Waymo LLC v. Uber Technologies, Inc. et al

Filing 1

COMPLAINT for Violation of Defense of Trade Secret Act; Demand for Jury Trial against Otto Trucking LLC, Ottomotto LLC, Uber Technologies, Inc. (Filing Fee $ 400.00, receipt number 0971-11180330.). Filed by Waymo LLC. (Attachments: #1 Exhibit A, #2 Exhibit B, #3 Exhibit C, #4 Civil Cover Sheet)(Verhoeven, Charles) (Filed on 2/23/2017) Modified on 2/28/2017 (gbaS, COURT STAFF).

Case 3:17-cv-00939 Document 1-3 Filed 02/23/17 Page 1 of 14

EXHIBIT C

Case 3:17-cv-00939 Document 1-3 Filed 02/23/17 Page 2 of 14
US009086273B1

(12) United States Patent
Gruver et al.

(10) Patent No.:

US 9,086,273 B1

(45) Date of Patent:

(54) MICROROD COMPRESSION OF LASER

º}. º

7,701,558 B2

(71) Applicant: Google Inc., Mountain View, CA (US)
-

e

-

(72) Inventors: Daniel Gruver, San Francisco, CA

(US); Pierre-Yves Droz. Mountain
View, CA (US); Gaetan Pennecot, San

; i.

4/2010 Walsh et al.

52- . ~ *
7,255,275 B2
7,688,348 B2

BEAM IN COMBINATION WITH TRANSMIT
LENS

Jul. 21, 2015

7,710,545 B2

7,969,558 B2

2005/0237519 A1 *

egnan
8/2007 Gurevich et al.
3/2010 Lubard et al.

5/2010 Cramblitt et al.

6/2011 Hall

10/2005 Bondurant et al. ........ 356/241.1

2007/02684.74 A1 :}; 1 1/2007 Omura et al. ------------------- 355/67

2008/0100820 A1* 5/2008 Sesko .........
. . 356/4.01
2009/0059183 A1* 3/2009 Tejima ............................ 353/69

Francisco, CA (US); Zachary Morriss,

2009/01472.39 A1

San Francisco,s CA (US);s Dorel Ionut

!º. A1 3: Ha
2011/0216304 A
9/2011 ºsal ºr 356/338

Iordache, Walnut Creek, CA (US)

(73) Assignee: Google Inc., Mountain View, CA (US)

(*) Notice:

Subj ect to any º the º:
º º: e 20. adjusted under
-- - *--> -

y

ays.

2011/0255070 A1* 10/2011 Phillips et al. ............... 356/4.01
2013/0114077 A1*

5/2013 Zhang ........................... 356/328

OTHER PUBLICATIONS

OSRAM Opto Semiconductors GmbH, Datasheet for SPL DL90 3
Nanostack Pulsed Laser Diode, Mar. 24, 2009.
* cited by examiner

(21) Appl. No.: 13/790,251
(22) Filed:

6/2009 Zhu et al.

y

Primary Examiner – Isam Alsomiri
Assistant Examiner – Samantha KAbraham

Mar. 8, 2013

(51) Int. Cl

(74) Attorney, Agent, or Firm — McDonnell Boehnen

Goic 30s
G0IC 3/02

(52) U.S. Cl

(2006.01)
(

2006.01

)

Hulbert & Berghoff LLP
(57)

ABSTRACT

Crºº. Goic 3/02 (2013.01)

A LIDAR device may transmit light pulses originating from

CPC

G01S 17/10: G01S 7/497: G01S 17/89:

pulses that are detected by one or more detectors. The LIDAR

Gois 7487. Goid 308

device may include a lens that both (i) collimates the light

(58) Field of Classification Search
- --- - -- --

USPC ......... 356,301,401,407, soilhistory.
sojo,62s
S
lication file f
let
h

one or more light sources and may receive reflected light

º the one or º lightsourcesto º ºeV1Ce
light
Or TrainSIII.1SS1011 1DIO all enviro?lineIII OT IIle

ee application IIIe Ior complete searcn n1story

and (ii) focuses the reflected light onto the one or more detec

References Cited

tors. Each light source may include a respective laser diode
and cylindrical lens. The laser diode may emit an uncolli
mated laserbeam that diverges more in a first direction than in
a second direction. The cylindrical lens may pre-collimate the
uncollimated laser beam in the first direction to provide a
partially collimated laser that diverges more in the second

(56)

|U.S. PATENT DOCUMENTS

3,790,277 A
4,700,301 A

2/1974 Hogan
10/1987 Dyke

4,709,195 A
4,801.201 A
5,202,742 A

11/1987 Hellekson et al.
1/1989 Eichweber
4/1993 Frank et al.

