Holographic magnifier

Claim 1

A method of making a holographic magnifier comprising: splitting a plane wave front of monochromatic spatially coherent light into first and second plane wave fronts; directing the first plane wave front towards a first photosensitive side of a photographic plate; converting the second plane wave front into a divergent spherical wave front; directing the spherical wave front towards the other photosensitive side of the photographic plate, and periodically changing the angle at which said spherical wavefront impinges on said photographic plate such that the origin of said spherical wavefront scans a plane situated parallel to and at a fixed distance away from said plate; the step of directing said first plane at which said plane wavefront impinges on said plate such that the direction of propagation of said plane wavefront is always normal to a sphere whose origin is at the center of the photographic plate, each direction of said plane wavefront corresponding to one angle at which said second wavefront impinges on said plate such that said plane wavefront makes a fixed minimum angle with respect to the plane of said plate when the origin of said spherical wavefront is at an end point of its scan in any direction and is normal to said plate when the origin of said spherical wavefront is normal to the center of said plate; exposing said photographic plate to said plane and spherical wave fronts for each corresponding position of said wavefronts to produce a plurality of latent fresnel diffraction patterns; developing said photographic plate to produce said plurality of fresnel diffraction patterns; whereby when said developed photographic plate is positioned parallel to and at said fixed distance away from the face of a cathode-ray tube, an image on said tube when viewed through said developed plate is magnified. 2. The method of making a holographic magnifier as set forth in claim 1 wherein the second plane wave front is converted into a spherical wave front by: channeling the second plane wave front into the entrance of an optical fiber having a diameter small enough to convert the light exiting therefrom into a point source producing a spherical wave front.