PHOTOREFRACTIVE HOLOGRAPHIC LENSES AND APPLICATIONS FOR DYNAMIC FOCUSING AND DYNAMIC IMAGE SHIFTING

Wavelength-multiplexed reflective holographic lenses were recorded in a 1-mm-thick Fe-doped LiNbO3 crystal. A simple theoretical model based on Kogelnik's coupled-wave theory and Kuktarev's photorefractive-mate rial equations was used to characterize the photorefractive lenses in terms of Bragg-limited field of view, optimum space-bandwidth-product, and wavelength selectivity. Experimental measurement verified the the oretical calculations. An f/3 lens was recorded, and nearly aperture-l imited diffraction performance was observed. Applications of wavelengt h-multiplexed photorefractive lenses were shown by demonstration of dy namic focusing and lateral image shifting.