# US 2020/0041888 A1 · Projection apparatus that projects image using laser beams, control method of the same, and storage medium > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0041888 A1 - Document ID: US20200041888A1 - Status: Published application - Kind: A1 - Application number: 16/525,740 - Filed: 2019-07-30 - Published: 2020-02-06 - Earliest claimed: 2018-08-02 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Takuya Iwata - Web page: https://patentgrep.com/patent/US20200041888A1 ## CPC - G03B 21/2033: {LED or laser light sources} - G03B 21/142: {Adjusting of projection optics} - G03B 21/2053: {Intensity control of illuminating light (controlled by video signal processing H04N5/74 or H04N9/31)} - G03B 21/206: {Control of light source other than position or intensity} - H04N 1/00681: {Detecting the presence, position or size of a sheet or correcting its position before scanning (H04N1/047 takes precedence; mode signalling H04N1/333; skew detection or correction in image signals H04N1/3878)} - 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)} - H04N 9/3164: {using multiple light sources} - H04N 9/3194: {including sensor feedback} - H04N 2201/0438: Scanning displays; Scanning large surfaces, e.g. projection screens, writing boards - 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 apparatus comprises: a first laser beam source configured to output a visible laser beam; a second laser beam source configured to output an invisible laser beam; a scan unit configured to project an image by scanning a projection surface using the visible laser beam output from the first laser beam source and the invisible laser beam output from the second laser beam source; and a control unit configured to control a timing at which the first laser beam source outputs the visible laser beam and a timing at which the second laser beam source outputs the invisible laser beam so that, in a period corresponding to a target pixel in the image, the visible laser beam is output in a first period and the invisible laser beam is output in a second period different from the first period. ## Claims ### Claim 1 A projection apparatus comprising: a first laser beam source configured to output a visible laser beam: a second laser beam source configured to output an invisible laser beam; a scan unit configured to project an image by scanning a projection surface using the visible laser beam output from the first laser beam source and the invisible laser beam output from the second laser beam source; and a control unit configured to control a timing at which the first laser beam source outputs the visible laser beam and a timing at which the second laser beam source outputs the invisible laser beam so that, in a period corresponding to a target pixel in the image, the visible laser beam is output in a first period and the invisible laser beam is output in a second period different from the first period. ### Claim 2 (depends on 1) The projection apparatus according to claim 1, further comprising: a detection unit configured to detect a reflected beam of the invisible laser beam; and a distance measurement unit configured to obtain a distance between the projection apparatus and an object irradiated by the invisible laser beam based on an output timing of the invisible laser beam and a detection timing of the reflected beam. ### Claim 3 (depends on 1) The projection apparatus according to claim 1, wherein the scan unit projects a projection image by causing the visible laser beam to scan the projection surface two-dimensionally. ### Claim 4 (depends on 3) The projection apparatus according to claim 3, wherein in order to project each pixel in the projection image, the control unit determines, on a per-pixel basis, the first period in which the visible laser beam is output, and a period in which the visible laser beam is not output, and the control unit determines the second period so that the invisible laser beam is output in the period which has been determined on the per-pixel basis and in which the visible laser beam is not output. ### Claim 5 (depends on 1) The projection apparatus according to claim 1, wherein in projecting a projection image onto the projection surface, the scan unit modulates the visible laser beam using a liquid crystal element based on an input image. ### Claim 6 (depends on 1) The projection apparatus according to claim 1, wherein the control unit controls an output timing of the second laser beam source so that the invisible laser beam is output in harmony with predetermined frames of an input image. ### Claim 7 (depends on 1) The projection apparatus according to claim 1, further comprising a generation unit configured to generate a bright image in which pixel values of an input image have been increased, and a dark image in which the pixel values of the input image have been reduced, wherein the control unit controls output timings so that the invisible laser beam is output only during a period in which the dark image is projected, and the invisible laser beam is not output in a period in which the bright image is projected. ### Claim 8 (depends on 1) The projection apparatus according to claim 1, wherein in a case where a distance between the projection apparatus and the projection surface is determined to be equal to or shorter than a predetermined threshold, the control unit thins