# US 11,307,654 B1 · Ambient light eye illumination for eye-tracking in near-eye display > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,307,654 B1 - Document ID: US11307654B1 - Status: Granted - Kind: B1 - Application number: 16/245,052 - Filed: 2019-01-10 - Granted: 2022-04-19 - Earliest claimed: 2019-01-10 - Assignees: Facebook Technologies, LLC - Applicants: Facebook Technologies, LLC - Inventors: Qi Zhang; Andrew John Ouderkirk; Robin Sharma; Brian Wheelwright; Robert Dale Cavin - Web page: https://patentgrep.com/patent/US11307654B1 ## CPC - G06F 3/013: {Eye tracking input arrangements (G06F3/015 takes precedence)} - G02B 27/0172: {characterised by optical features} - G06F 3/011: {Arrangements for interaction with the human body, e.g. for user immersion in virtual reality (blind teaching G09B21/00)} - G06V 10/141: Control of illumination - G06V 10/94: Hardware or software architectures specially adapted for image or video understanding - G06V 40/18: Eye characteristics, e.g. of the iris - G06V 40/19: Sensors therefor - H04N 23/20: for generating image signals from infrared radiation only - G02B 2027/0178: {Eyeglass type (eyeglass details G02C)} - G02B 2027/0187: {slaved to motion of at least a part of the body of the user, e.g. head, eye} - G06T 7/20: Analysis of motion (motion estimation for coding, decoding, compressing or decompressing digital video signals H04N19/43, H04N19/51) - G06T 7/70: Determining position or orientation of objects or cameras (camera calibration G06T7/80) - G06T 2207/10048: Infrared image - G06T 2207/30201: Face - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract Techniques disclosed herein relate to eye illumination for eye tracking in a near-eye display system. One example of an eye illumination system includes a substrate transparent to visible light and infrared light and configured to be placed in front of an eye of a user, and a shortwave-pass filter on a first surface of the substrate. The shortwave-pass filter includes regions configured to transmit visible light and reflect infrared light in ambient light, and a plurality of windows configured to transmit both visible light and infrared light in the ambient light. ## Claims ### Claim 1 An eye illumination system for eye tracking in a near-eye display system, the eye illumination system comprising: a substrate transparent to both visible light and infrared light and configured to be placed in front of an eye of a user of the near-eye display system; and a shortwave-pass filter coupled to a first surface of the substrate, the shortwave-pass filter comprising: regions configured to transmit a first portion of visible light and reflect a first portion of infrared light found in ambient light entering the eye illumination system; and a plurality of windows configured to transmit both a second portion of visible light and a second portion of infrared light, found in the ambient light entering the eye illumination system, to the eye of the user. ### Claim 2 (depends on 1) The eye illumination system of claim 1, wherein the shortwave-pass filter comprises a plurality of dielectric layers, a diffractive optical element, or a reflective material layer. ### Claim 3 (depends on 1) The eye illumination system of claim 1, wherein the shortwave-pass filter is configured to reflect ambient light within a wavelength range between 750 nm and 2500 nm. ### Claim 4 (depends on 1) The eye illumination system of claim 1, wherein the plurality of windows is arranged according to a two-dimensional pattern. ### Claim 5 (depends on 1) The eye illumination system of claim 1, wherein the plurality of windows is arranged on circumferences of two or more areas of the shortwave-pass filter. ### Claim 6 (depends on 5) The eye illumination system of claim 5, wherein the two or more areas include an overlapped region. ### Claim 7 (depends on 1) The eye illumination system of claim 1, wherein each window of the plurality of windows is characterized by a diameter equal to or less than 200 μm. ### Claim 8 (depends on 1) The eye illumination system of claim 1, further comprising an antireflective layer on a second surface of the substrate opposite to the first surface or on the shortwave-pass filter. ### Claim 9 (depends on 1) The eye illumination system of claim 1, further comprising a second shortwave-pass filter on a second surface of the substrate opposite to the first surface, wherein: the second shortwave-pass filter includes regions configured to transmit visible light and reflect infrared light; and the second shortwave-pass filter includes a set of windows configured to transmit both visible light and infrared light. ### Claim 10 (depends on 9) The eye illumination system of claim 9, wherein the plurality of windows of the shortwave-pass filter on the first surface of the substrate is aligned with the set of windows of the second shortwave-pass filter on the second surface of the substrate. ### Claim 11 (depends on 9) The eye illumination system of claim 9, wherein a total area of the plurality of windows of the shortwave-pass filter on the first surface of the substrate is greater than a total area of the set of windows of the second shortwave-pass filter on the second surface of the substrate. ### Claim 12 (depends on 1) The eye illumination system of claim 1, wherein the substrate includes a curved or a flat surface. ### Claim 13 (depends on 1) The eye illumination system of claim 1, wherein the substrate comprises at least one of a glass, quartz, plastic, polymer, ceramic, or crystal. ### Claim 14 (depends on 1) The eye illumination system of claim 1, further comprising: a light source configured to illuminate the eye of the user; and a control circuit configured to turn off the light source upon determining that a light intensity of the ambient light is greater than a threshold value. ### Claim 15 An eye-tracking system in a display device, the eye-tracking system comprising: an infrared camera; a substrate transparent to both visible light and infrared light and configured to be placed in front of an eye of a user of the display device; and a shortwave-pass filter coupled to a first surface of the substrate, the shortwave-pass filter comprising: regions configured to transmit a first portion of visible light and reflect a first portion of infrared light found in ambient light entering the eye tracking system; and a plurality of windows configured to transmit both a second portion of visible light and a second portion of infrared light, found in the ambient light entering the eye tracking system, to the eye of the user, wherein the infrared camera is configured to capture infrared light reflected by the eye of the user. ### Claim 16 (depends on 15) The eye-tracking system of claim 15, wherein the shortwave-pass filter comprises a plurality of dielectric layers, a diffractive optical element, or a reflective material layer. ### Claim 17 (depends on 15) The eye-tracking system of claim 15, wherein each window of the plurality of windows is characterized by a diameter equal to or less than 200 μm. ### Claim 18 (depends on 15) The eye-tracking system of claim 15, further comprising a second shortwave-pass filter on a second surface of the substrate opposite to the first surface, wherein: the second shortwave-pass filter on the second surface of the substrate includes regions configured to transmit visible light and reflect infrared light; the second shortwave-pass filter includes a set of windows configured to transmit both visible light and infrared light; and a total area of the plurality of windows of the shortwave-pass filter on the first surface of the substrate is greater than a total area of the set of windows of the second shortwave-pass filter on the second surface of the substrate. ### Claim 19 (depends on 15) The eye-tracking system of claim 15, further comprising an antireflective layer on a second surface of the substrate opposite to the first surface or on the shortwave-pass filter. ### Claim 20 (depends on 15) The eye-tracking system of claim 15, further comprising: a light source configured to illuminate the eye of the user; and a control circuit configured to turn off the light source upon determining that a light intensity of the ambient light is greater than a threshold value.