Patents Represented by Attorney Lester H. Hallacher

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  • Light box having a Fresnel lens
    Patent number: 4704004
    Abstract: A light box comprises a source of light, a reflector and a Fresnel lens. The lens provides nearly constant illumination of an object such as a liquid crystal cell by collimating light parallel to a normal to the cell. Thus the cell will exhibit a nearly uniform electro-optical response. The reflector preferably is parabolic, while the light source preferably is a line source such as a fluorescent tube.
    Type: Grant
    Filed: July 30, 1986
    Date of Patent: November 3, 1987
    Assignee: RCA Corporation
    Inventor: Richard W. Nosker