U.S. patent application number 17/108429 was filed with the patent office on 2021-03-18 for vertical-cavity surface-emitting laser for near-field illumination of an eye.
The applicant listed for this patent is Facebook Technologies, LLC. Invention is credited to GREGORY OLEGOVIC ANDREEV, KAROL CONSTANTINE HATZILIAS, CHRISTOPHER YUAN TING LIAO, ANDREW JOHN OUDERKIRK, ROBIN SHARMA, PAUL ARMEN TCHERTCHIAN.
Application Number | 20210083455 17/108429 |
Document ID | / |
Family ID | 1000005248535 |
Filed Date | 2021-03-18 |
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United States Patent
Application |
20210083455 |
Kind Code |
A1 |
HATZILIAS; KAROL CONSTANTINE ;
et al. |
March 18, 2021 |
VERTICAL-CAVITY SURFACE-EMITTING LASER FOR NEAR-FIELD ILLUMINATION
OF AN EYE
Abstract
A vertical-cavity surface-emitting laser (VCSEL) includes a
semiconductor substrate, a first reflector, a second reflector, a
first electrical contact, a second electrical contact, and a
through-hole via. The first reflector is disposed on a first side
of the semiconductor substrate and the second reflector is disposed
between the first reflector and an emission side of the VCSEL. The
first and second electrical contacts are disposed on a second side
of the semiconductor substrate, opposite the first side, for
mounting the VCSEL to a transparent substrate. The through-hole via
electrically connects the second electrical contact to the second
reflector.
Inventors: |
HATZILIAS; KAROL CONSTANTINE;
(Kenmore, WA) ; LIAO; CHRISTOPHER YUAN TING;
(Seattle, WA) ; SHARMA; ROBIN; (Redmond, WA)
; ANDREEV; GREGORY OLEGOVIC; (Kirkland, WA) ;
TCHERTCHIAN; PAUL ARMEN; (Fremont, CA) ; OUDERKIRK;
ANDREW JOHN; (Redmond, WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Facebook Technologies, LLC |
Menlo Park |
CA |
US |
|
|
Family ID: |
1000005248535 |
Appl. No.: |
17/108429 |
Filed: |
December 1, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16517186 |
Jul 19, 2019 |
10886702 |
|
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17108429 |
|
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62858858 |
Jun 7, 2019 |
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62758459 |
Nov 9, 2018 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02B 27/0179 20130101;
H01S 5/18344 20130101; H01S 5/18361 20130101; H01S 5/0206 20130101;
H01S 5/423 20130101; G06F 3/013 20130101; G02B 2027/0187 20130101;
G02B 27/0172 20130101; G02B 2027/0178 20130101; H01S 5/18394
20130101; H01S 5/0425 20130101 |
International
Class: |
H01S 5/183 20060101
H01S005/183; G02B 27/01 20060101 G02B027/01; H01S 5/042 20060101
H01S005/042; G06F 3/01 20060101 G06F003/01; H01S 5/42 20060101
H01S005/42 |
Claims
1. A vertical-cavity surface-emitting laser (VCSEL), comprising: a
semiconductor substrate; a first reflector disposed on a first side
of the semiconductor substrate; a second reflector disposed between
the first reflector and an emission side of the VCSEL for emitting
a diverging infrared beam; a first electrical contact disposed on a
second side of the semiconductor substrate, opposite the first
side, for mounting the VCSEL to a transparent substrate, wherein
the first electrical contact is electrically coupled to the first
reflector; a second electrical contact disposed on the second side
of the semiconductor substrate, for mounting the VCSEL to the
transparent substrate; and a through-hole via for electrically
connecting the second electrical contact to the second
reflector.
2. The VCSEL of claim 1, further comprising an active region
disposed between the first reflector and the second reflector, and
wherein the through-hole via extends through the semiconductor
substrate and the active region.
3. The VCSEL of claim 1, further comprising an isolation layer
disposed between the semiconductor substrate and the second
electrical contact for electrically insulating the second
electrical contact from the first reflector, wherein the
through-hole via also extends through the isolation layer.
