as determined by the methods of the present disclosure),
accepting delivery (e.g., shipping) information from an individual,
and accepting a focus power for near vision of an individual with
presbyopia so that the sunglasses can be made as bi-focal,
tri-focal, and progressive lenses.
[0053] In another step of FIG. 1a, correction data based on the
measured wave aberrations and focus power (correction data) is
generated by the measurement station 110, or by a computer in
communication with the measurement station. In another step, the
correction data 130 (along with other data such as digital image,
prescription, payment, delivery and/or any other pertinent data) is
then transmitted from the measurement station (or computer in
communication with the measurement station) via electronic media to
a lens fabricator.
[0054] The lens fabricator may be a manual lens fabricator or may
be an automated lens fabricator. Descriptions of lens fabrication
are provided herein in the section entitled "High-precision toric
lenses for refractive corrections" and in conjunction with the
description of FIG. 5. Essentially, lenses are manufactured by
molding or machining or a combination of the two 140. For example,
semi-finished lens blanks are "generic" lenses that provide a
certain range of correction, and then are typically custom finished
to precise specifications based on the correction data (or
prescription) for the individual. The present disclosure
contemplates transmitting data to an automated, a semi-automated or
a manual lens fabricator, where lenses are manufactured based at
least on the correction data transmitted by the measurement station
to the lens fabricator. In addition to fabricating the lenses, the
lens fabricator may also fit the lenses into the frames of the sun-
or eyeglasses 150. Finally, the finished sun- or eyeglasses are
provided to the individual 150. As with the manufacturing step and
the fitting step, providing the finished sun- or eyeglasses to the
individual may be an automated process, a semi-automated process,
or a manual process based on, e.g., delivery information provided
by the individual, input into the measurement station or otherwise
provided by the individual.
Improved Methods for Determining a Refractive Correction of an
Eye
[0055] FIG. 1b shows a flow chart for an improved method for
determining a refractive correction of an eye based on an objective
measurement of the eye's wave aberration and a subjective
measurement of the eye's focus error in accordance with steps 111,
112 and 120 of FIG. 1a. This improved method enables the production
of an optimized astigmatism-free refractive correction so that a
majority of normal human eyes can achieve visual acuity of 20/10
instead of conventional 20/20 and provides even individuals with a
visual acuity of 20/10 with corrected, enhanced vision.
[0056] First, in step 10, an objective measurement of all the
aberrations in an eye is obtained, wherein all aberrations are
expressed in a wave aberration W(x,y). Second, in step 11, an
objective sphero-cylindrical correction is determined from the
obtained wave aberration by optimizing vision of the eye through
removal of measured focus errors and cylindrical errors. The
objective sphero-cylindrical correction comprises a focus error, a
cylindrical power, and a cylindrical axis. Third, in step 12, a
focus error of the eye is obtained through a subjective refraction,
wherein the subjective refraction involves measuring vision
performance of an eye based on subjective responses to a plurality
of refractive corrections. Finally, in step 13, refractive
correction data for an ophthalmic lens or refractive procedure is
generated by combining the objectively determined cylindrical
power, the objectively determined cylindrical axis, and the
subjectively determined focus error.
[0057] The method described has many advantages in comparison to
conventional vision correction. First, cylindrical error in an eye
as little as 0.025 D can be precisely determined just like other
high-order aberrations such as spherical aberration and coma in an
eye, because the refraction process does not depend on the limited
cylindrical lenses in a phoroptor, subjective feedback about the
fine difference between different cylindrical corrections by the
tested subjects, and subjective optimization strategies used by the
practitioners. Second, the cylindrical axis can be precisely
determined and a tolerance for an error in cylindrical axis can be
determined from the calculated image quality of an eye. Finally,
vision optimization is no longer limited to a specific situation in
a manifest refraction. Instead, virtual optimization can be applied
to take account of different conditions of vision at different
pupil sizes through the use of vision simulation of outdoor vision,
indoor vision, and night vision.
[0058] In contrast to the objective wavefront refraction using a
wavefront aberrometer as described in U.S. Pat. No. 5,777,719 by
Williams and Liang, the method described also addresses the issue
of measuring focus error in the eye using an objective refraction.
Objective wavefront sensors like a wavefront aberrometer can
measure focus error accurately, but cannot guarantee that the
measured focus error is the best for far vision of an eye for two
reasons. First, human eyes are known to change focus power by the
crystalline lens at different viewing distances, which is also
called accommodation. An objective wavefront sensor can only
measure the focus error of an eye at one particular accommodation
state. Second, objective wavefront sensors like an objective
aberrometer only measure focus error of an eye at one particular
wavelength of light, which is often in the infrared spectrum to
assure the patient remains comfortable during the objective
refraction. Chromatic aberration for perception must be taken into
account for determining the best focus for an eye for the far
accommodation point. Therefore, the focus error obtained from an
objective refractor could be the true focus error for the far
accommodation point within +0.125 D for only about 20% of measured
eyes.
[0059] About 40% of eyes will be under-corrected based on the focus
error derived from an objective refractor, which will lead to a
visual acuity below 20/20. At the same time, another 40% will be
over-corrected based on the focus error obtained from an objective
refractor, which leads to hyperopic vision after the refractive
correction. The improved method for determining a refractive
correction discussed here in accordance with the present disclosure
uses a subjective approach to revise the focus error from the
objective refractor, and thus takes into account both accommodation
and chromatic aberration for an optimized refraction of the eye's
far accommodation point.
[0060] The described improved method for determining a refractive
correction can further include a preview of vision correction, as
in step 14, even before an ophthalmic lens is made.
[0061] Prediction of vision may include convolved retinal images of
acuity charts, calculated modulation transfer functions, calculated
point-spread functions, and simulation of nighttime symptoms. The
calculated vision performance can be shown to a patient as well as
a practitioner for accepting or selecting a specific refractive
correction.
[0062] The described improved method for determining a refractive
correction enables an optimized astigmatism-free refraction for
every eye. Perfect correction of an eye's cylindrical error can
have significant impact on the visual acuity of a corrected eye.
FIG. 2 shows the cylindrical error as well as the total aberration
in more than 200 eyes with visual acuity better than 20/20. All the
tested eyes are naturally emmetropic without any refractive
correction. The cylindrical error and total aberrations in each eye
are measured with an objective wavefront sensor and calculated
based on the pupil size for each eye during the subjective
measurement of visual acuity. The pupil size of acuity measurements
ranges between 2.5 mm and 4.5 mm with an average pupil size of 3.7
mm. The error bars in FIG. 2 is one standard deviation for the
measured population.
[0063] As can be seen in FIG. 2, the objectively measured
cylindrical error and the subjectively measured acuity are
correlated. In addition, it is clear that the cylindrical error is
the dominant factor in determining subjective visual acuity.
[0064] FIG. 3 also highlights the importance of cylindrical error
for visual acuity in naturally emmetropic eyes. FIG. 3 shows
averaged fractions of different aberrations in the total
aberrations for emmetropic eyes in four acuity groups in a yet to
be published clinical study. It is seen that the cylindrical error
accounts for 60% to 80% of all aberrations in emmetropic eyes in an
acuity test. Coma has a much smaller contribution of 10% to 20%,
while spherical aberration has negligible impact on visual
acuity.