6,108,094 A *

8/2000 Tani et al. ..................... 356/417

direction than in the first direction.

20 Claims, 6 Drawing Sheets

100

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U.S. Patent

Jul. 21, 2015

Sheet 1 of 6

US 9,086,273 B1

VI.6?un 1-I

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U.S. Patent

US 9,086,273 B1

Case 3:17-cv-00939 Document 1-3 Filed 02/23/17 Page 5 of 14

U.S. Patent

Jul. 21, 2015

Sheet 3 of 6

US 9,086,273 B1

210

2–

206

FIG. 2A

} 208

212

<– 200

FIG. 2C

210

<!— 200

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U.S. Patent

Jul. 21, 2015

Sheet 5 of 6

400

Figure 4

US 9,086,273 B1

Case 3:17-cv-00939 Document 1-3 Filed 02/23/17 Page 8 of 14

U.S. Patent

602

Jul. 21, 2015

Sheet 6 of 6

US 9,086,273 B1

Emit an uncollimated laser beam from a laser diode,
in which the uncollimated laser beam has a first

divergence in a first direction and a second divergence
in a second direction, with the first divergence being
greater than the second divergence

604

Pre-Collimate the uncollimated laser beam in the first

direction to provide a partially collimated laser beam that
has a third divergence in the first direction and a fourth
divergence in the second direction, with the third divergence
being less than the fourth divergence and fourth divergence
being substantially equal to the second divergence

606

Collimate, by a lens, the partially collimated laser beam
to provide a collimated laser beam
608
Transmit the Collimated laser beam into an environment

610

Collect object-reflected light, in which the object-reflected
light includes light from the collimated laser beam that has
reflected from one or more objects in the environment
612

Focus, by the lens, the object-reflected light through a
focusing path onto a detector

Figure 6

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US 9,086,273 B1
1

2
and the fourth divergence is substantially equal to the second
divergence. The at least one detector is configured to detect
light having wavelengths in the narrow wavelength range.
The objective lens is configured to (i) collimate the partially
collimated laser beam to provide a collimated laser beam for

MICROROD COMPRESSION OF LASER
BEAM IN COMBINATION WITH TRANSMIT
LENS
BACKGROUND

transmission into an environment of the LIDAR device and

Unless otherwise indicated herein, the materials described

in this section are not prior art to the claims in this application
and are not admitted to be prior art by inclusion in this section.
Vehicles can be configured to operate in an autonomous
mode in which the vehicle navigates through an environment
with little or no input from a driver. Such autonomous
vehicles can include one or more sensors that are configured

10

to detect information about the environment in which the

vehicle operates. The vehicle and its associated computer
implemented controller use the detected information to navi
gate through the environment. For example, if the sensor(s)
detect that the vehicle is approaching an obstacle, as deter
mined by the computer-implemented controller, the control
ler adjusts the vehicle’s directional controls to cause the
vehicle to navigate around the obstacle.
One such sensor is a light detection and ranging (LIDAR)
device. A LIDAR actively estimates distances to environmen
tal features while scanning through a scene to assembly a
cloud of point positions indicative of the three-dimensional
shape of the environmental scene. Individual points are mea
sured by generating a laser pulse and detecting a returning
pulse, if any, reflected from an environmental object, and
determining the distance to the reflective object according to
the time delay between the emitted pulse and the reception of
the reflected pulse. The laser, or set of lasers, can be rapidly
and repeatedly scanned across a scene to provide continuous
real-time information on distances to reflective objects in the
scene. Combining the measured distances and the orientation
of the laser(s) while measuring each distance allows for asso
ciating a three-dimensional position with each returning
pulse. A three-dimensional map of points of reflective fea
tures is generated based on the returning pulses for the entire
scanning zone. The three-dimensional point map thereby
indicates positions of reflective objects in the scanned scene.

