U.S. patent application number 17/747832 was filed with the patent office on 2022-09-01 for rotating pyramidal mirror.
The applicant listed for this patent is Seagate Technology LLC. Invention is credited to Pierre Asselin, Kevin A. Gomez, Zoran Jandric, Dan Mohr, Raghu Ambekar Ramachan Rao, Krishnan Subramanian.
Application Number | 20220276354 17/747832 |
Document ID | / |
Family ID | 1000006344812 |
Filed Date | 2022-09-01 |
United States Patent
Application |
20220276354 |
Kind Code |
A1 |
Gomez; Kevin A. ; et
al. |
September 1, 2022 |
ROTATING PYRAMIDAL MIRROR
Abstract
An apparatus includes a detector, a light source configured to
emit light, a reflecting apparatus having multiple reflective
facets, and a mirror. The reflecting apparatus is configured to
rotate around an axis and arranged to reflect the emitted light
from the light source and reflect backscattered light. The mirror
is arranged to reflect the backscattered light from the reflecting
apparatus towards the detector.
Inventors: |
Gomez; Kevin A.; (Eden
Prairie, MN) ; Jandric; Zoran; (St. Louis Park,
MN) ; Subramanian; Krishnan; (Shakopee, MN) ;
Asselin; Pierre; (Richfield, MN) ; Mohr; Dan;
(Roseville, MN) ; Rao; Raghu Ambekar Ramachan;
(Bloomington, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Seagate Technology LLC |
Fremont |
CA |
US |
|
|
Family ID: |
1000006344812 |
Appl. No.: |
17/747832 |
Filed: |
May 18, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
16206831 |
Nov 30, 2018 |
11391822 |
|
|
17747832 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01S 17/10 20130101;
G02B 26/125 20130101; G02B 26/124 20130101; G01S 7/4817 20130101;
G02B 26/101 20130101 |
International
Class: |
G01S 7/481 20060101
G01S007/481; G02B 26/10 20060101 G02B026/10; G01S 17/10 20060101
G01S017/10; G02B 26/12 20060101 G02B026/12 |
Claims
1. A system comprising: a housing at least partially encompassing
an internal cavity; a laser configured to emit pulsed light and
positioned within the internal cavity; a sensor positioned within
the internal cavity; a rotatable pyramidal mirror having multiple
reflective facets and arranged to reflect the emitted pulsed light
and backscattered light; and a mirror arranged to reflect the
backscattered light from the rotatable pyramidal mirror towards the
sensor, the mirror is positioned between the laser and the
rotatable pyramidal mirror.
2. The system of claim 1, further comprising: a lens positioned
between the laser and the mirror.
3. The system of claim 2, further comprising: a focusing lens
positioned between the mirror and the sensor.
4. The system of claim 3, wherein the mirror is a static
mirror.
5. The system of claim 4, wherein the static mirror includes an
aperture through which the emitted pulsed light passes through.
6. The system of claim 1, further comprising: a lens positioned
between the laser and the rotatable pyramidal mirror.
7. The system of claim 1, further comprising: a rotatable mirror
positioned between the laser and the rotatable pyramidal mirror and
arranged to direct the emitted pulsed light towards the rotatable
pyramidal mirror.
8. The system of claim 7, further comprising: a focusing lens
optically positioned between the rotatable pyramidal mirror and the
sensor.
9. The system of claim 7, further comprising: a first lens
optically positioned between the rotatable mirror and the rotatable
pyramidal mirror.
10. The system of claim 9, further comprising: a second lens
optically positioned between the rotatable mirror and the rotatable
pyramidal mirror.
11. The system of claim 1, wherein the sensor is positioned between
the mirror and the rotatable mirror.
12. The system of claim 1, wherein the mirror is a parabolic
mirror, the system further comprising: a rotatable mirror
positioned between the laser and the rotatable pyramidal mirror and
arranged to direct the emitted pulsed light towards the rotatable
pyramidal mirror.
13. The system of claim 12, wherein the parabolic mirror includes
an aperture, wherein the rotatable mirror is arranged to direct the
emitted pulsed light through the aperture.
14. The system of claim 1, wherein the rotatable pyramidal mirror
includes only six reflective facets.
15. An apparatus comprising: a light sensor; a laser configured to
emit light; a rotatable pyramidal mirror having multiple reflective
facets and arranged to reflect the emitted pulsed light and
backscattered light; a first lens optically positioned between the
laser and the rotatable pyramidal mirror; a second lens optically
positioned between the first lens and the rotatable pyramidal
mirror; and a mirror arranged to reflect the backscattered light
from the rotatable pyramidal mirror towards the light sensor.
16. The apparatus of claim 15, further comprising: a rotating
mirror arranged to reflect the emitted light from the laser to the
first lens.
17. The apparatus of claim 15, wherein the mirror includes an
aperture through which the emitted light passes from the laser to
the rotatable pyramidal mirror.
18. The apparatus of claim 15, further comprising: a focusing lens
positioned between the mirror and the light sensor and configured
to focus the backscattered light towards the light sensor.
19. The apparatus of claim 15, wherein the first lens and the
second lens are cylindrical lenses.
20. The apparatus of claim 19, wherein the first lens is smaller
than the second lens.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. patent application
Ser. No. 16/206,831, filed Nov. 30, 2018, which is incorporated
herein by reference in its entirety for all purposes.
