We have given the principles and illustrations for the manufacture of the high frequency grating and low frequency grating achieved through the parallelogram method and the Michelson method,respectively.

Analysis on the incidence errors of color separation grating used for ICF;

The real-time measurement by two-frequency grating;

Li and Yasuyuki successively proposed two different two-frequency gratings used for three-dimensional surface profilometry.

Through theoretic analysis and numerical simulations, it is proved that the optimum thickness of PTR Bragg grating exists, and its diffraction efficiency increases with the decrease of grating frequency and wavelength bandwidth.

In order to increase the number of available fiber lasers,meanwhile guarantee the diffraction efficiency to be at some high level,the grating frequency f should be chosen betwe.

CCD is used in double-frequency grating shearing interferometer to measure the time and space coherence of light field quantitatively and spherical aberration of gradient-index rod lens.

An interferometric technique with double-frequency grating used to measure the thermal lensing of a Ti: sapphire rod pumped with Ar￣+ laser axially is presented.