DESIGN METHOD FOR HIGH-RESOLUTION SPECTROGRAPH AND SPECTROGRAPH

摘要

A design method for a high-resolution spectrograph and a spectrograph. The spectrograph is constructed by using a concave grating (G), two entrance slits (A1, A2) and an optical detector (B1B2). The method includes the following steps: 1) determining values of a wavelength λ2 and a wavelength λ3, and dividing the whole spectrum detection range into two waveband ranges; 2) according to a principle that the two waveband ranges are multiplexed into one optical detector, determining a relational expression between two incidence angles via a grating equation satisfied by the incidence angles of the two entrance slits; 3) determining that recording structure parameters and usage structure parameters are obtained; 4) determining manufacturing parameters of the concave grating according to the recording structure parameters to obtain a concave grating satisfying applications; and 5) determining positions of the two entrance slits and the optical detector relative to the concave grating according to initial values of the usage structure parameters, thus constructing a spectrograph. The spectrograph obtained through the design method can improve the resolution in most spectrum areas.