A new CCD architecture of high-resolution and sensitivity for color digital still picture

Abstract

A new charged-coupled device (CCD) architecture developed for building high-resolution and high-sensitivity image sensors suitable for color digital still picture applications is presented. The sensor is based on the interline CCD structure. Both the interline pixels and the vertical charge transfer lines are utilized as light-sensing elements to improve simultaneously the resolution and sensitivity. This device is named the sea-of-photosensor array (SPA-CCD). A camera and supporting digital system were designed and built specifically to evaluate the device. Digital picture processing for white balance adjustment, chromatic correction, and high-frequency luminance was performed to improve color reproduction and picture resolution. An increased light sensitivity and limiting resolutions of 550 horizontal lines and 400 vertical lines on a TV screen were confirmed with an SPA-CCD of the same chip size as a conventional 190-k pixel IT-CCD. The new design of the SPA-CCD overcomes both the sensitivity and the resolution limitations of previous approaches. >