# US 12,002,392 B2 · Eyewear projector brightness control > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,002,392 B2 - Document ID: US12002392B2 - Status: Granted - Kind: B2 - Application number: 18/137,324 - Filed: 2023-04-20 - Published: 2023-08-10 - Granted: 2024-06-04 - Earliest claimed: 2021-03-31 - Assignees: Snap Inc. - Applicants: Snap Inc. - Inventors: Jason Heger; Gerald Nilles - Web page: https://patentgrep.com/patent/US12002392B2 ## CPC - G09G 3/002: {to project the image of a two-dimensional display, such as an array of light emitting or modulating elements or a CRT} - G02B 27/0172: {characterised by optical features} - G09G 3/3406: {Control of illumination source (illumination devices structurally associated with liquid crystal cells G02F1/1336)} - G02B 2027/0118: {comprising devices for improving the contrast of the display / brillance control visibility} - G02B 2027/0178: {Eyeglass type (eyeglass details G02C)} - G06F 3/012: {Head tracking input arrangements} - G06F 3/013: {Eye tracking input arrangements (G06F3/015 takes precedence)} - G09G 2320/0606: Manual adjustment - G09G 2320/0626: for control of overall brightness - G09G 2354/00: Aspects of interface with display user - G09G 2360/144: the light being ambient light - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Eyewear including a projector having a variable feedback loop controlling a forward current delivered to a colored light source. The colored light source is configured to generate a colored light beam to generate a displayed image. The variable feedback loop in one example has a variable resistance to selectively generate a high brightness image when the eyewear is operated outside, or in a high ambient light setting, and to selectively generate a nominal brightness image when the eyewear is operated inside. A controller selectively controls the drive current delivered to the colored light source to control the brightness mode of the image. ## Claims ### Claim 1 A projector, comprising: a light source configured to generate a light beam; a display configured to modulate the light beam to generate an image; and a controller configured to control a brightness of the light source, wherein the controller comprises a selectively configurable feedback loop including a first resistor, a second resistor, and a switch configured to selectively establish only the first resistor in the feedback loop in a first mode, and selectively establish the first resistor and the second resistor in parallel in a second mode. ### Claim 2 (depends on 1) The projector of claim 1, wherein the feedback loop is configurable in the first mode to generate the image having a first brightness, and the feedback loop is configurable in the second mode to generate the image having a second brightness that is greater than the first brightness. ### Claim 3 (depends on 2) The projector of claim 2, wherein the feedback loop has a variable resistance. ### Claim 4 (depends on 3) The projector of claim 3, wherein the feedback loop selectively controls a drive current delivered to the light source. ### Claim 5 (depends on 1) The projector of claim 1, wherein the switch is a power field effect transistor (FET). ### Claim 6 (depends on 1) The projector of claim 1, wherein the switch is in series with the first resistor. ### Claim 7 (depends on 1) The projector of claim 1, wherein the controller is configured to be controlled by a user to selectively control the brightness of the display. ### Claim 8 (depends on 1) The projector of claim 1, wherein the controller is configured to be controlled by an ambient light detector to selectively control the brightness of the display. ### Claim 9 (depends on 1) The projector of claim 1, further comprising eyewear coupled to the display. ### Claim 10 (depends on 9) The projector of claim 9, wherein the eyewear comprises a frame and an optical member supported by the frame. ### Claim 11 A method of using a projector, comprising: a light source configured to generate a light beam; a display configured to modulate the light beam to generate an image; and a controller having a feedback loop, the method comprising: controlling a brightness of the light source by the controller, wherein the controller selectively configures the feedback loop including a first resistor, a second resistor, and a switch to establish only the first resistor in the feedback loop in a first mode, and the switch selectively establishing the first resistor and the second resistor in parallel in a second mode. ### Claim 12 (depends on 11) The method of claim 11, wherein the feedback loop is configured in the first mode to generate the image having a first brightness, and the feedback loop is configured in the second mode to generate the image having a second brightness that is greater than the first brightness. ### Claim 13 (depends on 12) The method of claim 12, wherein the feedback loop has a variable resistance. ### Claim 14 (depends on 13) The method of claim 13, wherein the feedback loop selectively controls a drive current delivered to the light source. ### Claim 15 (depends on 11) The method of claim 11, wherein the switch is a power field effect transistor (FET). ### Claim 16 (depends on 11) The method of claim 11, wherein the switch is in series with the first resistor. ### Claim 17 (depends on 11) The method of claim 11, wherein the controller is configured to be controlled by a user to selectively control the brightness of the display. ### Claim 18 (depends on 11) The method of claim 11, wherein the controller is controlled by an ambient light detector to selectively control the brightness of the display. ### Claim 19 (depends on 11) The method of claim 11, wherein the projector further comprises eyewear coupled to the display. ### Claim 20 (depends on 19) The method of claim 19, wherein the eyewear comprises a frame and an optical member supported by the frame.