Patent ID: 6337741
Filing Date: 2002-01-08
Classification: G02B

Abstract:
A sensor system for measuring the light absorption in a target, comprising:a light source adapted to emit light within a chosen range of wavelengths; a light receiver adapted to detect light within a chosen range of wavelengths, a partially reflective beam splitter adapted to transmit light from said light source, and to reflect light to said light receiver, a lens with a chosen focal length transmitting light between said light source and said light receiver, characterized in that the beam splitter comprises a first reflecting part and a second transmitting part being different from said first reflecting part, and a shield being positioned between said transmitting part and said light source, and that said first reflecting part of the beam splitter is positioned closer to said light source than said second part of the beam splitter, the shield protruding from a border between said parts towards said lens.