摘要 |
Control apparatus for controlling the quantity of light includes a light emitting device for emitting light in response to a driving signal applied thereto, a photodetector for receiving the light to produce a detection signal representative of the quantity of the light received, a comparator for comparing the detection signal with a reference signal, a circuit for applying a recording signal to the light emitting device, a start control responsive to an instruction signal which causes the control apparatus to start controlling the quantity of light during the time period when no recording signal is applied, an incrementing device for incrementing the driving signal to be applied to the light emitting device in response to the instruction signal received, and a stopping circuit for stopping the incrementing in response to the comparator to hold a count which is contained in the incrementing device when stopping, until the instruction signal is subsequently applied. The light emitting device may include an array of light emitting elements.
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