A commonly used configuration for a monochromator that takes advantage of the linear dispersion of a diffraction grating is the Czerny-Turner Monochromator. In this design, the input radiation is collimated by a mirror and directed onto the diffraction grating. The collimated broadband source radiation is then dispersed by the diffraction grating, and the different wavelengths are spread out over many different angles. Some range of wavelengths (dependent on the incident angle and exiting angle from the grating) are collected by the second mirror and focused onto the exit aperture. The linear dispersion of the grating, as well as the size of the exit aperture of the instrument determine the resolution of the optical measurement.

By pivoting the grating, the incident angle of the collimated source onto the grating and the exiting angle of the diffracted light that is collected by the second mirror changes. Pivoting the grating, therefore, provides a mechanism for changing the wavelength that appears at the exit aperature. The dispersion of a diffraction grating is linear with respect the sine of the exiting angle. This relationship can be taken advantage of to provide a simple mechanism for scanning the wavelength at the exit aperture of the monochromator, the sine-bar drive.