title: High-spectral-resolution characterization of broadband high-efficiency reflection gratings.
abstract: An optical characterization method with high spectral resolution for broadband, multilayer dielectric gratings working at the -1st reflection order is demonstrated in this paper. The diffraction-efficiency measurement setup for the broadband gratings with high efficiencies mainly consists of a double-light-path system with a monochromator as the illumination source and an automatic rotation stage for incident and diffraction angles adjustment. Two typical practical difficulties, namely (1) the mismatch between the spot size of diffracted light and the limited detector aperture and (2) the shared propagation path between the incident and diffracted light at the Littrow angle, were well solved. A fabricated multilayer dielectric grating was measured on the established measurement setup. Diffraction efficiencies greater than 90% in the wavelength range from 763 to 852 nm were obtained with an average relative deviation less than 1.0%. At the moment, the wavelength resolution is 1 nm and the angle resolution is 0.2 deg. The high-resolution broadband diffraction spectrometry testing method is applicable to characterizing broadband pulse compression gratings in the laser systems.
authors: Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China.
authors: Kai
authors: K
authors: He
authors: Jianpeng
authors: J
authors: Wang
authors: Yongqiang
authors: Y
authors: Hou
authors: Xu
authors: X
authors: Li
authors: Heyuan
authors: H
authors: Guan
authors: Fanyu
authors: F
authors: Kong
authors: Shijie
authors: S
authors: Liu
authors: Yunxia
authors: Y
authors: Jin
authors: Kui
authors: K
authors: Yi