# US 11,898,726 B2 · Light irradiation device including reflection surfaces and a rotation mechanism > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,898,726 B2 - Document ID: US11898726B2 - Status: Granted - Kind: B2 - Application number: 17/909,756 - Filed: 2020-03-13 - Published: 2023-03-30 - Granted: 2024-02-13 - Earliest claimed: 2020-03-13 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Masashige Suwa; Ritsuya Oshima; Muneharu Kuwata - Web page: https://patentgrep.com/patent/US11898726B2 ## CPC - F21S 41/143: the main emission direction of the LED being parallel to the optical axis of the illuminating device - F21V 14/04: by movement of reflectors {(in vehicle head lamps F21S41/675)} - B60Q 1/076: by electrical means {including means to transmit the movements, e.g. shafts or joints} - F21S 41/153: arranged in a matrix - F21S 41/25: Projection lenses - F21S 41/321: {the reflector being a surface of revolution or a planar surface, e.g. truncated} - F21S 41/365: successively reflecting the light - F21S 41/663: by switching light sources (by switching incandescent light sources F21S41/162) - F21S 41/675: by moving reflectors - G02B 26/105: {with one or more pivoting mirrors or galvano-mirrors (G02B26/101 takes precedence)} - F21S: NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - B60Q: ARRANGEMENT OF SIGNALLING OR LIGHTING DEVICES, THE MOUNTING OR SUPPORTING THEREOF OR CIRCUITS THEREFOR, FOR VEHICLES IN GENERAL - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract A light irradiation device includes a light source, a first reflecting surface, a second reflecting surface and a rotation mechanism that rotates the first reflecting surface around a first central axis passing through a center of the first reflecting surface and rotates the second reflecting surface around a second central axis passing through a center of the second reflecting surface. The first central axis is orthogonal to a first reference surface that is 45 degrees inclined with respect to a first plane that is orthogonal to an optical axis of light incident upon the first reflecting surface, the second central axis is orthogonal to a second reference surface parallel to the first reference surface, and the first reflecting surface is inclined with respect to the first reference surface and the second reflecting surface is inclined with respect to the second reference surface. ## Claims ### Claim 1 A light irradiation device that scans illuminating light, comprising: a light source to emit light; a first reflecting surface to reflect and deflect the light emitted from the light source and forming a planar-like image; a second reflecting surface to reflect and deflect the light deflected by the first reflecting surface; and a rotation mechanism to rotate the first reflecting surface around a first central axis passing through a center of the first reflecting surface and to rotate the second reflecting surface around a second central axis passing through a center of the second reflecting surface, wherein the first central axis is orthogonal to a first reference surface as a virtual plane that is 45 degrees inclined with respect to a first plane that is orthogonal to an optical axis of the light incident upon the first reflecting surface, the second central axis is orthogonal to a second reference surface as a virtual plane parallel to the first reference surface, and the first reflecting surface is inclined with respect to the first reference surface and the second reflecting surface is inclined with respect to the second reference surface. ### Claim 2 (depends on 1) The light irradiation device according to claim 1, further comprising an image formation lens that is arranged between the light source and the first reflecting surface and emits light that forms a second image as a magnified image of a first image that is an image formed by the light emitted from the light source, wherein the first reflecting surface deflects the light emitted from the image formation lens. ### Claim 3 (depends on 2) The light irradiation device according to claim 2, wherein the image formation lens has positive power, and a magnification ratio of the second image with respect to the first image in the illuminating light is determined by the image formation lens. ### Claim 4 (depends on 2) The light irradiation device according to claim 2, wherein the image formation lens has an incidence surface upon which the light emitted from the light source is incident and an emission surface from which the light is emitted, and power of the emission surface is higher than power of the incidence surface. ### Claim 5 (depends on 1) The light irradiation device according to claim 1, wherein the rotation mechanism includes two rotary shafts and a motor to apply turning force to at least one of the two rotary shafts. ### Claim 6 (depends on 5) The light irradiation device according to claim 5, wherein one of the two rotary shafts is connected to a back side of the first reflecting surface, and the other of the two rotary shafts is connected to a back side of the second reflecting surface. ### Claim 7 (depends on 5) The light irradiation device according to claim 5, wherein at least one of the two rotary shafts is connected to a front side of the first reflecting surface or a front side of the second reflecting surface. ### Claim 8 (depends on 