SUMMARY
[0002] In certain embodiments, an apparatus includes a detector, a
light source configured to emit light, a reflecting apparatus
having multiple reflective facets, and a mirror. The reflecting
apparatus is configured to rotate around an axis and arranged to
reflect the emitted light from the light source and reflect
backscattered light. The mirror is arranged to reflect the
backscattered light from the reflecting apparatus towards the
detector.
[0003] In certain embodiments, a method for generating a light
pattern is disclosed. The method includes rotating a reflecting
apparatus having a plurality of facets. The method further includes
generating, via a light source, pulsed light. The method further
includes directing, via an optical element, the pulsed light along
to at least one of the facets. The optical element directs the
pulsed light along a line. Further, the method includes reflecting,
via the at least one of the facets, the pulsed light to create the
light pattern.
[0004] In certain embodiments, a system includes a housing
including a base member and a transparent cover that at least
partially encompass an internal cavity. The system further includes
a laser configured to emit pulsed light and positioned within the
internal cavity. The system includes a sensor positioned within the
internal cavity and a rotatable pyramidal mirror having multiple
reflective facets and arranged to reflect the emitted pulsed light
and backscattered light. Further, the system includes a mirror
arranged to reflect the backscattered light from the rotatable
pyramidal mirror towards the sensor.
[0005] While multiple embodiments are disclosed, still other
embodiments of the present invention will become apparent to those
skilled in the art from the following detailed description, which
shows and describes illustrative embodiments of the invention.
Accordingly, the drawings and detailed description are to be
regarded as illustrative in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 shows a schematic, cut-away view of a measurement
device with a rotating mirror and a curved mirror, in accordance
with certain embodiments of the present disclosure.
[0007] FIG. 2 shows a perspective view of a reflecting apparatus
and a motor, in accordance with certain embodiments of the present
disclosure.
[0008] FIG. 3 shows a schematic, perspective view of the
measurement device of FIG. 1 and an example light pattern generated
by the measurement device, in accordance with certain embodiments
of the present disclosure.
[0009] FIG. 4 shows a perspective view of a curved mirror, in
accordance with certain embodiments of the present disclosure.
[0010] FIG. 5 shows a schematic, cut-away view of a measurement
device with a lens and a curved mirror, in accordance with certain
embodiments of the present disclosure.
[0011] FIG. 6 shows a schematic, cut-away view of a measurement
device with a rotating mirror, a lens, and curved mirror, in
accordance with certain embodiments of the present disclosure.
[0012] FIG. 7 shows a schematic, cut-away view of a measurement
device with a rotating mirror and a focusing apparatus, in
accordance with certain embodiments of the present disclosure.
[0013] FIG. 8 shows a schematic, cut-away view of a measurement
device with a lens and a focusing apparatus, in accordance with
certain embodiments of the present disclosure.
[0014] FIG. 9 shows a schematic, cut-away view of a measurement
device with multiple lenses and a focusing apparatus, in accordance
with certain embodiments of the present disclosure.
[0015] While the disclosure is amenable to various modifications
and alternative forms, specific embodiments have been shown by way
of example in the drawings and are described in detail below. The
intention, however, is not to limit the disclosure to the
particular embodiments described but instead is intended to cover
all modifications, equivalents, and alternatives falling within the
scope of the appended claims.
DETAILED DESCRIPTION
[0016] Certain embodiments of the present disclosure relate to
measurement devices and techniques, particularly, measurement
devices and techniques for light detection and ranging, which is
commonly referred to as LIDAR, LADAR, etc.
[0017] Current LIDAR devices typically use a series of spinning
mirrors that steer many narrow light beams. These devices utilize a
low numerical aperture, such that only a small amount of reflected
light is received by detectors within the device. As a result,
these devices require very sensitive detectors. Certain embodiments
of the present disclosure are accordingly directed to devices and
techniques for measurement systems, such as LIDAR systems, in which
sensors with a broader range of sensitivities can be used while
still achieving accurate measurements. Further, as will be
described in more detail below, the disclosed measurement devices
include optical elements and arrangements that can be used to
generate scanning patterns of light (e.g., paths along which light
is scanned) with a large field of view using as few as one light
source and to detect backscattered light using as few as one
detector.
[0018] FIG. 1 shows a schematic of a measurement device 100 (e.g.,
a LIDAR/LADAR device) including a housing 102 with a base member
104 and a cover 106. The base member 104 and the cover 106 can be
coupled together to surround an internal cavity 108 in which
various components of the measurement device 100 are positioned. In
certain embodiments, the base member 104 and the cover 106 are
coupled together to create an air and/or water-tight seal. For
example, various gaskets or other types of sealing members can be
used to help create such seals between components of the housing
102. The base member 104 can comprise materials such as plastics
and/or metals (e.g., aluminum). The cover 106 can comprise, in
whole or in part, transparent materials such as glass or sapphire.
In certain embodiments, various components of the housing 102 is
coated with an anti-reflective coating. For simplicity, the housing
102 in FIG. 1 is shown with only the base member 104 and the cover
106, but the housing 102 can comprise any number of components that
can be assembled together to surround the internal cavity 108 and
secure components of the measurement device 100. Further, the base
member 104 may be machined, molded, or otherwise shaped to support
the components of the measurement device 100. The features of the
measurement device 100 and other measurement devices described
herein are not necessarily drawn to scale. The figures are intended
to show examples of how the features of the measurement devices can
be arranged to create scanning patterns of light that are emitted
from and scattered back to the measurement devices. For example,
the figures show how the features of the measurement devices are
physically arranged with respect to each. Further, the figures show
example arrangements of optical elements within optical paths that
create patterns of light and detect light scattered back to the
measurement devices.