[0065] From the data in FIG. 2 and FIG. 3, it is not difficult to
conclude that quality in correcting the cylindrical error in an eye
has significant impact on subjective visual acuity. Visual acuity
of 20/10 or 20/12 can usually be achieved just by a perfect
correction of cylindrical error. Although important for vision at
nighttime, additional correction of coma, spherical aberration, and
other high-order aberrations has negligible impact on visual acuity
for the majority of normal human eyes.
[0066] Perfect correction of an eye's cylindrical error requires
precise measurements and specification of the cylindrical error in
an eye. It is therefore necessary to specify cylindrical power much
finer than the conventional resolution of 0.25 D, e.g. 0.025 D.
[0067] It is also important to record cylindrical axis in the
objective measurement. One embodiment for recording the cylindrical
axis is to record a digital picture of an eye while the objective
measurement of cylindrical error is taken. The digital picture can
later be used to assist the placement of an ophthalmic lens in an
eye, or to verify proper orientation of an ophthalmic lens.
[0068] The described method for determining a refractive
correction, when combined with innovations also described in the
present application for advanced lens making, will enable an
astigmatism free customized refractive correction that is superior
in visual performance to the conventional method for vision
correction based on conventional manifest refraction.
[0069] In one embodiment of the present disclosure, a method for
obtaining an astigmatism-free customized refractive correction
comprises the steps as follows. First, a wave aberration of an eye
is obtaining objectively, wherein the wave aberration includes
focus error, astigmatism, coma, and spherical aberration in the
eye. Obtaining a wave aberration of an eye objectively can be
achieved by measuring wave aberration of an eye using a device like
an objective aberrometer as described in U.S. Pat. No. 5,777,719 by
Williams and Liang. Second, a cylindrical power and a cylindrical
axis are determined from the objectively obtained wave aberration.
The resolution for the cylindrical power must be finer than 0.25 D,
e.g., 0.025 D. The specification for the determined cylindrical
power has a resolution between 0.01 D to 0.1 D. Cylindrical axis
must also be precisely determined. Third, a focus power of the eye
is determined through subjective refraction. Subjective refraction
can be achieved through the use of a phoroptor presented by the
measuring station or kiosk to the individual patient. Fourth, a
refractive prescription for an ophthalmic lens or for a refractive
procedure is generated by combining the objectively determined
cylindrical power and cylindrical axis, and the subjectively
determined focus power. Fifth, a pre-made lens most closely
correlating to the determined cylindrical power, cylindrical axis
and focus power is selected from a stock of such lenses or a
customized ophthalmic lens is fabricated based on the generated
high-precision refractive correction data with a high-precision
cylindrical power. In preferred embodiments, the cylindrical power
has a resolution finer than 0.25 D, e.g., 0.025 D, with a tolerance
between 0.01 D and 0.05 D. Additionally, the refractive correction
can further include a spherical aberration that is determined from
the wave aberration. Reducing spherical aberration in some eyes can
improve night vision, particularly for those eyes with known
nighttime symptoms such as glare and halo.
[0070] In another embodiment of FIG. 1b, a simplified method for a
perfect correction of eye's cylindrical error is shown in FIG. 4.
This embodiment does not involve measuring high-order aberrations
such as spherical aberration and coma. First, in step 41, a
cylindrical error of an eye is determined using an objective
procedure without any subjective responses. For improved accuracy
in determining the cylindrical error, the objective procedure in
step 41 might involve measuring refractive properties of an eye in
a pupil size between 2.5 mm and 4 mm pupil, and taking an average
measurement for a plurality of independent objective measurements.
Second, in step 42, a focus error of the eye is determined through
a subjective refraction measuring vision performance of an eye
based on subjective responses to a plurality of refractive
corrections. Third, in step 43, correction data used to select or
manufacture an ophthalmic lens is generated by combining the
determined cylindrical refractive error and the determined focus
error, wherein the cylindrical error has a finer resolution less
than the traditional 0.25 D, e.g., 0.025 D.
High-Precision Toric Lenses for Refractive Corrections
[0071] Due to the limitations in the conventional manifest
refraction, ophthalmic lenses today are made with a cylindrical
power resolution of 0.25 D. Corrections of astigmatism in human
eyes using real spectacle lenses is further complicated because
lenses are in reality made with a relative large tolerance of
between +0.09 D for low power lenses and up to +0.37 D for high
power lenses. Therefore, spectacle lenses for astigmatism-free
customized refractive corrections must be made using more advanced
technologies.
[0072] FIG. 1a provides a step to manufacture lenses based on the
correction data generated and transmitted by the measuring station.
Spectacle lenses today are made using either: lens molding or lens
machining using computer-controlled lathes. For the majority of
spectacle lenses in a normal refraction range (spherical power
between -6 D and +6 D), lenses are typically molded in batches, and
stocked either in labs or in lens shops. Two lens molds are needed,
and one mold has a base curve that is either spherical or aspheric
in shape and the other mold has a toric shape if the spectacle lens
has a cylindrical power. For lenses with a refractive power beyond
the normal range, lenses are usually fabricated from semi-finished
lens blanks that are molded in batches and stocked in factories. A
semi-finished lens blank contains a finished base surface in a
spherical or aspheric curve and a top prescription or machinable
surface that will be surfaced based on the lens prescription and
optical power of the base surface. If the fabricated lens has a
cylindrical power, the top surface will have a toric shape.
[0073] For both molded lenses and machined lenses with a
cylindrical power, the finished lenses consists of a base curve
that is spherical or aspheric in shape, and a prescription or
machinable curve that is toric in shape for a custom lens with a
cylindrical power. The base curve is often set to one of 5 to 8
possible surface shapes, while the prescription or machinable
surface must be capable of taking on the shape of one of several
hundred curves in order for the combined lens to correct for
different combination of spherical and cylindrical powers with the
conventional resolution of 0.25 D.
[0074] For spectacle lenses with a fine cylinder resolution of
0.025 D instead of 0.25 D, manufactures would need ten times more
prescription curves if they continued to use the conventional lens
shape with one toric surface. Although possible in theory, making
custom lens for astigmatism-free correction using one toric surface
would be prohibitively expensive because of the enormous number of
molds that would be needed.
[0075] FIG. 5 illustrates new spectacle lenses in accordance with
the present disclosure for astigmatism-free customized refractive
correction. In one embodiment of the present disclosure, the lens
comprises a toric surface 51 that is a modified version of
traditional base curves used in conventional lenses. A small amount
of cylindrical power (<0.25 D) can be added to a traditional
base curve for fine tuning cylindrical power at a resolution below
0.25 D. The other toric surface 52 can be the same as those used in
making conventional toric lenses, which have cylindrical powers
ranging from 0.00 D to 6.00 D with a resolution of 0.25 D. Both the
base curve and the prescription or machinable curve can also have
aspheric characteristics for reducing oblique astigmatism just like
conventional toric lenses.
