title: Two-dimensional angular filtering by volume Bragg gratings in photothermorefractive glass.
abstract: We propose and perform two-dimensional angular filtering on the basis of volume Bragg gratings (VBGs) in a series connection for cleaning up a laser beam. The dependence between angular selectivity and VBG parameters is analyzed with the coupled wave theory. Near-field modulation, contrast ratio, and power spectral density were used to evaluate the effect of filtering in both the spatial and frequency domain. The results from our initial experiments showed that the near-field modulation and contrast ratio of laser beam were remarkably improved.
authors.affiliation: Wuhan National Laboratory for Optoelectronics, School of Optoelectronic Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
authors.forename: Xiao
authors.initials: X
authors.lastname: Yuan
authors.forename: Shang
authors.initials: S
authors.lastname: Wu
authors.forename: Jiansheng
authors.initials: J
authors.lastname: Feng
authors.forename: Kuaisheng
authors.initials: K
authors.lastname: Zou
authors.forename: Guiju
authors.initials: G
authors.lastname: Zhang