Real-time non-destructive testing of dynamic holograms in doubly-doped LiNbO_3 crystals using phase-conjugate technique

摘要

To test the dynamic photorefractive grating during holographic recording, as usual, the signal wave is blocked from time to time and simultaneously the diffracted beam of the reference wave is tested. This kind of measurement destroys the continuity of the holographic recording and increases the random noise and results in bad repeatability and reliability. In this paper, the phase-conjugate technique is used to overcome the above drawbacks. The reference wave and the object wave are much stronger than the probe beam propagating along the counter-direction of the reference wave. Thus the real-time and non-destructive testing of the dynamic holograms can be obtained by measuring the phase-conjugate wave of the object wave.