# US 10,372,269 B2 · Projection display apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,372,269 B2 - Document ID: US10372269B2 - Status: Granted - Kind: B2 - Application number: 15/325,675 - Filed: 2015-06-18 - Published: 2017-06-01 - Granted: 2019-08-06 - Earliest claimed: 2014-07-29 - Assignees: Sony Corporation - Applicants: Sony Corporation - Inventors: Koji Miura - Web page: https://patentgrep.com/patent/US10372269B2 ## CPC - G06F 3/0425: {using a single imaging device like a video camera for tracking the absolute position of a single or a plurality of objects with respect to an imaged reference surface, e.g. video camera imaging a display or a projection screen, a table or a wall surface, on which a computer generated image is displayed or projected (tracking a projected light spot to determine a position on a display surface G06F3/0386)} - G03B 17/54: with projector - G06F 3/0418: {for error correction or compensation, e.g. based on parallax, calibration or alignment} - H04N 9/3111: {for displaying the colours sequentially, e.g. by using sequentially activated light sources (sequential projection in colour photography G03B33/08)} - H04N 9/3155: {for controlling the light source (light source control per se H05B35/00 – H05B47/00; control of an illumination source for displays in general G09G3/3406)} - H04N 9/3164: {using multiple light sources} - H04N 9/3179: {Video signal processing therefor} - H04N 9/3194: {including sensor feedback} - H04N 9/3197: {using light modulating optical valves} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A projection display apparatus of the disclosure includes: a light valve (21) that modulates illuminating light (L1) on the basis of image data to output the modulated light; an illuminating unit (1) including a light source, and a plurality of optical members for illumination that generate the illuminating light (L1) on the basis of light from the light source to guide the illuminating light (L1) to the light valve (21); a projection lens (24) that projects the modulated light from the light valve (21) on a projection surface (30A), and allows detection light to enter from a direction opposite to a travelling direction of the modulated light; and an imaging device (22) that is disposed at a location optically conjugated with the light valve (21), and allows the detection light to enter through the projection lens. One or more of the plurality of optical members for illumination have optical property of reducing a noise component that affects the detection light and arises inside the illuminating unit (1). ## Claims ### Claim 1 A projection display apparatus, comprising: a light valve configured to modulate illuminating light, based on image data, to generate the modulated illuminating light; an illuminating unit that includes a light source, and a plurality of optical members for illumination, wherein the plurality of optical members are configured to generate the illuminating light, based on light received by the plurality of optical members from the light source, to guide the illuminating light to the light valve; a projection lens configured to: project the modulated illuminating light received from the light valve to a projection surface, and allow detection light to enter from a first direction opposite to a second direction of the modulated illuminating light; and an imaging device configured to allow the detection light to enter through the projection lens, wherein the imaging device, at a first location, is optically conjugated with the light valve that is at a second location, and wherein at least one of the plurality of optical members has optical property that reduces a noise component which affects the detection light. ### Claim 2 (depends on 1) The projection display apparatus according to claim 1, wherein the at least one of the plurality of optical members have the optical property to reduce the noise component by one of absorption, reflection, or transmission. ### Claim 3 (depends on 1) The projection display apparatus according to claim 1, wherein each of a plurality of light sources is on a corresponding optical path of a plurality of optical paths, wherein the plurality of optical members include an optical path combination element that combines two or more of the plurality of optical paths on which respective two or more light sources of the plurality of light sources are present, and wherein the optical path combination element has the optical property to reduce the noise component. ### Claim 4 (depends on 3) The projection display apparatus according to claim 3, wherein the optical path combination element has optical property to one of reflect or transmit the noise component in a direction that is deviated from an optical path of the illuminating light. ### Claim 5 (depends on 1) The projection display apparatus according to claim 1, wherein the plurality of optical members include a mirror that bends an optical path of the illuminating light, and wherein the mirror has the optical property to reduce the noise component. ### Claim 6 (depends on 5) The projection display apparatus according to claim 5, wherein the mirror has optical property to transmit the noise component in a direction that is deviated from the optical path of the illuminating light. ### Claim 7 (depends on 1) The projection display apparatus according to claim 1, further comprising: an absorber that is in a direction that is deviated from an optical path of the illuminating light, wherein the absorber is configured to absorb the noise component, and wherein the at least one of the plurality of optical members have optical property to guide the noise component in the direction that is deviated from the optical path of the illuminating light, by one of reflection or transmission. ### Claim 8 (depends on 1) The projection display apparatus according to claim 1, wherein the noise component includes light of an invisible light band. ### Claim 9 (depends on 1) The projection display apparatus according to claim 1, wherein the noise component includes light of an infrared light band. ### Claim 10 (depends on 1) The projection display apparatus according to claim 1, wherein a wavelength band of the noise component and a wavelength band of the detection light are same. ### Claim 11 (depends on 1) The projection display apparatus according to claim 1, wherein the noise component is a component included in the light generated from the light source. ### Claim 12 (depends on 1) The projection display apparatus according to claim 1, further comprising: an image processor configured to: detect, based on a result of imaging operation by the imaging device, a position of a feature point of an object that is one of on the projection surface or in vicinity of the projection surface, wherein the position corresponds to coordinates of a projection image projected on the projection surface. ### Claim 13 (depends on 1) The projection display apparatus according to claim 1, further comprising: a light source unit configured to emit invisible light for detection of an object at a height from the projection surface, wherein the imaging device is further configured to allow the invisible light to diffuse by a hitting operation executed on the object, as the detection light, to enter through the projection lens. ### Claim 14 (depends on 13) The projection display apparatus according to claim 13, wherein the light source unit is further configured to emit infrared light as the invisible light for detection. ### Claim 15 (depends on 1) The projection display apparatus according to claim 1, further comprising: a light source unit configured to emit invisible light, to cover at least a part of a projection area on the projection surface, for detection an object from a height, wherein the projection area is projected by the projection lens, and wherein the imaging device is further configured to allow the invisible light to diffuse by a hitting operation executed on an object in vicinity of the projection area, as the detection light, to enter through the projection lens.