U.S. patent application number 15/955812 was filed with the patent office on 2019-10-03 for optical lens.
The applicant listed for this patent is HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to CHUN-CHENG KO, MING-LIN LEE.
Application Number | 20190302413 15/955812 |
Document ID | / |
Family ID | 67909127 |
Filed Date | 2019-10-03 |
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United States Patent
Application |
20190302413 |
Kind Code |
A1 |
KO; CHUN-CHENG ; et
al. |
October 3, 2019 |
OPTICAL LENS
Abstract
An optical lens of the present disclosure assembly includes, in
order from an object side to an image side, a first lens element, a
second lens element, a third lens element, a fourth lens element, a
fifth lens element, a sixth lens element, an optical filter and an
optical sensor. The first lens element, the fourth lens element and
the fifth lens element each have positive power. The second lens
element, the third lens element and the sixth lens element each
have negative power.
Inventors: |
KO; CHUN-CHENG; (New Taipei,
TW) ; LEE; MING-LIN; (New Taipei, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HON HAI PRECISION INDUSTRY CO., LTD. |
New Taipei |
|
TW |
|
|
Family ID: |
67909127 |
Appl. No.: |
15/955812 |
Filed: |
April 18, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62651063 |
Mar 30, 2018 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02B 9/62 20130101; G02B
13/0045 20130101 |
International
Class: |
G02B 13/00 20060101
G02B013/00; G02B 9/62 20060101 G02B009/62 |
Claims
1. An optical lens having an optical axis, the optical lens
comprising in order from an object side of the optical lens to an
image side of the optical lens: a first lens element having a first
surface and second surface opposite to the first surface; a second
lens element having a third surface and a fourth surface; a third
lens element having a fifth surface and a sixth surface; a fourth
lens element having a seventh surface and an eighth surface; a
fifth lens element having a ninth surface and a tenth surface; a
sixth lens element having an eleventh surface and a twelfth
surface; and an optical sensor; wherein the optical lens satisfies
the following formula:
D/TTL>1.32,D/L>1.22,0.017>|Z/Y|.gtoreq.0,8.35>D/(2*Y)>8.09-
; wherein D is a diameter of the maximum imaging circle, TTL is a
length along the optical axis defined between the first surface and
the optical sensor, L is an effective diameter of the twelfth
surface, Z is a length between the lowest sag position and center
position on the ninth surface along the axis direction, Y is a
vertically height defined between the maximum sag of the ninth
surface and the optical axis.
2. The optical lens of claim 1, wherein the optical lens further
comprises an aperture and an optical filter, the aperture is
mounted in front of the first lens and respective to the object
side, the optical filter is located between the sixth lens element
and the optical sensor.
3. The optical lens of claim 2, wherein the optical filter has a
front surface and a rear surface, the front surface and the rear
surface are flat planes.
4. The optical lens of claim 2, wherein the first lens element, the
fourth lens element and the fifth lens element each have positive
power, the second lens element, the third lens element and the
sixth lens element each have negative power.
5. The optical lens of claim 4, wherein the first surface is convex
on the object side, the second surface is concave on the image
side, the third surface is convex on the object side, the fourth
surface is concave on the image side, the fifth surface is concave
on the object side, the sixth surface is convex on the image side,
the seventh surface is concave on the object side, the eight
surface is convex on the image side, the ninth surface is concave
on the object side, the tenth surface is convex on the image side,
the eleventh surface is concave on the object side, a center of the
twelfth surface is concave on the image side, an edge of the
twelfth surface is convex on the image side.
6. The optical lens of claim 2, wherein the optical lens satisfies
the formula: 0.67>|G4R1/F4|>|G1R1/F1|>|G2R2/F2|>0.27,
wherein G1R1 is the radius of curvature of the first surface, G2R2
is the radius of curvature of the fourth surface, G4R1 is the
radius of curvature of the seventh surface, F1 is the focal length
of the first lens element, F2 is the focal length of the second
lens element, F4 is the focal length of the fourth lens
element.
7. The optical lens of claim 6, wherein the optical lens satisfies
the formula: 3.84>|G4R2/F4|>|G1R2/F1|>|G2R1/F2|>0.73,
wherein G4R2 is the radius of the curvature of the eighth surface,
G1R2 is the radius of the curvature of the second surface, G2R1 is
the radius of curvature of the third surface.
