Paper
18 December 2019 Design of multilayer film polarization-independent gratings
Author Affiliations +
Proceedings Volume 11336, AOPC 2019: Nanophotonics; 113360F (2019) https://doi.org/10.1117/12.2547457
Event: Applied Optics and Photonics China (AOPC2019), 2019, Beijing, China
Abstract
Laser beam combining technology currently plays an important role in optical systems. The combined beam grating is the most important realization component inside, so it is necessary to study the beam grating. Conventional metal gratings have high absorbance, and the damage threshold of metal gratings is usually not high. Multilayer dielectric film gratings are necessary for research because they have almost no absorption and high damage thresholds at the same time as high diffraction efficiency. Based on the theory of rigorous coupled wave (RCWA), a multilayer dielectric film grating model is established and a multilayer dielectric film grating with a center wavelength of 1053 nm is designed in the paper After a series of optimal design, the following results are obtained. Ta2O5 and SiO2 are selected as multi-layer material, and the multi-layer structure is S(HL)^12HTA .The groove density is 1480 lines/mm. The profile of grating grooves is rectangular .The duty cycle of surface relief structure is between 0.3-0.4, the groove depth is between 750-850nm, the sum of residual thickness and groove depth is between 930-1030nm.The -1st diffraction average efficiency of the grating is over 95% at the Littrow angle (51.2 degrees).Wavelength bandwidth greater than 40nm.The diffraction efficiency is the same as that of a metal grating .At the same time, the laser induced damage threshold can be improved.
© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Xu Chen, Chaoming Li, Xinrong Chen, Yanling Guo, Qing Xu, and Yong Xu "Design of multilayer film polarization-independent gratings", Proc. SPIE 11336, AOPC 2019: Nanophotonics, 113360F (18 December 2019); https://doi.org/10.1117/12.2547457
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Diffraction gratings

Diffraction

Optical design

Multilayers

Dielectrics

Reflectivity

Refractive index

Back to Top