Investigation on the optical focusing effect of Fresnel biprism  

作　　者：ZHANG Yingtao LI Hongguo 

机构地区：[1]Technical College for the Deaf,Tianjin University of Technology,Tianjin 300384,China [2]School of Science,Tianjin University of Technology,Tianjin 300384,China

出　　处：《Optoelectronics Letters》2023年第3期151-154,共4页光电子快报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.11604243);the Natural Science Foundation of Tianjin (No.16JCQNJC01600);the Foundation of Tianjin University of Technology (No.ZD21-12)。

摘　　要：Fresnel biprism has been applied to the design of plasmonic meta-lenses recently. In order to promote these applications and understand the physics behind them, in this paper we investigate the focusing effect of Fresnel biprism from the perspective of information optics and geometrical optics. The expression for optical field intensity describing the focusing effect of Fresnel biprism is derived according to the relationship between the impulse response function and the optical field. Then the formula of the focal length is achieved. Furthermore, the Fresnel biprism focusing experiment is performed. Specially, the optical field intensity distribution is measured and the corresponding intensity along the axis is obtained. The results show that the focusing effect depends on the base angle, refractive index and base length of the biprism. There exists axial resonance effect in the axial intensity. The experimental results are in accordance with the theoretical results. These results could be valuable to the applications of Fresnel biprism in designing large depth of focus plasmonic meta-lenses.

关 键 词：FIELD FRESNEL EFFECT 

分 类 号：TH74[机械工程—光学工程]