Recording holograms in luminescent materials

The fluorescein-boric acid glass organophosphor has been characterized as a transient photochromic hologram receptor medium in which an excited electronic state gives rise to the holographic grating. It is shown that the holographic signal depends upon dye concentration, sample thickness, and writing laser power. The decay rate of the hologram, after the writing laser is turned off, is determined by the excited state lifetime of 1 sec, while holographic rise times are in the order of 0.1 sec. Diffraction efficiencies are in excess of 0.2% at hologram writing powers of about 500 mW cm(-2). It is thought that this can be improved by choice of either more highly doped systems or pure materials.