Abstract

It was pointed out that an inexpensive commercial available liquid crystal TV can be operated as a binary phase-only spatial light modulator by orienting the second analyzer to be perpendicular to the bisector of the two transmitted polarization states of the LCTV.¹ Therefore, it is possible to use the device to correct the phase nonuniformity of the device itself, as well as other phase distortion in the optical system. We employ the so-called point diffraction interferometer² to examine the phase distortion. The interference pattern captured by a CCD camera is then binarized and sent back to the LCTV by using a computer. A ±π phase shift is therefore effectively added to the LCTV to restore the nonuniform phase. It must be mentioned that the system operates in an on-line and closed loop architecture which enables the optimum phase correction mask to be generated. Moreover, the interferometer does not require high quality optical components to produce the interference pattern, and the phase restored system can be immediately utilized in some image processing applications, such as binary phase-only joint transform correlation.

© 1989 Optical Society of America