| 摘要 |
PURPOSE:To permit arbitrary setting of a photometric range according to the brightness of a object by outputting only the photocurrent of the prescribed partial region of the object to an arithmetic means according to the preset reference signal. CONSTITUTION:The output signals from a photodetecting range of a photodetecting part 1 divided to nXm matrix are supplied successively to a switch 20 via an A/D converting circuit 18. The switch 20 is connected to a movable contact 20-b, and the output of the circuit 18 is supplied to an average value operating part 2, by which the average value of mXn pieces of photodetection values is calculated. This average value is supplied to an AND gate 42 via the addres 30, 32 and comparators 38, 40 of a decision part 3. The gate 42 supplies the signal of an H level to a gate circuit 46 if the output signal of the part 1 is within the range set by a photographer in reference signal generators 34, 36. The circuit 46 is electrically conducted by the output signal of the gate 42 to supply only the output signal of the part 1 which is decided to be within the photometric range by the part 3 to an exposure operating part 5. The part 5 calculates an exposure value by the output signal of the circuit 46. |
