Dividing Diffraction Pattern of Rotating Grating into Three Portions and Studying Each Portion Respectively

The phenomena of the rotating grating have been studied and have the varieties application. The diffraction normal order that is at the intersection of the grating’s normal vector and the screen is introduced and is the function of the incident angle of light, the grating spacing and wavelength.

We suggest the following: (1) the diffraction normal order and the zeroth order () divide a diffraction pattern into three portions; each portion corresponds to a range of diffraction orders, , , , and is described by specific equation, respectively; (2) the number of the diffraction orders “m” in each portion is determined by the incident angle of light, the grating spacing, and wavelength;

(3) the diffraction angles and positions of the diffraction orders of each portion can be presented in terms of and ; (4) the diffraction pattern of a rotating grating is non-uniform.