Abstract

Holograms that are highly resistant to optical erasure can be recorded in lithium niobate using thermal fixing or multiphoton techniques. In interferometry, such holograms have the potential of serving as permanent reference holograms and thus reducing double-exposure interferometry to single-exposure interferometry. We have recently applied this technique using thermally fixed reference holograms in iron-doped crystals of lithium niobate. First, the reference scene is recorded as a Fourier transform hologram and thermally fixed in the crystal. Then, in the same crystal volume, a hologram of the scene of interest is superimposed. Reconstruction reveals the output interferogram. These initial experiments indicate the feasibility of this approach.

© 1987 Optical Society of America