4. The VCSEL of claim 1, wherein the VCSEL has a footprint of less
than 125 microns by 125 microns.
5. The VCSEL of claim 1, wherein the VCSEL is configured to
generate infrared light for illuminating an eye at distance of less
than 25 mm from the eye.
6. The VCSEL of claim 1, wherein the semiconductor substrate is a
thinned semiconductor substrate such that the VCSEL has a total
thickness of less than 100 microns.
7. The VCSEL of claim 1, wherein the VCSEL is configured as a
single-mode emitter or a multi-mode emitter.
8. The VCSEL of claim 1, further comprising an aperture definition
layer disposed between the first reflector and the second
reflector, the aperture definition layer configured to beam shape
infrared light into the diverging infrared beam.
9. The VCSEL of claim 1, wherein the first reflector comprises a
first distributed Bragg reflector (DBR); and the second reflector
comprises a second DBR.
10. The VCSEL of claim 9, wherein the first DBR comprises an N
doped DBR; and the second DBR comprises a P doped DBR.
11. The VCSEL of claim 1, further comprising a wafer level optic
disposed on the emission side of the VCSEL to direct the diverging
infrared beam to illuminate an eye of a user.
12. The VCSEL of claim 11, wherein the wafer level optic is formed
from a high index Gallium arsenide (GaAs).
13. The VCSEL of claim 1, further comprising a polarization layer
disposed on the second reflector.
14. A near-eye optical element, comprising: a transparent
substrate; and an array of vertical-cavity surface-emitting lasers
(VCSELs) disposed on the transparent substrate within a field of
view of a user of the near-eye optical element, wherein at least
one VCSEL of the array comprises: a semiconductor substrate; a
first reflector disposed on a first side of the semiconductor
substrate; a mesa region disposed on the first reflector to
generate a diverging infrared beam, wherein the mesa region
includes a second reflector; a first electrical contact disposed on
a second side of the semiconductor substrate, opposite the first
side, for mounting the VCSEL to the transparent substrate, wherein
the first electrical contact is electrically coupled to the first
reflector; a second electrical contact disposed on the second side
of the semiconductor substrate, for mounting the VCSEL to the
transparent substrate; and a through-hole via for electrically
connecting the second electrical contact to the second reflector,
wherein the through-hole via extends through the semiconductor
substrate.
15. The near-eye optical element of claim 14, wherein the mesa
region further includes an active region disposed between the first
reflector and the second reflector, and wherein the through-hole
via extends through the semiconductor substrate and the active
region.
16. The near-eye optical element of claim 14, wherein the at least
one VCSEL further comprises an isolation layer disposed between the
semiconductor substrate and the second electrical contact for
electrically insulating the second electrical contact from the
first reflector, wherein the through-hole via also extends through
the isolation layer.
17. The near-eye optical element of claim 14, wherein the at least
one VCSEL has a footprint of less than 125 microns by 125
microns.
18. A head mounted device, comprising: an eye-tracking camera
configured to capture images of an eye in response to infrared
light; and a near-eye optical element configured to illuminate the
eye with the infrared light, the near-eye optical element
comprising: a transparent substrate; and an array of
vertical-cavity surface-emitting lasers (VCSELs) disposed on the
transparent substrate, wherein at least one VCSEL of the array
comprises: a semiconductor substrate; a first reflector disposed on
a first side of the semiconductor substrate; a mesa region disposed
on the first reflector to generate a diverging infrared beam,
wherein the mesa region includes a second reflector; a first
electrical contact disposed on a second side of the semiconductor
substrate, opposite the first side, for mounting the VCSEL to the
transparent substrate, wherein the first electrical contact is
electrically coupled to the first reflector; a second electrical
contact disposed on the second side of the semiconductor substrate,
for mounting the VCSEL to the transparent substrate; and a
through-hole via for electrically connecting the second electrical
contact to the second reflector, wherein the through-hole via
extends through the semiconductor substrate.
