| 摘要 |
PURPOSE:To select optionally the magnification by quantizing a peak-hold signal from an output of an image sensor, sampling the signal in an optional sampling frequency and obtaining a picture signal. CONSTITUTION:A quantized signal from a CCD 1 is applied to a peak-hold circuit 2, where the peak value is held. A peak hold pulse signal is applied to comparators C1-C3. A value of an input signal to the comparators C1-C3 is compared respectively with a reference value, a signal of logical ''1'' is generated when the signal is larger than the reference value and a value of logical ''0'' is generated when smaller than the reference value. These logical outputs are latched with a clock shifted by a prescribed time from a generation time of the pulse signal at a delay circuit 8 and a latch circuit 6. Each output of the circuit 6 is sampled in a sampling frequency in response to a desired magnification by the sampling circuit 9 and a digital display picture output signal with a desired magnification is obtained. |