out the number of times the invisible laser beam is output in projecting a projection image so that the number is smaller than the number of times the visible laser beam is output in projecting the projection image. ### Claim 9 (depends on 1) The projection apparatus according to claim 1, further comprising a plurality of first laser beam sources configured to output visible laser beams having different colors from one another, wherein the control unit controls output timings of the plurality of first laser beam sources so that the plurality of first laser beam sources output the visible laser beams in the first period. ### Claim 10 A control method of a projection apparatus which includes a first laser beam source configured to output a visible laser beam, a second laser beam source configured to output an invisible laser beam, and a scan unit configured to project an image by scanning a projection surface using the visible laser beam output from the first laser beam source and the invisible laser beam output from the second laser beam source, the method comprising: controlling a timing at which the first laser beam source outputs the visible laser beam and a timing at which the second laser beam source outputs the invisible laser beam so that, in a period corresponding to a target pixel in the image, the visible laser beam is output in a first period and the invisible laser beam is output in a second period different from the first period. ### Claim 11 (depends on 10) The control method according to claim 10, further comprising: detecting a reflected beam of the invisible laser beam; and obtaining a distance between the projection apparatus and an object irradiated by the invisible laser beam based on an output timing of the invisible laser beam and a detection timing of the reflected beam. ### Claim 12 (depends on 10) The control method according to claim 10, wherein the scan unit projects a projection image by causing the visible laser beam to scan the projection surface two-dimensionally. ### Claim 13 (depends on 12) The control method according to claim 12, wherein in order to project each pixel in the projection image, in the controlling: determining, on a per-pixel basis, the first period in which the visible laser beam is output, and a period in which the visible laser beam is not output, and determining the second period so that the invisible laser beam is output in the period which has been determined on the per-pixel basis and in which the visible laser beam is not output. ### Claim 14 (depends on 10) The control method according to claim 10, wherein in projecting a projection image onto the projection surface, the scan unit modulates the visible laser beam using a liquid crystal element based on an input image. ### Claim 15 (depends on 10) The control method according to claim 10, wherein in the controlling, controlling an output timing of the second laser beam source so that the invisible laser beam is output in harmony with predetermined frames of an input image. ### Claim 16 (depends on 10) The control method according to claim 10, further comprising generating a bright image in which pixel values of an input image have been increased, and a dark image in which the pixel values of the input image have been reduced, wherein in the controlling, controlling output timings so that the invisible laser beam is output only during a period in which the dark image is projected, and the invisible laser beam is not output in a period in which the bright image is projected. ### Claim 17 (depends on 10) The control method according to claim 10, wherein in a case where a distance between the projection apparatus and the projection surface is determined to be equal to or shorter than a predetermined threshold, the controlling thins out the number of times the invisible laser beam is output in projecting a projection image so that the number is smaller than the number of times the visible laser beam is output in projecting the projection image. ### Claim 18 (depends on 10) The control method according to claim 10, wherein the projection apparatus includes a plurality of first laser beam sources configured to output visible laser beams having different colors from one another, wherein in the controlling, controlling output timings of the plurality of first laser beam sources so that the plurality of first laser beam sources output the visible laser beams in the first period. ### Claim 19 A non-transitory computer-readable storage medium storing a program for causing a computer to execute a control method of a projection apparatus which includes a first laser beam source configured to output a visible laser beam, a second laser beam source configured to output an invisible laser beam, and a scan unit configured to project an image by scanning a projection surface using the visible laser beam output from the first laser beam source and the invisible laser beam output from the second laser beam source, the method comprising: controlling a timing at which the first laser beam source outputs the visible laser beam and a timing at which the second laser beam source outputs the invisible laser beam so that, in a period corresponding to a target pixel in the image, the visible laser beam is output in a first period and the invisible laser beam is output in a second period different from the first period.