This paper proposes an experimental research method for the wavelength demultiplexing technology that is based on volume holographic grating in photorefractive LiNbO3 crystal and studies the important factors that affect the grating diffraction efficiency.In this experiment

o-ray optical write in and e-ray readout are used when the write-in beam intensity ratio is nearly 1∶1.The experiment is successfully performed by writing into the grating in the same location with red and green lights successively and then reading out with coupled light.No interferences occur when the included angle between the two gratings is 0.18 °.