Patent Document ID: 9250135
Application ID: 13419410
Patent Status: 1

Claim One:
1. A flame detector comprising: an infrared sensor having a pixel array with a plurality of pixels; a lens situated at a first distance from the infrared sensor, where light passes through the lens to the pixel array; and a long wave infrared filter spaced from the infrared sensor, wherein the long wave infrared filter is situated a second distance from the infrared sensor that is different than the first distance and is configured to filter long wave infrared radiation from substantially all of the light passing through the lens to the plurality of pixels of the pixel array; and wherein: infrared radiation from a scene promulgates through the lens and the filter, in either order, to the infrared sensor; and wherein long wave infrared radiation of the infrared radiation from the scene between the filter and the infrared sensor has a magnitude less than the magnitude of mid wave infrared radiation of the infrared radiation from the scene between the filter and the infrared sensor.