8. The optical lens of claim 7, wherein the optical lens satisfies
the formula: G5R1/F5<G6R2/F6, |G5R2/F5|<|G6R1/F6|, wherein
G5R1 is the radius of curvature of the ninth surface, G5R2 is the
radius of curvature of the tenth surface, G6R1 is radius of
curvature of the eleventh surface, G6R2 is the radius of curvature
of the twelfth surface, F5 is the focal length of the fifth lens
element, F6 is the focal length of the sixth lens element.
9. The optical lens of claim 8, wherein the optical lens satisfies
the formula: G1R1/F1>0.33, G1R2/F1<2.05, G2R1/F2<-0.73,
G2R2/F2<-0.27.
10. The optical lens of claim 9, wherein the optical lens satisfies
the formula: G4R1/F4<0.67,G4R2/F4>3.55.
11. The optical lens of claim 10, wherein the optical lens
satisfies the formula: G5R1/F5<-13.70,G5R2/F5<-0.42.
12. The optical lens of claim 11, wherein the optical lens
satisfies the formula: 8.70>G6R1/F6>-16.58,
G6R2/F6<-0.43.
13. The optical lens of claim 12, wherein the optical lens
satisfies the formula: Vd1>42, Vd3>42, Vd5>42, Vd6>42,
Vd2<33, Vd4<33, wherein Vd1 is the Abbe number of the first
lens element, Vd2 is the Abbe number of the second lens element,
Vd3 is the Abbe number of the third lens element, Vd4 is the Abbe
number of the fourth lens element, Vd5 is the Abbe number of the
fifth lens element, Vd6 is the Abbe number of the sixth lens
element.
Description
FIELD
[0001] The subject matter herein generally relates to a lens,
especially, relates to an optical lens.
BACKGROUND
[0002] With the development of electrical devices, such as cell
phones and tables have become thin and light for convenient
carrying. So optical lens mounted in electrical devices is needed
to have small focal length and small effective diameter of light
exiting surface.
[0003] Further, people hope that modern electrical devices can
capture more scenery and have high image quality while taking
photos in a low light environment. So, optical lens with wide
angles are used to acquire more visible light to capture more
images, and optical lens with large aperture are used to improve
the image quality when taking photos in low light environment.
Thus, the optical lens applied in the electrical device not only
need to have small length and small effective diameter of exiting
surface, but also need to have wide view angle and large
aperture.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Implementations of the present technology will now be
described, by way of example only, with reference to the attached
figures.
[0005] FIG. 1 is a diagrammatic, cross sectional view of an optical
lens of a first embodiment.
[0006] FIG. 2 is a graph showing spherical aberration of the
optical lens of a first embodiment.
[0007] FIG. 3 is a graph showing field curvature of the optical
lens of the first embodiment.
[0008] FIG. 4 is a graph showing distortion of the optical lens of
the first embodiment.
[0009] FIG. 5 is a graph showing the modulus of the optical
transfer function (MTF) of the field view at 1/2 Nyquist frequency
of the first embodiment.
[0010] FIG. 6 is a diagrammatic, cross sectional view of an optical
lens of a second embodiment
[0011] FIG. 7 is a graph showing spherical aberration of the
optical lens of a second embodiment.
[0012] FIG. 8 is a graph showing field curvature of the optical
lens of the second embodiment.
[0013] FIG. 9 is a graph showing distortion of the optical lens of
the second embodiment.
[0014] FIG. 10 is a graph showing the field view of modulation
Transfer function (MTF) of the first embodiment.
DETAILED DESCRIPTION OF EMBODIMENTS
[0015] It will be appreciated that for simplicity and clarity of
illustration, numerous specific details are set forth in order to
provide a thorough understanding of the embodiments described
herein. However, it will be understood by those of ordinary skill
in the art that the embodiments described herein can be practiced
without these specific details. In other instances, methods,
procedures and components have not been described in detail so as
not to obscure the related relevant feature being described. Also,
the description is not to be considered as limiting the scope of
the embodiments described herein. The drawings are not necessarily
to scale and the proportions of certain parts have been exaggerated
to better illustrate details and features of the present
disclosure. The description is not to be considered as limiting the
scope of the embodiments described herein.
