Abstract: The redirection of light by holographic glazing is based on diffraction. The intensity and the color of the redirected light depend strongly on the direction of the diffracted waves. The paper presents a model for the design of volume holograms as light directing elements which takes into account the 3D character of the diffraction process. Formulas for the Bragg- wavelength, the bandwidth, and the diffraction efficiency are given. It is shown how to use conventional photometric formulas in order to calculate the illuminance and the color distribution on surfaces illuminated by the diffracted light. Finally, the design method is demonstrated for a single volume grating incorporated into a window as a light directing element.!8
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