15

20

25

laser diode that emits an uncollimated laser beam that

35

40

45

divergence in a first direction and a second divergence in a
second direction. The first divergence is greater than the sec
ond divergence. The method further involves pre-collimating
the laser beam in the first direction to provide a partially
collimated laser beam. The partially collimated laser beam
has a third divergence in the first direction and a fourth diver
gence in the second direction. The third divergence is less
than the fourth divergence, and the fourth divergence is sub
stantially equal to the second divergence. The method also
involves collimating, by a lens, the partially collimated laser
beam to provide a collimated laser beam and transmitting the
method involves collecting object-reflected light and focus
ing, by the lens, the object-reflected light through a focusing
path onto a detector. The object-reflected light includes light
from the collimated laser beam that has reflected from one or

50

mated laser beam.
55

device that includes at least one laser diode, at least one

cylindrical lens, at least one detector, and an objective lens.
The at least one laser diode is configured to emit an uncolli
mated laser beam that includes light in a narrow wavelength
range. The uncollimated laser beam has a first divergence in a
first direction and a second divergence in a second direction.
The first divergence is greater than the second divergence.
The at least one cylindrical lens is configured to pre-collimate
the uncollimated laser beam in the first direction to provide a
partially collimated laser beam that has a third divergence in
the first direction and a fourth divergence in the second direc
tion. The third divergence is less than the fourth divergence,

In a second aspect, example embodiments provide a
LIDAR device that includes a plurality of light sources, in
which each light source is configured to emit partially colli
mated light, a plurality of detectors, in which each detector is
associated with a respective light source in the plurality of
light sources, a lens, and a mirror. The lens is configured to (i)
collimate the partially collimated light from the light sources
to provide collimated light for transmission into an environ
ment of the LIDAR device and (ii) focus onto each detector
any object-reflected light from the detector’s associated light
source that has reflected from one or more objects in the
environment of the LIDAR device. The mirror is configured
to rotate about an axis and, while rotating, reflect the colli
mated light from the lens into the environment and reflect any
object-reflected light from the environment into the lens.
In a third aspect, example embodiments provide a method.
The method involves emitting an uncollimated laser beam

collimated laser beam into an environment. In addition, the

diverges more in a first direction than in a second direction
and a cylindrical lens that pre-collimates the uncollimated
laser beam in the first direction to provide a partially colli
In a first aspect, example embodiments provide a LIDAR

environment of the LIDAR device.

from a laser diode. The uncollimated laser beam has a first
30

SUMMARY

A LIDAR device may transmit light pulses originating
from one or more light sources and may receive reflected light
pulses that are detected by one or more detectors. The LIDAR
device may include a lens that both collimates the light from
the one or more light sources and focuses the reflected light
onto one or more detectors. Each light source may include a

(ii) focus object-reflected light onto the at least one detector.
The object-reflected light includes light from the collimated
laser beam that has reflected from one or more objects in the

60

more objects in the environment.
In a fourth aspect, exemplary embodiments provide a
LIDAR device that includes means for transmitting an uncol
limating laser beam that has a first divergence in a first direc
tion and a second divergence in a second direction, in which
the first divergence is greater than the second divergence. The
LIDAR device further includes means for pre-collimating the
uncollimated laser beam in the first direction to provide a
partially collimated laser beam that has a third divergence in
the first direction and a fourth divergence in the second direc
tion, in which he third divergence is less than the fourth
divergence and the fourth divergence is substantially equal to
the second divergence. In addition, the LIDAR device
includes means for collimating the partially collimated laser
beam, means for transmitting the partially collimated laser
beam into an environment of the LIDAR device, means for

collecting object-reflected light that includes light from the
65

collimated laser beam that has reflected from one or more

objects in the environment, and means for focusing the
object-reflected light onto a detector.

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US 9,086,273 B1
4
However, by providing partially collimated laser beams that
diverge primarily in one direction, the beam widths of the
partially collimated laser beams can be made relatively small
in comparison to the aperture of the transmit/receive lens, as

3
BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a top schematic view of a LIDAR device, in
accordance with an example embodiment.
FIG. 1B is a side schematic view of a portion of the LIDAR
device of FIG. 1A, in accordance with an example embodi

can the dimensions of the reflective element that accommo

dates the beam widths of the partially collimated laser beams.
FIGS. 1A, 1B, and 1C illustrate an example LIDAR device
100. In this example, LIDAR device 100 includes light

ment.

FIG. 1C is a front schematic view of a portion of the
LIDAR device of FIG. 1A, in accordance with an example
embodiment.

sources 102, 104, and 106 and detectors 108, 110, and 112.
10

FIG. 2A is a view of a laser diode, in accordance with an

example embodiment.

FIG. 2B is a view of the laser diode of FIG. 2A in combi

nation with a cylindrical lens, in accordance with an example
embodiment.

15

FIG. 2C is another view of the laser diode and cylindrical
lens combination of FIG. 2B, in accordance with an example
embodiment.