[0019] The measurement device 100 includes a light source 110
(e.g., a laser), a rotatable mirror 112 (e.g., a mirror-on-a-chip,
electro-thermal-actuated mirror, or the like), a reflecting
apparatus 114 (e.g., a rotatable pyramidal-shaped mirror), a
focusing apparatus 116 (e.g., a lens or a parabolic mirror), and a
detector 118 (e.g., a sensor).
[0020] The light source 110 can be a laser (e.g., laser diodes such
as VCSELs and the like) or a light-emitting diode configured to
emit coherent light. In certain embodiments, the light source 110
emits light (e.g., coherent light) within the infrared spectrum
(e.g., 905 nm and 1515 nm frequencies are non-limiting examples)
while in other embodiments the light source 110 emits light within
the visible spectrum (e.g., 485 nm frequency as a non-limiting
example). In certain embodiments, the light source 110 is
configured to emit light in pulses.
[0021] The light emitted by the light source 110 is directed
towards the reflecting apparatus 114. The emitted light and its
direction are represented in FIG. 1 by arrows 120. In certain
embodiments, the emitted light 120 is first directed towards the
rotatable mirror 112, which reflects the light towards the
reflecting apparatus 114. The rotatable mirror 112 can be a
silicone-based Micro Electro Mechanical Systems (MEMS) mirror,
which is sometimes referred to as a mirror-on-a-chip. The rotatable
mirror 112 can rotate around an axis such that the emitted light is
scanned back and forth along a line. Put another way, the rotatable
mirror 112 can be used to steer the emitted light 120 along a line
and towards the reflecting apparatus 114. As shown in FIG. 1, the
rotatable mirror 112 is angled at a nominal angle of 45 degrees
with respect to the emitted light 120 from the light source 110
such that the emitted light 120 is reflected at a nominal angle of
90 degrees. In certain embodiments, the rotatable mirror 112 is
configured to rotate around the axis within ranges such as 1-20
degrees, 5-15 degrees, and 8-12 degrees. Using a 10-degree range of
rotation as an example, the emitted light 120 would be reflected
back and forth between angles of 85 degrees and 95 degrees as the
rotatable mirror 112 rotates back and forth within its range of
rotation. As will be described in more detail below, the range of
rotation affects the extent or displacement of the line scan
created by the rotatable mirror 112.
[0022] In certain embodiments, the emitted light 120 reflected by
the rotatable mirror 112 (which creates a line scan over time)
passes through an aperture 122 in the focusing apparatus 116
towards the reflecting apparatus 114. An exemplary reflecting
apparatus 114 is shown in FIG. 2 and can be described as a
six-sided (or hexagonal) pyramidal-shaped rotating mirror. The
reflecting apparatus 114 can be at least partially created using
three-dimensional printing, molding, and the like. The reflecting
apparatus 114 is coupled to a cylindrical-shaped motor 124 that
rotates the reflecting apparatus 114 during operation of the
measurement device 100. Increasing rotational speed of the motor
124 (and therefore the rotational speed of the reflecting apparatus
114) increases the sampling rate of the measurement device 100 but
also increases the power consumed by the measurement device 100.
The motor 124 can be a fluid-dynamic-bearing motor, a ball-bearing
motor, and the like. Although the motor 124 is shown as being
centrally positioned within the reflecting apparatus 114, the
reflecting apparatus 114 can be rotated via other means, including
means other than the motor 124 shown in FIG. 2.
[0023] The reflecting apparatus 114 comprises a plurality of
facets/faces 126A-F. Each facet 126A-F includes or otherwise
incorporates a reflective surface such as a mirror. For example, a
mirror can be attached to each facet 126A-F of the reflecting
apparatus 114. Although the reflecting apparatus 114 is shown and
described as having six facets at an approximately 45-degree angle,
the reflecting apparatus can have fewer or more facets (e.g., 3-5
facets, 7-24 facets) at different angles (e.g., 30-60 degrees). The
number of facets affects the displacement of the emitted light 120.
For example, as the reflecting apparatus 114 rotates, the emitted
light 120 directed towards the reflecting apparatus 114 will be
reflected and scanned along a line. The overall displacement of the
line is dependent on the number of facets on the reflecting
apparatus 114. When the reflecting apparatus 114 includes six
facets, 126A-F, the resulting line that the emitted light 120 is
scanned along has a displacement of sixty degrees (i.e., 360
degrees divided by the number of facets, which is six). This
displacement affects the field of view of the measurement device
100.
[0024] When the scan line created by the rotatable mirror 112 is
reflected by the rotating reflective apparatus 114, a resulting
light pattern 128 or light path is created, similar to that shown
in FIG. 3. The light pattern 128 has a vertical component 130 and a
horizontal component 132 that makeup the field of view of the
measurement device 100. The horizontal component 132 (or
displacement) portion of the light pattern 128 is created by the
rotating reflective apparatus 114, and the vertical component 130
is created by the rotatable mirror 112. When the rotatable mirror
112 rotates within a 10-degree range of angles and the reflecting
apparatus 114 includes six facets 126A-F, the vertical component
130 of the light pattern 128 is 10 degrees and the horizontal
component 132 is 60 degrees. As such, the measurement device 100
can be said to have a 10-degree by 60-degree field of view.
