# US 2025/0148741 A1 · Dot matrix projector, facial recognition module, and electronic device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0148741 A1 - Document ID: US20250148741A1 - Status: Published application - Kind: A1 - Application number: 18/430,991 - Filed: 2024-02-02 - Published: 2025-05-08 - Earliest claimed: 2023-11-02 - Assignees: Triple Win Technology(Shenzhen) Co. Ltd. - Applicants: Triple Win Technology (Shenzhen) Co. Ltd. - Inventors: Wei-Wei Qi - Web page: https://patentgrep.com/patent/US20250148741A1 ## CPC - G06V 10/143: Sensing or illuminating at different wavelengths - G02B 27/14: operating by reflection only - G02B 27/4233: {having a diffractive element [DOE] contributing to a non-imaging application (diffusers having a diffractive element G02B5/0252; filters having a diffractive element G02B5/203; systems for controlling the direction of light having diffractive elements G02B26/0808; scanning systems having diffractive elements G02B26/106; beam shaping systems using diffractive optical elements G02B27/0944; beam splitting or combining systems operating by diffraction G02B27/1086)} - G06V 10/145: Illumination specially adapted for pattern recognition, e.g. using gratings - G06V 40/166: {using acquisition arrangements} - H04N 23/11: for generating image signals from visible and infrared light wavelengths - H04N 23/56: provided with illuminating means - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A dot matrix projector includes an infrared light source used to emit infrared light, a collimating lens, a semi-transparent and semi-reflective plate on an output side of the collimating lens, a diffractive optical element on an output path of the semi-transparent and semi-reflective plate, and an infrared light conversion film on another output path of the semi-transparent and semi-reflective plate. The collimating lens is used to receive the infrared light from the infrared light source and collimate the infrared light to be parallel infrared light. The semi-transparent and semi-reflective plate is used to divide the parallel infrared light into a first part directly transmitting the semi-transparent and a second part being reflected by the semi-transparent and semi-reflective plate. The infrared light conversion film is configured to convert infrared light into visible light. A facial recognition module and an electronic device are also provided. ## Claims ### Claim 1 A dot matrix projector comprising: an infrared light source used to emit infrared light; a collimating lens, the collimating lens used to receive the infrared light from the infrared light source and collimate the infrared light to be parallel infrared light; a semi-transparent and semi-reflective plate on an output side of the collimating lens, the semi-transparent and semi-reflective plate used to divide the parallel infrared light into a first part directly transmitting the semi-transparent and a second part being reflected by the semi-transparent and semi-reflective plate; a diffractive optical element on an output path of the semi-transparent and semi-reflective plate and configured to convert infrared light into infrared spots; and an infrared light conversion film on another output path of the semi-transparent and semi-reflective plate and configured to convert infrared light into visible light. ### Claim 2 (depends on 1) The dot matrix projector of claim 1, further comprising a total reflection plate, wherein the total reflection plate is between the collimating lens and the semi-transparent and semi-reflective plate. ### Claim 3 (depends on 2) The dot matrix projector of claim 2, wherein the total reflection plate and an optical axis direction of the parallel infrared light emitted from the collimating lens form an angle of 45 degrees; and the semi-transparent and semi-reflective plate is parallel to the total reflection plate. ### Claim 4 (depends on 1) The dot matrix projector of claim 1, further comprising a first total reflection plate and a second total reflection plate, wherein the first total reflection plate is between the collimating lens and the semi-transparent and semi-reflective plate, the second total reflection plate is on one of output paths of the semi-transparent and semi-reflective plate. ### Claim 5 (depends on 4) The dot matrix projector of claim 4, wherein the infrared light conversion film is between the semi-transparent and semi-reflective plate and the second total reflection plate. ### Claim 6 (depends on 4) The dot matrix projector of claim 4, wherein the second total reflection plate is between the semi-transparent and semi-reflective plate and the infrared light conversion film. ### Claim 7 (depends on 4) The dot matrix projector of claim 4, wherein the first total reflection plate and an optical axis direction of the parallel infrared light emitted from the collimating lens form an angle of 45 degrees; the semi-transparent and semi-reflective plate is parallel to the first total reflection plate; and the second total reflection plate is perpendicular to the semi-transparent and semi-reflective plate. ### Claim 8 (depends on 1) The dot matrix projector of claim 1, wherein the diffractive optical element is on a reflecting path of the semi-transparent and semi-reflective plate, and the infrared light conversion film is on a transmitting path of the semi-transparent and semi-reflective plate. ### Claim 9 A facial recognition module comprising: a dot matrix projector used to emit infrared light, the dot matrix projector comprising: an infrared light source used to emit infrared light; a collimating lens, the collimating lens used to receive the infrared light from the infrared light source and collimate the infrared light to be parallel infrared light; a semi-transparent and semi-reflective plate on an output side of the collimating lens, the semi-transparent and semi-reflective plate used to divide the parallel infrared light into a first part directly transmitting the semi-transparent and a second part being reflected by the semi-transparent and semi-reflective plate; a diffractive optical element on an output path of the semi-transparent and semi-reflective plate and configured to convert infrared light into infrared spots; and an infrared light conversion film on another output path of the semi-transparent and semi-reflective plate and configured to convert infrared light into visible light; and an infrared camera used to receive reflected infrared light. ### Claim 10 (depends on 9) The facial recognition module of claim 9, wherein the dot matrix projector further comprises a total reflection plate, the total reflection plate is between the collimating lens and the semi-transparent and semi-reflective plate. ### Claim 11 (depends on 10) The facial recognition module of claim 10, wherein the total reflection plate and an optical axis direction of the parallel infrared light emitted from the collimating lens form an angle of 45 degrees; and the semi-transparent and semi-reflective plate is parallel to the total reflection plate. ### Claim 12 (depends on 9) The facial recognition module of claim 9, wherein the dot matrix projector further comprises a first total reflection plate and a second total reflection plate, wherein the first total reflection plate is between the collimating lens and the semi-transparent and semi-reflective plate, the second total reflection plate is on one of output paths of the semi-transparent and semi-reflective plate. ### Claim 13 (depends on 12) The facial recognition module of claim 12, wherein the infrared light conversion film is between the semi-transparent and semi-reflective plate and the second total reflection plate. ### Claim 14 (depends on 12) The facial recognition module of claim 12, wherein the second total reflection plate is between the semi-transparent and semi-reflective plate and the infrared light conversion film. ### Claim 15 (depends on 12) The facial recognition module of claim 12, wherein the first total reflection plate and an optical axis direction of the parallel infrared light emitted from the collimating lens form an angle of 45 degrees; the semi-transparent and semi-reflective plate is parallel to the first total reflection plate; and the second total reflection plate is perpendicular to the semi-transparent and semi-reflective plate. ### Claim 16 (depends on 9) The facial recognition module of claim 9, wherein the diffractive optical element is on a reflecting path of the semi-transparent and semi-reflective plate, and the infrared light conversion film is on a transmitting path of the semi-transparent and semi-reflective plate. ### Claim 17 (depends on 9) An electronic device comprising: a housing; and facial recognition module of claim 9 in the housing.