[0016] Several definitions that apply throughout this disclosure
will now be presented. The term "comprising" means "including, but
not necessarily limited to"; it specifically indicates open-ended
inclusion or membership in a so-described combination, group,
series and the like. The term "coupled" is defined as connected,
whether directly or indirectly through intervening components, and
is not necessarily limited to physical connections. The connection
can be such that the objects are permanently connected or
releasably connected.
[0017] Referring to FIG. 1 and FIG. 6, an optical lens 100, 100a of
the present disclosure assembly in order from an object side to an
image side includes a first lens element 10, a second lens element
20, a third lens element 30, a fourth lens element 40, a fifth lens
element 50, a sixth lens element 60, an optical filter 70 and a
optical sensor 80.
[0018] The optical lens also has an optical axis 110. The first
lens element 10, a second lens element 20, a third lens element 30,
a fourth lens element 40, a fifth lens element 50 and a sixth lens
element 60 are symmetrical about the optical axis 110.
[0019] The first lens element 10 has positive power and has a first
surface 101 and a second surface 102 opposite to the first surface
101. The first surface 101 is aspheric and convex on the object
side. The second surface 102 is aspheric. The second surface 102 is
concave on the image side.
[0020] An aperture 120 is mounted in front of the first lens
element 10 and toward the object side. The aperture 120 is located
on the optical axis 110.
[0021] The second lens element 20 has negative power. The second
lens element 20 has a third surface 201 and a fourth surface 202.
The third surface 201 is aspheric and is convex on the object side.
The fourth surface 202 is aspheric and is concave on the image
side.
[0022] The third lens element 30 has negative power. The third lens
element 30 has a fifth surface 301 and a sixth surface 302. The
fifth surface 301 is aspheric and is concave on the object side.
The sixth surface 302 is aspheric and is convex on the image
side.
[0023] The fourth lens element 40 has positive power. The fourth
lens element 40 has a seventh surface 401 and an eighth surface
402. The seventh surface 401 is concave on the object side. The
eighth surface 402 is convex on the image side.
[0024] The fifth lens element 50 has positive power. The fifth lens
element 50 has a ninth surface 501 and a tenth surface 502. Both
the ninth surface 501 and the tenth surface 502 are aspheric. The
ninth surface 501 is concave on the object side. The tenth surface
502 is convex on the image side.
[0025] The sixth lens element 60 has negative power. The sixth lens
element 60 has an eleventh surface 601 and a twelfth surface 602.
The eleventh surface 601 is aspheric and is concave on the object
side. A center of the twelfth surface 602 is concave on the image
side, an edge of the twelfth surface 602 is convex on the image
side.
[0026] The optical filter 70 has a front surface 71 and a rear
surface 72. The front surface 71 and the rear surface are flat
planes. The optical filter 70 is used to filter infrared light
throughout the sixth lens element 60.
[0027] The first surface 101, the second surface 102, the third
surface 201, the fourth surface 202, the fifth surface 301, the
sixth surface 302, the seventh surface 401, the eighth surface 402,
the ninth surface 501, the tenth surface 502, the eleventh surface
601 and the twelfth surface 602 are aspherical surfaces. The even
numbered aspherical surface are shaped according to the
formula:
Z = ch 2 1 + 1 - ( k + 1 ) c 2 h 2 + .SIGMA. A i h i ( a )
##EQU00001##
[0028] Wherein Z is aspherical surface sag of surface, h is a
surface height from the optical axis 110, c is a curvature, k is a
conic constant, and Ai are i-th order aspheric coefficients of
surface.