19. The head mounted device of claim 18, wherein the at least one
VCSEL has a total thickness of less than 100 microns.
20. The head mounted device of claim 18, wherein the at least one
VCSEL has a footprint of less than 125 microns by 125 microns.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser.
No. 16/517,186, filed Jul. 19, 2019, which claims the benefit of
both U.S. Provisional Application No. 62/858,858, filed Jun. 7,
2019 and U.S. Provisional Application No. 62/758,459, filed Nov. 9,
2018. U.S. application Ser. No. 16/517,186, U.S. Provisional
Application No. 62/858,858, and U.S. Provisional Application No.
62/758,459 are expressly incorporated herein by reference in their
entirety.
BACKGROUND
[0002] A head mounted device is a wearable electronic device,
typically worn on the head of a user. Head mounted devices may
include one or more electronic components for use in a variety of
applications, such as gaming, aviation, engineering, medicine,
entertainment, activity tracking, and so on. Some head mounted
devices may perform eye-tracking which may enhance the user's
viewing experience. Eye-tracking may be aided, in some cases, by
illuminating the eye of the user. Thus, some conventional head
mounted devices may incorporate an eye-tracking system that
includes an illumination source as well as a camera for tracking
movements of the user's eye.
[0003] In some instances, a vertical-cavity surface-emitting laser
(VCSEL) may be utilized as the illumination source of the
eye-tracking system. However, conventional VCSEL structures are
typically designed for applications other than eye-tracking, such
as for fiber optic communications and laser printers. The design
requirements for these other applications often results in a VCSEL
structure that is less than optimal or less effective when
incorporated into an eye-tracking system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Non-limiting and non-exhaustive aspects of the present
disclosure are described with reference to the following figures,
wherein like reference numerals refer to like parts throughout the
various views unless otherwise specified.
[0005] FIG. 1A illustrates a head mounted display (HMD), in
accordance with aspects of the present disclosure.
[0006] FIG. 1B illustrates a footprint of a vertical-cavity
surface-emitting laser (VCSEL), in accordance with aspects of the
present disclosure.
[0007] FIG. 2 illustrates an eye-tracking system, in accordance
with aspects of the present disclosure.
[0008] FIG. 3 illustrates an example block diagram of a VCSEL
structure, in accordance with aspects of the present
disclosure.
[0009] FIG. 4 illustrates an example block diagram of a VCSEL
structure, in accordance with aspects of the present
disclosure.
[0010] FIG. 5 illustrates an example block diagram of a VCSEL
structure, in accordance with aspects of the present
disclosure.
DETAILED DESCRIPTION
[0011] Various aspects and embodiments are disclosed in the
following description and related drawings to show specific
examples relating to vertical-cavity surface-emitting laser (VCSEL)
for near-field illumination of an eye of a user of a head mounted
device. Alternate aspects and embodiments will be apparent to those
skilled in the pertinent art upon reading this disclosure and may
be constructed and practiced without departing from the scope or
spirit of the disclosure. Additionally, well-known elements will
not be described in detail or may be omitted so as to not obscure
the relevant details of the aspects and embodiments disclosed
herein.
[0012] Reference throughout this specification to "one embodiment"
or "an embodiment" means that a particular feature, structure, or
characteristic described in connection with the embodiment is
included in at least one embodiment of the present invention. Thus,
the appearances of the phrases "in one embodiment" or "in an
embodiment" in various places throughout this specification are not
necessarily all referring to the same embodiment. Furthermore, the
particular features, structures, or characteristics may be combined
in any suitable manner in one or more embodiments.
[0013] FIG. 1A illustrates an example head mounted display (HMD)
100 that includes an array of VCSELs 150 emitting infrared light in
an eyebox direction, in accordance with an embodiment of the
disclosure. HMD 100 includes frame 114 coupled to arms 111A and
111B. Lenses 121A and 121B are mounted to frame 114. Lenses 121A
and 121B may be prescription lenses matched to a particular wearer
of HMD or non-prescription lenses.
