GB671655A - Improvements in photographic reflex cameras - Google Patents

Abstract

671,655. Reflex photographic cameras provided with range-finders. BOLSEY, J. Oct. 8, 1946 [Dec. 31, 1940], No. 30034/46. Class 98 (i). A reflex camera is provided with a short home base range-finder having one of the basedefining reflectors coupled to the camera objective, the said two reflectors being situated so that the beam accepted by one is passed in a direction parallel to the front wall of the casing to the other across the beam incident on or reflected from the reflex focusing mirror and then to a viewing aperture in the rear wall of the casing, the focusing mirror beam forming no part of the range-finder system. As shown, a reflex camera 10 having a translucent viewing screen 15 surrounded by a wall 29, has apertures above and on opposite sides of the objective 12, and a viewing window 26 in the rear wall of the camera in line with one of the apertures, the light beam from the other aperture being reflected to the windows by a pivotallymounted reflector 22 coupled to the objective and a stationary reflector 24. The reflected beam may pass either between the wall 29 and the front wall 14 of the camera or through apertures in the wall 29 above or below the screen 15. The Specification as open to inspection under Sect. 91, states that the coupling between the objective (which need not be that of a reflex camera) and the pivotally-mounted range-finder reflector may be by means of an arm as 34 attached to the reflector following either an eccentric cam ring, as 35, or a cam of varying thickness carried by the objective. Alternatively, there may be provided a manually rotatable shaft carrying worms of different pitches, one engaging a toothed ring on the objective and the other the arm connected to the reflector. The range-finder may be exchangeably mounted on the lens board or each interchangeable lens may have its own rangefinder mounted on a common support. A combined coupled range-finder and view-finder for alternative usage may be provided. Two slotted members 36, 41 slidable on retaining- pins 38, 43 carry respectively a view-finder eyelens 39, range-finder mirror 24 and lens 40; and a view-finder field lens 44. The movements of the slidable members are co-ordinated by a pivoted lever 45 having rounded ends engaging in notches 47 in both members. This subject-matter does not appear -in the Specification as accepted.