[0076] Two embodiments can be used for fine tuning cylindrical
powers as fine as 0.025 D. One of the embodiments involves a fixed
cylindrical power of 0.25 D or 0.125 D at the base curve, adjusting
the angle between the two cylinder axes, and thereby achieving
cylindrical power resolution as fine as 0.025 D. The other
embodiment involves a plurality of cylindrical powers for each base
curve (0.025 D, 0.05 D, 0.075 D, 0.10 D, 0.125 D, and 0.2 D),
combining the cylindrical power from the base curve and the
prescription curve, and thereby achieving fine cylindrical power as
fine as 0.025 D. In the second embodiment, axes of the two toric
surfaces can be made to coincide to achieve the designed
cylindrical powers, or slightly different for further tuning of
cylindrical powers.
[0077] For manufacturing lenses with two toric surfaces that both
have cylindrical powers, it is important to control orientations of
the two cylinder axes to achieve a desired cylindrical power. When
a spectacle lens is molded with two toric molds, each mold can have
a machine-readable mark. Two molds should be aligned on their
cylinder axes before being put together to form a cavity for
molding a lens. When a lens is machined for two toric surfaces, the
semi-finished blanks can contain a machine readable mark to
indicate the cylindrical axis of the finished surface. The
cylindrical axis of the machined surface should be precisely
controlled in reference to the axis of the pre-finished
surface.
[0078] In another embodiment, the ophthalmic lens in FIG. 5 can be
further configured to induce spherical aberration at the central
vision for the correction of spherical aberration in an eye. This
can be achieved by shaping one of the two toric surfaces with an
aspheric component around optical axis.
[0079] The ophthalmic lens of in FIG. 5 can further be configured
to have aspheric shapes away from the optical axis for reduced
off-axis Seidel aberrations. It can also be configured for a
bi-focal lens or a progressive lens.
Controlling Cylindrical Power by Arranging Cylinder Axes of Toric
Surfaces
[0080] Cylindrical powers in a fine resolution can be achieved by
arranging the cylinder axes of two toric surfaces with coarse
powers. In accordance with the present disclosure, the method
requires two toric surfaces, where one of the two surfaces has a
dominant cylindrical power in one direction .PHI..sub.A1 while the
other surface has a small biasing cylindrical power at a different
orientation .PHI..sub.A2. The angle between the two cylinder axes
is measured by .quadrature..
[0081] The combined cylindrical power can be expressed by an
analytical expression:
.quadrature..sub.A=SQRT(.quadrature..sub.A1*.quadrature..quadrature..sub-
.A1+.quadrature..quadrature..sub.A2.quadrature..quadrature..quadrature..qu-
adrature..sub.A2+2*.quadrature..quadrature..sub.A1.quadrature..quadrature.-
.sub.A2*COS(2.quadrature.)) (1)
where SQRT is the mathematic operator of square root. The combined
cylindrical power .PHI.A is between .PHI..sub.A1-.PHI..sub.A2) and
(.PHI..sub.A1+.PHI..sub.A2), depending on the angle between the two
cylinder axes. In one example, if the dominant cylindrical power
.PHI..sub.A1 has a cylindrical power of 1.0 D and the bias
cylindrical power is 0.125 D, any cylindrical power in a fine
resolution between 0.875 D and 1.125 D can obtained using these two
base cylindrical powers. In another example, a base bias
cylindrical power of 0.25 D and 12 base dominant cylindrical powers
of 0.25 D, 0.75 D, 1.25 D, 1.75 D, 2.25 D, 2.75 D, 3.25 D, 3.75 D,
4.25 D, 4.75 D, 5.25 D, 5.75 D, is used to achieve any cylindrical
power between 0.00 D and 6.00 D with a resolution finer than 0.25
D.
[0082] There are at least three advantages associated with making a
lens with a cylindrical power using two cylinder elements arranged
at different cylinder axes. First, a high-resolution, adjustable
cylindrical power can be achieved by arranging the relative
orientation of the two cylinder axes. Controlling two cylinder axes
within 2.5 degree is relatively easy in a manufacture process in
comparison to a precise control of surface shape within 0.02 D.
Second, making cylinder lenses in a fine resolution of cylindrical
power is dramatically simplified and is low-cost because only a
limited number of base molds are required. Third, a high-speed
process can be achieved by fabricating all lenses with one bias
power or just a few biasing cylindrical powers. High-definition
lenses can then be custom manufactured just like a conventional
lens with a limited number of cylindrical powers. One only needs to
pay attention to the relative angle between the two cylinder
axes.
[0083] It must be mentioned that arranging two cylindrical powers
at various orientations will cause a variable focus offset to the
base spherical power. The induced spherical power can be expressed
as
.quadrature..sub.S=0.5*(.quadrature..sub.A1+.quadrature..sub.A2-.quadrat-
ure..sub.A) (2)
where .PHI..sub.A1, .PHI..sub.A2 and .PHI.A are the dominate
cylindrical power, the biasing cylindrical power and the combined
cylindrical power, respectively. The total focus change depends on
the angles between the two cylindrical axes, and can be as large as
the biasing cylindrical power if the full range of angle between
the two cylinder axes is 90 degrees. Because of the focus offset,
this cylinder control method cannot be used for making conventional
lenses with a resolution of 0.25 D.
[0084] When the bias cylindrical power is less than 0.25 D, the
focus change in spectacle lenses can be addressed in two different
ways. First, for eyes with significant accommodation range, the
focus change in Eq (2) can be factored into the total spherical
power. Second, for eyes with no or little accommodation, more than
one bias power is needed to reduce the induced focus offset in Eq.
(2). In this case, one may need five to ten bias powers and use a
small angular range for fine tuning the combined cylindrical
power.
[0085] In addition to making lenses with precise control of
cylindrical power, the method of arranging two cylindrical powers
described has three other applications. First, precise control of
cylindrical power can be achieved even if the bias cylindrical
power and the dominant cylinder are known to have manufacturing
errors. A compensation angle can be calculated for eliminating the
errors in the bias and dominant cylindrical powers. Second, one can
use the principle described to build an improved phoroptor for
preview of astigmatism-free custom vision corrections. Third, this
method can also be used for making customized intra-ocular
lenses.
Closed-Loop Methods for Making Customized High-Precision Toric
Lenses
[0086] Customized spectacles for astigmatism-free refractive
correction cannot be manufactured in today's labs using existing
technologies because today's spectacle lenses are manufactured in a
coarse resolution of 0.25 D and a rough tolerance between +0.09 D
to +0.37 D as illustrated in British standard for tolerances on
optical properties of mounted spectacle lenses (BS 2738-1:1998).
Novel methods are required for making high-precision lenses for an
astigmatism-free customized refractive correction.
[0087] A method for fabricating a customized toric lens for the
high-definition refractive correction of a human eye in accordance
with the present disclosure would utilize a closed-loop process.
First, a manufacturer would receive custom correction data for the
manufacture of a toric lens with a spherical power, and a
cylindrical power in a finer resolution than 0.25 D, e.g., 0.025 D.
