Patent ID: 6570652
Filing Date: 2003-05-27
Classification: G01J,G02B,H04B,H04J

Abstract:
A device for monitoring wavelength division multiplexed optical signals, comprising:a structure for supporting components of the device; an optical component supported at one end of the structure for transmitting the optical signals; a diffraction grating supported at an opposing end of the structure for diffracting the optical signals from the optical component; an optical sensor supported in relation to the diffraction grating by the structure for monitoring the optical signals; a lens assembly supported by the structure and disposed between the optical sensor and the diffraction grating, the lens assembly having a focal length for focusing the optical signals in relation to the optical sensor; and wherein the coefficient of thermal expansion of the diffraction grating is a value chosen to be approximately equal to a negative of a change of index of refraction of air with temperature.