FIG. 3 is schematic diagram of the LIDAR device of FIG.
1A transmitting a collimated laser beam, in accordance with
an example embodiment.
FIG. 4 is a view of an aperture of a lens in the LIDAR
device of FIG. 1A, in accordance with an example embodi

20

transmitted into an environment of LIDAR device 100 via a

25

mirror 116. The light transmitted from LIDAR device 100
could be reflected by one or more objects in the environment.
The light reflected from such objects may reach mirror 116
and be reflected into lens 114. Lens 114 may then focus the
object-reflected light onto one or more of detectors 108, 110,

ment.

FIG. 5A illustrates a scenario in which LIDAR device

and 112.

scanning an environment that includes two objects, in accor
dance with an example embodiment.
FIG. 5B illustrates a point cloud for the two objects

Within LIDAR device 100, light sources 102,104, and 106
could be located in a different area than detectors 108, 110,
and 112. As shown in FIG.1B, detectors 108, 110, and 112 are

scanned in the scenario illustrated in FIG. 5A, in accordance

with an example embodiment.

30

FIG. 6 is a flow chart of a method, in accordance with an

example embodiment.
DETAILED DESCRIPTION
35

A LIDAR device may transmit light pulses originating
from one or more light sources and may receive reflected light
pulses that are detected by one or more detectors. The LIDAR
device may include a transmit/receive lens that both colli
mates the light from the one or more light sources and focuses
the reflected light onto the one or more detectors. By using a
transmit/receive lens that performs both of these functions,
instead of a transmit lens for collimating and a receive lens for
focusing, advantages with respect to size, cost, and/or com
plexity can be provided.
Each light source may include a respective laser diode and
cylindrical lens. The laser diode may emit an uncollimated
laser beam that diverges more in a first direction than in a
second direction. The cylindrical lens may pre-collimate the
uncollimated laser beam in the first direction to provide a
partially collimated laser beam, thereby reducing the diver
gence in the first direction. In some examples, the partially
collimated laser beam diverges less in the first direction than

40

45

50

in the second direction. The transmit/receive lens receives the

partially collimated laser beams from the one or more light
sources via a transmission path and collimates the partially
collimated laser beams to provide collimated laser beams that

arranged vertically in a focal plane 120 of lens 114. As shown
in FIG. 1C, light sources 102, 104, and 106 are arranged
vertically in a separately-located focal plane 122 of lens 114.
Thus, as a top view of LIDAR device 100, FIG. 1A shows
light source 102 as the top-most light source in focal plane
122 and shows detector 108 as the top-most detector in focal
plane 120.
To reach lens 114, the light emitted from light sources 102,
104, and 106 may travel through a transmission path defined
by one or more reflective elements, such as a plane mirror
124. In addition, light sources 102, 104, and 106 can be
arranged to emit light in different directions. As shown in
FIG. 1C, light sources 102, 104, and 106 emit light toward
plane mirror 124 in directions indicated by rays 132a, 134a,
and 136a, respectively. As shown in FIG. 1B, rays 132a,
134a, and 136a, are reflected by plane mirror 124, as rays
132b, 134b, and 136b, respectively. Rays 132b, 134b, and
136b then pass through lens 114 and are reflected by mirror
116. FIG. 1A shows that ray 132bis reflected by mirror 116 as
ray 132c. Rays 134b and 136b may be similarly reflected by
mirror 116 but in different vertical directions. In this regard,
the vertical arrangement of light sources 102, 104, and 106,
results in rays 132b, 134b, and 136b being incident upon
mirror 116 at different vertical angles, so that mirror 116
reflects the light from light sources 102, 104, and 106 in

55

different vertical directions.

60

Light from one or more of light sources 102,104, and 106
transmitted by LIDAR device 100 via mirror 116 can be
reflected back toward mirror 116 from one of more objects in
the environment of LIDAR device 100 as object-reflected
light. Mirror 116 can then reflect the object-reflected light

are transmitted into an environment of the LIDAR device.

The collimated light transmitted from the LIDAR device
into the environment may reflect from one or more objects in
the environment to provide object-reflected light. The trans
mit/receive lens may collect the object-reflected light and
focus the object-reflected light through a focusing path onto
the one or more detectors. The transmission path through
which the transmit/receive lens receives the light from the
light sources may include a reflective element, such as a plane
mirror or prism, that partially obstructs the focusing path.