Second, desired surface profiles for a lens would be determined
based on the obtained refractive correction data and the material
used for making the ophthalmic lens.
[0088] Third, a customized toric lens would be fabricated either
through lens molding or by surfacing a semi-finished blank based on
the determined surface profiles. Fourth, each fabricated custom
lens would be measured with a lensometer. The lens would be
delivered to a customer only if the measured cylindrical power of
the manufactured lens and the cylindrical power of the manufactured
lens were within a custom tolerance level between 0.01 D and 0.08
D, e.g., 0.025 D. The lens would be reworked by surfacing at least
one of the two surfaces if the difference between the measured
cylindrical power of the manufactured lens and the cylindrical
power measured by the measuring station is not within a custom
tolerance level.
[0089] In another embodiment of the present disclosure, the closed
loop process for making a high-precision spectacle lens comprises
the steps of: a) obtaining correction data (in some embodiments, a
prescription) that comprises a spherical focus power, a cylindrical
power, and an optional cylindrical axis and spherical aberration;
b) determining desired surface profiles for a lens based on the
obtained refractive prescription and the material used for making
the ophthalmic lens; c) mounting a component in the form of an
optical piece or a partially processed optical element into a
manufacture system and altering at least one surface profile of the
component according to the determined surface profiles; d)
measuring refractive properties of the altered component using a
lensometer; f) calculating residual errors of the manufactured lens
from the obtained correction data and the measured refractive data
of the altered component; e) further changing at least one surface
profile of the component based on the calculated residual errors
until the residual errors of the manufactured lens are within a
custom tolerance between 0.01 D and 0.08 D, e.g., 0.025 D.
Methods for Previewing an Astigmatism-Free Refractive
Correction
[0090] Even though objective wavefront refractors provide precise
measurements of cylindrical power and cylindrical axis of an eye,
it is still preferred to preview the cylinder correction before a
lens is made for the cylindrical correction.
[0091] A phoroptor is a device normally used in an optometry office
for the subjective determination of a spherical focus power, a
cylindrical power, and a cylindrical axis of an eye. Differences in
cylindrical powers for a refractive correction are limited by a
resolution of 0.25 D while differences in cylindrical axis are set
by a resolution of about 5 degrees. Cylindrical axes in a phoroptor
are never precisely related to an objective refraction in optometry
practice. Therefore, conventional phoroptors in the prior art are
not suited for high-definition refractive correction.
[0092] FIG. 6 shows a method for previewing an astigmatism-free
refractive correction of an eye in accordance with the present
invention. In one embodiment, the method for previewing an
astigmatism-free refractive correction of an eye in accordance with
the present invention comprises the steps of: a) obtaining
correction data of a refractive correction of an eye from an
objective refractor 60, wherein the objective refractor measures
wavefront slopes across the pupil of an eye, and precisely
determines a cylindrical power (at a resolution finer than 0.25 D),
a cylindrical axis, an optional spherical aberration, and a rough
estimate of a spherical focus power of an eye; b) dialing-in the
determined cylindrical power and cylindrical axis in a phoroptor
61, wherein the cylinder parameters are controlled precisely with a
resolution finer than 0.25 D; c) setting the spherical focus power
to a plurality of values and measure visual acuity of an eye
subjectively through phoroptor 62; d) determining an optimized
focus power subjectively that sets the eye's accommodation at the
far point 63; e) determining the best corrected acuity under
preview and provide a refractive prescription 64 based on the
subjectively determined focus power and the objectively determined
cylindrical power and cylindrical axis.
Improved Phoroptors for Measuring Refractive Errors of an Eye
[0093] The method of previewing an astigmatism-free refractive
correction in accordance with the method described above may be
achieved using a phoroptor equipped with a wavefront aberrometer.
In one embodiment, such an advanced phoroptor would comprise the
following modules: a wavefront sensing module for providing an
instant and objective measurement of an eye's aberrations; an
output module for displaying the measured aberrations that include
at least a focus error, a cylindrical axis and a cylindrical power
in a resolution finer than 0.25 D, e.g., 0.025 D; a mechanical
mechanism for moving the wavefront aberrometer to a position for
measuring the eye's aberrations as well as for moving the wavefront
aberrometer away from the optical axis of the eye for other
measurements of the eye, a phoroptor module for performing
subjective refraction of an eye using a plurality of spherical
lenses and cylindrical lenses, wherein the phoroptor module may not
correct high-order aberrations such as spherical aberration and
coma; and a mechanism in the phoroptor module for dialing in a
cylindrical power and cylindrical axis obtained from the output
device of the wavefront aberrometer so that an astigmatism-free
vision correction is achieved. The wavefront module would also
measures all aberrations in the eye and provide image metrics
derived from the measured aberration in the eye.
[0094] By design, conventional phoroptors in the prior art are not
suited for astigmatism-free refractive corrections. An improved
phoroptor must address the issues of relating the cylindrical axis
of the phoroptor to the orientation of the eye in an objective
refractor, and controlling cylindrical power in a resolution much
finer than 0.25D.
[0095] FIG. 7 shows an improved phoroptor for inclusion in the
measuring station to allow for subjective refraction of an eye in
accordance. A registration mark 72 is placed on face of a patient.
An objective refraction of the eye can be obtained with its
cylindrical axis relating to the alignment mark 72. When the same
eye is placed behind a phoroptor, a light beam 71 from the
phoroptor can be placed next to the registration mark for relating
the cylindrical axis of the phoroptor to an orientation of the eye
in another measurement.
[0096] Relating the cylindrical axis of a phoroptor to an
orientation of an eye in an objective refractor may involve using
the aid of a mechanical device, a light beam, a projected image, or
an image device. Relating the cylindrical axis of a phoroptor to
the cylindrical axis of an eye in an objective refractor may also
involve comparing a fixed orientation such as an alignment mark 71
attached to a phoroptor to an orientation of an eye such as a
registration mark 72 on the face of a patient or in an eye.
Relating the cylindrical axis of a phoroptor to the cylindrical
axis of an eye in an objective refractor may involve adjusting an
orientation such as an alignment mark 71 attached to a phoroptor to
match to an orientation of an eye specified by a registration mark
72 on the face of a patient or in an eye, and determining an
angular offset from the adjustment to the alignment mark attached
to the phoroptor.
[0097] The improved phoroptor associated with the measuring station
further includes a digital control and display of its cylindrical
axis instead of a manual control of the cylindrical axis 73. The
digital control may be achieved using motorized control of the
cylindrical axis.
[0098] The improved phoroptor can further include a mechanism for
achieving cylinder correction continuously instead of every 0.25 D
as in conventional phoroptors.
[0099] The improved phoroptor can further include a mechanism for
achieving refractive correction of spherical aberrations in an eye
using a plurality of phase plates or a plurality of lenses with
aspheric surface profiles.
[0100] In another embodiment, an improved phoroptor for subjective
refraction of an eye includes a mechanism for entering a
cylindrical power and a cylindrical axis manually or for importing
refractive data from an objective refractor for improved efficiency
and accuracy. Such a phoroptor is illustrated in FIG. 8 and
comprises: a) a plurality of spherical lenses for the correction of
defocus in an eye; b) a plurality of cylindrical lenses for the
correction of astigmatism in an eye; c) a mechanism 81 for
importing refractive data from an objective refractor.