[0025] The emitted light is transmitted out of the housing 102
(e.g., through the translucent cover 106) of the measurement device
100 towards objects. A portion of the emitted light reflects off
the objects and returns through the cover 106. This light, referred
to as backscattered light, is represented in FIG. 1 by multiple
arrows 136 (not all of which are associated with a reference number
in FIG. 1). In certain embodiments, the backscattered light 136 is
reflected by the same facet on the reflecting apparatus 114 that
the emitted light 120 reflected against before being transmitted
out of the housing 102. After being reflected by the reflecting
apparatus 114, the backscattered light 136 is focused by the
focusing apparatus 116.
[0026] The focusing apparatus 116 is an optical element that
focuses the backscattered light 136 towards the detector 118. For
example, the focusing apparatus 116 can be a lens or a curved
mirror such as a parabolic mirror. FIG. 1 shows the focusing
apparatus 116 as a parabolic mirror with its focal point positioned
at the detector 118. FIG. 4 shows a perspective view of the
focusing apparatus 116 in the shape of a parabolic mirror extending
around a full 360 degrees. The particular shape, size, position,
and orientation of the focusing apparatus 116 in the measurement
device 100 can depend on, among other things, the position of the
detector(s) 118, where the path(s) at which backscattered light 136
is directed within the housing 102, and space constraints of the
measurement device 100.
[0027] In certain embodiments, the focusing apparatus 116 focuses
backscattered light to the detector 118, such as one or more
photodetectors/sensors arranged in one or more arrays. The detector
118 can be positioned at the focal point of the focusing apparatus
116. In response to receiving the focused backscattered light, the
detector 118 generates one or more sensing signals, which are
ultimately used to detect the distance and/or shapes of objects
that reflect the emitted light back towards the measurement device
100 and ultimately to the detector 118.
[0028] In certain embodiments, the measurement device 100 and the
other measurement devices described below can generate multiple
light patterns. For example, the measurement device 100 can include
multiple light sources or include a beam splitter to create
multiple light paths from a single light source. In such
embodiments, each light beam would be directed towards separate
facets on the reflecting apparatus 114. Using a six-faceted
reflecting apparatus 114 as an example, a measurement device that
directs light to two of the reflecting apparatus's facets would
have either a 120-degree horizontal field of view or up to two
separate 60-degree horizontal fields of view. For a 360-degree
horizontal field of view, a measurement device could include six
separate light beams (via multiple light sources and/or one or more
beam splitters) each reflecting off a separate facet of the
rotating apparatus 114.
[0029] FIG. 5 shows a measurement device 200 including a housing
202 with a base member 204 and a transparent cover 206 that can be
coupled together to surround an internal cavity 208 in which
various components of the measurement device 200 are positioned.
For simplicity, the housing 202 in FIG. 5 is shown with only the
base member 204 and the cover 206, but the housing 202 can comprise
any number of components that can be assembled together to create
the internal cavity 208 and secure components of the measurement
device 200.
[0030] The measurement device 200 includes a light source 210, a
lens 212, a reflecting apparatus 214, a focusing apparatus 216, and
a detector 218. The light source 210 can be a laser or a
light-emitting diode configured to emit coherent light. In certain
embodiments, the light source 210 emits light within the infrared
spectrum while in other embodiments the light source 210 emits
light within the visible spectrum. In certain embodiments, the
light source 210 is configured to emit light in pulses.
[0031] The light emitted by the light source 210 is directed
towards the lens 212. The emitted light and its direction is
represented in FIG. 5 by arrows 220. The lens 212 can be a
cylindrical shaped lens that converts the emitted light 220 to a
line. In certain embodiments, the lens 212 is configured to create
a line with a displacement of ranges such as 1-20 degrees, 5-15
degrees, and 8-12 degrees.
[0032] After passing through the lens 212, the emitted light 220
passes through an aperture 222 in the focusing apparatus 216
towards the reflecting apparatus 214. An example reflecting
apparatus is shown in FIG. 2 and described in more detail above
with respect to the measurement device 100 of FIG. 1. The
reflecting apparatus 214 is coupled to a device (e.g., motor 124 of
FIG. 1) that rotates the reflecting apparatus 214. The reflecting
apparatus 214 comprises a plurality of facets/faces 226. Each facet
226 comprises a reflective surface such as a mirror.
[0033] When the scan line created by the lens 212 is reflected by
the rotating reflective apparatus 214, a resulting light pattern is
created. The light pattern has a vertical component and a
horizontal component that makeup the field of view of the
measurement device 200. The horizontal component (or displacement)
portion of the light pattern is created by the rotating reflective
apparatus 214, and the vertical component is created by the lens
212. When the lens 212 creates a line with a 10-degree displacement
and the reflecting apparatus 214 includes six facets, the vertical
component of the light pattern is 10 degrees and the horizontal
component is 60 degrees. As such, the measurement device 200 can be
said to have a 10-degree by 60-degree field of view.
[0034] The emitted light is transmitted out of the housing 202
(e.g., through the translucent cover 206) of the measurement device
200 towards objects. A portion of the emitted light reflects off
the objects and returns through the cover 206. This light, referred
to as backscattered light, is represented in FIG. 5 by multiple
arrows 228 (not all of which are associated with a reference number
in FIG. 5). In certain embodiments, the backscattered light 228 is
reflected by the same facet 226 on the reflecting apparatus 214
that the emitted light 220 reflected against before being
transmitted out of the housing 202. After being reflected by the
reflecting apparatus 214, the backscattered light 228 is focused by
the focusing apparatus 216.
[0035] The focusing apparatus 216 is an optical element that
focuses the backscattered light 228 towards the detector 218. FIG.
