HDTV camera using digital contour
忠 杉木, Akria Nakao, Tomoyuki Uchida · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1992
The authers have developed the HSC-100 solid-state High-Definition TV(Camera. The canra promises a 6dB S/N and +6dB sensilivity far superior to conventional IIDTV cameras due to an imaging device construction. It also improves picture quality throughusing a digital contour unit. To satisfy IiDTV (SMPTE 240M) requirements a photo-conductive layered semiconductor imaging device (PSID) with 2 pixels has been developed. An amorphous silicon (a-Si) layeris added to the CCD scanner in this device. The a-Si layer carries out photoelectric conversion then interline transfer CCD reads out the photo induced electric charges. This configuraon provides a pixel aperture ratio of 100 thereby improving sensitivity comparedwith existing models. The layer structure also permits a wide dynamic range. A digital contour unit was developed to improve contour corrector characteristics. S/N and frequency response are improved by introducing digital signal processing. The 56dB S/N value is achieved with an 8 bit A/D converter. This S/N is about 10 dB better than that for conventional ultra-sonic delay lines. In addilion digital processing improves frequency response and delay time stability. A more natural contour correction characteristic has been attained with a contour correction signal derived from the luminance signal. 1.