# US 12,120,470 B2 · Projection system and calibration method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,120,470 B2 - Document ID: US12120470B2 - Status: Granted - Kind: B2 - Application number: 18/173,798 - Filed: 2023-02-24 - Published: 2024-06-06 - Granted: 2024-10-15 - Earliest claimed: 2022-12-02 - Assignees: Delta Electronics, Inc. - Applicants: Delta Electronics, Inc. - Inventors: Kai-Ming Liu - Web page: https://patentgrep.com/patent/US12120470B2 ## CPC - H04N 9/3182: {Colour adjustment, e.g. white balance, shading or gamut (white balance per se H04N9/73; control of amplitude of colour signals H04N9/68; colour control circuits for displays in general G09G5/02, G09G3/2003, G09G3/3607)} - H04N 9/31: Projection devices for colour picture display {, e.g. using electronic spatial light modulators [ESLM]} - H04N 9/3194: {including sensor feedback} - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A projection system includes a light source module, an image device, a first light sensor, a second light sensor, and a processor. The light source module has at least one solid-state light-emitting device. The processor is communicatively coupled to the light source module, the first light sensor, and the second light sensor and is configured to execute a calibration procedure. ## Claims ### Claim 1 A projection system, comprising: a light source module having at least one solid-state light-emitting device; an image device; a first light sensor; a second light sensor; and a processor communicatively coupled to the light source module, the first light sensor, and the second light sensor, and configured to execute a calibration procedure, wherein the calibration procedure comprises: driving the at least one solid-state light-emitting device to generate a plurality of output powers according to a plurality of light source control signals, to sequentially emit a plurality of white lights, and to sequentially project a plurality of full white patterns on a screen through the image device; driving the first light sensor to sequentially sense the plurality of white lights and correspondingly generate a first color information; driving the second light sensor to sequentially sense the plurality of full white patterns and correspondingly generate a second color information; obtaining a corresponding relationship between the first color information and the second color information; obtaining a target color information of the second color information according to a color space coordinate in the second color information; obtaining a target color information of the first color information according to the target color information of the second color information and the corresponding relationship; and calibrating the light source control signals corresponding to the plurality of output powers according to the target color information of the first color information. ### Claim 2 (depends on 1) The projection system of claim 1, wherein the color space coordinate in the second color information is a color space coordinate of the full white pattern generated by the at least one solid-state light-emitting device with the highest one of the plurality of output powers. ### Claim 3 (depends on 1) The projection system of claim 1, wherein the first color information comprises a plurality of color space coordinates sensed by the first light sensor when the at least one solid-state light-emitting device emits the plurality of white lights with the plurality of output powers. ### Claim 4 (depends on 1) The projection system of claim 1, wherein the second color information comprises a plurality of color space coordinates sensed by the second light sensor when the at least one solid-state light-emitting device projects the plurality of full white patterns with the plurality of output powers. ### Claim 5 (depends on 1) The projection system of claim 1, further comprising an accumulated light box disposed on paths of the plurality of white lights, wherein the accumulated light box has an entrance, the plurality of white lights enter the accumulated light box through the entrance and mix uniformly in the accumulated light box, and the first light sensor is disposed on the accumulated light box. ### Claim 6 (depends on 5) The projection system of claim 5, wherein the accumulated light box further comprises a mirror configured to allow a first part of light of each of the plurality of white lights to pass through and to divert a second part of light of each of the plurality of white lights, the first light sensor is configured to receive one of the first part of light and the second part of light, and the image device is configured to receive another of the first part of light and the second part of light. ### Claim 7 (depends on 1) The projection system of claim 1, further comprising an optical fiber, wherein the light source module and the image device are respectively disposed at two ends of the optical fiber by optical coupling. ### Claim 8 (depends on 1) The projection system of claim 1, further comprising a housing, wherein the light source module and the image device are disposed in the housing, and wherein the image device comprises a light processing module and a projector lens. ### Claim 9 (depends on 1) The projection system of claim 1, wherein the second light sensor is a charge couple device camera or a complementary metal oxide semiconductor. ### Claim 10 (depends on 1) The projection system of claim 1, further comprising: an input device communicatively coupled to the processor, wherein the input device is configured to receive a calibration input, and the processor is configured to execute the calibration procedure according to the calibration input; and a display device communicatively coupled to the processor and configured to display an execution result of the calibration procedure. ### Claim 11 A calibration method of a projection system, comprising: driving at least one solid-state light-emitting device to generate a plurality of output powers according to a plurality of light source control signals, to sequentially emit a plurality of white lights, and to sequentially project a plurality of full white patterns on a screen through an image device; driving a first light sensor to sequentially sense the plurality of white lights and correspondingly generate a first color information; driving a second light sensor to sequentially sense the plurality of full white patterns and correspondingly generate a second color information; obtaining a corresponding relationship between the first color information and the second color information; obtaining a target color information of the second color information according to a color space coordinate in the second color information; obtaining a target color information of the first color information according to the target color information of the second color information and the corresponding relationship; and calibrating the light source control signals corresponding to the plurality of output powers according to the target color information of the first color information. ### Claim 12 (depends on 11) The calibration method of a projection system of claim 11, wherein the obtaining the target color information of the second color information according to the color space coordinate in the second color information is according to a color space coordinate of the full white pattern generated by the at least one solid-state light-emitting device with the highest one of the plurality of output powers. ### Claim 13 (depends on 11) The calibration method of a projection system of claim 11, wherein the first color information comprises a plurality of color space coordinates sensed by the first light sensor when the at least one solid-state light-emitting device emits the plurality of white lights with the plurality of output powers. ### Claim 14 (depends on 11) The calibration method of a projection system of claim 11, wherein the second color information comprises a plurality of color space coordinates sensed by the second light sensor when the at least one solid-state light-emitting device projects the plurality of full white patterns with the plurality of output powers. ### Claim 15 (depends on 11) The calibration method of a projection system of claim 11, wherein each of the first color information and the second color information comprise a plurality of color space coordinates. ### Claim 16 (depends on 11) The calibration method of a projection system of claim 11, wherein the corresponding relationship between the first color information and the second color information is a straight-line relationship or an Nth-order polynomial relationship. ### Claim 17 (depends on 11) The calibration method of a projection system of claim 11, wherein the light source control signals comprise a plurality of current signals input to the at least one solid-state light-emitting device.