# US 12,761,473 B2 · Light source unit and image display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,761,473 B2 - Document ID: US12761473B2 - Status: Granted - Kind: B2 - Application number: 18/390,954 - Filed: 2023-12-20 - Published: 2024-06-27 - Granted: 2026-10-13 - Earliest claimed: 2022-12-26 - Assignees: Nichia Corporation - Applicants: Nichia Corporation - Inventors: Wataru Kitahara; Naoki Nakamura; Takanori Aruga; Hajime Akimoto - Web page: https://patentgrep.com/patent/US12761473B2 ## CPC - G02B 27/0101: {characterised by optical features (G02B27/0172 takes precedence)} - G02B 2027/0112: {comprising device for genereting colour display} - G02B 2027/0154: {with movable elements} - G02B 2207/123: Optical louvre elements, e.g. for directional light blocking - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract A light source unit includes a display device and an imaging optical system; the display device includes a pixel column including multiple pixels arranged along a first direction; the imaging optical system includes a movable optical system and an output element; light emitted from the display device is incident on the movable optical system; the movable optical system is movable around an axis parallel to the first direction and emits light at an angle corresponding to a movement state; light is incident on the output element via the movable optical system; and the light emitted from the output element forms a first image. The imaging optical system is substantially telecentric at the first image side; and the light emitted from the display device has a substantially Lambertian light distribution. ## Claims ### Claim 1 A light source unit comprising: a display device configured to emit light having a substantially Lambertian light distribution, the display device comprising a pixel column, the pixel column comprising a plurality of pixels arranged along a first direction; and an imaging optical system comprising: a bending part comprising a movable optical system on which light emitted from the display device is incident, the movable optical system being movable around an axis parallel to the first direction, the movable optical system emitting light at an angle corresponding to a movement state, and a direction modifying part comprising an output element on which light is incident via the movable optical system, light emitted from the output element forming a first image, wherein: the imaging optical system is substantially telecentric at a first image side, the bending part is configured to bend chief rays of light emitted at different angles from the movable optical system so that the chief rays are substantially parallel to each other before and after the first image, and the direction modifying part is configured to modify a travel direction of the chief rays so that the chief rays traveling via the bending part are directed toward a formation position of the first image. ### Claim 2 (depends on 1) The light source unit according to claim 1, wherein: the movable optical system comprises a reflective mirror. ### Claim 3 (depends on 1) The light source unit according to claim 1, wherein: the movable optical system comprises a polygon mirror. ### Claim 4 (depends on 1) The light source unit according to claim 1, wherein: the movable optical system comprises a lens. ### Claim 5 (depends on 1) The light source unit according to claim 1, wherein: the display device comprises a plurality of the pixel columns arranged along a second direction crossing the first direction. ### Claim 6 (depends on 5) The light source unit according to claim 5, wherein: the plurality of the pixel columns comprise: a first pixel column comprising a plurality of first pixels, and a second pixel column comprising a plurality of second pixels, the second pixel column being located adjacent to the first pixel column in the second direction; a first pixel pitch between pixels of the plurality of first pixels is equal to a second pixel pitch between pixels of the plurality of second pixels; a length along the first direction between a center of one of the first pixels among the plurality of first pixels and a center of one of the second pixels among the plurality of second pixels is greater than 0; and the one of the second pixels is located adjacent to the one of the first pixels. ### Claim 7 (depends on 5) The light source unit according to claim 5, wherein: the plurality of the pixel columns comprise: a first pixel column comprising a plurality of first pixels configured to emit light of a first color, a second pixel column located adjacent to the first pixel column in the second direction, the second pixel column comprising a plurality of second pixels configured to emit light of a second color; and a third pixel column located adjacent to the second pixel column in the second direction, the third pixel column comprising a plurality of third pixels configured to emit light of a third color. ### Claim 8 (depends on 1) The light source unit according to claim 1, wherein: the display device is configured to emit light having a light distribution pattern in which a luminous intensity in a direction of an angle θ with respect to an optical axis of the light emitted from the display device is approximated by cosn θ times a luminous intensity at the optical axis, and n is a value greater than 0. ### Claim 9 (depends on 8) The light source unit according to claim 8, wherein: n is not more than 11. ### Claim 10 (depends on 1) The light source unit according to claim 1, wherein: each of the plurality of pixels comprises a LED element. ### Claim 11 (depends on 10) The light source unit according to claim 10, wherein: each of the plurality of LED elements is configured to emit light having a substantially Lambertian light distribution. ### Claim 12 (depends on 10) The light source unit according to claim 10, wherein: each of the plurality of pixels further comprises a wavelength conversion member located on the respective LED element. ### Claim 13 (depends on 1) The light source unit according to claim 1, further comprising: a light-shielding member located between the display device and the imaging optical system; wherein: the light-shielding member includes an aperture, a portion of light from the display device toward the imaging optical system passing through the aperture; and another portion of the light from the display device toward the imaging optical system is shielded by the light-shielding member. ### Claim 14 (depends on 1) An image display device comprising: the light source unit according to claim 1; and a reflection unit separated from the light source unit, the reflection unit configured to reflect light emitted from the imaging optical system; wherein: the first image is formed between the light source unit and the reflection unit. ### Claim 15 (depends on 14) The image display device according to claim 14, further comprising: a reflective polarizing element located at a part of an optical path between the display device and the reflection unit; wherein: chief rays of light emitted at different angles from the movable optical system are substantially parallel to each other as the chief rays pass through the first image at the part of the optical path; the reflective polarizing element is configured to transmit a first polarized light of the light emitted from the display device; and the reflective polarizing element is configured to reflect a second polarized light of the light emitted from the display device to return to the display device. ### Claim 16 (depends on 15) An automobile comprising the image display device according to claim 15 fixed to the automobile. ### Claim 17 (depends on 14) An automobile comprising the image display device according to claim 14 fixed to the automobile. ### Claim 18 An image display device comprising: a light source unit comprising: a display device configured to emit light having a substantially Lambertian light distribution, the display device comprising a pixel column, the pixel column comprising a plurality of pixels arranged along a first direction, and an imaging optical system comprising: a movable optical system on which light emitted from the display device is incident, the movable optical system being movable around an axis parallel to the first direction, the movable optical system emitting light at an angle corresponding to a movement state, and a first mirror on which light is incident via the movable optical system; a reflection unit separated from the light source unit and comprising a second mirror configured to reflect light emitted from the imaging optical system; and a windshield on which light is incident via the second mirror; wherein: the first mirror is configured to output light that forms a first image in an open space between the first mirror and the second mirror; and the light emitted from the first mirror is substantially telecentric in an entirety of the open space between the first mirror and the second mirror. ### Claim 19 (depends on 18) The image display device according to claim 18, further comprising: a reflective polarizing element located at a part of an optical path between the display device and the reflection unit; wherein: chief rays of light emitted at different angles from the movable optical system are substantially parallel to each other as the chief rays pass through the first image at the part of the optical path; the reflective polarizing element is configured to transmit a first polarized light of the light emitted from the display device; and the reflective polarizing element is configured to reflect a second polarized light of the light emitted from the display device to return to the display device. ### Claim 20 (depends on 18) An automobile comprising the image display device according to claim 18 fixed to the automobile.