# US 9,040,923 B2 · Eye tracking system and related methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,040,923 B2 - Document ID: US9040923B2 - Status: Granted - Kind: B2 - Application number: 14/018,243 - Filed: 2013-09-04 - Published: 2014-05-22 - Granted: 2015-05-26 - Earliest claimed: 2012-09-04 - Assignees: Innovega, Inc. - Applicants: Innovega Inc. - Inventors: Randall B. Sprague; Arthur Zhang - Web page: https://patentgrep.com/patent/US9040923B2 ## CPC - G06F 3/013: {Eye tracking input arrangements (G06F3/015 takes precedence)} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract A tracking system for tracking an eye including a light source projecting light toward a display surface in a sequential pattern, one or more reflectors associated with an optical device, where the one or more reflectors reflect the pulses of light from the display source, one or more photo detectors, where the photo detectors detect reflected pulses of light from the light source, and a system that measures pulse timing relative to horizontal and vertical pattern to compute a gaze angle of the eye. ## Claims ### Claim 1 A tracking system for tracking an eye, the system comprising: a light source to project light scanned sequentially in a pattern; four reflectors associated with an optical device, the four reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; and a system to measure pulse timing relative to horizontal and vertical projected light pattern. ### Claim 2 (depends on 1) The tracking system as recited in claim 1, further comprising a display, wherein the light source is projected toward a surface of the display. ### Claim 3 (depends on 1) The tracking system as recited in claim 1, wherein the tracking system computes gaze angle of the eye. ### Claim 4 (depends on 1) The tracking system as recited in claim 1, wherein the light source includes a scanned beam projector. ### Claim 5 (depends on 1) The tracking system as recited in claim 1, wherein the light sources include one or more of a laser, infrared light source, infrared laser, RGB laser, or collimated LED. ### Claim 6 (depends on 1) The tracking system as recited in claim 1, wherein the one or more photo detectors are disposed outside of a projected image area of a display. ### Claim 7 (depends on 1) The tracking system as recited in claim 1, further comprising multiple reflectors associated with the optical device. ### Claim 8 A tracking system for tracking an eye, the system comprising: a light source to project light scanned sequentially in a pattern; one or more reflectors associated with an optical device, the one or more reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; and a system to measure pulse timing relative to horizontal and vertical projected light pattern, wherein the optical device includes one or more of a contact lens, or an intraocular device. ### Claim 9 A tracking system for tracking an eye, the system comprising: a light source to protect light scanned sequentially in a pattern; one or more reflectors associated with an optical device, the one or more reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; and a system to measure pulse timing relative to horizontal and vertical projected light pattern, wherein the reflectors are integrated into a contact lens. ### Claim 10 A tracking system for tracking an eye, the system comprising: a light source to project light scanned sequentially in a pattern; one or more reflectors associated with an optical device, the one or more reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; and a system to measure pulse timing relative to horizontal and vertical projected light pattern, wherein the light sources include one or more of a laser, infrared light source, infrared laser, RGB laser, or collimated LED and the reflector is a first polarization selective reflector and a polarization of the infrared laser is set to be reflected by the first polarization selective reflector. ### Claim 11 A tracking system for tracking an eye, the system comprising: a light source to project light scanned sequentially in a pattern; one or more reflectors associated with an optical device, the one or more reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; a system to measure pulse timing relative to horizontal and vertical projected light pattern, wherein the light sources include one or more of a laser, infrared light source, infrared laser, RGB laser, or collimated LED and the reflector is a first polarization selective reflector and a polarization of the infrared laser is set to be reflected by the first polarization selective reflector; and a second polarization selective reflector is proximate to the first polarization selective reflector, wherein the second polarization selective reflector is orthogonal to the first polarization selective reflector. ### Claim 12 A tracking system for tracking an eye, system comprising: a light source to project light scanned sequentially in a pattern; one or more reflectors associated with an optical device, the one or more reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; a system to measure pulse timing relative to horizontal and vertical projected light pattern; and multiple reflectors associated with the optical device, wherein the multiple reflectors reflect multiple images overlapping on the one or more photo detectors. ### Claim 13 A tracking system for tracking an eye, the system comprising: a light source to project light scanned sequentially in a pattern; one or more reflectors associated with an optical device, the one or more reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; and a system to measure pulse timing relative to horizontal and vertical projected light pattern, wherein an intensity of the light source is adjusted to optimize light received by the one or more photo detectors. ### Claim 14 A tracking system for tracking an eye, the system comprising: a light source to project light scanned sequentially in a pattern; one or more reflectors associated with an optical device, the one or more reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; and a system to measure pulse timing relative to horizontal and vertical projected light pattern, wherein the one or more photo detectors have a gain adjustment circuit for setting light threshold for generating output pulses. ### Claim 15 A tracking system for tracking an eye, the system comprising: a light source to project light scanned sequentially in a pattern; one or more reflectors associated with an optical device, the one or more reflectors to reflect light; one or more photo detectors, the photo detectors to detect reflected light from the light source; a system to measure pulse timing relative to horizontal and vertical projected light pattern; and a display, wherein the light source is projected toward a surface of the display, and the surface of the display to direct the light toward the optical device. ### Claim 16 A method for tracking an eye, the method comprising: projecting a light source on a display; reflecting the light from the light source from the display to one or more reflectors associated with a component, the component to be mounted near a human eye; reflecting light from one or more reflectors to one or more photo detectors; and measuring timing between photo detector pulses to track movement of the human eye. ### Claim 17 (depends on 16) The method as recited in claim 16, wherein the method comprises measuring timing of photo detector pulses relative to a refresh rate of the light source. ### Claim 18 (depends on 16) The method as recited in claim 16, wherein projecting the light source includes projecting horizontal and vertical pulses. ### Claim 19 (depends on 16) The method as recited in claim 16, wherein projecting the light source includes projecting a laser, a RGB light source, or a combination thereof. ### Claim 20 (depends on 16) The method as recited in claim 16, wherein projecting the light source includes projecting an infrared light source.