[0029] The optical lens satisfies the formulas:
D/TTL>1.32; (1)
D/L>1.22; (2)
0.017>|Z/Y|.gtoreq.0 (3)
8.35>D/(2*Y)>8.09 (4)
0.67>|G4R1/F4|>|G1R1/F1|>|G2R2/F2|>0.27 (5)
3.84>|G4R2/F4|>|G1R2/F1|>|G2R1/F2|>0.73 (6)
G5R1/F5<G6R2/F6 (7)
|G5R2/F5|<|G6R1/F6| (8)
G1R1/F1>0.33 (9)
G1R2/F1<2.05 (10)
G2R1/F2<-0.73 (11)
G2R2/F2<-0.27 (12)
G4R1/F4<0.67 (13)
G4R2/F4>3.55 (14)
G5R1/F5<-13.70 (15)
G5R2/F5<-0.42 (16)
8.70>G6R1/F6>-16.58 (17)
G6R2/F6<-0.43 (18)
Vd1>42,Vd3>42,Vd5>42,Vd6>42 (19)
Vd2<33,Vd4<33 (20)
[0030] Wherein, D is a diameter of the maximum imaging circle. TTL
is a length along the optical axis defined between the first
surface 101 and the optical sensor 80. L is effective diameter of
the twelfth surface 602. Z is a length between the lowest sag
position and center position on the ninth surface 501 along the
axis direction. Y is a vertical height defined between the maximum
sag of the ninth surface 501 and the optical axis 110. G1R1 is the
radius of curvature of the first surface 101. G1R2 is the radius of
the curvature of the second surface 102. G2R1 is the radius of
curvature of the third surface 201. G2R2 is the radius of curvature
of the fourth surface 202. G4R1 is the radius of curvature of the
seventh surface 401. G4R2 is the radius of the curvature of the
eighth surface 402. G5R1 is the radius of curvature of the ninth
surface 501. G5R2 is the radius of curvature of the tenth surface
502. G6R1 is radius of curvature of the eleventh surface 502. G6R2
is the radius of curvature of the twelfth surface 602. F1 is the
focal length of the first lens element 10. F2 is the focal length
of the second lens element 20. F4 is the focal length of the fourth
lens element 40. F5 is the focal length of the fifth lens element
50. F6 is the focal length of the sixth lens element 60. Vd1 is the
Abbe number of the first lens element 10. Vd2 is the Abbe number of
the second lens element 20. Vd3 is the Abbe number of the third
lens element 30. Vd4 is the Abbe number of the fourth lens element
40. Vd5 is the Abbe number of the fifth lens element 50. Vd6 is the
Abbe number of the sixth lens element 60.
[0031] The formula (1) is used to limit the length of the optical
lens. The formula (2) is used to limit the effective diameter of
exiting surface of optical lens. The formulas (3)-(4) is used to
decrease the power of the first lens element 10, the second lens
element 20, the third lens element 30 and the fourth lens element
40. The formulas (5)-(6) is used to distribute the power of the
optical lens. The formulas (7)-(8) is used to balance the power of
the fifth lens element 50 and the sixth lens element 60, and also
decrease the power of the first lens element, the second lens
element 20, the third lens element 30, the fourth lens element 40
and the fifth lens element 50. Thus, The formulas (1)-(8) makes
that the optical lens has a small length, a big aperture and a
small effective diameter of exiting surface, and also has high
image quality.
[0032] Further, the formulas (9)-(18) further improve the image
quality of the optical lens. The formulas (19)-(20) is used to
eliminate the color aberration of the optical lens.
[0033] The following embodiment specifically illustrated the
optical lens by different parameter.
[0034] Referring to tables 1-3 illustrated an optical lens of a
first embodiment. In the first embodiment, the optical lens
satisfies the parameter of tables 1-3. The symbols listed below are
used in tables 1-3.
[0035] R: a radius of curvature.
[0036] L: a distance between surfaces on the optical axis 110.
[0037] N: a refractive index of lens element.
[0038] Vd: an Abbe number.
[0039] k: a conic constant.
[0040] F: a focal length of the optical lens.
[0041] F/NO: a diameter of the aperture.
