# US 10,313,645 B1 · Variable emission period for scanned-beam display > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,313,645 B1 - Document ID: US10313645B1 - Status: Granted - Kind: B1 - Application number: 15/875,781 - Filed: 2018-01-19 - Granted: 2019-06-04 - Earliest claimed: 2018-01-19 - Assignees: Microsoft Technology Licensing, LLC - Applicants: Microsoft Technology Licensing, LLC - Inventors: Robert Thomas Held; Andrew Martin Pearson - Web page: https://patentgrep.com/patent/US10313645B1 ## CPC - H04N 9/3135: {Driving therefor} - G02B 26/105: {with one or more pivoting mirrors or galvano-mirrors (G02B26/101 takes precedence)} - G02B 27/017: {Head mounted} - G02B 27/0172: {characterised by optical features} - G02B 27/0179: {Display position adjusting means not related to the information to be displayed} - G09G 3/025: {with scanning or deflecting the beams in two directions or dimensions} - H04N 9/3129: {scanning a light beam on the display screen (scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161)} - G02B 27/01: Head-up displays - G02B 2027/0123: {comprising devices increasing the field of view} - G02B 2027/014: {comprising information/image processing systems} - 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} - G02B 2027/0198: {System for aligning or maintaining alignment of an image in a predetermined direction} - G09G 2320/0247: Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes - G09G 2320/0261: in the context of movement of objects on the screen or movement of the observer relative to the screen - G09G 2320/0633: by amplitude modulation of the brightness of the illumination source - G09G 2320/064: by time modulation of the brightness of the illumination source - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - 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) ## Abstract A scanned-beam display comprises an emitter configured to emit light of controlled variable intensity, a beam-steering optic configured to steer the light to a controlled variable beam position, and a drive circuit coupled operatively to the emitter and beam-steering optic. The drive circuit is configured to apply a signal to the beam-steering optic to move the beam position along a path of pixel positions, the path including a first pixel position at the center of the field-of-view and a second pixel position at the periphery of the field-of-view. The drive circuit is further configured to drive a series of current pulses through the emitter in synchronicity with the signal, to illuminate the first pixel position during a first interval and to equivalently illuminate the second pixel position during a second interval, the emitter being driven at a higher duty cycle during the second interval than during the first. ## Claims ### Claim 1 A scanned-beam display configured to form a display image in a field-of-view of a user, the scanned-beam display comprising: an emitter configured to emit light of a controlled variable intensity; a beam-steering optic configured to receive and steer the light to a controlled variable beam position; and coupled operatively to the emitter and to the beam-steering optic, a drive circuit configured to: apply a control signal to the beam-steering optic to move the beam position along a path of pixel positions, the path including a first pixel position at a center of the field-of-view and a second pixel position at a periphery of the field-of view, and drive a series of current pulses through the emitter in synchronicity with the control signal, to illuminate the first pixel position during a first interval and to equivalently illuminate the second pixel position during a second interval, the emitter being driven at a higher duty cycle during the second interval than during the first interval. ### Claim 2 (depends on 1) The scanned-beam display of claim 1 wherein the first interval is an interval over which the beam position intersects the first pixel position, and the second interval is an interval over which the beam position intersects the second pixel position. ### Claim 3 (depends on 1) The scanned-beam display of claim 1 wherein the series of current pulses includes an excitation of base duration within the first interval and an excitation longer than the base duration within the second interval. ### Claim 4 (depends on 3) The scanned-beam display of claim 3 wherein the excitation of base duration comprises a singular current pulse. ### Claim 5 (depends on 3) The scanned-beam display of claim 3 wherein the excitation longer than the base duration comprises a singular current pulse. ### Claim 6 (depends on 3) The scanned-beam display of claim 3 wherein the excitation longer than the base duration comprises a plurality of current pulses. ### Claim 7 (depends on 6) The scanned-beam display of claim 6 wherein a duration of at least one of the plurality of current pulses is lengthened with increasing distance from the first pixel position. ### Claim 8 (depends on 6) The scanned-beam display of claim 6 wherein a number of pulses included in the plurality of current pulses increases with increasing distance from the first pixel position. ### Claim 9 (depends on 1) The scanned-beam display of claim 1 wherein the beam-steering optic includes a mirror mechanically coupled to a transducer, and wherein the control signal is applied to the transducer. ### Claim 10 (depends on 1) The scanned-beam display of claim 1 wherein the drive circuit is further configured to vary an amplitude of the series of current pulses so as to impart predetermined brightness to the first and second pixel positions. ### Claim 11 (depends on 1) The scanned-beam display of claim 1 wherein the emitter is a laser diode. ### Claim 12 (depends on 1) The scanned-beam display of claim 1 wherein the emitter is one of a plurality of emitters configured to emit light, and wherein the beam-steering optic is configured to receive and steer the light from each of the plurality of emitters. ### Claim 13 (depends on 1) The scanned-beam display of claim 1 further comprising: a sensor providing an output responsive to a head rotation of the user; and logic configured to adjust a rendering of the display image based on the output. ### Claim 14 (depends on 1) The scanned-beam display of claim 1 further comprising: a sensor providing an output responsive to displacement of the field-of-view relative to a display frame of the scanned-beam display device; and logic coupled operatively to the sensor and configured to relate each portion of the field of view to a corresponding portion of the display frame. ### Claim 15 (depends on 1) The scanned-beam display of claim 1 wherein the scanned-beam display is arranged in a near-eye display device. ### Claim 16 A scanned-beam display configured to form a display image within a display frame, the scanned-beam display comprising: an emitter configured to emit light of a controlled variable intensity; a beam-steering optic configured to receive and steer the light to a controlled variable beam position; and coupled operatively to the emitter and to the beam-steering optic, a drive circuit configured to: apply a control signal to the beam-steering optic to move the beam position along a path of pixel positions, the path including a first pixel position at a center of the display frame and a second pixel position at a periphery of the display frame, and drive a series of current pulses through the emitter in synchronicity with the control signal, to illuminate the first pixel position during a first interval and to equivalently illuminate the second pixel position during a second interval, the emitter being driven at a higher duty cycle during the second interval than during the first interval. ### Claim 17 (depends on 16) The scanned-beam display of claim 16 wherein the first interval is an interval over which the beam position intersects the first pixel position, the second interval is an interval over which the beam position intersects the second pixel position, and wherein the series of current pulses includes an excitation of base duration within the first interval and an excitation longer than the base duration within the second interval. ### Claim 18 A scanned-beam display system configured to form a display image in a field-of-view of a user, the scanned-beam display system comprising: a sensor providing an output responsive to displacement of the field-of-view relative to a display frame of the scanned-beam display device; logic coupled operatively to the sensor and configured to relate each portion of the field of view to a corresponding portion of the display frame; an emitter configured to emit light of a controlled variable intensity; a beam-steering optic configured to receive and steer the light to a controlled variable beam position; and coupled operatively to the emitter and to the beam-steering optic, a drive circuit configured to: apply a control signal to the beam-steering optic to move the beam position along a path of pixel positions, the path including a first pixel position at a center of the field of view and a second pixel position at a periphery of the field-of view, and drive a series of current pulses through the emitter in synchronicity with the control signal, to illuminate the first pixel position during a first interval and to equivalently illuminate the second pixel position during a second interval, the emitter being driven at a higher duty cycle during the second interval than during the first interval. ### Claim 19 (depends on 18) The scanned-beam display system of claim 18 wherein the sensor includes a camera configured to image an eye of the user. ### Claim 20 (depends on 18) The scanned-beam display system of claim 18 wherein the sensor includes a remote camera.