Each of light sources 102, 104, and 106 emits light in a
wavelength range that can be detected by detectors 108, 110,
and 112. The wavelength range could, for example, be in the
ultraviolet, visible, and/or infrared portions of the electro
magnetic spectrum. In some examples, the wavelength range
is a narrow wavelength range, such as provided by lasers. In
addition, the light emitted by light sources 102,104, and 106
could be in the form of pulses.
The light that is emitted by light sources 102,104, and 106
is collimated by a lens 114. The collimated light is then

into lens 114. As shown in FIG. 1B, lens 114 can focus the

65

object-reflected light onto one or more of detectors 108, 110,
and 112, via respective focusing paths 138, 140, and 142,
depending on the angle at which lens 114 receives the object
reflected light.
The angle of the object-reflected light received by lens 114
may depend on which of light sources 102,104, and 106 was

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US 9,086,273 B1
7
slow axis. When this type of laser diode is used in light
sources 102, 104, and 106, lens 114 could be an aspherical
lens with a focal length of about 100 mm. It is to be under
stood that this specific example is illustrative only. Laser
diode 202 could have a different configuration, different aper
ture sizes, different beam divergences, and/or emit different
wavelengths.
As shown in FIGS. 2B and 2C, cylindrical lens 204 may be
positioned in front of aperture 206 with its cylinder axis 214
generally parallel to slow axis 210 and perpendicular to fast
axis 208. In this arrangement, cylindrical lens 204 can pre
collimate laser beam 212 along fast axis 208, resulting in
partially collimated laser beam 216. In some examples, this
pre-collimation may reduce the divergence along fast axis
208 to about one degree or less. Nonetheless, laser beam 216
is only partially collimated because the divergence along slow
axis 210 may be largely unchanged by cylindrical lens 204.
Thus, whereas uncollimated laser beam 212 emitted by laser
diode has a higher divergence along fast axis 208 than along
slow axis 210, partially collimated laser beam 216 provided
by cylindrical lens 204 may have a higher divergence along
slow axis 210 than along fast axis 208. Further, the diver
gences along slow axis 210 in uncollimated laser beam 212
and in partially collimated laser beam 216 may be substan
tially equal.
In one example, cylindrical lens 204 is a microrod lens with
a diameter of about 600 microns that is placed about 250
microns in front of aperture 206. The material of the microrod
lens could be, for example, fused silica or a borosilicate
crown glass, such as Schott BK7. Cylindrical lens 204 could
also be used to provide magnification along fast axis 208. For
example, if the dimensions of aperture 206 are 10 microns by
200 microns, as previously described, and cylindrical lens
204 is a microrod lens as described above, then cylindrical
lens 204 may magnify the shorter dimension (corresponding
to fast axis 208) by about 20 times. This magnification effec
tively stretches out the shorter dimension of aperture 206 to
about the same as the longer dimension. As a result, when
light from laser beam 216 is focused, for example, focused
onto a detector, the focused spot could have a substantially
square shape instead of the rectangular slit shape of aperture

8
collimated by lens 114 to provide collimated laser beams that
are transmitted from LIDAR device 100 via mirror 116. Thus,
5

10

15

collimated laser beam 350 also has a beam width in the

20

vertical plane (not shown), which could be substantially
larger than beam width 354 due to the greater divergence in
the vertical plane. To minimize obstruction of focusing path
138, plane mirror 124 could have horizontal and vertical
dimensions that are just large enough to accommodate the
horizontal and vertical beam widths of partially collimated
laser beam 350, as well as the horizontal and vertical beam

25

30

35

widths of the partially collimated laser beams emitted by light
sources 104 and 106. As a result, plane mirror 124 could have
a larger cross-section in the vertical plane than in the hori
zontal plane.
To illustrate how the dimensions of plane mirror 124 may
compare to the dimensions of lens 114 in order to minimize
the obstruction of focusing path 138, FIG. 4, shows a view
from mirror 116 of lens 114 and plane mirror 124 behind it.
For purposes of illustration, lens 114 is shown with a gener
ally rectangular aperture having a horizontal dimension 400
and a vertical dimension 402. Of course, other aperture
shapes are possible as well. In this example, plane mirror 124
has a vertical dimension 404 that is the same or similar to

vertical dimension 402 of lens 114, but plane mirror 124 has
a horizontal dimension 406 that is much smaller than the
40

horizontal dimension 400 of lens 114. By having horizontal
dimension 406 of plane mirror 124 be only a fraction of
horizontal dimension 400 of horizontal dimension 400 of lens

114, plane mirror 124 may obstruct only a fraction of the
aperture of lens 114.
FIGS. 5A and 5B illustrate an example application of a

206.

