Optical reflection grating, method of optimizing such a grating and optical spectrometer

摘要

Optical reflection grating has multitude of parallel grooves. If ratio of grating period (g) to wavelength ( lambda ) is less than 0.7, the groove depth (T) is selected such that the diffraction efficiencies for transverse electric (TE) and transverse magnetic (TM) waves of a certain wavelength ( lambda ) differ by less than 5%. The diffraction efficiencies of TE and TM waves are above 60%. Independent claims are also included for the following: (a) Optical spectrometer; (b) Method for finding an optical reflection grating with almost equally high diffraction efficiency for TE and TM waves of certain wavelength