| 摘要 |
973, 341. Photo-electric photometers. AGFA A.G. Nov. 22,1960 [Nov. 25, 1959], No. 40182/60. Heading G1A. [Also in Division H1] A photometer comprises a photovoltaic cell and a photoresistor located on a common electrically conducting base plate for exposure to illumination, and so connected electrically that variation in illumination causes variation in the resistance of the photoresistor to vary the effective loading of the photovoltaic cell. The photovoltaic cell 6, Fig. 3, is shunted by a photoresistor 7 and fixed resistors 10,11 to produce a deflection on a galvanometer 8 which varies as the logarithm of the illumination on the elements 6 and 7. In a simpler embodiment, Fig. 2, (not shown) resistors 10 and 11 are omitted. The photometer may be incorporated in a photographic camera or an exposure meter. The components indicated by the chain line 25 may be formed as an integrated circuit (see Division H1). |