FIG. 3 illustrates a scenario in which light sources 102,
104, and 106 in LIDAR device 100 are each made up of a
respective laser diode and cylindrical lens, for example, as
shown in FIGS. 2A-2C. As shown, light source 102 emits a
partially collimated laser beam 350 that is reflected by plane
mirror 124 into lens 114. In this example, partially collimated
laser beam 350 has less divergence in the horizontal plane (the
drawing plane of FIG. 3) than in the vertical plane. Thus, the
laser diode in light source 102 may be oriented with its fast
axis in the horizontal plane and its slow axis in the vertical
plane. For purposes of illustration, partially collimated laser
beam 350 is shown in FIG. 3 with no divergence in horizontal
plane. It is to be understood, however, that some amount of
divergence is possible.
Lens 114 collimates partially collimated laser beam 350 to
provide collimated laser beam 352 that is reflected by mirror
116 into the environment of LIDAR device 100. Light from
collimated laser beam 352 may be reflected by one or more
objects in the environment of LIDAR device 100. The object
reflected light may reach mirror 116 and be reflected into lens
114. Lens 114, in turn, focuses the object-reflected light
through focusing path 138 onto detector 108. Although FIG.
3 shows a partially collimated laser beam from only light
source 102, it is to be understood that light sources 104 and
106 could also emit partially collimated laser beams that are

object-reflected light from the collimated laser beams origi
nating from one or more of light sources 102, 104, and 106
may reach mirror 116 and be reflected into lens 114, which
focuses the object-reflected light onto one or more of detec
tors 108, 110, and 112, respectively.
As shown in FIG. 3, the transmission path through which
partially collimated laser beam 350 reaches lens 114 includes
a plane mirror 124 that partially obstructs focusing path 138.
However, the obstruction created by plane mirror 124 can be
minimized by having the dimensions of plane 124 correspond
to the dimensions of partially collimated laser beam 350
incident upon it. As shown, partially collimated laser beam
350 has a beam width 354 in the horizontal plane. Partially

45

LIDAR device 500, which could have the same or similar

configuration as LIDAR device 100 shown in FIG. 1. In this
example application, LIDAR device 500 is used to scan an
environment that includes a road. Thus, LIDAR device 500
could be in a vehicle, such as an autonomous vehicle, that is
50

55

60

65

traveling on the road. The environment of LIDAR device 500
in this example includes another vehicle 502 and a road sign
504. To scan through the environment, LIDAR device 500
rotates a scanning element, which could be the same or simi
lar to mirror 116, according to motion reference arrow 506
with angular velocity w. While rotating, LIDAR device 500
regularly (e.g., periodically) emits pulsed laser beams, such
as laser beam 508. Light from the emitted laser beams is
reflected by objects in the environment, such as vehicle 502
and sign 504, and are detected by one or more detectors in
LIDAR device 500. Precisely time-stamping the receipt of the
reflected signals allows for associating each reflected signal
(if any is received at all) with the most recently emitted laser
pulse and measuring the time delay between emission of the
laser pulse and reception of the reflected light. The time delay
provides an estimate of the distance to the reflective feature
based on the speed of light in the intervening atmosphere.
Combining the distance information for each reflected signal

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US 9,086,273 B1
10
with the orientation of scanning element in LIDAR device
500 for the respective pulse emission allows for determining
a position of the reflective feature in three-dimensions.
FIG. 5B symbolically illustrates a point cloud resulting
from LIDAR device 500 scanning the environment shown in
FIG. 5A. For purposes of illustration, the scan is assumed to
be in an x-y plane that is generally horizontal (e.g., parallel to
the surface of the road). It is to be understood, however, that
the scan could include a vertical component (z-dimension) as
well. In this example, the point cloud includes spatial points
512 corresponding to reflections from vehicle 502 and spatial
points 514 corresponding to reflections from sign 504. Each
spatial point in the point cloud has a line of sight (“LOS”)
distance from LIDAR device 500 and an azimuthal angle p in
the x-y plane. In this way, the scanning by LIDAR 500 can
provide information regarding the locations of reflective
objects in its environment.
FIG. 6 is a flow chart of an example method 600 of oper
ating a LIDAR device, such as LIDAR device 100. Method
600 involves emitting an uncollimated laser beam from a laser
diode, in which the laser beam has a first divergence in a first
direction and a second divergence in a second direction, with
the first divergence being greater than the second divergence
(block 602). The laser diode could be configured as shown in
FIGS. 2A-2C with a fast axis and a slow axis. Thus, the first

direction could correspond to the fast axis and the second
direction could correspond to the slow axis.
Method 600 further involves pre-collimating the uncolli
mated laser beam in the first direction to provide a partially
collimated laser beam that has a third divergence in the first
direction and a fourth divergence in the second direction, with
the third divergence being less than the fourth divergence and
the fourth divergence being substantially equal to the second
divergence (block 604). The pre-collimation could be
achieved by transmitting the laser beam through a cylindrical

beam. The collimated laser beams could be transmitted

simultaneously or sequentially. Further, the collimated laser
beam could be transmitted in different direction. The object
reflected light that is collected could include light from any of
the transmitted collimated laser beams.

