GB504211A - Improvements in or relating to photographic cameras having photoelectric exposure meters - Google Patents

Abstract

504,211. Photo-electric photographic exposure meters. ZEISS IKON AKT.-GES. Jan. 11, 1938, No. 915. Convention date, Jan. 13, 1937. [Class 40 (iii)] [Also in Group XX] A photographic camera comprises a photo. electric exposure meter in which the measuring instrument indicating the. photo-electric current is operatively connected with a mirror adapted to deflect a light beam in accordance with the deflections of the measuring instrument, and which includes means for bringing said light beam to a definite direction or for adjusting an indicator in accordance with the direction of said light beam, said means being operatively coupled with an exposure adjustment member of the camera so that said member is adjusted upon operation of said means. In the form shown, a moving coil galvanometer fitted with mirror 4 is electrically connected to the exposure meter 9 and with a variable resistance the adjusting member of which is coupled with the time adjustment member. The mirror 5 is rotatable and is mechanically coupled with the diaphragm-adjustment member of the camera. Light proceeding from the object to be photographed is used as an indicating beam, enters by the window 1 and is finally thrown on to-the scale 6 to be observed. In operation, the time adjustment member is set which adjusts the resistance, and the mirror 5 is moved to bring the light pointer to a predetermined position on the scale 6. This automatically sets the stop opening. Instead of the time adjustment member being connected with the mirror 5 it may be connected to an auxiliary indicator to be brought into a definite position with relation to the light beam on the scale 6. The auxiliary pointer may be a second light beam thrown on to the screen from a separate mirror that is connected to an adjustment member, the two beams being brought to coincidence. Concave mirrors may be used to form a spot on the screen.