# US 10,119,858 B2 · Lens for pet rejecting passive infrared sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,119,858 B2 - Document ID: US10119858B2 - Status: Granted - Kind: B2 - Application number: 15/900,221 - Filed: 2018-02-20 - Published: 2018-06-21 - Granted: 2018-11-06 - Earliest claimed: 2014-12-30 - Assignees: Google Inc. - Applicants: Google LLC - Inventors: Anurag Gupta; Aveek Ravishekhar Purohit - Web page: https://patentgrep.com/patent/US10119858B2 ## CPC - G01J 1/0411: {using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction} - G01J 1/0266: {Field-of-view determination; Aiming or pointing of a photometer; Adjusting alignment; Encoding angular position; Size of the measurement area; Position tracking; Photodetection involving different fields of view for a single detector} - G01J 1/44: Electric circuits {(for command of an exposure part G03B7/02)} - G02B 3/0006: {Arrays (G02B3/02, G02B5/188 take precedence)} - G02B 3/08: with discontinuous faces, e.g. Fresnel lens {(diffractive Fresnel lenses G02B5/1876)} - G08B 13/193: using focusing means - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G08B: SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS ## Abstract A passive infrared motion detection sensor that includes a Fresnel focusing arrangement that creates at least a first infrared sensing region, a second infrared sensing region, and a third infrared sensing region, in which target detection in one or more infrared sensing regions is weighted to be distinguishable from target detection in remaining infrared sensing regions. The Fresnel focusing arrangement creates the weighted infrared sensing regions using a lenslet region, an optically opaque region and a plurality of extruded cylindrical lenslets that extend across a portion of both the lenslet region and the optically opaque region. The signal detection in at least the second weighted infrared sensing region, for example, an infrared sensing range between 6 and 10 feet, is weighted to easily distinguish between a pet within the second infrared sensing range and a person at any infrared sensing range. ## Claims ### Claim 1 A system comprising: an infrared detector; a lens arrangement to focus infrared radiation from a target onto the infrared detector, the lens arrangement comprising: an optically opaque region, a lenslet region, and a plurality of extruded cylindrical lenslets, extending across a portion of both the lenslet region and the optically opaque region, wherein the lens arrangement forms a far field relative intensity pattern onto the infrared detector, the far field relative intensity pattern comprising at least a first region, a second region, and a third region, and wherein the focused infrared light from the second region is weighted with respect to the light in at least one of the first region and the second region by the lens arrangement, wherein the weighting is due to an infrared light gathering strength of the second region that corresponds to a sensing distance range of the detector. ### Claim 2 (depends on 1) The system of claim 1, wherein the first region corresponds to the sensing distance range of the detector selected from the group consisting of: between 10 and 20 feet, and between 0 and 20 feet. ### Claim 3 (depends on 1) The system of claim 1, wherein the second region corresponds to the sensing distance range of the detector of between 6 to 10 feet. ### Claim 4 (depends on 1) The system of claim 1, wherein the infrared light gathering strength of the lens arrangement for the second region is less than that for the first region. ### Claim 5 (depends on 1) The system of claim 1, wherein the third region corresponds to a sensing distance range of the detector of between 0 to 6 feet. ### Claim 6 (depends on 1) The system of claim 1, wherein the infrared light gathering strength of the lens arrangement for the third region is less than that for the second region. ### Claim 7 (depends on 1) The system of claim 1, wherein the detector distinguishes between a pet and a person using the second region, wherein a maximum signal generated by the detector based on the received infrared light from the pet at a range of interest is exceeded by a minimum signal generated by the detector based on the received infrared light from the person. ### Claim 8 (depends on 1) The system of claim 1, wherein a target in the weighted second region is distinguishable from a target in the first region. ### Claim 9 A method comprising: focusing infrared radiation from by a target onto an infrared detector with a lens arrangement, the lens arrangement comprising: an optically opaque region, a lenslet region, and a plurality of extruded cylindrical lenslets that extend across a portion of both the lenslet region and the optically opaque region; forming, with the lens arrangement, a far field relative intensity pattern onto the infrared detector, the far field relative intensity pattern comprising at least a first region, a second region, and a third region; and weighting the focused infrared light from the second region with respect to the light in at least one of the first region and the second region by the lens arrangement, wherein the weighting is due to an infrared light gathering strength of the second region that corresponds to a sensing distance range of the detector. ### Claim 10 (depends on 9) The method of claim 9, wherein the first region corresponds to the sensing distance range of the detector selected from the group consisting of: between 10 and 20 feet, and between 0 and 20 feet. ### Claim 11 (depends on 9) The method of claim 9, wherein the second region corresponds to the sensing distance range of the detector of between 6 to 10 feet. ### Claim 12 (depends on 9) The method of claim 9, wherein the infrared light gathering strength of the lens arrangement for the second region is less than that for the first region. ### Claim 13 (depends on 9) The method of claim 9, wherein the third region corresponds to the sensing distance range of the detector of between 0 to 6 feet. ### Claim 14 (depends on 9) The method of claim 9, wherein the infrared light gathering strength of the lens arrangement for the third region is less than that for the second region. ### Claim 15 (depends on 9) The method of claim 9, wherein the detector distinguishes between a pet and a person using the second region, wherein a maximum signal generated by the detector based on the received infrared light from the pet at a range of interest is exceeded by a minimum signal generated based on the received infrared light by the detector from the person. ### Claim 16 (depends on 9) The method of claim 9, wherein a target in the weighted second region is distinguishable from a target in the first region.