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What is claimed is:

1. A light detection and ranging (LIDAR) device, compris
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that is transmitted into the environment as a collimated laser

laser diode comprises a plurality of laser diodes, the at least
one detector comprises a plurality of detectors, and the at least
one cylindrical lens comprises a plurality of cylindrical
lenses, such that each cylindrical lens in the plurality of cylin
drical lenses is associated with a corresponding laser diode in
the plurality of laser diodes.
5. The LIDAR device of claim 4, wherein each laser diode

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limated laser beam.

Although method 600 has been described with respect to
one laser diode, it is to be understood that multiple laser
diodes could be used, each emitting a respective laser beam

objects in the environment of the LIDAR device.
2. The LIDAR device of claim 1, wherein the objective lens
receives the partially collimated laser beam via a transmission
path and focuses the object-reflected light through a focusing
path, and wherein the transmission path includes a reflective
element that partially obstructs the focusing path.
4. The LIDAR device of claim 1, wherein the at least one

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collimated laser beam that has reflected from one or more

may also focus the object-reflected light through a focusing
path onto a detector (block 612). In some examples, the lens
may receive the partially collimated laser beam via a reflec
tive element, such as a plane mirror or prism, that partially
obstructs the focusing path. However, as discussed above, the
obstruction can be minimized by having the dimensions of the
reflective element match the dimensions of the partially col

mated laser beam that has reflected from one or more

3. The LIDAR device of claim 2, wherein the reflective

objects in the environment (block 610). Collecting the object
reflected light could involve a rotating mirror, such as mirror
116, reflecting the object-reflected light from the environ
ment into the lens used to collimate the laser beam. The lens

configured to detect light having wavelengths in the
narrow wavelength range; and
an objective lens, wherein the objective lens is configured
to (i) collimate the partially collimated laser beam to
provide a collimated laser beam for transmission into an
environment of the LIDAR device and (ii) focus object
reflected light onto the at least one detector, wherein the
object-reflected light comprises light from the colli

element comprises a plane mirror.

collimated laser beam from the lens into the environment.

Method 600 also involves collecting object-reflected light,
in which the object-reflected light includes light from the

is configured to emit an uncollimated laser beam com
prising light in a narrow wavelength range, wherein the
uncollimated laser beam has a first divergence in a first
direction and a second divergence in a second direction,
and wherein the first divergence is greater than the sec
ond divergence;
at least one cylindrical lens, wherein the at least one cylin
drical lens is configured to pre-collimate the uncolli
mated laser beam in the first direction to provide a par
tially collimated laserbeam that has a third divergence in
the first direction and a fourth divergence in the second
direction, wherein the third divergence is less than the
fourth divergence and the fourth divergence is substan
tially equal to the second divergence;
at least one detector, wherein the at least one detector is

A lens, such as lens 114 shown in FIGS. 1A and 1B,

collimates the partially collimated laser beam to provide a
collimated laser beam (block 606). The lens could be an
aspherical lens or a spherical lens. The collimated laser beam
is then transmitted into an environment (block 608). Trans
mitting the collimating laser beam into the environment could
involve a rotating mirror, such as mirror 116, reflecting the

1ng:

at least one laser diode, wherein the at least one laser diode

lens, as shown in FIGS. 2B and 2C and described above.

Thus, the cylindrical lens could reduce the divergence along
the fast axis so that it becomes less than the divergence along
the slow axis, while keeping the divergence along the slow
axis substantially the same.

While various example aspects and example embodiments
have been disclosed herein, other aspects and embodiments
will be apparent to those skilled in the art. The various
example aspects and example embodiments disclosed herein
are for purposes of illustration and are not intended to be
limiting, with the true scope and spirit being indicated by the
following claims.

is configured to emit a respective uncollimated laser beam in
a respective direction, and wherein each cylindrical lens is
configured to pre-collimate the uncollimated laser beam pro
duced by its corresponding laser diode to provide a corre
sponding partially collimated laser beam that is then colli
mated by the objective lens to provide a corresponding
collimated laser beam.

