| 摘要 |
PURPOSE:To enable charging of only the electric charge required for optimum exposing into a power source capacitor by comparing the exposure detected from a light source for exposing and a preset reference value and controlling the input voltage to the power source capacitor by the control signal obtd. by such comparison. CONSTITUTION:If the signal from an exposure detector Ds is higher than a reference value, a control voltage increases and the current to be impressed to the high-frequency transformer 4 of an inverter circuit 3 is decreased and the secondary output of the high-frequency transformer decreases as well and therefore the charging voltage to a power source capacitor CL lowers. The charging voltage to the capacitor CL rises conversely when the signal from the detector Ds is lower than the reference value. The exposure is detected at every emission of a light source Xe for exposing and the charging voltage to the capacitor CL is so controlled that the quantity of light to be emitted next attains the optimum quantity and therefore the wasteful consumption of the energy charged in the capacitor CL is obviated. |
