Research on light signals extraordinary compressed using periodic structure modulated method in photorefractive materials

摘要

During some high processing, such as high-speed photography and so on, the encode pulse or driving signal must be compressed with full optics system. According to the light speed can be slowed down in a photorefractive crystal bar in which written volume-index grating by two laser beam, so as to the light signal may be transmitted in slow speed under 1/ 7 of light speed in vacuum. Because the genesis of the phenomenon is the inner index periodic structure, so the out put signal compressed may be realized through erasing the periodic structure in the opposite direction of signal beam using another laser beam when the signal light transmitting the crystal bar. However , every finite signal stream can be further compressed by the same way again. Different erasing method would get many kinds of out put signal to adapt to various design.