Multi-orientated wire-grid polarizer and its application to polarization navigation

作者：Chu Jin Kui^*; Wang Zhi Wen; Zhang Ying Jie; Wang Yin Long

来源：Optics and Precision Engineering, 2012, 20(10): 2237-2244.

DOI：10.3788/OPE.20122010.2237

• Alignment error
• Angular errors
• Back propagation neural networks
• BP neural networks
• Compensation algorithm
• Discrete components
• Extinction ratios
• Grating periods
• Metal layer
• Nano wire polarizer
• Navigation sensors
• Rigorous coupled wave analysis
• Wire grid polarizers

Multi-orientated bi-layered nano wire polarizers were fabricated in a polycarbonate (PC) substrate to eliminate the alignment error caused by the discrete components. The polarizers were used in a polarization navigation sensor, the angular error was tested and the angular error compensation algorithm based on neural network was analyzed. First, the bi-layered nano wire polarizers were designed using Rigorous Coupled Wave Analysis (RCWA) and the effects of grating period and metal layer thickness on the polarizer performance were analyzed in detail. Experiments show that the polarizer has TM transmittance of 71% and extinction ratio of 2100 for the wavelength of 518 nm. The polarizer was fabricated based on nanoimprint lithography and six polarizers were mounted in the substrate with the same structure but different orientations. After that, the polarizer was applied to a polarization navigation sensor and the angular error was measured at a measurement platform. Results indicates that the original angular error is within ±1°, but it is ±0.2° when is compensated by using Back Propagation (BP) neural network compensation algorithm. The proposed polarizer could fulfill the needs of polarization navigation systems.

• 出版日期2012