Diffractive angle-invariant superlattice suitable for dual background refractive index

CN119861439BActive Publication Date: 2026-07-03NANJING UNIV OF SCI & TECH

Patent Information

Authority / Receiving Office: CN · China
Patent Type: Patents(China)
Current Assignee / Owner: NANJING UNIV OF SCI & TECH
Filing Date: 2024-12-30
Publication Date: 2026-07-03

AI Technical Summary

Technical Problem

Existing meta-gratings perform well under a single background refractive index environment, but their diffraction performance changes significantly under multiple background refractive index environments, making it difficult to maintain a consistent diffraction angle, which affects their application in fields such as grating sensors and biomedicine.

Method used

A meta-grating suitable for dual background refractive indices is designed. By setting appropriate period length, diffraction order and incident wavelength, the width, height and gap width of the nanopillars are optimized using a particle swarm optimization algorithm to maintain the same diffraction angle in air and water media. The diffraction efficiency is optimized using an adaptive function.

Benefits of technology

It achieves consistency of diffraction angle in both air and water media for metagratings, improves the accuracy and flexibility of beam deflection, expands its application range, and meets diverse application needs.

✦ Generated by Eureka AI based on patent content.

Smart Images

Figure CN119861439B_ABST

Patent Text Reader

Abstract

The application discloses a diffraction angle invariant superstructure grating suitable for double background refractive indexes, which comprises a nanocolumn unit and a substrate unit; a plurality of nanocolumn units are sequentially arranged on the substrate unit according to a set period length, the nanocolumn unit comprises a plurality of rectangular nanocolumns, and gaps exist between the nanocolumns. Based on the design principle of a grating equation, the diffraction order, the period length and the incident light wavelength of the superstructure grating are optimized and selected according to different background media, the best structure parameters are designed by combining an optical simulation tool and an optimization algorithm, and finally the function of keeping the same diffraction angle in air and water environments is realized. The superstructure grating realizes the efficient diffraction and deflection of light beams in different backgrounds by adjusting the subwavelength periodic structure, and simultaneously has flexible design freedom, so that the light beams can be deflected to a specified target angle.

Need to check novelty before this filing date? Find Prior Art