Improved Objective Refractors for Refractive Correction of an
Eye
[0101] A conventional wavefront aberrometer determines cylindrical
error with high accuracy, but is not sufficient for
astigmatism-free refractive correction. This is because
conventional wavefront aberrometers do not provide a reliable
measurement of spherical focus power for setting an eye to its far
accommodation point, and do not contain a mechanism to precisely
link the cylindrical axis measured in an objective refractor to the
cylindrical axis in a phoroptor for a subjective refraction or an
ophthalmic lens.
[0102] FIG. 9 shows an improved objective refractor system for a
refractive correction. The system comprises an objective refraction
device 90 for measuring refractive errors of an eye including at
least a cylindrical power, a cylindrical axis, and a spherical
focus error without any subjective response, and a mechanism for
aligning orientation of an eye to a predetermined direction in the
objective refractive device or for recording the facial orientation
of an eye during an objective refraction 92.
[0103] In one embodiment, the objective refraction device 90 is an
objective aberrometer that measures wavefront slopes across the
pupil of an eye. The wavefront aberrometer provides at least a
spherical focus power, a cylindrical power, a cylindrical axis, and
an optional spherical aberration of an eye to storage element 91.
The focus power and optional spherical aberration are available on
output devices 95 and 94 respectively.
[0104] The mechanism for aligning or recording orientation of an
eye 92 in one embodiment allows changing relative orientation of an
eye to a predetermined direction in the objective refraction
device, and provides a visual aid for setting up the relative
orientation between the refraction device and the eye under test.
In combination with the data in storage element 91, the objective
refractor system is able to output a cylindrical power and
cylindrical axis in reference to the alignment mark or recorded
image in output device 93.
[0105] The mechanism for aligning or recording facial orientation
of an eye 92 in one embodiment uses a digital camera to record at
least a portion of a human face. The human face may include a
computer-generated (via the measuring station) alignment mark, in
the form of a frame for a spectacle lens without a refractive
element.
[0106] In another embodiment, the objective refraction device can
further provide total wave aberration of an eye 96, and vision
diagnosis 98 based on the total wave aberration, data from a
refractive correction, and a residual wave aberration 97, wherein
the refractive correction includes a spherical focus power, a
cylindrical power, a cylindrical axis, and an optional spherical
aberration.
An Improved Manifest Refraction for Refractive Corrections
[0107] With the improved phoroptor and wavefront aberrometer
provided as part of the measuring station according to the present
disclosure, an improved method of manifest refraction for
astigmatism-free customized refractive correction is provided. The
method comprises of the following steps. First, an artificial
registration mark is placed on a human face. Second, an objective
estimation of the eye's focus error, cylindrical power, and
cylindrical axis is obtained using an objective refractor. The
focus power from the objective refraction has a resolution of 0.25
D and the cylindrical power has a resolution finer than 0.25 D,
e.g. 0.10D or 0.025 D. The objective refractor is preferably a
wavefront aberrometer. Third, orientation information of an eye in
reference to the objective refractor is stored based on the
artificial mark placed on the face. Fourth, before performing
subjective refraction with a phoroptor, the tested eye in a
phoroptor is aligned or checked based on the stored orientation
information of an eye. Fifth, the measuring station dials in a
cylindrical correction matching the obtained cylindrical power and
cylindrical axis from the objective refractor. Sixth, a plurality
of spherical corrections in addition to the dialed-in cylindrical
correction is presented to the patient by the station. A revised
focus power is obtained as an improvement over the objectively
measured focus error to offer an optimized correction of an eye for
far vision. Seventh, refractive correction data for manufacture of
an ophthalmic lens is generated by combining the objectively
determined cylindrical refractive power and axis and the
subjectively revised focus power.
Refraction Systems for Remote and Subjective Measurement of Human
Eyes
[0108] FIG. 10a shows a schematic diagram of an exemplary
subjective system 1000 for remote measurement of refractive errors
in an eye. In one embodiment, the subjective system 1000 includes
1) a data entry module 1011 capable of obtaining a refractive data
of an eye that include a spherical focus, an astigmatism having a
cylinder power and a cylinder angle; 2) an astigmatism module 1012
configured for the correction of an astigmatism imported from the
data entry module 1011; 3) a spherical module 1013 for providing a
plurality of focus powers for the subjective determination of
myopia, hyperopia and presbyopia; 4) a manual control module 1014
connected to the spherical module 1013 for the adjustment of the
spherical module 1013, 5) a controller 1015 configured to enable
the manual control module 1014 for manual and incremental
adjustment of focus power and to enable the astigmatism module 1012
to dial-in imported astigmatism data automatically, where the
controller 1015 includes a control board and a digital processor;
6) an output module 1016 configured to present a refractive
prescription in the form of printing, displaying, or exporting; and
7) a module of remote control 1017 configured for controlling the
refraction system at a location away from the system through a
communication network connection 1018. In some embodiments, the
manual control module 1014 is configured to be accessible to the
patient for self-adjustment. The amount for incremental adjusting
of focus power may be 0.25D or 0.125D, and the focus power can be
increased or decreased.
[0109] Unlike traditional phoroptors, shown in FIG. 10b, that are
designed for subjective optimization of all three independent
parameters (a spherical power 1021, a cylinder power 1022 and a
cylinder angle 1023) by an examiner, the system in the present
disclosure allows subjective optimization of spherical power only.
Eliminating two out of three independent parameters in the
subjective refraction process not only reduces examination time
dramatically, but also makes the final prescription of eyeglasses
unique and independent of the examiners. In traditional subjective
refraction, because all three parameters have an impact on vision
at the same time, there are many possible combinations of a focus
power, a cylinder power, and a cylinder angle that can yield the
same visual acuity. Therefore, skills and experience of the
individual examiner determines the best corrected acuity and
quality of vision for the patients.
[0110] The system in the present disclosure relies on knowing
astigmatism in an eye before a subjective refraction. It is
well-known that all aberrations in an eye, including astigmatism,
spherical aberration and coma, can be determined objectively from a
wavefront sensor for the eye. Astigmatism (cylinder power and
cylinder axis) of an eye can be precisely determined by objectively
optimizing retinal image quality of an eye from all the aberrations
obtained from a wavefront measurement. In one aspect, the
determination of astigmatism is objective and it does not depend on
skills and experience of an examiner as well as not depending on
the quality of patient feedback in the subjective refraction. In
another aspect, the astigmatism obtained from a wavefront sensor
may be far more accurate than those from a subjective refraction
because the objective optimization is performed by a computer. In
yet another aspect, accuracy in determining an eye's astigmatism
from a wavefront sensor will be about 0.05D, much finer than 0.25D
in subjective refraction. In still another aspect, for the
astigmatic correction, the data entry module in the present
disclosure is no longer limited by the manual and incremental
adjustment of 0.25D with a conventional phoroptor in the prior art,
and it allows importing cylinder power as fine as 0.01D. Therefore,
the precision and resolution of the cylinder correction in the
present methods and systems will be much finer than that with
conventional phoroptors.
