| 摘要 |
941,773. Photo-electric exposure control in photographic printing. AGFA A. G. March 17, 1960 [March 26, 1959], No. 9533/60. Heading G2A. [Also in Division G1] In photographic projection printing apparatus optical means are provided for focusing an image of the exit pupil of the projection lens on to a photo-cell or diffusing screen in front thereof. Blue, red and green light is selected from lamps 7, 8, 9, Fig. 3, respectively by the interference filters 10, 11 and passed through the negative 13, a projection lens 22 and to the printing paper 3. A portion of the light is reflected by a mirror 23 and by means of filters 27, 28, a field lens 32 forms blue, red and green images of the exit pupil of lens 22 on diffusing screens 29, 30, 31 to control the exposure in known manner. The face 33 of lens 32 lies in the focal plane of lens 22. For ease of access, cells 24, 25, 26 are in a unit, Fig. 2, having three sides 41, 42, 43 which is detachable from a unit having sides 38, 39, Fig. 1, containing filters 27, 28 and screens 29, 30, 31. The light sources are in a drawer 35 and exposure regulators in a housing 37. |
