| 摘要 |
1,232,435. Exposure meter. NIPPON KOGAKU K.K. July 16, 1968 [July 20, 1967], No.33880/68. Heading G2A. A bridge circuit in an exposure meter comprises a photo-cell 2 in series with a diode 3 forming two arms of the bridge, a variable resistance 5 for setting an exposure factor and a second diode 4 forming the other two arms. The change #i in the current through an indicator across the bridge in response to a doubling or halving of the incident illumination is shown to be constant over a wide range. Indicating marks 11, 12 may be placed on either side of a nullmark 10 of a galvanometer indicator so that an estimate of the "wrongness" of the exposure setting can be obtained and it may be arranged that the "correct" setting is not shown when switch 9 is open. Other indicating means such as flashing lights maybe used. Incorporated in a camera Fig.4 an aperture stop is connected to the variable resistance 5 by a pin 16 and brush 17 attached to a slider 15. Plate 18 supporting resistance 5 is slidably mounted within the camera body and interlocks with the film sensitivity and shutter speed controls 20 and 19. |
