Patent ID: 6667803
Filing Date: 2003-12-23
Classification: A61B,G01J,G01N,G02B

Abstract:
A spectrophotometric instrument including:a source of measurement light signals having measurement light wavelengths; a source of a calibration light signal at a calibration detection wavelength which is different than the measurement light wavelengths; a probe having: one or more send fibers coupled to the measurement and calibration light signal sources for transmitting the measurement light signals and the calibration light signal into tissue, and one or more receive fibers for receiving light from tissue including the measurement light signals and the calibration light signal; a calibration device adapted for receiving the probe and having an optical filter for transmitting the measurement light signals but not the calibration light signal; a detector coupled to the receive fibers for generating electrical signals representative of the light received at the receive fibers; and a processor/controller coupled to the detector for initiating a calibration procedure when the: calibration light signal is not detected.