Optimal design method of subwavelength metal polarization beam splitting grating

Abstract

The present invention provides an optimal design method of subwavelength metal polarization beam splitting grating, which can effectively settles the parameter confirming problem of subwavelength metal polarization beam splitting grating. Firstly the splitter period lambada is confirmed according to the period condition of subwavelength beam splitting grating. Then the variation relationship of effective refractive index and duty cycle of grating of TE polarization and TM polarization are confirmed with an effective medium theory, and the duty cycle f of grating is confirmed according to the required effective refractive index. Finally, the groove depth h of grating is confirmed according to the 1/4 wavelength matching principle of film optical anti-reflection. The optimal design method of subwavelength metal polarization beam splitting grating provided by the invention settles the problem for optimizing multi-grating parameter combination in designing, and increases the scientificity, reliability and timeliness of designing.

Description

technical field [0001] The invention belongs to the field of grating design, and relates to an optimal design of a polarization beam splitting grating, in particular to a subwavelength metal polarization beam splitting grating optimization design method, which simplifies the design method of the subwavelength metal polarization beam splitting grating and improves the grating The polarization beam-splitting performance is of great significance. Background technique [0002] With the continuous advancement of micro-processing technology, sub-wavelength metal gratings with a period less than 100nm can now be produced. Sub-wavelength metal gratings only have 0-order diffraction, stable diffraction efficiency, excellent polarization beam splitting characteristics, small size, high efficiency, and easy integration. The core component of optical components has broad application prospects in optical communication, optical measurement, optical information processing, liquid crystal ...

AI Technical Summary

Problems solved by technology

The traditional empirical analysis method is mainly based on the strict vector electromagnetic theory to calculate the diffraction efficiency of the grating under different parameters, and manually determine the optimal design parameters of the grating. This method cannot solve the multi-parameter combination of grating period, duty ratio, and groove depth For optimization problems, local optimal solutions are often obtained, and parameter selection errors may be caused by human factors.

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