5 shows the focusing apparatus 216 as a parabolic mirror with its
focal point positioned at the detector 218. The particular shape,
size, position, and orientation of the focusing apparatus 216 in
the measurement device 200 can depend on, among other things, the
position of the detector(s) 218, where the path(s) at which
backscattered light 228 is directed within the housing 202, and
space constraints of the measurement device 200.
[0036] In certain embodiments, the focusing apparatus 216 focuses
backscattered light to the detector 218, such as one or more
photodetectors/sensors arranged in one or more arrays. The detector
218 can be positioned at the focal point of the focusing apparatus
216. In response to receiving the focused backscattered light, the
detector 218 generates one or more sensing signals, which are
ultimately used to detect the distance and/or shapes of objects
that reflect the emitted light back towards the measurement device
200 and ultimately to the detector 218.
[0037] FIG. 6 shows a measurement device 300 including a housing
302 with a base member 304 and a transparent cover 306 that can be
coupled together to surround an internal cavity 308 in which
various components of the measurement device 300 are positioned.
For simplicity, the housing 302 in FIG. 6 is shown with only the
base member 304 and the cover 306, but the housing 302 can comprise
any number of components that can be assembled together to create
the internal cavity 308 and secure components of the measurement
device 300.
[0038] The measurement device 300 includes a light source 310, a
rotatable mirror 312, a first lens 314, a second lens 316, a
reflecting apparatus 318, a focusing apparatus 320, and a detector
322. The light source 310 can be a laser or a light-emitting diode
configured to emit coherent light. In certain embodiments, the
light source 310 emits light within the infrared spectrum while in
other embodiments the light source 310 emits light within the
visible spectrum. In certain embodiments, the light source 310 is
configured to emit light in pulses.
[0039] The emitted light is first directed towards the rotatable
mirror 312, which reflects the light towards the first lens 314,
the second lens 316, and the reflecting apparatus 318. The emitted
light and its direction are represented in FIG. 6 by arrows 324.
The rotatable mirror 312 can be a silicone-based MEMS mirror. The
rotatable mirror 312 can rotate around an axis such that the
emitted light is scanned back and forth along a line. Put another
way, the rotatable mirror 312 can be used to steer the emitted
light 324 along a line. As shown in FIG. 6, the rotatable mirror
312 is angled at a nominal angle of 45 degrees with respect to a
direction of the emitted light 324 from the light source 310 such
that the emitted light 324 is reflected at a nominal angle of 90
degrees. In certain embodiments, the rotatable mirror 312 is
configured to rotate around the axis within ranges such as 1-20
degrees, 5-15 degrees, and 8-12 degrees.
[0040] After reflecting off the rotatable mirror 312, the scanning
line of emitted light 324 is directed to the first lens 314. The
first lens 314 magnifies the emitted light, which is then directed
towards the second lens 316. The second lens 316 collimates the
magnified light, which is then directed towards the reflecting
apparatus 318. In certain embodiments, as shown in FIG. 6, the
focal point of the second lens 316 is at or near an aperture 330 of
the focusing apparatus 320. Such an arrangement allows for a
larger-sized rotatable mirror 312 and/or reduces the need for a
larger-sized aperture in the focusing apparatus 320, and therefore,
increases the amount of light focused to the detector 322.
[0041] An example reflecting apparatus is shown in FIG. 2 and
described in more detail above with respect to the measurement
device 100 of FIG. 1. The reflecting apparatus 318 is coupled to a
device (e.g., motor 124 of FIG. 1) that rotates the reflecting
apparatus 318. The reflecting apparatus 318 comprises a plurality
of facets/faces 326. Each facet 326 comprises a reflective surface
such as a mirror.
[0042] When the scan line created by the rotatable mirror 312, the
first lens 314, and the second lens 316 is reflected by the
rotating reflective apparatus 318, a resulting light pattern is
created. The light pattern has a vertical component and a
horizontal component that makeup the field of view of the
measurement device 300. The horizontal component (or displacement)
portion of the light pattern is created by the rotating reflective
apparatus 318, and the vertical component is created by the
rotatable mirror 312, the first lens 314, and the second lens 316.
When the rotatable mirror 312 rotates within a 10-degree range and
the reflecting apparatus 314 includes six facets, the vertical
component of the light pattern is 10 degrees and the horizontal
component is 60 degrees. As such, the measurement device 300 can be
said to have a 10-degree by 60-degree field of view.
[0043] The emitted light is transmitted out of the housing 302
(e.g., through the translucent cover 306) of the measurement device
300 towards objects. A portion of the emitted light reflects off
the objects and returns through the cover 306. This light, referred
to as backscattered light, is represented in FIG. 6 by multiple
arrows 328 (not all of which are associated with a reference number
in FIG. 6). In certain embodiments, the backscattered light 328 is
reflected by the same facet 326 on the reflecting apparatus 318
that the emitted light 324 reflected against before being
transmitted out of the housing 302. After being reflected by the
reflecting apparatus 318, the backscattered light 328 is focused by
the focusing apparatus 320.
[0044] The focusing apparatus 320 is an optical element that
focuses the backscattered light 328 towards the detector 322. FIG.
6 shows the focusing apparatus 320 as a parabolic mirror with its
focal point positioned at the detector 322. The particular shape,
size, position, and orientation of the focusing apparatus 320 in
the measurement device 300 can depend on, among other things, the
position of the detector(s) 322, where the path(s) at which
backscattered light 328 is directed within the housing 302, and
space constraints of the measurement device 300.
