Incoherent-to-coherent conversion by use of the photorefractive beam-fanning effect and amplification by two-wave coupling have been demonstrated experimentally in a photorefractive Ba<sub>1−<i>x</i></sub>Sr<sub><i>x</i></sub>TiO<sub>3</sub> crystal. The converted coherent image is amplified by 60×. The resolution of the amplified coherent image is ~28 line pairs/mm. A notable advantage of the method is that incoherent-to-coherent conversion and coherence amplification of the converted coherent image are realized simultaneously in a photorefractive crystal.
© 2001 Optical Society of America
(140.4480) Lasers and laser optics : Optical amplifiers
(160.5320) Materials : Photorefractive materials
(190.7070) Nonlinear optics : Two-wave mixing
(230.6120) Optical devices : Spatial light modulators
Yishen Qiu, Zhiqiang Zheng, Tuansun Lu, Wenchai Huang, J. Zhuang, and D. Y. Tang, "Incoherent-to-Coherent Conversion by Use of the Photorefractive Beam-Fanning Effect and Amplification by Two-Wave Coupling in a Photorefractive Ba1−xSrxTiO3 Crystal," Appl. Opt. 40, 687-690 (2001)