Patent ID: 8170650

Claim:
A medical device for sensing cardiac events, comprising: a plurality of light sources capable of emitting light at a plurality of wavelengths; a detector to detect the emitted light; a processor to generate an ambient light measurement in response to ambient light detected by the detector, generate a plurality of light measurements in response to the emitted light detected by the detector, and adjust the plurality of light measurements in response to the ambient light measurement; and wherein the processor is configured to adjust a light source of the plurality of light sources in response to one of a first ambient light measurement and a second ambient light measurement being greater than an ambient threshold, and, in response to the one of the first ambient light measurement and the second ambient light measurement not being greater than the ambient threshold, stores the first ambient light measurement, the second ambient light measurement, and an intensity of light emitted by the light source of the plurality of light sources detected at the detector.