[0014] An HMD, such as HMD 100 is one type of head mounted device,
typically worn on the head of a user to provide artificial reality
content to a user. Artificial reality is a form of reality that has
been adjusted in some manner before presentation to the user, which
may include, e.g., virtual reality (VR), augmented reality (AR),
mixed reality (MR), hybrid reality, or some combination and/or
derivative thereof.
[0015] In FIG. 1A, each lens 121A/121B includes a waveguide
160A/160B to direct image light generated by a display 130A/130B to
an eyebox area for viewing by a wearer of HMD 100. Display
130A/130B may include an LCD, an organic light emitting diode
(OLED) display, micro-LED display, quantum dot display,
pico-projector, or liquid crystal on silicon (LCOS) display for
directing image light to a wearer of HMD 100.
[0016] The frame 114 and arms 111A/111B of the HMD may include
supporting hardware of HMD 100. HMD 100 may include any of
processing logic, wired and/or wireless data interface for sending
and receiving data, graphic processors, and one or more memories
for storing data and computer-executable instructions. In one
embodiment, HMD 100 may be configured to receive wired power. In
one embodiment, HMD 100 is configured to be powered by one or more
batteries. In one embodiment, HMD 100 may be configured to receive
wired data including video data via a wired communication channel.
In one embodiment, HMD 100 is configured to receive wireless data
including video data via a wireless communication channel.
[0017] Lenses 121A/121B may appear transparent to a user to
facilitate augmented reality or mixed reality where a user can view
scene light from the environment around her while also receiving
image light directed to her eye(s) by waveguide(s) 160. Lenses
121A/121B may include an optical combiner 170 for directing
reflected infrared light (emitted by VCSELs 150) to an eye-tracking
camera (e.g. camera 190). The array of VCSELs 150 may be disposed
on a transparent substrate and could also be included
advantageously in a VR headset where the transparent nature of the
optical structure allows a user to view a display in the VR
headset. In some embodiments of FIG. 1A, image light is only
directed into one eye of the wearer of HMD 100. In an embodiment,
both displays 130A and 130B are included to direct image light into
waveguides 160A and 160B, respectively.
[0018] Lens 121B includes an array of VCSELs 150 arranged in an
example 5.times.5 array. The VCSELs 150 in the array may be
unevenly spaced, in some embodiments. VCSELs 150 may be infrared
light sources directing their emitted light in an eyeward direction
to an eyebox area of a wearer of HMD 100. VCSELs 150 may emit an
infrared light having a wavelength of 850 nm or 940 nm, for
example. Very small metal traces or transparent conductive layers
(e.g. indium tin oxide) may run through lens 121B to facilitate
selective illumination of each VCSEL 150. Lens 121A may be
configured similarly to the illustrated lens 121B.
[0019] While VCSELs 150 may introduce occlusions into an optical
system included in an HMD 100, VCSELs 150 and corresponding routing
may be so small as to be unnoticeable or optically insignificant to
a wearer of an HMD. Additionally, any occlusion from VCSELs 150
will be placed so close to the eye as to be unfocusable by the
human eye and therefore assist in the VCSELs 150 being not
noticeable. In addition to a wearer of HMD 100 noticing VCSELs 150,
it may be preferable for an outside observer of HMD 100 to not
notice VCSELs 150.
