High-speed alignment optimization of digital optical phase conjugation systems based on autocovariance analysis in conjunction with orthonormal rectangular polynomials

Published

August 28, 2018

Author(s)

Ashton S. Hemphill, Yuecheng Shen, Jeeseong C. Hwang, Lihong V. Wang

Abstract

Digital optical phase conjugation (DOPC) enables many optical applications by permitting focusing of light through scattering media. However, DOPC systems require precise alignment of all optical components, particularly of the spatial light modulator (SLM) and camera, in order to accurately record the wavefront and perform playback through the use of time-reversal symmetry. We present a digital compensation technique to optimize the alignment of the SLM in five degrees of freedom, permitting focusing through thick scattering media with a thickness of 5 mm and transport scattering coefficient of 2.5mm^-1 while simultaneously improving focal quality, as quantified by the peak-to-background ratio, by several orders of magnitude over an unoptimized alignment.

Citation

Journal of Biomedical Optics

Volume

24

Issue

3

Pub Type

Journals

Download Paper

https://doi.org/10.1117/1.JBO.24.3.031004

Local Download

Keywords

digital phase conjugation, DOPC, time-reversal conjugation, spatial phase control, focusing through scattering medium, spatial light modulator, SLM, wavefront correction, auto covariance analysis

Citation

Hemphill, A. , Shen, Y. , Hwang, J. and Wang, L. (2018), High-speed alignment optimization of digital optical phase conjugation systems based on autocovariance analysis in conjunction with orthonormal rectangular polynomials, Journal of Biomedical Optics, [online], https://doi.org/10.1117/1.JBO.24.3.031004, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=925673 (Accessed October 9, 2025)