光折变多重体光栅的制作及应用

Fabrication and Application of Photorefractive Multiple Volume Gratings

根据光折变多重体光栅的滤波原理,在10×10×10mm3的LiNbO3∶Fe晶体中利用循环曝光法写入了光栅波矢夹角为0.037°且衍射效率均衡的8重体光栅,实验上证实了光写入多重光折变体光栅应用于波分复用系统的可行性.利用LiNbO3∶Fe晶体制作了一个原理性双通道波分复用器,成功地实现了对相同方向入射的波长分别为635nm和650nm的两束光的有效分离,并根据布喇格条件,将光折变体光栅应用于光波波长的测量,测量精度可达10pm量级.

Based on the filtering principle of photorefractive multiple volume gratings, superposition of eight volume gratings at the angle 0. 037 degree between the grating wave vectors in the LiNbO3 ： Fe crystal with size of 10×10×10mm^3 has been obtained by using incremental recording method. Those gratings have approximately the same diffraction efficiency. So the application of multiple volume gratings in wavelength demultiplexing system is demonstrated by the experiment. Furthermore, a double wavelength filter using the LiNbO3 ： Fe crystal has 635 nm and 650nm illuminating the volume gratings successfully. According to the Bragg condition, the light wave, and the measurement accuracy can reach been made. Two light beams with the wavelength of in the same direction have been separated by the filter volume grating is used to measure the wavelength of the order of 10 pm.