Patent ID: 8492699

Claim:
A photodetector configured for use as an ambient light sensor (ALS) having a spectral response similar to that of a human eye, comprising: one or more first photodiode regions that are covered by an optical filter configured to reject infrared (IR) light and that produce a first current (I 1 ); one or more second photodiode regions that are covered by a light blocking material configured to reject visible and IR light and that produce a second current (I 2 ); one or more third photodiode regions that are not covered by the optical filter configured to reject IR light and are not covered by the light blocking material and that produce a third current (I 3 ); and circuitry configured to produce an output indicative of the first current (I 1 ) or a scaled version of the first current (I 1 ), minus the second current (I 2 ) or a scaled version of the second current (I 2 ), minus the third current (I 3 ) or a scaled version of the third current (I 3 ); wherein when light including visible light and IR light is incident on the photodetector a portion of the IR light passes through the optical filter configured to reject IR light, the first current (I 1 ) produced by the one or more first photodiode regions is primarily indicative of the visible light and a first fraction of the portion of the IR light that passes through the optical filter, the second current (I 2 ) produced by the one or more second photodiode regions is primarily indicative a second fraction of the portion of the IR light that passes through the optical filter, the third current (I 3 ) produced by the one or more third photodiode regions is primarily indicative of both the visible light and the IR light, and the output produced by the circuitry is primarily indicative of the visible light with a majority of the IR light that passes through the optical filter subtracted out, and thus has a spectral response similar to that of a human eye, thereby enabling the photodetector to be used as an ALS.