| 摘要 |
The range meter for a camera comprises an array of light-projectors IR1-IR5 which project irradiation beams towards subjects SB1, SB2 capable of being photographed and light-receiver PT which produces an output signal corresponding to the position or positions thereon at which reflected light is received. A Arithmetic device OP calculates the distance to a particular subject, and light-quantity control means EM controls the light-projectors IR1-IR5 so that the quantity of irradiation light produced by an outer light-projector of the array is less than that produced by an inner light-projector. The light projectors are preferably IR LEDs and the different light quantities may be produced by varying the number of magnitude of pulses fed to each projector. To save time, adjacent projectors may be powered by simultaneous, antiphase pulse trains. The array of light projectors is preferably a row, and the light-receiver may be a photodiode array. -
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