Based on the results of the coupled-wave theory the diffraction efficiency is calculated for thick phase transmission holographic gratings taking into account the chemical processing of the recording material. Three effects of processing are considered: variations in the average refractive…

The experimental results of diffraction efficiency as a function of the geometrical disposition of recording beams in bleached silver halide transmission thick-holographic gratings are presented. Two variables have been used to relate these results with certain geometric parameters. These variables…

A new model to describe the influences of chemical processing on thick holograms is presented. The model is based on three hypotheses about the behaviour of holographic recording material during processing. Thickness variations and shear-type effects that are due to…

Silver halide sensitized gelatin (SHSG) is one of the most promising techniques for the fabrication of transmission holographic optical elements, achieving relatively high sensitivity of photographic material with the low scattering and high light stability of dichromated gelatin. In this…

We propose a two step method which enables us to obtain transmission Holographic Optical Elements of high diffraction efficiency as well as a good signal-to-noise relation. By means of a device using partially coherent light, a master Holographic Optical Element…

Equations are derived for determining third-order wavefront aberrations in the plane of the exit pupil from the known aberration in the plane of a holographic lens. Using the transformation equations of wavefront aberration when the plane of the exit pupil…

A statistical model is used to study the formation of noise gratings in holograms and the mechanism that causes radiation scattering in them. The theoretical model presented describes noise scattering in terms of diffraction due to the high number of…

Recording noise gratings with single-beam exposures in bleached silver halide emulsions is used as a holographic spectroscopy technique in order to analyse and optimize photochemical processing. In particular, rehalogenating type bleachings are analysed by measuring the transmittance through the recorded…

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STUDY OBJECTIVE: The aim was to investigate the association between mothers' occupational exposure during pregnancy and the incidence of acute lymphoblastic leukaemia in children. DESIGN: The study was a case-control investigation. A face to face interview was used to assess…