Interference Spectral Imaging Based on Liquid Crystal Relaxation and Its Application in Optical Component Defect Detection

Jiajia Yuan,He Cheng,Wei Fan,Tongyao Du,Dajie Huang

doi:10.3390/app12020718

Abstract

In this paper, we propose a fast interference spectral imaging system based on liquid crystal (LC) relaxation. The path delay of nematic LC during falling relaxation is used for the scanning of the optical path. Hyperspectral data can be obtained by Fourier transforming the data according to the path delay. The system can obtain two-dimensional spatial images of arbitrary wavelengths in the range of 300–1100 nm with a spectral resolution of 262 cm−1. Compared with conventional Fourier transform spectroscopy, the system can easily collect and integrate all valid information within 20 s. Based on the LC, controlling the optical path difference between two orthogonally polarized beams can avoid mechanical movement. Finally, the potential for application in contactless and rapid non-destructive optical component defect inspection is demonstrated.

Highlights

Precision optical components have a wide range of applications in many fields
We consider whether spectral imaging based on liquid crystal (LC) can be used in optical component defect detection
In order to improve the spectral resolution by using multiple reflections to increase the optical path difference, Huang obtained a resolution of 1 nm @ 630 nm [18]

Summary

Introduction

Precision optical components have a wide range of applications in many fields. The quality of optical elements directly affects the performance of the whole optical system. We consider whether spectral imaging based on LC can be used in optical component defect detection. In order to improve the spectral resolution by using multiple reflections to increase the optical path difference, Huang obtained a resolution of 1 nm @ 630 nm [18].

Results

Conclusion