[0111] The data entry module 1011 of FIG. 10a in one embodiment can
be achieved with a manual importing device such as a keyboard, a
mouse, a pointing device, or a touch screen. The data entry to the
data entry module 1011 in other embodiments can also be achieved by
reading an electronic file that contains refraction data of an eye
from a storage device, a file in a remote computer system, or a
file from a network connection. This file can also be obtained from
a patient record of historical measurements, or obtained by
measuring a pair of existing glasses with a lensometer as well.
[0112] Once astigmatism of an eye is precisely determined and
entered in the system, the astigmatism module 1012 is configured
such that manual and incremental adjustment to the cylindrical
power and cylindrical angle for the combined lenses is excluded.
This exclusion of cylindrical power and cylindrical angle is
completely different from conventional phoroptors.
[0113] Because the subjective refraction system in the present
disclosure provides fast, precise, and unique prescription of an
eye, and it can be configured for remote measurement through a
network such as the internet. The remote control system provides
the following functionalities: 1) remote data entry, 2) remote
adjustment of the spherical module 1013, and 3) remote voice/video
communication between the patient at an examination location and
the examiner away from the refraction system at the examination
location. In one embodiment, the module of remote control 1017,
connected to the refraction system through an electronic network
1018, includes at least one of i) a remote control of spherical
power 1017a, which can include a data module for data entry and
transfer, ii) a module for voice communication 1017b between the
human subject and the examiner, and iii) a module for video
communication 1017c for real-time monitoring of the refraction
process or for communication between the patient and the
examiner.
[0114] In yet another aspect, differing from traditional
phoroptors, the refractive prescription from the subjective system
in the present disclosure includes a spherical power based on
subjective response for different settings of lenses in the
spherical module, and a cylinder power and a cylinder angle that is
not optimized by subjective refraction.
[0115] The subjective system in the present disclosure can be
further configured such that the astigmatism module 1012 includes
two independent astigmatism modules, and the spherical module 1013
includes two independent spherical modules, for testing two eyes of
the human subject. The subjective system can also include a prism
module 1019 for the measurement of prism offsets between two
eyes.
[0116] In one aspect, the subjective system in the present
disclosure is further configured with a transportation system for
mobile operation. The transportation system may be, for example, a
van or vehicle large enough for setting-up refraction related
systems and devices.
[0117] In another aspect, the subjective system in the present
disclosure can be further configured with one or more input modules
1020 to accept payment information and delivery information from an
individual, and/or to receive information of frames for eyeglasses
or sunglasses. Input module 1020 may also be configured as a camera
to take a picture of the human subject with or without the selected
frames.
Refraction Systems for Remote and Objective Measurement of Human
Eyes
[0118] A wavefront sensor for human eyes measures all aberrrations
in the eye without any subjective feedback from patients or
subjective intervention from an examiner, and is therefore an
objective system. In the present disclosure, a wavefront sensor for
remote measurement of human eyes for the prescription of eyeglasses
and sunglasses is described.
[0119] FIG. 11a shows a schematic diagram of an exemplary objective
system 1100 for remote measurement of refractive error in the eye
according to some embodiments. The system 1100 includes 1) a light
source 1121 configured to produce a compact image at a retina of an
eye; 2) an optical relay 1122 that reproduces a wavefront emerging
from the eye due to reflected light from the retina to a
measurement plane away from the eye; 3) a wavefront sensor 1123 at
the measurement plane, including a wavefront sampling device and a
digital image module or device, to record images of a wavefront
that passes through the wavefront sampling device; 4) a digital
processor 1124 configured to take a sequence of wavefront
measurements at one time; 5) a display module 1125 for displaying
wavefront images with automatic detections of sampling points of
the wavefront sampling device in wavefront sensor 1123, 6) a
real-time measurement intervention module 1126 for accepting or
rejecting one or more wavefront measurement(s); 7) a data
consolidation module 1127 for calculating a spherical power and an
astigmatism (cylinder power and cylinder angle) based on a
statistical analysis from a plurality of accepted measurements; 8)
an output module 1128 configured to communicate a refractive
prescription, including a focus power, a cylinder power and a
cylinder angle; 9) a module of remote control 1129 that allows the
wavefront system 1100 to be operated by an examiner at a location
away from the wavefront system; and 10) a module for eye
positioning 1130 with motion control.
[0120] It is well known that aberrations in human eyes are not
static and change from moment to moment due to changes in tear
film, variation in pupil sizes, and micro-fluctuation of
accommodation. For prescription of eyeglasses, one set of focus
power, cylinder power and cylinder angle is provided based on a
number of wavefront measurements of the eye over a period of time.
Differing from conventional wavefront sensors for the eye in the
prior art, which is also known as an aberrometer 1150 as shown in
FIG. 11b, the wavefront sensor in the present disclosure is
designed specifically for the prescription of eyeglasses.
TABLE-US-00001 TABLE 1 Comparision of wavefront systems for the eye
Wavefront sensor Wavefront sensor (Conventional) of the present
disclosure Objective All aberrations in an eye Data for eyeglasses
prescription only Measurement One measurement at a time A plurality
of measurements for changes in Required aberrations over time
Real-time data No, each measurement by Yes, bad measurements are
excluded for validation itself is an event the prescription of
eyeglasses Real-time data No Yes, consolidation from a plurality of
consolidation measurements is required Data output One measurement
of all Consolidated data for a prescription of aberrations
including spherical eyeglasses: spherical power, and power,
astigmatism, spherical astigmatism only for prescription of
aberration, coma, etc. eyeglasses
[0121] Table 1 shows fundamental differences between aberrometers
known in the art and the present wavefront refraction system. For
obtaining one set of refraction data for eyeglasses, a plurality of
measurements of the aberrations in an eye is taken at one time,
such as over several seconds. Data validation is performed by
accepting good measurements and eliminating poor measurements that
can be seen from the wavefront images along with the analysis
results. The refraction data for each accepted measurement is
determined, and produces a consolidated refraction data of a
spherical power and an astigmatism (a cylinder power and a cylinder
angle) from a plurality of accepted measurements. Differing from
the conventional wavefront sensor known in the art, the output of
the present wavefront refraction system for eyeglasses contains
only a spherical power and an astigmatism having a cylinder power
and a cylinder axis.
[0122] In one embodiment, the wavefront system 1100 is configured
to take a sequence of wavefront measurements at one time, which
involves a) storing a plurality of wavefront images of the
wavefront sensor into a memory unit, b) providing automatic
detections of sampling points of the wavefront sensor, c)
calculating wavefront slopes across a pupil of the eye, and d)
determining wave aberration of the eye that includes at least a
focus error, an astigmatism, and a spherical aberration, and e)
displaying wavefront images (e.g., display module 1125) with
automatic detections of sampling points of the wavefront sensor.
