# US 11,307,308 B2 · Tracking device and electronic device with improved work surface adaptability > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,307,308 B2 - Document ID: US11307308B2 - Status: Granted - Kind: B2 - Application number: 17/185,263 - Filed: 2021-02-25 - Published: 2021-06-17 - Granted: 2022-04-19 - Earliest claimed: 2017-06-02 - Assignees: Pixart Imaging Inc. - Applicants: PixArt Imaging Inc. - Inventors: Hui-Hsuan Chen; Cheng-Lin Yang; Tzu-Yu Chen - Web page: https://patentgrep.com/patent/US11307308B2 ## CPC - G01S 17/66: Tracking systems using electromagnetic waves other than radio waves - G01S 7/4808: {Evaluating distance, position or velocity data} - G01S 7/4815: {using multiple transmitters} - G01S 7/4816: {of receivers alone} - G01S 17/46: Indirect determination of position data - G01S 17/50: Systems of measurement based on relative movement of target - G06T 7/521: from laser ranging, e.g. using interferometry; from the projection of structured light - H04N 23/51: Housings - H04N 23/56: provided with illuminating means - G01S 17/08: for measuring distance only (indirect measurement G01S17/46; active triangulation systems G01S17/48) - G01S 17/48: Active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves - G06T 2207/10004: Still image; Photographic image - G06T 2207/10152: Varying illumination - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A tracking device including an image sensor, a light source and a processor is provided. The image sensor senses reflected light or scattered light formed by the light source illuminating a work surface. The processor calculates a trace of the tracking device according to one of the reflected light and the scattered light that generates more apparent image features so as to increase the adaptable work surfaces. ## Claims ### Claim 1 A tracking device, configured to detect displacement with respect to a work surface, the tracking device comprising: an image sensor configured to output image frames; a partially reflective plate; a first light source configured to emit light toward the work surface to generate scattered light that impinges on the image sensor without passing through the partially reflective plate; a second light source configured to emit light toward the partially reflective plate to generate partial reflected light perpendicular to the work surface, and the partial reflected light impinges on the image sensor after being reflected by the work surface; and a processor configured to compare image features of the image frames being captured when the first and second light sources are lighting, and turn on, in calculating the displacement, one of the first and second light sources whose associated image frame has a better image feature. ### Claim 2 (depends on 1) The tracking device as claimed in claim 1, wherein the first light source and the second light source are turned on simultaneously. ### Claim 3 (depends on 1) The tracking device as claimed in claim 1, wherein the partially reflective plate is a plastic plate or a glass plate. ### Claim 4 (depends on 1) The tracking device as claimed in claim 1, wherein the first light source is a light emitting diode or a laser diode, and the second light source is a light emitting diode. ### Claim 5 (depends on 1) The tracking device as claimed in claim 1, wherein the image sensor is arranged not to receive a main reflected light beam of the first light source. ### Claim 6 (depends on 1) The tracking device as claimed in claim 1, further comprising a lens arranged between the image sensor and the partially reflective plate. ### Claim 7 (depends on 1) The tracking device as claimed in claim 1, wherein the partially reflective plate is arranged under the image sensor in a longitudinal direction, and the second light source is arranged adjacent to the partially reflective plate in a transverse direction. ### Claim 8 (depends on 1) The tracking device as claimed in claim 1, further comprising a housing, wherein the partially reflective plate is arranged upon an opening of the housing. ### Claim 9 (depends on 1) The tracking device as claimed in claim 1, wherein the partial reflected light impinging on the image sensor passes through the partially reflective plate again after being reflected by the work surface. ### Claim 10 An electronic device, configured to be operated on a work surface, the electronic device comprising: a first light source, configured to emit light at a tilt angle and toward the work surface to generate a main reflected light beam; a partially reflective plate; a second light source, arranged adjacent to the partially reflective plate in a transverse direction; an image sensor, not arranged at a path of the main reflected light beam of the first light source and arranged above the partially reflective plate in a longitudinal direction; and a processor configured to compare image features of image frames captured by the image sensor when the first and second light sources are lighting, and turn on, in calculating displacement, one of the first and second light sources whose associated image frame has a better image feature. ### Claim 11 (depends on 10) The electronic device as claimed in claim 10, wherein the first light source is a light emitting diode or a laser diode, and the second light source is a light emitting diode. ### Claim 12 (depends on 10) The electronic device as claimed in claim 10, further comprising a lens arranged between the image sensor and the partially reflective plate. ### Claim 13 (depends on 10) The electronic device as claimed in claim 10, wherein the first light source and the second light source are turned on simultaneously. ### Claim 14 (depends on 10) The electronic device as claimed in claim 10, wherein the partially reflective plate is a plastic plate or a glass plate. ### Claim 15 (depends on 10) The electronic device as claimed in claim 10, further comprising a housing, wherein the partially reflective plate is arranged upon an opening of the housing.