| 摘要 |
An electronic flash apparatus comprises a flash lamp and a semiconductor switching element which are connected in series across a main capacitor, and a flash control circuit which measures light reflected from an object to be photographed illuminated by flash light produced by the flash lamp, and produces a control signal to render the semiconductor switching element nonconductive. The flash control circuit includes a photoelectric converting circuit for converting the reflected light into a voltage signal, an integrator for integrating the voltage signal, and a comparator for comparing the output voltage from the integrator with a reference voltage. To obtain a proper flash exposure a compensation signal generating circuit is provided which is responsive to the initiation of flashing of the flash lamp to produce a compensation signal having a desired waveshape. The compensation signal acts on the flash control circuit to control the generation timing of the control signal. The flash light produced by the flash lamp after the switching element has been rendered nonconductive is positively used for a proper exposure.
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