Paper
14 November 2014 An improved opto-digital joint transform correlator reducing the influence of defocus on image motion measurement
Hui Zhao, Hongwei Yi, Jingxuan Wei, Xiaopeng Xie
Author Affiliations +
Abstract
Joint transform correlator (JTC) is a highly efficient way to measure image motion and a hybrid opto-digital JTC (HODJTC) has been proposed by us in [CHIN. OPT. LETT., Vol. 8, No. 8]. Being different from the traditional JTC, only one optical Fourier transform is needed and the optically generated joint power spectrum (JPS) is used to compute the image motion in a digital way. Although a high measurement precision can be obtained through HODJTC, the defocus will counteract the final result. In this paper, the influence of defocus is analyzed and an improved HODJTC, whose sensitiveness to defocus is reduced, is proposed. By introducing randomly generated defocus, a series of cross-correlation peak images is obtained and a subsequent spatial averaging procedure is applied to these images to generate the final cross-peak image which is used to compute the defocus invariant motion value.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Hui Zhao, Hongwei Yi, Jingxuan Wei, and Xiaopeng Xie "An improved opto-digital joint transform correlator reducing the influence of defocus on image motion measurement", Proc. SPIE 9273, Optoelectronic Imaging and Multimedia Technology III, 92731C (14 November 2014); https://doi.org/10.1117/12.2064959
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Motion measurement

Fourier transforms

Joint transforms

Optical correlators

Digital imaging

Spatial light modulators

Modulation

Back to Top