# US 2023/0410550 A1 · Biometric imaging device comprising color filters and method of imaging using the biometric imaging device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0410550 A1 - Document ID: US20230410550A1 - Status: Published application - Kind: A1 - Application number: 18/249,263 - Filed: 2021-11-23 - Published: 2023-12-21 - Earliest claimed: 2020-11-23 - Assignees: Fingerprint Cards Anacatum IP AB - Applicants: Fingerprint Cards Anacatum IP AB - Inventors: Arvid Hammar; Hans Martinsson - Web page: https://patentgrep.com/patent/US20230410550A1 ## CPC - G02B 5/005: {Diaphragms (for cameras G03B9/02)} - G06V 40/1318: {using electro-optical elements or layers, e.g. electroluminescent sensing} - G02B 5/204: {in which spectral selection is performed by means of a conductive grid or array, e.g. frequency selective surfaces (for use with wavelengths longer than the infrared light H01Q15/0006)} - G02B 5/28: Interference filters - G06F 3/0412: {Digitisers structurally integrated in a display} - G06V 10/143: Sensing or illuminating at different wavelengths - G06V 40/1324: {by using geometrical optics, e.g. using prisms (G06V40/1312 takes precedence)} - G06V 40/1365: {Matching; Classification} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract A display arrangement comprising an optical biometric imaging device for imaging a biometric object comprising: an image sensor comprising a plurality of photodetector pixels; a lens arrangement comprising at least one lens configured to focus light reflected by a biometric object onto the image sensor; an aperture layer arranged between the object to be imaged and the image sensor, wherein the aperture layer comprises an aperture configured to limit the amount of light reaching the image sensor; and a filter element arranged in the aperture and configured to block light within a first wavelength range, wherein an area of the filter element is smaller than an area of the aperture so that a portion of light within the first wavelength range reaching the aperture layer pass through the aperture. ## Claims ### Claim 1 A display arrangement comprising: a display panel having an array of light emitting elements; and an optical biometric imaging device arranged underneath the display panel, the optical biometric imaging device comprising: an image sensor comprising a plurality of photodetector pixels; a lens arrangement comprising at least one lens configured to focus light reflected by a biometric object onto the image sensor; an aperture layer arranged between the object to be imaged and the image sensor, wherein the aperture layer comprises an aperture configured to limit the amount of light reaching the image sensor; and a filter element arranged within the aperture and configured to block light within a first wavelength range, wherein an area of the filter element is smaller than an area of the aperture so that a portion of light within the first wavelength range reaching the aperture layer pass through the aperture; wherein at least a portion of the display corresponding to a location of the biometric imaging is controllable to operate in a first biometric imaging mode to emit light comprising wavelengths within the first wavelength range and in a second biometric imaging mode to emit light comprising wavelengths outside of the first wavelength range. ### Claim 2 (depends on 1) The display arrangement according to claim 1, wherein the filter element is configured to block light having a wavelength lower than 500 nm. ### Claim 3 (depends on 1) The display arrangement according to claim 1, wherein the display is configured to operate in the first biometric imaging mode if a light transmission rate of the display is above a predetermined threshold value. ### Claim 4 (depends on 1, 2) The display arrangement according to claim 1 or 2, wherein the display is configured to operate in the second biometric imaging mode if a light transmission rate of the display is below a predetermined threshold value. ### Claim 5 (depends on 1) The display arrangement according to claim 1, wherein the lens arrangement comprises three lenses, with a first lens being configured to be located closest to the biometric object, and wherein the aperture layer is located between the first lens and a second lens. ### Claim 6 (depends on 1) The display arrangement according to claim 1, wherein the filter element is an annular filter element arranged in the aperture. ### Claim 7 (depends on 6) The display arrangement according to claim 6, wherein the annular filter element has an outer dimeter which is the same as an inner diameter of the aperture. ### Claim 8 (depends on 6) The display arrangement according to claim 6, wherein an inner radius r0 of the annular filter element is approximately half of an inner radius r1 of the aperture, r0≈r1/2. ### Claim 9 (depends on 1) The display arrangement according to claim 1, wherein the filter element is a circular filter element arranged in the aperture. ### Claim 10 (depends on 9) The display arrangement according to claim 9, wherein the circular filter element has a radius which is approximately half of a radius of the aperture. ### Claim 11 (depends on 1) The display arrangement according to claim 1, wherein a first portion of the filter element is configured to block light within the first wavelength range and a second portion of the filter element is configured to block light within a second wavelength range different form the first wavelength range. ### Claim 12 Method of biometric imaging in a display arrangement comprising a display panel with an array of light emitting elements and an optical biometric imaging device, the optical biometric imaging device comprising: an image sensor comprising a plurality of photodetector pixels; a lens arrangement comprising at least one lens configured to focus light reflected by a biometric object onto the image sensor; an aperture layer arranged between an object to be imaged and the image sensor, wherein the aperture layer comprises an aperture configured to limit the amount of light reaching the image sensor; a filter element arranged in the aperture and configured to block light within a first wavelength range, wherein an area of the filter element is smaller than an area of the aperture so that a portion of light within the first wavelength range reaching the aperture layer pass through the aperture, wherein the method comprises: controlling least a portion of the display corresponding to a location of the biometric imaging to operate in a first biometric imaging mode to emit light comprising wavelengths within the first wavelength range or in a second biometric imaging mode to emit light comprising wavelengths outside of the first wavelength range; and by the image sensor, capturing an image of a biometric object illuminated with light emitted by the display. ### Claim 13 (depends on 12) The method according to claim 12, further comprising operating the display in the first biometric imaging mode if a light transmission rate of the display is above a predetermined threshold value. ### Claim 14 (depends on 12) The method according to claim 12, further comprising operating the display in the second biometric imaging mode if a light transmission rate of the display is below a predetermined threshold value.