The invention discloses a method for calibrating the spectral
wavelength of an optical
grating rotary light splitting
spectrograph. The method is characterized in that a relation between the
optical wavelength and reading of an optical
encoder is derived by using an optical
grating equation working under a Littrow condition, and a theoretical calibration model is established; spectral
wavelength calibration is carried out by using a two-point equation solving method; and finally, initial
wavelength positioning is carried out by using calibration parameters in order to ensure the consistency in target position when different spectrographs measure gratings with the same wavelength. The method disclosed by the invention has the advantages that (1) the calibration steps are simple and effective, and the calibration
workload and the calculation amount are reduced under the premise of ensuring the calibration precision; (2) the calibration work can be completed by only using two standard light sources with different wavelengths under the premise of ensuring the accuracy of the wavelength, the calibration time is short, the calibration efficiency is high, and the calibration cost is low; and (3) the calibration model is established through known theories,
curve fitting is not required to be adopted, factors, which influence calibration, among different spectrographs are considered comprehensively, calibration is carried out more reasonably and more feasibly, and the calibration precision is higher.