Adjustment and control of playback wavelength of Lippmann hologram recorded in methylene-blue sensitized dichromated gelatin

In this paper, we present a new technique for adjusting and controlling the playback wavelength of Lippmann holograms recorded in methylene-blue sensitized dichromated gelatin (MBDCG). During the preparation of photosensitive layer, a water-soluble organic reagent, acrylamide is added homogeneously into our optimum MBDCG recipe as preswelling reagent. It will be dissolved completely into water during the postprocessing procedure and result in the uniform shrink of the fringe planes of reflection hologram, which will makes the playback wavelength shift relatively to shorter wavelength. This method can be applied to adjust the playback wavelength of reflection hologram quantitatively by changing the concentration ofpreswelling reagent.