The steps (b)-(d) (i.e., providing, calculating and determining)
may be performed by digital processor 1124. The real-time
measurement intervention module 1126 in the present system is
configured to allow an examiner or other qualified optical
professional to validate and accept a plurality of wavefront
measurements. In one embodiment, the real-time measurement
intervention module 1126 comprises a pointing device enable the
examiner to submit input for rejecting an invalid measurement in a
sequence of wavefront measurements due to i) errors in automatic
identification of image analysis, ii) inadequate pupil size for
wavefront measurements, and iii) poor image quality of the
wavefront sensor due to tear films or blinking eyes. The data
consolidation module 1127 is configured for calculating a spherical
power and an astigmatism (cylinder power and cylinder angle) based
on a statistical analysis from the accepted measurements provided
through the measurement intervention module 1126.
[0123] Different from aberrometers in the prior art, the wavefront
system in the present disclosure is further configured for remote
operation so that the wavefront system can be operated by an
examiner at a location away from the wavefront system. The remote
control module 1129 is used for i) data communication between the
digital processor 1124 for the wavefront sensor 1123 and a control
system 1131 away from the wavefront system 1100, and ii) remote
voice 1132/video 1133 communication between the patient at an
examination location and the examiner away from the wavefront
sensor 1123. In one embodiment, the module of remote control 1129,
connected to the wavefront sensor 1123 through an electronic
network 1134, comprises at least one of 1) a data module 1131 for
data entry and transfer, 2) a module for voice communication 1132
between the human subject and an examiner, and 3) a video module
1133 for real-time monitoring of the refraction process or for
communication between the patient and an examiner.
[0124] The wavefront system in the present disclosure is further
configured to include a module for motorized eye positioning system
1130. In one embodiment, the motorized eye positioning system
includes a head rest, a motion control system for positioning the
head rest at a plurality of positions, a camera system for
real-time monitoring of the position of the eye, and a motion
control system controlled by the digital computer 1124. In some
embodiments, the camera system monitors the relative position
between the eye and an optical axis of the system.
[0125] The output module 1128 of the wavefront system may be
further configured to include a data communication module for
transferring a refractive prescription in the form of printing,
displaying, or exporting. In one embodiment, the data communication
includes at least one of: a) generating a file of the prescription
in a storage device, b) sending a file of the prescription through
a network communication to another device, and c) communicating
refraction data and, in some embodiments, patient information to a
phoroptor.
[0126] In yet another embodiment, the wavefront sensor can be
generalized to any objective refraction device that generates
objective measurement of a focus power, and an astigmatism having
cylinder power and a cylinder angle.
[0127] FIG. 12 shows a schematic diagram for such a generalized
system 1200 according to an embodiment. System 1200 includes 1) a
module for motion-controlled (e.g., motorized) eye positioning 1231
that may include a head rest, a motion control system for
positioning the head rest at a plurality of positions, and a camera
system for real-time monitoring of the relative position between
the eye and an optical axis of the refraction system; 2) an
objective refraction device 1232 for measuring refractive errors of
an eye that includes a cylinder power, a cylinder angle, and a
spherical power; 3) a digital processor 1233 configured for the
control of eye positioning module 1231 and the objective refraction
device 1232, 4) a display module 1234 for displaying results of a
plurality of measurements 1235; 5) a data consolidation module 1236
for generating one set of refraction data that includes a spherical
power, and an astigmatism having a cylinder power and a cylinder
angle; 6) a module of remote control 1237 for an examiner to
remotely control the digital processor 1233 away from the
refraction system, which is connected to the refraction system
through an electronic network 1238; and 7) an output module 1239
configured to present a refractive prescription in the form of
printing, displaying, or exporting. The objective refraction device
1232 and motorized eye positioning device 1231 have remote access
by the module of remote control 1237.
Integrated Systems for Remote Measurement of Refractive Errors in
Human Eyes
[0128] Combining the objective systems in FIG. 11a or FIG. 12 with
the subjective system in FIG. 10a will produce a more effective
integrated system for remote measurement of refractive errors in
the human eye. FIG. 13 shows a exemplary schematic diagram of such
an integrated system 1300.
[0129] The integrated system 1300 includes: 1) a wavefront sensor
module 1341 for the eye for objective measurement of the eye's
refractive errors; 2) a refraction correction module 1342 for the
correction of determined astigmatism from the wavefront sensor
module 1341 and subjective determination of a spherical power; 3) a
module for motorized eye positioning 1343 that includes a head
rest, a motion control system for positioning the head rest at a
plurality of positions, and a camera system for real-time
monitoring of eye position; 4) a digital processor 1344 configured
for the control of the refraction correction module 1342, the head
position module 1343, and the wavefront sensor module 1341; 5) a
display module 1345 for the digital processor 1344; 6) an output
module 1346 configured to present a refractive prescription in the
form of printing, displaying, or exporting; and 7) a module of
remote control 1347 for an examiner to remotely control the digital
computer away from the refraction system. The module of remote
control 1347 is connected to the refraction system 1301 through an
electronic network 1348 and includes at least one of i) remote
access 1347a for the digital processor 1344, including a data
module for data entry and transfer, ii) a module for voice
communication 1347b between the human subject and an examiner, and
iii) a video module 1347c for real-time monitoring of the
refraction process or for communication between the patient and an
examiner.
[0130] In one embodiment, wavefront sensor module 1341 includes 1)
a light source configured to produce a compact image at a retina of
an eye; 2) an optical relay that reproduces a wavefront emerging
from the eye due to reflected light from the retina to a
measurement plane away from the eye; and 3) a wavefront sensor at
the measurement plane, including a wavefront sampling device and a
digital image module, to record images of a wavefront that passes
through the wavefront sampling device. Digital processor 1344
performs data analysis for wavefront sensor 1341. In some
embodiments, the light source is configured to produce a compact
image at the retina, where reflected light from the retina
generates an outgoing wavefront in front of a cornea of the eye
from a reflection of the retina.
[0131] The digital processor 1344 takes a sequence of wavefront
measurements at one time, which involves a) storing multiple
wavefront images into a memory unit, b) providing automatic
detections of sampling points of the wavefront sensor, c)
calculating wavefront slopes across a pupil of the eye, and d)
determining a wave aberration of the eye that includes at least a
focus error, an astigmatism, and a spherical aberration.
[0132] The refraction correction module 1342 includes an
astigmatism module and a spherical module. The astigmatism module
is configured such that manual and incremental adjustment to the
astigmatism module is excluded and an astigmatic correction,
including both cylinder power and cylinder angle is automatically
controlled based on the obtained objective measurement from each
eye of the individual. The spherical module of refraction
correction module 1342 is configured for manual and incremental
adjustment for the spherical power of the refraction correction
module. In some embodiments, selection and arrangement of
cylindrical lenses are determined by the astigmatism obtained from
the digital processor/computer and the wavefront sensor.
E-Commerce Methods for Delivering Eyeglasses Over the Internet
[0133] In today's eyeglass industry, at least one optometrist in
the United States or one optician in some country is needed in one
store location even though about 3 pairs of eyeglasses are sold in
each store location on average. This leads to many problems for the
eyeglass industry. First, having one examiner--that is, an
optometrist or optician--in one store is ineffective and expensive
for a business because the optometrist or optician may not perform
any eye examination if no eyeglasses are sold in a particular day.