[0020] FIG. 1B illustrates a footprint of a VCSEL in accordance
with embodiments of the disclosure. In some embodiments, each VCSEL
150 has a footprint where the "x" dimension is less than 125
microns and the "y" dimension is less than 125 microns. In some
embodiments, each VCSEL 150 has a footprint where the "x" dimension
is less than 75 microns and the "y" dimension is less than 75
microns. At these dimensions, the VCSELs 150 may not only be
unnoticeable to a wearer of an HMD 100, the VCSELs 150 may be
unnoticeable to an outside observer of HMD 100 at a distance that
is outside of the user's personal space (0.45 m)
[0021] FIG. 2 illustrates an eye-tracking system 200 that includes
a side view of an array of VCSELs 250A-E illuminating an eyebox
area, in accordance with an embodiment of the disclosure. The array
of VCSELs includes VCSELs 250A, 250B, 250C, 250D, and 250E, in the
illustrated embodiment. As shown in FIG. 2, the array of VCSELs
250A-250C are disposed on a transparent substrate 204 that includes
an emission side 205 and a non-emission side 207. In the
illustrated example, the emission side 205 is opposite the
non-emission side 207, where the emission side is the side from
which the VCSELs 250A-250C emit infrared light. For example, VCSEL
250C illuminates eye 202 with infrared beam 261. In some examples,
infrared beam 261 is a diverging infrared beam. VCSELs 250A, 250B,
250D, and 250E may also illuminate eye 202 with respective infrared
beams (not illustrated). Infrared light emitted by VCSEL 250C
propagates along optical path 271 and reflects off eye 202
propagating along optical path 272. The infrared light propagating
along optical path 272 travels through transparent substrate 204
and encounters optical combiner 230. Optical combiner 230 directs
the infrared light to camera 210 along optical path 273. Optical
combiner 230 may be a holographic combiner or Fresnel combiner.
Optical combiner 230 may transmit visible light while reflecting or
diffracting infrared light. Therefore, eye-tracking system 200
shows how VCSELs 250A-E may perform near-eye illumination by
illuminating eye 202 with infrared light and how camera 210 may
capture infrared images of eye 202 by capturing the infrared light.
In some aspects, each of the VCSELs 250A-E are configured to
generate infrared light for illuminating the eye 202 at distance of
less than 25 mm from the eye 202.
[0022] In some embodiments, camera 210 may be configured with a
bandpass filter that accepts a narrow-band infrared light that is
the same as the narrow-band emitted by VCSELs 250A-E while the
filter rejects other wavelengths. For example, VCSELs 250A-E may
emit narrow-band infrared light centered around 940 nm while camera
210 may include a filter that accepts infrared light around 940 nm
while rejecting other light wavelengths.
[0023] FIG. 3 illustrates an example block diagram of VCSEL
structure 300 having a semiconductor substrate 310, an N doped
Distributed Bragg Reflector (DBR) 320, and a mesa region 380 that
includes an active region 330, an aperture definition layer 340,
and a P doped DBR 360. VCSEL structure 300 may be used as VCSELs
150/250. Structure 300 may also optionally include a polarization
layer 390 and a wafer level optic 372. Polarization layer 390 may
include a circular or linear polarizer, for example. Wafer level
optic 372 may be a refractive element or a diffractive element (not
illustrated). In some examples, wafer level optic 372 may be formed
from a high index material such as Gallium arsenide (GaAs). Wafer
level optic 372 may be configured to scatter, tilt and/or focus
(e.g. converge or diverge) the infrared beam 359 that is generated
by VCSEL structure 300. In the illustrated embodiment, infrared
beam 359 is a diverging infrared beam, where wafer level optic 372
is configured to direct the diverging infrared beam 359 to
illuminate the eye of the user (e.g., eye 202 of FIG. 2). In FIG.
3, semiconductor substrate 310 has been thinned to further reduce
the size of VCSEL structure 300 to have a total thickness 388 of
less than 125 microns. In one embodiment, the VCSEL structure 300
has a total thickness 388 of less than 100 microns. In conventional
applications, a conventionally-sized VCSEL may have a sufficiently
small structure for the application. However, in an eye-tracking
application where the VCSEL is positioned in the field of view of a
user, thinning semiconductor substrate 310 using known substrate
thinning techniques may further reduce the size of VCSEL structure
300 to reduce the noticeability of the structure 300 by both
wearers of an HMD and outside observers.