TABLE-US-00001 TABLE 1 surfaces type R(mm) L(mm) N Vd k object
Standard Infinity Infinity apeture Standard Infinity -0.41 First
surface aspheric 1.47 0.66 1.54 56.0 -0.55 Second surface aspheric
6.50 0.06 -90.00 Third surface aspheric 8.85 0.25 1.66 20.4 -16.91
Fourth surface aspheric 3.91 0.31 6.59 Fifth surface aspheric
448.98 0.40 1.54 56.0 76.01 Sixth surface aspheric 8.77 0.11 -89.81
Seventh surface aspheric 11.69 0.28 1.66 20.4 64.63 Eighth surface
aspheric 76.94 0.26 -85.00 Ninth surface aspheric -48.18 0.53 1.54
56.0 -90.00 Tenth surface aspheric -1.84 0.38 -8.27 Eleventh
surface aspheric 40.73 0.34 1.54 56.0 90.00 Twelfth surface
aspheric 1.30 0.47 -7.18 Front surface Standard Infinity 0.21 1.52
54.5 Rear surface Standard Infinity 0.33 Optical sensor Standard
--
TABLE-US-00002 TABLE 2 Aspheric First Second Third Fourth Fifth
Sixth coefficient surface surface Surface surface surface surface
A4 0.030147 -0.12659 -0.21206 -0.010919 -0.2071 -0.48617 A6
-0.04582 0.228092 0.417722 0.23983 0.256909 0.788754 A8 0.171905
-0.24426 -0.34069 -0.15065 -0.79261 -1.67863 A10 -0.27876 0.150737
0.101591 0.115072 1.3005 2.210886 A12 0.228621 -0.06182 0.068168
-0.1611 -1.13527 -1.4998 A14 -0.08268 0.006641 -0.038 0.170154
0.395961 0.371757 A16 Aspheric seventh eighth ninth tenth eleventh
twelfth coefficient surface surface surface surface surface surface
A4 -0.57449 -0.3132 0.013848 0.01172 -0.39012 -0.22951 A6 0.566205
0.072805 -0.34426 -0.18436 0.12172 0.145903 A8 -0.56031 0.33162
0.494627 0.171409 0.48382 -0.06422 A10 0.483324 -0.45649 -0.35572
-0.04987 -0.03832 0.019102 A12 -0.23585 0.22993 0.120889 -0.00159
0.009724 -0.00364 A14 0.003605 -0.03823 -0.01558 0.003141 -0.00114
0.000389 A16 -0.00041 5.20E-05 -1.73E-05
TABLE-US-00003 TABLE 3 F(mm) F/NO 2.omega. D(mm) TTL(mm) Z(mm) 3.94
1.85 78.40.degree. 6.522 4.591 -0.0023 Y(mm) L(mm) F1(mm) F2(mm)
F4(mm) F5(mm) F6(mm) 0.395 4.94 3.34 -10.71 20.60 3.49 -2.47
[0042] In the first embodiment, the longitudinal spherical
aberration graph, the field curvature graph, the distortions graph
of the optical lens are respectively shown in FIGS. 2-4. The
spherical aberration of visible light (with a wavelength between
400-700 nm) shown in FIG. 2 is within a range of -006.about.0.06
mm. The sagittal field curvature and the tangential field curvature
of visible light shown in FIG. 3 are kept in -0.065-0.065 mm. The
distortion of visible light in FIG. 4 falls with a range of 0-2%.
FIG. 5 illustrates the MTF of the field view at 1/2 Nyquist
frequency. In the exemplary embodiment, the 1/2 Nyquist frequency
is 2231p/mm. The MTF in central field view in FIG. 5 is bigger than
60%, the MTF in 0.8 field view in FIG. 5 is bigger than 40%, the
MTF between 0.8 field view and the central field view in FIG. 5 is
40%-60%, the MTF in 1.0 view in FIG. 5 is bigger than 25%.
Obviously in the second embodiment, the spherical aberration, field
curvature, distortion and MTF of the field view at 1/2 Nyquist
frequency are well controlled in the optical lens. In the first
embodiment, the spherical aberration, the field curvature, the
distortion and the field view of MTF are well controlled in the
optical lens.
[0043] Referring to tables 4-6 illustrate an optical lens of a
second embodiment. In the second embodiment, the optical lens
satisfies the parameters of Tables 6-10. The symbols listed below
are used in Tables 6-10.
[0044] R: a radius of curvature.
[0045] L: a distance between surfaces on the optical axis 110.
[0046] N: a refractive index of lens element.
[0047] V: an Abbe number of lens element.
[0048] k: a conic constant.
[0049] F: a focal length of the optical lens.
[0050] F/NO: a diameter of the aperture.
