Apparatus and method for driving diffraction gratings

摘要

A grating drive apparatus (100) for use in a multiple-grating spectrometer (500) is provided. The spectrometer has an entrance slit (521), an exit port (550), an optical path (525) between the entrance slit and the exit port, and a plurality of diffraction gratings (237-239). Each of the gratings is rotatable about a respective preferred axis for selecting a wavelength during spectrometer operation. The grating drive apparatus includes a turret (200) having a plurality of gratings mounted on it, a mechanical stop assembly (300), and a drive assembly (400). The drive assembly causes the turret to engage the stop assembly to rotate the turret and select a grating. The drive assembly also rotates the selected grating to select an operational wavelength. <IMAGE>