[0045] In certain embodiments, the focusing apparatus 320 focuses
backscattered light to the detector 322, such as one or more
photodetectors/sensors arranged in one or more arrays. The detector
322 can be positioned at the focal point of the focusing apparatus
320. In response to receiving the focused backscattered light, the
detector 322 generates one or more sensing signals, which are
ultimately used to detect the distance and/or shapes of objects
that reflect the emitted light back towards the measurement device
300 and ultimately to the detector 322.
[0046] FIG. 7 shows a measurement device 400 including a housing
402 with a base member 404 and a transparent cover 406 that can be
coupled together to surround an internal cavity 408 in which
various components of the measurement device 400 are positioned.
For simplicity, the housing 402 in FIG. 7 is shown with only the
base member 404 and the cover 406, but the housing 402 can comprise
any number of components that can be assembled together to create
the internal cavity 408 and secure components of the measurement
device 400.
[0047] The measurement device 400 includes a light source 410, a
rotatable mirror 412, a rotatable reflecting apparatus 414, a
static reflecting apparatus 416, a focusing apparatus 418, and a
detector 420. The light source 410 can be a laser or a
light-emitting diode configured to emit coherent light. In certain
embodiments, the light source 410 emits light within the infrared
spectrum while in other embodiments the light source 410 emits
light within the visible spectrum. In certain embodiments, the
light source 410 is configured to emit light in pulses.
[0048] The light emitted by the light source 410 is directed
towards the rotatable reflecting apparatus 414. The emitted light
and its direction are represented in FIG. 7 by arrows 422. In
certain embodiments, the emitted light 422 is first directed
towards the rotatable mirror 412, which reflects the light towards
the rotatable reflecting apparatus 414. The rotatable mirror 412
can be a silicone-based MEMS mirror. The rotatable mirror 412 can
rotate around an axis such that the emitted light is scanned back
and forth along a line. Put another way, the rotatable mirror 412
can be used to steer the emitted light 422 along a line and towards
the rotatable reflecting apparatus 414. As shown in FIG. 7, the
rotatable mirror 412 is angled at a nominal angle of 45 degrees
with respect to the emitted light 422 from the light source 410
such that the emitted light 420 is reflected at a nominal angle of
90 degrees. In certain embodiments, the rotatable mirror 412 is
configured to rotate around the axis within ranges such as 1-20
degrees, 5-15 degrees, and 8-12 degrees.
[0049] After being reflected by the rotatable mirror 412, the
emitted light 422 passes through an aperture 424 in the static
reflecting apparatus 416 towards the rotatable reflecting apparatus
414. An example reflecting apparatus is shown in FIG. 2 and
described in more detail above with respect to the measurement
device 100 of FIG. 1. The rotatable reflecting apparatus 414 is
coupled to a device (e.g., motor 124 of FIG. 1) that rotates the
rotatable reflecting apparatus 414. The rotatable reflecting
apparatus 414 comprises a plurality of facets/faces 426. Each facet
426 comprises a reflective surface such as a mirror.
[0050] When the scan line created by the rotatable mirror 412 is
reflected by the rotatable reflective apparatus 414, a resulting
light pattern or light path is created. The light pattern has a
vertical component and a horizontal component that makeup the field
of view of the measurement device 400. The horizontal component (or
displacement) portion of the light pattern is created by the
rotatable reflective apparatus 414, and the vertical component is
created by the rotatable mirror 412. When the rotatable mirror 412
rotates within a 10-degree range of angles and the rotatable
reflecting apparatus 414 includes six facets, the vertical
component of the light pattern is 10 degrees and the horizontal
component is 60 degrees. As such, the measurement device 400 can be
said to have a 10-degree by 60-degree field of view.
[0051] The emitted light 422 is transmitted out of the housing 402
(e.g., through the translucent cover 406) of the measurement device
400 towards objects. A portion of the emitted light reflects off
the objects and returns through the cover 406. This light, referred
to as backscattered light, is represented in FIG. 7 by multiple
arrows 428 (not all of which are associated with a reference number
in FIG. 7). In certain embodiments, the backscattered light 428 is
reflected by the same facet 426 on the rotatable reflecting
apparatus 414 that the emitted light 422 reflected against before
being transmitted out of the housing 402.
[0052] After being reflected by the rotatable reflecting apparatus
414, the backscattered light 428 is directed towards the static
reflecting apparatus 416. In certain embodiments, the static
reflecting apparatus 416 is a mirror (e.g., a folding mirror) that
reflects the backscattered light 428 towards the focusing apparatus
418.
[0053] The focusing apparatus 418 is an optical element that
focuses the backscattered light 428 towards the detector 420. The
focusing apparatus 418 is shown in FIG. 7 as a lens with its focal
point positioned at the detector 420. The particular shape, size,
position, and orientation of the focusing apparatus 418 in the
measurement device 400 can depend on, among other things, the
position of the detector(s) 420, where the path(s) at which
backscattered light 428 is directed within the housing 402, and
space constraints of the measurement device 400.
[0054] The focusing apparatus 418 focuses backscattered light to
the detector 420, such as one or more photodetectors/sensors
arranged in one or more arrays. In response to receiving the
focused backscattered light, the detector 420 generates one or more
sensing signals, which are ultimately used to detect the distance
and/or shapes of objects that reflect the emitted light back
towards the measurement device 400 and ultimately to the detector
420.
[0055] FIG. 8 shows a measurement device 500 including a housing
502 with a base member 504 and a transparent cover 506 that can be
coupled together to surround an internal cavity 508 in which
various components of the measurement device 200 are positioned.
