Fiber optic bundle beam expander with image intensifier

Claim 1

A biocular viewing system comprising: a. a sealed housing in a periscope configuration having an input section and an output section, said input section and said output section at opposite ends of said housing; b. a right angle prism mounted within said housing adjacent said input section; c. objective lens means; d. an iris positioned between said right angle prism and said objective lens means, rays from an object to be viewed being directed to said objective lens means through said right angle prism and said iris, said rays forming an image at the focus of said objective lens means; e. image intensifier means having input and output sections, an image focused on said input section by said objective lens means, an amplified image presented at said output section; f. unidirectional fiber optic bundle beam expander means including fiber optic bundle means and unidirectional diffuser means, said fiber optic bundle means having input and output faces, said unidirectional diffuser means formed in said output face at an image plane of said fiber optic bundle means, said fiber optic bundle means having a numerical aperture that is less than unity, said amplified image at said output section being directed towards said input face and being transmitted to said output face by said unidirectional fiber optic bundle means, said unidirectional diffuser means operative to spread unidirectionally the energy in the numerical aperture of said fiber optic bundle means for biocular viewing of said image; and g. biocular eyepiece means in optical registration with said unidirectional fiber optic bundle beam expander means, said biocular eyepiece means presenting said unidirectionally spread image at said output face for biocular viewing.