TABLE-US-00004 TABLE 4 surfaces type R(mm) L(mm) N Vd k object
Standard Infinity Infinity apeture Standard Infinity -0.41 First
surface aspheric 1.46 0.66 1.54 56.0 -0.52 Second surface aspheric
5.82 0.06 -89.95 Third surface aspheric 10.73 0.25 1.66 20.4 -52.68
Fourth surface aspheric 4.68 0.31 12.79 Fifth surface aspheric
-32.05 0.40 1.54 56.0 60.60 Sixth surface aspheric 11.57 0.11
-83.10 Seventh surface aspheric 11.79 0.28 1.66 20.4 43.51 Eighth
surface aspheric 76.13 0.26 -85.00 Ninth surface aspheric -36.41
0.53 1.54 56.0 -90.00 Tenth surface aspheric -1.84 0.38 -14.97
Eleventh surface aspheric -21.64 0.34 1.51 57.1 90.00 Twelfth
surface aspheric 1.38 0.47 -7.18 Front surface Standard Infinity
0.21 1.52 54.5 Rear surface Standard Infinity 0.33 Optical sensor
Standard --
TABLE-US-00005 TABLE 5 Aspheric First Second Third Fourth Fifth
Sixth coefficient surface surface Surface surface surface surface
A4 0.038358 -0.10617 0.038358 -0.09657 -0.23438 -0.56225 A6
-0.07119 0.081457 0.276094 0.222323 0.426495 1.136713 A8 0.206693
0.083502 0.045897 -0.06903 -1.11767 -2.30942 A10 -0.30403 -0.23193
-0.37556 0.072793 1.658505 2.878784 A12 0.238777 0.156835 0.340566
-0.2401 -1.3012 -1.91094 A14 -0.08863 -0.04089 -0.08912 0.250961
0.383941 0.479348 A16 Aspheric seventh eighth ninth tenth eleventh
twelfth coefficient surface surface surface surface surface surface
A4 -0.65393 -0.33936 -0.00373 -0.09057 -0.33728 -0.21226 A6
0.998148 0.28795 -0.16317 0.050939 0.072446 0.127634 A8 -1.47763
-0.14632 0.205342 -0.05899 0.084546 -0.0537 A10 1.42539 -0.04191
-0.16504 0.066646 -0.05436 0.015729 A12 -0.73153 0.081492 0.063477
-0.03423 0.01371 -0.00307 A14 0.120877 -0.02133 -0.00941 0.008
-0.00165 0.000342 A16 -0.00071 7.89E-05 -1.59E-05
TABLE-US-00006 TABLE 6 F(mm) F/NO 2.omega. D(mm) TTL(mm) Z(mm) 3.94
1.88 78.39.degree. 6.522 4.589 -0.0028 Y(mm) L(mm) F1(mm) F2(mm)
F4(mm) F5(mm) F6(mm) 0.398 4.92 3.39 -12.65 20.85 3.53 -2.51
[0051] In the second embodiment, the longitudinal spherical
aberration graph, the field curvature graph, and the distortion
graph of the optical lens are respectively shown in FIGS. 7-9.
[0052] The spherical aberration of visible light (with a wavelength
between 400-700 nm) shown in FIG. 7 is within a range of -0.06
mm.about.0.06 mm. The sagittal field curvature and the tangential
field curvature of visible light shown in FIG. 8 are kept in -0.065
mm-0.065 mm. The distortion of visible light in FIG. 9 falls within
a range of 0-2%. FIG. 10 illustrates the MTF of the field view at
1/2 Nyquist frequency. In the exemplary embodiment, the 1/2 Nyquist
frequency is 2231p/mm. The MTF in central field view in FIG. 10 is
bigger than 60%, the MTF in 0.8 field view in FIG. 10 is bigger
than 40%, the MTF between 0.8 field view and the central field view
in FIG. 10 is 40%-60%, the MTF in 1.0 view in FIG. 10 is bigger
than 25%. Obviously in the second embodiment, the spherical
aberration, field curvature, distortion and the field view of MTF
at 1/2 Nyquist frequency are well controlled in the optical
lens.
[0053] The embodiments shown and described above are only examples.
Many details are often found in the art such as the other features
of an optical lens. Therefore, many such details are neither shown
nor described. Even though numerous characteristics and advantages
of the present technology have been set forth in the foregoing
description, together with details of the structure and function of
the present disclosure, the disclosure is illustrative only, and
changes can be made in the detail, including in matters of shape,
size and arrangement of the parts within the principles of the
present disclosure up to, and including the full extent established
by the broad general meaning of the terms used in the claims. It
will therefore be appreciated that the embodiments described above
can be modified within the scope of the claims.
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