Recent improvements in solid state CW lasers, recording materials and light sources (such as LED lights) for displaying colour holograms are described. Full-color analogue holograms can now be created with substantially better image characteristics than previously possible. To record ultra-realistic images depends on selecting the optimal recording RGB laser wavelengths. Analogue color holograms of the Denisyuk type are the ones which really create the illusion of viewing a real object behind the plate rather than an image of it. It is necessary to use extremely low-light-scattering panchromatic recording materials, which means the use of ultra-fine-grain, silver-halide emulsions. The third factor is the light source used to display the recorded color holograms. Progress in illumination technology, by employing the new LED lights, is leading to a further major reduction in display noise and to a significant increase of the clear image depth and brightness of the holograms. Recording and displaying color holograms (referred to as OptoClones™) of museum artefacts are described.
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