Newly Developed Imaging Application by High-speed Polarization Camera

Abstract

In the past 80 years, high-speed image sensors have been applying to various applications such as microscopy, strain measurement, and spectroscopic temperature measurement. On the other hand, by classifying those applications according to a three-element of the light, polarization has hardly been used until now. In the polarization measurement field, since polarization modulation techniques featuring a rotating polarizer, a photoelastic modulator and a liquid crystal enabled the quantification, they have successfully applied to a thickness measurement system, a shape measurement system and a birefringence measurement system. On the other hand, because currently established systems have employed time modulation, it is difficult to apply them to dynamic phenomena. In order to overcome this problem, a high-speed polarization imaging method has been developed that can measure two-dimensional polarization by single photo-detection. An element technology of High-speed Polarization Image Sensor (HSPIS) has been designed and fabricated. It is composed of a pixelated polarizer array and parallel read out circuits with a multi-channel analog to digital converters. Parallel read out pixels have been connected directly with each polarizer in order to achieve higher sampling rate of two-dimensional polarization detection. In this paper, the basic principle of the HSPIS and its application are introduced.