<title>Multicolor Holography</title>

Abstract

Two and three primary colors derived from an He-Ne gas laser and an Argon gas laser can be employed in recording and reconstructing holo-grams. For the tri-color case, it is possible to reconstruct a three-dimensional multi-color image which possesses almost all the natural hues of the original object. Each wavelength generates an independent fringe system that is recorded on a photographic film or plate. Due to the interrelationship between the three fringe systems during reconstruction, six ghost images are generated which are deleterious to the reconstructed image. Several techniques to control the ghost images were developed, some of which will be discussed. Emphasis will be placed on the technique which uses the three-dimensional properties of the recording medium. In the recon-struction, each fringe system diffracts light in a manner satisfying the Bragg relation for a particular reconstructing wavelength. If the reconstruction wavelengths are the same as the original wavelengths used to record the fringe system, the result is a multi-color reconstruction possessing few or no ghost images.