Abstract

Optical properties of radially polarized light generated by liquid crystal (LC) polarization-converting devices with two LC molecular orientations $(\pm 180°$ and $\pm 90°$ twist modes) are measured and the applicability to optical wavelet transforms (WTs) are discussed. It is found that the radially polarized lights in both the $\pm 180°$ and $\pm 90°$ twist modes can be regarded as wavelets. Based on the principle of WT, feature extractions of a simple binary image are carried out by applying the LC polarization-converting device to a shadow-casting system. Unique feature extraction properties of the shadow-casting system using the LC polarization-converting device and a LC microlens array are discussed. It is experimentally confirmed that edge and corner features are successfully extracted using the LC polarization-converting device with $\pm 180°$ and $\pm 90°$ twist modes, respectively.

© 2006 Optical Society of America

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