抄録
This paper describes a real-time visualization method for birefringence distribution using the correlation image sensor (CIS). The sensing principle is based on heterodyne imaging interferometry. The imaging system simultaneously demodulates the retardation and orientation distributions of a birefringent material from the amplitude and phase of an incident heterodyne interference pattern at an ordinary frame rate of the CIS. An experimental system is composed of a 64×64-pixel three-phase CIS camera and a two-frequency He-Ne laser with a beat frequency of 25 kHz. Experimental results obtained with a Babinet-Soleil compensator and a quarter-wave plate reveal that the measurement accuracy of the proposed imager is less than 5° in orientation and 3.5° in retardation. Imaging applications to a transparent plastic sheet and a liquid-crystal display panel are also demonstrated.
