GB850498A - Improvements in photographic cameras with built-in exposure meters - Google Patents

Abstract

850,498. Photographic camera viewfinders. AGFA A. G. July 3, 1958 [July 9, 1957], No. 21401/58. Class 98(1) In a camera having a built-in exposure meter, means are provided for reflecting into the viewfinder the galvanometer needle of the meter, and also image field demarcations. The camera shown has a viewfinder objective 9 and eyepiece 10, into which eyepiece a second rangefinder image, from an aperture 12, is reflected via a mirror 13, pivoted lens 14, lens 15, and semi-transparent mirror 11. The image field demarcations are formed by apertures in a plate 21, and are reflected into the viewfinder by a mirror 25, lens 26, and mirror 11. (Mirror 25 has a central opening 27 to allow passage of the light rays for the second rangefinder image.) The galvanometer 4 of the exposure meter is rotatably mounted, and is coupled by a lever 41 to control the aperture and shutter speed. The galvanometer needle 31 projects into an aperture 30 in a stepped part 29 of a cover plate 28. The aperture 30 is spaced from the bifocai lens 16 at the same distance as is the demarcations plate 21, and its image is seen in the viewfinder through a cut-out portion 34 of the mirror 25. An inspection window 35 in the cover 2 provides illumination for the needle and aperture 30. On looking into the viewfinder eyepiece 10, there appear, in addition to the subject to be photographed, the field demarcations, and images of aperture 30 and the needle point. A fixed reference index is provided, to which the needle point can be adjusted by adjustment of the regulating members for the diaphragm aperture and shutter speeds.