摘要 |
The apparent size of the image produced by a clocked solid-state television imager is controlled by the read clock rate. In a camera using such an imager the clock rate is adjusted to provide an effect similar to zoom. Where a plurality of imagers are used in a color camera, differential control of the clock rate as between the imagers allows compensation for lens chromatic aberration thereby providing for correction of misregistration. In the case where the optical system includes a variable focal length such as a zoom lens, the zoom control is coupled to the size clock control for compensating for the differences in optical power for different colors. The size adjustment may result in a second-order centering error. The centering error is reduced by a scheme for changing the time at which the read clock is gated to the imager in dependence upon the clock rate.
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