Analysis and Calculation on Transmission Efficiency of Two-channel Elliptical Crystal Spectrometer

摘要

Two-channel elliptical crystal spectrometer (TCECS) is very important diagnostic instrument for research on thermonuclear fusion controlled by laser, time and space resolution can be detected simultaneously for x-ray, space resolution is recorded by x-film or x-CCD in one channel, time resolution is recorded by x-streak camera in another channel. Transmission efficiency of TCECS is dependent upon reflective ratio of cylindrical mirror, integrated reflectivity of crystal, transmissivity of filter foil, and spectrographic aperture ratio. This paper analyzes influencing factors of transmission efficiency; reflectivity of cylindrical mirror is decided by coated material, grazing incident angle and x-ray wavelength; integrated reflectivity of crystal is decided by crystal material and x-ray wavelength; transmissivity of filter foil is decided by its material, thickness, and x-ray wavelength. Using Matlab 6.1 software does numerical calculation .for all influencing factors, it is indicated that transmission efficiency will decrease when x-ray wavelength increases.