초록 ▼

A method and system for recording and displaying grazing-incidence (i.e., steep reference beam angle) holograms supported on a substrate having thin edge-illuminatable geometry. The system and process of the present invention uses thin edge-illuminated substrates that facilitate optimal coupling of

A method and system for recording and displaying grazing-incidence (i.e., steep reference beam angle) holograms supported on a substrate having thin edge-illuminatable geometry. The system and process of the present invention uses thin edge-illuminated substrates that facilitate optimal coupling of the reference light beam at steep angles approaching grazing incidence. Different recording techniques are employed when the index of refraction of the substrate is greater than that of the recording medium, than when the index of refraction of the substrate is less than that of the recording medium.

대표청구항 ▼

[ What is claimed is:] [7.] A system for illuminating a volume hologram having slanted fringes comprising:a substrate of thin construction, made from an optically transparent material having an index of refraction n.sub.S, said substrate having front and rear surfaces disposed substantially parallel

[ What is claimed is:] [7.] A system for illuminating a volume hologram having slanted fringes comprising:a substrate of thin construction, made from an optically transparent material having an index of refraction n.sub.S, said substrate having front and rear surfaces disposed substantially parallel to each other, and an edge surface disposed between said front and rear surfaces;a holographic recording medium made from an optically transparent material having an index of refraction n.sub.M greater than n.sub.S with the difference of index of refraction therebetween equal to .DELTA.n, said holographic recording medium having front and rear surfaces and a volume hologram with slanted fringes prerecorded therein, and said rear surface of said holographic recording medium being disposed in direct physical contact with the front surface of said substrate along an interface; anda light source for producing an illumination beam which propagates along a single-pass optical path extending through said substrate at a grazing angle of incidence .O slashed..sub.s of at least about 80 degrees with respect to the normal to said interface, so that said illumination beam couples into said holographic recording medium and interacts with said slanted fringes, wherein said index of refraction of said substrate n.sub.S is matched to the index of refraction of said holographic recording medium n.sub.M by selecting values for n.sub.S and n.sub.M so that the difference of index of refraction therebetween .DELTA.n is functionally related to said grazing angle of incidence .O slashed..sub.s and the index of refraction of said substrate n.sub.S by the expression: ]EQU18 ]