| 摘要 |
PURPOSE:To enable the operation of a photometric value proper to a main object, by discriminating the size of the main object to select a photometric value operation formula and calculating the brightness information of the outermost side area of the object. CONSTITUTION:Silicon photodiodes SPD 8-13 generates photocurrents corresponding to the brightnesses which correspond to the areas 2A-2C4 on a light receiving part 6 and said photocurrents are sent out through logarithmic compression circuits 14-19. The output voltages of the circuits 16-19 are supplied to a peripheral brightness operation circuit 20 where the brightness value of the outermost peripheral part of an object is operated and, corresponding to the brightness state of the peripheral part, a predetermined number of values are averaged from the large value or smaller value of four values to be sent to a selection circuit 21 as an output value VC. The circuit 21 compares the value VC with the values from the circuits 14, 15 by selecting a plurality of operation formulae to send out output V2 for imparting proper exposure to the main object.
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