Full characterization of holographic reflection gratings recorded on BB640 emulsions.

A complete characterization of unslanted holographic reflection gratings with high diffraction efficiency recorded on ultrafine grain emulsion BB640 has been achieved. By use of a wavelength-dependent absorption coefficient, the diffraction efficiency, the replay wavelength, and the spectral bandwidth of each recording has been obtained. Corresponding index modulation, absorption, and effective thickness have been obtained with high accuracy by fitting the experimental data with Kogelnik's theory.

One-dimensional photonic crystals with an amplitude-modulated dielectric constant in the unit cell.

Photonic band structures of one-dimensional photonic crystals with an amplitude-modulated dielectric constant in the unit cell were studied. With this structure two bandgaps in the visible and one in the IR region were predicted. Experimental measurements of the two photonic bandgaps in the visible spectrum were made in a photonic crystal recorded in a holographic emulsion.

Multiple band holographic reflection gratings recorded in new ultra-fine grain emulsion BBVPan.

We present the results obtained using the new panchromatic ultra-fine grain emulsion BBVPan, manufactured by Colourholographics Ltd., to produce multiple band holographic reflection gratings, multiplexed on a single layer of material. Three different laser systems were used: He-Cd, frequency-doubled Nd-YAG and He-Ne.

Nonlinear effects on holographic reflection gratings recorded with BB640 emulsions.

Nonlinear recording effects on holographic re ection gratings recorded on BB640 emulsions have been studied. Using an analytical approach to the characteristic curve of this emulsions, the density profiles recorded in the developed emulsions that correspond to the original light pattern generated by the holographic setup have been obtained. The final spatial profiles of the refraction index resulting from different exposure levels and different bleaching processes have been evaluated studying the experimental diffraction efficiency and comparing it with Kogelnik's theory.

Comparison of direct, rehalogenating, and solvent bleaching processes with BB-640 plates.

Bleaching is one of the key processes in the production of phase holograms with fine grain silver halide emulsions. This step was widely studied for discontinued Kodak, Agfa, and Ilford emulsions, and most of those results have been optimized with small changes for presently available holographic emulsions. A study of the different bleaching techniques with BB-640 holographic emulsions is presented.