For simplicity, the housing 502 in FIG. 8 is shown with only the
base member 504 and the cover 506, but the housing 502 can comprise
any number of components that can be assembled together to create
the internal cavity 508 and secure components of the measurement
device 500.
[0056] The measurement device 500 includes a light source 510, a
rotatable mirror 512, a rotatable reflecting apparatus 514, a
static reflecting apparatus 516, a focusing apparatus 518, and a
detector 4520. The light source 510 can be a laser or a
light-emitting diode configured to emit coherent light. In certain
embodiments, the light source 510 emits light within the infrared
spectrum while in other embodiments the light source 510 emits
light within the visible spectrum. In certain embodiments, the
light source 510 is configured to emit light in pulses.
[0057] The light emitted by the light source 510 is directed
towards the lens 512. The emitted light and its direction is
represented in FIG. 8 by arrows 522. The lens 512 can be a
cylindrical shaped lens that converts the emitted light 522 to a
line. In certain embodiments, the lens 512 is configured to create
a line with a displacement of ranges such as 1-20 degrees, 5-15
degrees, and 8-12 degrees.
[0058] After passing through the lens 512, the emitted light 522
passes through an aperture 524 in the static reflecting apparatus
516 towards the rotatable reflecting apparatus 514. An example
reflecting apparatus is shown in FIG. 2 and described in more
detail above with respect to the measurement device 100 of FIG. 1.
The rotatable reflecting apparatus 514 is coupled to a device
(e.g., motor 124 of FIG. 1) that rotates the rotatable reflecting
apparatus 514. The rotatable reflecting apparatus 514 comprises a
plurality of facets/faces 526. Each facet 526 comprises a
reflective surface such as a mirror.
[0059] When the scan line created by the lens 512 is reflected by
the rotatable reflective apparatus 514, a resulting light pattern
is created. The light pattern has a vertical component and a
horizontal component that makeup the field of view of the
measurement device 500. The horizontal component (or displacement)
portion of the light pattern is created by the rotatable reflective
apparatus 514, and the vertical component is created by the lens
512. When the lens 512 creates a line with a 10-degree displacement
and the rotatable reflecting apparatus 514 includes six facets, the
vertical component of the light pattern is 10 degrees and the
horizontal component is 60 degrees. As such, the measurement device
500 can be said to have a 10-degree by 60-degree field of view.
[0060] The emitted light 522 is transmitted out of the housing 502
(e.g., through the translucent cover 506) of the measurement device
500 towards objects. A portion of the emitted light reflects off
the objects and returns through the cover 506. This light, referred
to as backscattered light, is represented in FIG. 8 by multiple
arrows 528 (not all of which are associated with a reference number
in FIG. 8). In certain embodiments, the backscattered light 528 is
reflected by the same facet 526 on the rotatable reflecting
apparatus 514 that the emitted light 522 reflected against before
being transmitted out of the housing 502.
[0061] After being reflected by the rotatable reflecting apparatus
514, the backscattered light 528 is directed towards the static
reflecting apparatus 516. In certain embodiments, the static
reflecting apparatus 516 is a mirror (e.g., a folding mirror) that
reflects the backscattered light 528 towards the focusing apparatus
518.
[0062] The focusing apparatus 518 is an optical element that
focuses the backscattered light 528 towards the detector 520. The
focusing apparatus 518 is shown in FIG. 8 as a lens with its focal
point positioned at the detector 520. The particular shape, size,
position, and orientation of the focusing apparatus 518 in the
measurement device 500 can depend on, among other things, the
position of the detector(s) 520, where the path(s) at which
backscattered light 528 is directed within the housing 502, and
space constraints of the measurement device 500.
[0063] The focusing apparatus 518 focuses backscattered light to
the detector 520, such as one or more photodetectors/sensors
arranged in one or more arrays. In response to receiving the
focused backscattered light, the detector 520 generates one or more
sensing signals, which are ultimately used to detect the distance
and/or shapes of objects that reflect the emitted light back
towards the measurement device 500 and ultimately to the detector
520.
[0064] FIG. 9 shows a measurement device 600 including a housing
602 with a base member 604 and a transparent cover 606 that can be
coupled together to surround an internal cavity 608 in which
various components of the measurement device 600 are positioned.
For simplicity, the housing 602 in FIG. 9 is shown with only the
base member 604 and the cover 606, but the housing 602 can comprise
any number of components that can be assembled together to create
the internal cavity 608 and secure components of the measurement
device 600.
[0065] The measurement device 600 includes a light source 610, a
rotatable mirror 612, a first lens 614, a second lens 616, a
rotatable reflecting apparatus 618, a static reflecting apparatus
620, a focusing apparatus 622, and a detector 624. The light source
610 can be a laser or a light-emitting diode configured to emit
coherent light. In certain embodiments, the light source 610 emits
light within the infrared spectrum while in other embodiments the
light source 610 emits light within the visible spectrum. In
certain embodiments, the light source 610 is configured to emit
light in pulses.
[0066] The emitted light is first directed towards the rotatable
mirror 612, which reflects the light towards the first lens 614,
the second lens 616, and the rotatable reflecting apparatus 618.
