| 摘要 |
766,775. Photographic copying. ILFORD, Ltd. Feb. 22, 1955 [March 19, 1954]. No. 8156/54. Drawings to Specification. Class 98(1) In copying a photographic transparency having a dyestuff image the image is optically projected on to light-sensitive material by a projector utilizing a substantially parallel light beam obtained from a small light source, the transparency also being illuminated by at least one secondary light beam which, unless deviated by the transparency, will not pass through the projection objective. In this way the effect of scratches &c. in diffusing light out of the projection beam can be compensated by light scattered into it, So as to pass through the projection objective, from the secondary beams. The relative intensities of the projection and secondary beam(s) may be controlled by varying the aperture of the objective with a diaphragm or by a grey filter in the main beam. The Provisional Specification also contains the subject matter of Specification 766,776. |
