Beyond the partial light intensity imager: eliminating Moiré patterns

Authors

Yuanhe Tang, University of Wollongong
Qingsong Liu, Xi'an University of Technology
Yong Wu, Xi'an University of Technology
Yang Yu, Xi'an University of Technology
Xusan Yang, Xi'an University of Technology
Haiyang Gao, Xi'an University of Technology
Xiaolin Wang, University of WollongongFollow

RIS ID

101848

Publication Details

Tang, Y., Liu, Q., Wu, Y., Yu, Y., Yang, X., Gao, H. & Wang, X. (2015). Beyond the partial light intensity imager: eliminating Moiré patterns. Optics Communications, 355 143-147.

Abstract

A partial light intensity imager (PLII) was proposed in our previous research for enhancing the dynamic range to 2.2x10⁵ lx in strong light. Moiré patterns may occur, however, since the PLII employs both a liquid crystal display (LCD) and a charge-coupled device (CCD) camera as its key devices, which can be regarded as two gratings. This research calculates the fringe widths and spectra for both the LCD and the CCD, and analyzes the relationship between the fringe width and the applied voltage on each pixel of the LCD. According to the theoretical results, we find that changing the rotational angle of the liquid crystal (LC) molecule by regulating the applied voltage is an effective method to eliminate the Moiré patterns in the PLII. Based on this principle, an experiment has been designed, and the Moiré patterns fringe width is alleviated from 20 pixels to10 pixels distance before and after, and the results verify the correctness of the theoretical analysis.