Second, the skills and experience of the optometrists (opticians)
differ from person to person. People will get a poor vision
correction if their eyes are examined by a low-quality optometrist.
For eyes in complicated scenarios, having one optometrist in one
store makes it difficult to get a second opinion if the optometrist
is not experienced or skilled. Third, for a franchise store of
eyeglasses, there is no uniform control of quality because
refraction of human eyes is empirical and examiner-dependent, and
cannot be quantitatively standardized.
[0134] These problems lead to expensive eyeglasses, such as about
US$200 to $700 for a pair of single vision eyeglasses and US$400 to
$1000 for progressive eyeglasses, and many unsatisfied customers
with new eyeglasses.
[0135] To address issues of inefficiency and poor quality of vision
correction, an e-commerce system and method is described for
delivering eyeglasses in the present disclosure. First, in FIG. 14,
measuring stations 1451, which are configured for remote
measurement of refractive errors of eyes of an individual, are
placed in shops spread in different geographic locations. In some
embodiments there may be one measuring station 1451 in a single
location, while in other embodiments, there may be more than one
measuring station 1451 in various geographic locations. These
measuring stations 1451 are connected to a network 1455 such as an
internet connection. Second, one or more qualified examiner(s) are
organized in a centralized refraction center 1452 away from the
measuring stations at shops, and the examiners perform measurement
of refractive errors in eyes of an individual. One examiner can
operate measurement stations in a number of stores, and many
examiners can contribute for determining prescription data for one
patient in complicated situations. Third, correction data are
generated and transmitted through the network 1455 to a
manufacturing center or facility 1453. In some embodiments the
manufacturing center 1453 may be a centralized facility, while in
other embodiments the manufacturing center 1453 can include more
than one facility. The correction data include an astigmatism
having a cylinder power and a cylinder angle, and a spherical
power, and they can further include the pupil distance between two
eyes of an individual, data of frames for the eyeglasses 1454
(i.e., a digital system for eyeglass frames), and delivery
information of the eyeglass shops and of the individual patient.
Fourth, a pair of eyeglasses is manufactured and assembled in the
manufacturing facility 1453 based on the transmitted data. Fifth,
manufactured eyeglasses are delivered from the manufacturing center
1453 to the individual or eyeglass shops 1451 based on delivery
information received from the network 1455.
[0136] The e-commerce approach has many advantages. First, it
solves the problem of inefficiency because one optical examiner
(e.g., optometrist or optician) in the central examination center
1452 can operate refraction systems in a number of stores. Second,
it solves the problem of uniform quality control because the
refraction data is not generated by one examiner in an local store,
but rather by examiners in a centralized facility under strict
rules for process control. Expert opinions in a complicated
scenario can be formed by a group of optometrists in one
centralized facility. By solving the inequality problem from store
to store, one can build a franchise business for eyeglasses much
more effectively. Third, this e-commerce approach paves the way for
on-line based business because all data are digitally processed and
digital custom eyeglasses can be delivered to customer at low cost.
Finally, improving efficiency and custom satisfaction using the
present methods can lead to better and less expensive
eyeglasses.
[0137] The measuring stations for remote measurement of refractive
errors of eyes of an individual are configured to: 1) obtain an
objective measurement of refractive errors of each eye of the
individual with an objective device like the one described in FIG.
11a, 2) determine a spherical power of an eye using a subjective
system like the one described in FIG. 10a, 3) generate a refractive
correction based on the astigmatism from the objective measurement,
and the spherical power from the subjective system, and 4) provide
communication between examiners and patients based on voice and
video communication through an electronic connection. For example,
an objective refraction device may include an interface configured
to be coupled to a phoroptor for the subjective determination of a
spherical power of an eye. In some embodiments, a focus power of
each eye may be determined through subjective refraction, wherein
the subjective refraction involves subjective responses in reading
the acuity chart from the individual to a plurality of focus powers
or a subjective decision made by the examiner based on network
communication between the examiner and the individual.
[0138] In some embodiments, the remote measuring stations can be
one or a combination of the systems shown in FIG. 10a, FIG. 11a,
FIG. 12, FIG. 13 and FIG. 14.
[0139] In one embodiment, the personnel in the eyeglass shops
according to the present disclosure are not examiners qualified or
certified for eye refraction according to the laws or the
regulations--that is, they are uncertified as examiners for eye
refraction. Instead, the personnel are responsible for helping
customers for the frame selection, accepting payment information
from the individual, recording delivery information from the
individual, and taking measurements such as pupil distance and
pupil positions within a selected frame.
[0140] In one embodiment, the remote measuring stations further
include selection of a frame for eyeglasses from an electronic
system connected to the network, where selection of a frame
involves a camera or digital imaging system used for taking a
picture of an individual. Thus, the digital imaging system enables
the individual to view an image of themself with and/or without the
selected eyeglass or sunglass frames.
[0141] In yet another embodiment, an e-commerce method for
delivering eyeglasses is configured for a franchise business, where
all eyeglasses shops in different geographic locations use one
standardized protocol for measuring human eyes, generating
prescription data, manufacturing lenses, mounting lenses into
frames, and delivering eyeglasses to customers.
[0142] FIG. 15 illustrates a flowchart 1500 of an exemplary
embodiment of an electronic commerce method for the system of FIG.
14. In step 1510, a measuring station for remote measurement of
refractive errors of eyes of an individual is placed in a first
eyeglass shop in a first geographic location, where the measuring
station is connected to a network. In some embodiments, there may
be a plurality of measuring stations placed in eyeglass shops that
are in different geographic locations from each other. In step
1520, refractive errors in the eyes of the individual are
determined by an examiner in a centralized facility away from the
first eyeglass shop through the network, where the examiner is a
certified optical examiner according to laws or regulations. In
step 1530, correction data for making a pair of eyeglasses is
generated, where the correction data is based on the refractive
errors, the correction data including a spherical power, and an
astigmatism having a cylinder power and a cylinder angle. The
correction data can further include one or more of: a pupil
distance between the eyes of the individual, data about frames for
the eyeglasses, and delivery information of the eyeglass shops
and/or of the individual. In step 1540, the correction data is
transmitted through the network. In step 1550, the pair of
eyeglasses is manufactured in a manufacturing facility, the
manufacturing being based on the correction data transmitted
through the network. In step 1560, the manufactured eyeglasses are
delivered to the individual or to the eyeglass shop based on
delivery information received from the network.
[0143] While the specification has been described in detail with
respect to specific embodiments, it will be appreciated that those
skilled in the art, upon attaining an understanding of the
foregoing, may readily conceive of alterations to, variations of,
and equivalents to these embodiments. These and other modifications
and variations may be practiced by those skilled in the art,
without departing from the scope of the present disclosure, which
is more particularly set forth in the appended claims. Furthermore,
those skilled in the art will appreciate that the foregoing
description is by way of example only, and is not intended to limit
the disclosure.
* * * * *