LENS FOR PET REJECTING PASSIVE INFRARED SENSOR

摘要

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.

主权项

1. A system, comprising:
an infrared detector; and a Fresnel focusing arrangement, comprising:
an optically opaque region,a lenslet region having a first plurality of lenslets, anda second plurality of lenslets, wherein the second plurality of lenslets extends across both the lenslet region and the optically opaque region,wherein the Fresnel focusing arrangement is configured to:produce a far field relative intensity pattern by weighting received infrared radiation, andfocus the far field relative intensity pattern onto the infrared detector.