摘要 |
<p>Low frequency streaking noise which is effected by modulating the black reference with high frequency noise is eliminated from the displayed picture in a television system by switching the signal during the horizontal blanking interval to a noise-free black reference. A CCD or other imagers where a pixel-by-pixel reference is available provide a unique opportunity to eliminate low frequency streaking in the video display. Each pixel of a solid state imager includes a black level reference. In accordance with the invention, a switch circuit is added to a correlated double sampling system used in conjunction with a CCD imager. During the horizontal blanking interval the switch is rendered conductive to substitute a noise-free reference derived from the pixel clamp.</p> |