[0024] In FIG. 3, an electrical contact 382 facilitates the
electrical connection with N-doped DBR 320 by way of semiconductor
substrate 310. Semiconductor substrate 310 may be gallium arsenide
(GaAs) in some embodiments. An electrical contact 381 facilitates
the electrical connection with P-doped DBR 360. In some examples,
an isolation layer 384 is disposed between the electrical contact
381 and the semiconductor substrate 310 to insulate the electrical
contact 381 from making an electrical connection with N-doped DBR
320. In the illustrated embodiment, a through hole via 386
electrically couples P-doped DBR 360 with electrical contact 381.
Through hole via 386 may include a dielectric layer surrounding a
conductive cylinder (e.g. metal) so that the dielectric layer
isolates the conductive cylinder from layers 320, 330, and 340.
[0025] In another embodiment (shown in FIG. 4), an electrical
connection between electrical contact 381 and P-doped DBR 360 may
be established by disposing a conductive trace 486 on the outside
of VCSEL structure 400 where the conductive trace 486 is isolated
from layers 310, 320, 330, and 340 by an isolation layer 484 (e.g.
dielectric). In particular, FIG. 4 illustrates an example of a
VCSEL structure 400 that includes conductive trace 486 (e.g.,
deposited metal) for electrically connecting the electrical contact
381 to the P-doped DBR 360. FIG. 4 also illustrates the isolation
layer 484 disposed between the semiconductor substrate 310 and the
electrical contact 381 for electrically insulating the electrical
contact 381 from the N-doped DBR 320. The isolation layer 484 is
shown as further being disposed between the conductive trace 486
and a side-edge 402 of layers 310, 320, and 330.
[0026] In some examples, electrical contacts 381 and 382 of FIGS. 3
and 4 are configured to be disposed (e.g., mounted) on a
transparent substrate, such as transparent substrate 204 of FIG.
2.
[0027] Conventional VCSEL structures are configured in a flip chip
arrangement where the two contacts may be on the same side as the
emission beam. Or, one contact may be disposed on the bottom of a
conventional VCSEL structure while a second top contact allows for
a wire bond to establish the second electrical connection. Notably,
in the illustrated embodiments of FIGS. 3 and 4, the two contacts
are arranged on one side of the VCSEL structure 300/400 that is
opposite of the emission side of beam 359. For example, N-doped DBR
320 is shown as being disposed on a first side 305 of the
semiconductor substrate 310, whereas both electrical contacts 381
and 382 are disposed on a second side 307 of the semiconductor
substrate 310 (e.g., second side 307 is opposite the first side
305).
[0028] In different embodiments, VCSEL 300 and/or VCSEL 400 may be
configured to generate a diverging infrared beam 359. In
conventional applications of VCSELs, a narrow beam is desirable.
For example, in telecommunication applications, a converging narrow
beam assists to increase optical efficiency of fiber optic
propagation where the VCSEL is coupled to the fiber optic. Thus, in
some conventional applications, an optical element (e.g., wafer
level lens) may be incorporated into the conventional VCSEL to
produce a narrow or converging beam. However, in eye-tracking
applications, the diverging beam may be advantageous to broadly
illuminate an eye which is in the near-field (e.g. within 50 mm of
the VCSEL). The epitaxial layer of the VCSEL structure 300/400 may
be customized to achieve a broad emission cone, for example. The
spacing of the P-doped DBR 360 with respect to the N-doped DBR 320
may be changed to manipulate the beam shape of beam 359, in some
embodiments. In one embodiment, the aperture definition layer 340
may be adjusted to narrow or expand the aperture 370 to manipulate
the beam shape of diverging infrared beam 359 to the desired
diverging beam. In addition, the illustrated examples of VCSEL
structure 300/400 are shown as including a wafer-level optic 372,
which may be configured to direct the diverging infrared beam 359
to illuminate the eye of the user. That is, even with wafer level
optic 372, the resultant light generated by the VCSEL structure
300/400 is diverging.