6. The LIDAR device of claim 5, wherein each detector in
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the plurality of detectors is associated with a corresponding
laser diode in the plurality of laser diodes, and wherein the
objective lens is configured to focus onto each detector a

Case 3:17-cv-00939 Document 1-3 Filed 02/23/17 Page 14 of 14

US 9,086,273 B1
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respective portion of the object-reflected light that comprises
light from the detector’s corresponding laser diode.

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15. The LIDAR device of claim 14, wherein each light
source in the plurality of light sources comprises a respective
laser diode and a respective cylindrical lens.

7. The LIDAR device of claim 6, wherein each laser diode

has a rectangular aperture that has a short dimension and a
long dimension, and wherein each cylindrical lens is config
ured to magnify the short dimension of the aperture of its
corresponding laser diode such that the light from the laser
diode that is focused onto the laser diode's corresponding
detector has a substantially square shape.
8. The LIDAR device of claim 1, wherein the at least one

16. The LIDAR device of claim 14, wherein the second

mirror comprises a plurality of reflective surfaces, each
reflective surface having a different tilt with respect to the
axis.
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cylindrical lens comprises at least one microrod lens.
9. The LIDAR device of claim 1, wherein the narrow wave

length range includes wavelengths of about 905 nanometers.
10. The LIDAR device of claim 1, wherein the objective
lens is an aspherical lens.
11. The LIDAR device of claim 1, further comprising a
mirror, wherein the mirror is configured to reflect the colli
mated laser beam from the objective lens into the environ
ment and to reflect the object-reflected light from the envi
ronment into the objective lens.

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12. The LIDAR device of claim 11, wherein the mirror
rotates about a vertical axis.

13. The LIDAR device of claim 12, wherein the mirror

comprises a plurality of reflective surfaces, each reflective
surface having a different tilt with respect to the vertical axis.
14. A light detection and ranging (LIDAR) device, com
prising:
a plurality of light sources, wherein each light source is
configured to emit partially collimated light;
a plurality of detectors, wherein each detector in the plu
rality of detectors is associated with a respective light
source in the plurality of light sources;
a first mirror, wherein the first mirror is configured to
reflect the partially collimated light from the light
sources;

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wherein the uncollimated laser beam has a first diver

gence in a first direction and a second divergence in a
second direction, and wherein the first divergence is
greater than the second divergence;
pre-collimating the uncollimated laser beam in the first
direction to provide a partially collimated laser beam,
wherein the partially collimated laser beam has a third
divergence in the first direction and a fourth divergence
in the second direction, and wherein the third divergence
is less than the fourth divergence and the fourth diver
gence is substantially equal to the second divergence;
collimating, by a lens, the partially collimated laser beam
to provide a collimated laser beam;
transmitting the collimated laser beam into an environ
ment;

collecting object-reflected light, wherein the object-re
flected light comprises light from the collimated laser
beam that has reflected from one or more objects in the
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a second mirror, wherein the second mirroris configured to
rotate about an axis; and

a lens, wherein the lens is configured to (i) receive, via the
first mirror, the partially collimated light from the light
sources, (ii) collimate the partially collimated light from
the light sources to provide collimated light, wherein the
second mirror is configured to reflect the collimated
light from the lens into an environment of the LIDAR
device, and (iii) focus, via a focusing path, onto each
detector any object-reflected light from the detector’s
associated light source that has reflected from one or
more objects in the environment of the LIDAR device,
wherein the second mirror is configured to reflect the
object-reflected light from the environment into the lens,
wherein the first mirror partially obstructs the focusing
path.

17. A method comprising:
emitting an uncollimated laser beam from a laser diode,

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environment; and

focusing, by the lens, the object-reflected light through a
focusing path onto a detector, wherein the lens receives
the partially collimated laser beam via a plane mirror
that partially obstructs the focusing path.
18. The method of claim 17, wherein pre-collimating the
uncollimated laser beam in the first direction to provide a
partially collimated laser beam comprises transmitting the
uncollimated laser beam through a cylindrical lens.
19. The method of claim 17, wherein transmitting the col
limated laser beam into an environment comprises a rotating
mirror reflecting the collimated laser beam from the lens into
the environment, and wherein collecting object-reflected
light comprises the rotating mirror reflecting the object-re
flected light from the environment into the lens.
20. The method of claim 17, further comprising:
rotating an optical assembly about an axis while transmit
ting the collimated laser beam into the environment and
collecting object-reflected light, wherein the optical
assembly includes the laser diode, the lens, the detector,
and the plane mirror.