Improving stability of coaxial holographic optical correlation system using a simple disk structure

Abstract

Optical correlation systems have been developed as hardware that is useful for high-speed and large-scale data analysis. Among them, our system using the disk-type hologram is promising because it can effectively utilize the control techniques of conventional optical disks. In previous work, however, we used a very simple disk structure consisting of a mirror substrate, photopolymer, and cover glass, and tracking control was not performed. Consequently, it was difficult to stably record a large amount of data in the long range of the circumference since the hologram recording position deviates from the disk circumference due to surface deflection and eccentricity attributed to rotation without tracking controls. In this study, we aim to stabilize the optical correlation system by introducing a new disk structure and conventional servo control. We confirmed that both sufficient correlation signal and servo control signals can be detected with the simple disk structure due to the signal detection principle of the optical correlation.