Patent ID: 7099057

Claim:
A method of fabricating a holographic mask comprising the steps of: a) providing an illumination source for generating a coherent illumination beam directed along an axis; b) providing a non-opaque object mask having substantially planar regions capable of transmitting a portion of said illumination beam as undiffracted reference wavefronts, and having one or more substantially transparent elements for creating overlapping object wavefronts when said illumination beam is incident thereon; c) disposing said object mask in said illumination beam; d) providing a holographic recording medium in said illumination beam in line optically with said object mask, wherein said holographic recording medium has an area; e) illuminating said object mask with said illumination beam, wherein said illumination beam directed along said axis causes said object mask to allow said transmitted undiffracted reference wavefronts to pass therethrough to reach reach said area, and wherein said illumination beam directed along said axis causes said one or more substantially transparent elements to create said object wavefronts which interact with said undiffracted reference wavefronts to create an interference pattern at said area; and f) recording said interference pattern in at least said area of said holographic recording medium.