The emitted light and its direction are represented in FIG. 9 by
arrows 626. The rotatable mirror 612 can be a silicone-based MEMS
mirror. The rotatable mirror 612 can rotate around an axis such
that the emitted light is scanned back and forth along a line. Put
another way, the rotatable mirror 612 can be used to steer the
emitted light 624 along a line. As shown in FIG. 9, the rotatable
mirror 612 is angled at a nominal angle of 45 degrees with respect
to a direction of the emitted light 626 from the light source 610
such that the emitted light 626 is reflected at a nominal angle of
90 degrees. In certain embodiments, the rotatable mirror 612 is
configured to rotate around the axis within ranges such as 1-20
degrees, 5-15 degrees, and 8-12 degrees.
[0067] After reflecting off the rotatable mirror 612, the scanning
line of emitted light 626 is directed to the first lens 614. The
first lens 614 magnifies the emitted light, which is then directed
towards the second lens 616. The second lens 616 collimates the
magnified light, which is then directed towards the rotatable
reflecting apparatus 618. In certain embodiments, as shown in FIG.
9, the focal point of the second lens 616 is at or near an aperture
630 of the static reflecting apparatus 620. Such an arrangement
allows use of a larger-sized rotatable mirror and reduces the need
for a larger-sized aperture in the focusing apparatus 622, and
therefore, increase the amount of light focused to the detector
624.
[0068] An example reflecting apparatus is shown in FIG. 2 and
described in more detail above with respect to the measurement
device 100 of FIG. 1. The rotatable reflecting apparatus 618 is
coupled to a device (e.g., motor 124 of FIG. 1) that rotates the
rotatable reflecting apparatus 618. The rotatable reflecting
apparatus 618 comprises a plurality of facets/faces 632. Each facet
632 comprises a reflective surface such as a mirror.
[0069] When the scan line created by the rotatable mirror 612, the
first lens 614, and the second lens 616 is reflected by the
rotatable reflecting apparatus 618, a resulting light pattern is
created. The light pattern has a vertical component and a
horizontal component that makeup the field of view of the
measurement device 600. The horizontal component (or displacement)
portion of the light pattern is created by the rotatable reflecting
apparatus 618, and the vertical component is created by the
rotatable mirror 612, the first lens 614, and the second lens 616.
When the rotatable mirror 612 rotates within a 10-degree range and
rotatable reflecting apparatus 618 includes six facets, the
vertical component of the light pattern is 10 degrees and the
horizontal component is 60 degrees. As such, the measurement device
600 can be said to have a 10-degree by 60-degree field of view.
[0070] The emitted light 626 is transmitted out of the housing 602
(e.g., through the translucent cover 606) of the measurement device
600 towards objects. A portion of the emitted light reflects off
the objects and returns through the cover 606. This light, referred
to as backscattered light, is represented in FIG. 9 by multiple
arrows 634 (not all of which are associated with a reference number
in FIG. 9). In certain embodiments, the backscattered light 634 is
reflected by the same facet 632 on the rotatable reflecting
apparatus 614 that the emitted light 626 reflected against before
being transmitted out of the housing 602.
[0071] After being reflected by the rotatable reflecting apparatus
614, the backscattered light 634 is directed towards the static
reflecting apparatus 620. In certain embodiments, the static
reflecting apparatus 620 is a mirror (e.g., a folding mirror) that
reflects the backscattered light 634 towards the focusing apparatus
622.
[0072] The focusing apparatus 622 is an optical element that
focuses the backscattered light 634 towards the detector 624. The
focusing apparatus 622 is shown in FIG. 9 as a lens with its focal
point positioned at the detector 624. The particular shape, size,
position, and orientation of the focusing apparatus 622 in the
measurement device 600 can depend on, among other things, the
position of the detector(s) 624, where the path(s) at which
backscattered light 634 is directed within the housing 602, and
space constraints of the measurement device 600.
[0073] The focusing apparatus 622 focuses backscattered light 634
to the detector 624, such as one or more photodetectors/sensors
arranged in one or more arrays. In response to receiving the
focused backscattered light, the detector 624 generates one or more
sensing signals, which are ultimately used to detect the distance
and/or shapes of objects that reflect the emitted light back
towards the measurement device 600 and ultimately to the detector
624.
[0074] In certain embodiments, the measurement devices described
above are incorporated into measurement systems such that the
systems include one or more measurement devices. For example, a
measurement system for an automobile may include multiple
measurement devices, each installed at different positions on the
automobile to generate scanning light patterns and detect
backscattered light in a particular direction of the automobile.
Each measurement device may include circuitry for processing the
detected backscattered light and generating signals indicative of
the detected backscattered light, which may be used by measurement
systems to determine information about objects in the measurement
devices' fields of view.
[0075] Various methods can be carried out in connection with the
measurement devices described above. As one example, a method for
generating a scanning light pattern using the measurements devices
described above includes rotating a reflecting apparatus having a
plurality of facets; generating, via a light source, pulsed light;
directing, via an optical element, the pulsed light along a line on
at least one of the facets; and reflecting, via the at least one of
the facets, the pulsed light to create the light pattern. The
method can further include reflecting, via the at least one of the
facets, backscattered light; and focusing, via a focusing
apparatus, the reflected backscattered light towards a detector.
Components of the other measurement devices described herein can be
used in various methods to generate scanning light patterns and
detect backscattered light from the scanning light patterns.
[0076] Various modifications and additions can be made to the
embodiments disclosed without departing from the scope of this
disclosure. For example, while the embodiments described above
refer to particular features, the scope of this disclosure also
includes embodiments having different combinations of features and
embodiments that do not include all of the described features.
Accordingly, the scope of the present disclosure is intended to
include all such alternatives, modifications, and variations as
falling within the scope of the claims, together with all
equivalents thereof.
* * * * *