Method of designing double incident slit spectrometer and double entrance slit spectrometer

摘要

A method for designing a double-entrance slit spectrograph and a double-entrance slit spectrograph. A concave grating (G), two entrance slits (A1, A2) and two optical detectors (B1B2, B1'B2') are used to construct the spectrograph. The method comprises the following steps: 1) determining an incidence angle of the first entrance slit and a groove profile period of the concave grating; 2) estimating a blaze angle of the concave grating, and determining a surface material and a groove profile structure of the concave grating; 3) estimating the range of the incidence angle, and acquiring a wavelength-diffraction efficiency curve of the concave grating under multiple angles distributed within the range of the incidence angle when the incidence angle is θA1; 4) determining the value of an incidence angle θA2, the value of a wavelength λ2 and the value of a wavelength λ3; 5) obtaining a recording structure parameter and a using structure parameter; 6) determining the making parameter of the concave grating; and 7) determining the positions of the two entrance slits and the two optical detectors with respect to the concave grating, so as to obtain the spectrograph via construction. The spectrograph obtained by this design method can improve the diffraction efficiency in most of the spectrum areas.