5) The light irradiation device according to claim 5, wherein the rotation mechanism further includes a power transmission mechanism to transmit the turning force applied from the motor to the other rotary shaft. ### Claim 9 (depends on 1) The light irradiation device according to claim 1, wherein the light source is a surface-emitting light source. ### Claim 10 (depends on 1) The light irradiation device according to claim 1, wherein a divergence angle of the light emitted from the light source is 5 degrees or more. ### Claim 11 (depends on 1) The light irradiation device according to claim 1, wherein the light source includes a plurality of surface-emitting light sources each having a planar-like light emission surface, and light beams emitted from the plurality of surface-emitting light sources are superimposed together and a planar-like image in a predetermined shape is formed. ### Claim 12 (depends on 11) The light irradiation device according to claim 11, wherein when a direction parallel to a scan direction as a direction in which an irradiation position of the illuminating light moves on a plane orthogonal to an emission direction of the illuminating light is represented as a first direction and a direction orthogonal to both of the emission direction and the first direction is represented as a second direction, the plurality of surface-emitting light sources are arranged so that light emission surfaces of the plurality of surface-emitting light sources are arranged in the second direction. ### Claim 13 (depends on 11) The light irradiation device according to claim 11, wherein when a direction parallel to a scan direction as a direction in which an irradiation position of the illuminating light moves on a plane orthogonal to an emission direction of the illuminating light is represented as a first direction and a direction orthogonal to both of the emission direction and the first direction is represented as a second direction, the plurality of surface-emitting light sources are arranged so that light emission surfaces of the plurality of surface-emitting light sources are arranged in the second direction and first direction positions of light emission surfaces adjoining each other in the second direction differ from each other. ### Claim 14 (depends on 11) The light irradiation device according to claim 11, wherein when a direction parallel to a scan direction as a direction in which an irradiation position of the illuminating light moves on a plane orthogonal to an emission direction of the illuminating light is represented as a first direction, the plurality of surface-emitting light sources are arranged so that light emission surfaces of the plurality of surface-emitting light sources are arranged in the first direction. ### Claim 15 (depends on 1) The light irradiation device according to claim 1, further comprising a light emission control circuit to execute light emission control of the light source, wherein the light emission control circuit temporally controls at least one of a light amount of the illuminating light and an irradiation pattern of the illuminating light via the light emission control of the light source. ### Claim 16 (depends on 15) The light irradiation device according to claim 15, wherein in a case where the light source includes a plurality of light emission surfaces, the light emission control circuit temporally controls at least one of the light amount and the irradiation pattern of the illuminating light by controlling the light amount of light emitted from each of the plurality of light emission surfaces independently of each other as the light emission control of the light source. ### Claim 17 (depends on 1) The light irradiation device according to claim 1, wherein an inclination angle of the first reflecting surface with respect to the first reference surface and an inclination angle of the second reflecting surface with respect to the second reference surface are equal to each other. ### Claim 18 (depends on 1) The light irradiation device according to claim 1, comprising a first optical member and a second optical member each including a bottom part and an inclined surface that is inclined with respect to the bottom part and each having a cross section in a wedge shape, wherein the first reflecting surface is formed on the inclined surface of the first optical member when the bottom part of the first optical member is regarded as the first reference surface, and the second reflecting surface is formed on the inclined surface of the second optical member when the bottom part of the second optical member is regarded as the second reference surface. ### Claim 19 (depends on 1) The light irradiation device according to claim 1, wherein an inclination angle of the first reflecting surface with respect to the first reference surface and an inclination angle of the second reflecting surface with respect to the second reference surface are less than or equal to 15 degrees. ### Claim 20 (depends on 1) The light irradiation device according to claim 1, wherein a rotation direction of the first reflecting surface and a rotation direction of the second reflecting surface are directions opposite to each other and angular speed of the rotation of the first reflecting surface and angular speed of the rotation of the second reflecting surface are equal to each other.