| 摘要 |
1,125,877. Apparatus and process for making holograms. INTERNATIONAL BUSINESS MACHINES CORP. May 10, 1967 [June 20, 1966], No. 21722/67. Headings G2A and G2C. A method of making a hologram of an object (10), Fig. 1 (not shown) comprises illuminating the object; forming a plurality of images thereof on a first sheet 16 (Fig. 5. ) of photographic emulsion with an array 12 of lenses (14); developing the first sheet; directing a first beam of coherent light from a source 18 through the developed sheet 16 and the lens array 12 on to a second sheet 20 of photographic emulsion, directing a second beam of coherent light from a source 22 directly on to the sheet 20 simultaneously with the first beam of coherent light to interfere therewith; and developing the second sheet to produce the required hologram. When exposing the first and second sheets, the first sheet 16 is spaced a distance f from the lens array corresponding to the focal length of the lenses (14), the array 12 being a fly's eye lens sheet. The second beam 22 may be directed as shown on to the second sheet, or alternatively the first and second beams are directed simultaneously on to opposite sides of the second sheet, Fig. 4 (not shown) to provide a hologram reconstructable in white light, in which case the second sheet is also spaced a distance f from the lens array during exposure. The first sheet may be affixed to a plane surface of the fly's eye lens sheet, or to one of the plane surfaces if the array comprises two such fly's eye lens sheets joined together. Full colour reconstructed images may be obtained by illuminating the object with white light, and then exposing the second sheet to first and second beams of one colour, third and fourth beams of a second colour, and fifth and sixth beams of a third colour. The developed sheet 16 may be illuminated by a source (26), Fig. 6 (not shown) to give, via the lens array, a vertical image having three-dimensional properties, a movable projection screen (24) being provided to be located in various cross-sections of the image.
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