Contribution of Holographic Amplitude and Phase Gratings in Phase Conjugate Interferometry.

某些类型的染料掺杂薄膜已被用作全息图，其中通过吸收系数或折射率或两者的不可逆光化学变化记录干涉图案。在纯振幅和相位全息图中，与读取波的相位相比，衍射波的加性相位分别为0和π/2，而在混合全息图中，加性相位可能取一个中间值，但取决于物体和参考波的振幅。这个附加相位可以加到目标波的本征相位中，因此在全息干涉和相位共轭干涉中，事先知道附加相位的值是很重要的。结果表明，在低衍射效率的情况下，加性相呈恒定值。提出了一种测量混合全息图重建波的加性相位的方法。加性相位是通过测量两个衍射波在具有两个读波的移动全息图照射下强度变化的对比度和延迟来确定的。我们用一些黄原染料和螺球染料掺杂的薄膜验证了所提方法的有效性。

Some kinds of dye-doped-films have been used as a hologram in which an interference pattern is recorded through an irreversible photochemical change in absorption coefficient or refractive index, or both of them. In pure amplitude and phase holograms, the diffracted waves have the additive phase of zero and π/2, compared with the phase of the reading wave, respectively, while, in a mixed hologram, the additive phase may take a intermediate value but depends on the amplitudes of the object and reference waves. This additive phase may be added to the intrinsic phase of the object wave, so that in holographic and phase conjugate interferometries, it is important to know beforehand the value of the additive phase.We showed that the additive phase takes a constant value for low diffraction efficiency. We proposed how to measure the additive phase of the wave reconstructed from a mixed hologram. The additive phase is determined by measuring the contrast and the delay of the intensity changes of the two diffracted waves under the illumination of a moving hologram with two reading waves. We verified the validity of the proposed method by using some xanthen-dye- and spiro-dye-doped films.