[0029] VCSEL structure 300/400 may be configured as a single mode
emitter or a multi-mode emitter. In one embodiment, the width 392
of mesa region 380 is approximately 20 microns to generate a
multi-mode emitter. In one embodiment, the width 392 of mesa region
380 is much narrower to generate a single mode emitter. In some
examples, the width 394 of the VCSEL 300/400 is less than 75
microns, which provides a footprint of less than 75 microns by 75
microns.
[0030] FIG. 5 illustrates an example block diagram of VCSEL
structure 500 having a semiconductor structure 504 and electrical
contacts 506 and 508. VCSEL structure 500 may be used as VCSELs
150/250. Semiconductor structure 504 may optically include one or
more of a polarization layer, a wafer level optic, a Distributed
Bragg Reflector (DBR), an aperture definition layer, a mesa region,
an active region, a via, an isolation layer, a conductive trace,
and the like. In some examples, semiconductor structure 504 is
configured to generate a diverging infrared beam 510.
[0031] As shown in FIG. 5, the VCSEL structure 500 is disposed on
the non-emission side 207 of the transparent substrate 204. In some
aspects, the transparent substrate 204 is part of a near-eye
optical element such as the lenses 121A/121B and/or the optical
combiner 170 of FIG. 1A. Thus, in some examples, the semiconductor
structure 504 is configured to generate the diverging infrared beam
510 through the transparent substrate 204 to the emission side 205
of the transparent substrate for near-field illumination of an eye
of the user. In some implementations, near-field illumination
includes the VCSEL structure 500 illuminating the eye of the user
at distance of less than 25 mm from the eye.
[0032] FIG. 5 further illustrates VCSEL structure 500 as including
electrical contacts 506/508 disposed between the semiconductor
structure 504 and the transparent substrate 204. The electrical
contacts 506/508 are disposed to electrically couple the
semiconductor structure 504 to the non-emission side 207 of the
transparent substrate 204.
[0033] In some aspects, the VCSEL structure 500 has a total
thickness 388 of less than 125 microns. In another embodiment, the
VCSEL structure 300 has a total thickness 388 of less than 100
microns. In some embodiments, the VCSEL structure 500 has a width
394 that is less than 125 microns to provide a footprint that is
less than 125 microns by 125 microns. In another embodiment, each
VCSEL structure 500 has a width 394 that is less than 75 microns to
provide a footprint that is less than 75 microns by 75 microns.
[0034] Embodiments of the invention may include or be implemented
in conjunction with an artificial reality system. Artificial
reality is a form of reality that has been adjusted in some manner
before presentation to a user, which may include, e.g., a virtual
reality (VR), an augmented reality (AR), a mixed reality (MR), a
hybrid reality, or some combination and/or derivatives thereof.
Artificial reality content may include completely generated content
or generated content combined with captured (e.g., real-world)
content. The artificial reality content may include video, audio,
haptic feedback, or some combination thereof, and any of which may
be presented in a single channel or in multiple channels (such as
stereo video that produces a three-dimensional effect to the
viewer). Additionally, in some embodiments, artificial reality may
also be associated with applications, products, accessories,
services, or some combination thereof, that are used to, e.g.,
create content in an artificial reality and/or are otherwise used
in (e.g., perform activities in) an artificial reality. The
artificial reality system that provides the artificial reality
content may be implemented on various platforms, including a
head-mounted display (HMD) connected to a host computer system, a
standalone HMD, a mobile device or computing system, or any other
hardware platform capable of providing artificial reality content
to one or more viewers.
[0035] The above description of illustrated embodiments of the
invention, including what is described in the Abstract, is not
intended to be exhaustive or to limit the invention to the precise
forms disclosed. While specific embodiments of, and examples for,
the invention are described herein for illustrative purposes,
various modifications are possible within the scope of the
invention, as those skilled in the relevant art will recognize.
[0036] These modifications can be made to the invention in light of
the above detailed description. The terms used in the following
claims should not be construed to limit the invention to the
specific embodiments disclosed in the specification. Rather, the
scope of the invention is to be determined entirely by the
following claims, which are to be construed in accordance with
established doctrines of claim interpretation.
* * * * *