基于光折变LiNbO3晶体中体光栅的各向异性衍射特性,从理论上分析了利用单个体光栅实现波分解复用技术的方案。在此方案中,采用He-Ne 激光束记录一个特定波数的光折变体光栅,就能够实现远程通信波长在1550 nm附近的波长解复用,理论上可以实现的解复用波段范围是从1400 nm到1650 nm。由于采用了各向异性衍射,衍射光和读取光的偏振方向互相正交,提高了信噪比; 另外,方案中仅需记录单个光栅就可以实现波分复用,克服了多重光栅复用方案中记录时间复杂性的问题。

Based on anisotropic diffraction of volume grating in the photorefractive LiNbO3 crystal, an optical wavelength demultiplexing (WdeM) scheme implemented by a single volume grating is theoretically discussed. By only one grating written by two He-Ne laser beams at a specific wavenumber, the scheme can realize wavelength demultiplexing around telecommunication wavelength 1550 nm, and the theoretical possible wavelength suitable for WDM is from 1400 nm to 1650 nm. For anisotropic diffraction, the polarization of diffracted and readout beams are orthogonal to each other, which can largely improve the signal-to-noise ratio. Besides, only one grating written in the crystal can avoid time-writing complexity in the multiple grating writing.