| 摘要 |
PURPOSE:To make a circuit operate in a simple and stable manner by a constitution wherein a pulse generating device is controlled by the output of a comparing device whose input is obtained from the output of a delay device connected to the output of a photoelectric photometrical device and from the output of the photoelectric photometrical device. CONSTITUTION:A switch S1' is turned on in linkage to a switch S. The output P of a photometrical circuit Ph is transduced into a signal P' through a connector Cn and the latter is inputted in a comparator A4 through an amplifier A1, a delay circuit D, switch contacts (a) and (b) and an operational amplifier A3. In the case of a camera, for instance, a contacting piece is connected to the side of (a) and (b) when the light intensity of an object changes from strong to weak, while it is connected to the side of (c) and (d) when the change is contrary. The comparator A4 compares the input with the prescribed voltage VR, and when the input is larger than the voltage, it turns inverse and makes a controlling device Co operate for exposure through the intermediary of one-shot multiplier OM, TR1 and TR2. When the piece is switched on the side of (c) and (d), the exposure is performed without being delayed. By this constitution, the stable operation can be performed with the simple structure. |
