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This paper presents a solid state image sensor intended for use in 625 lines color TV cameras. The "Line Transfer" organization allowed, using 3 p design rules over a 6,6 x 8,8 mm format, the realization of an imager whose main performances are . 576 lines by 462 pel, minimum Scene illumination : 30 lux and good protection against smearing and bloomingThe line transfer organization uses conductive buses to transfer photoelectric information in the vertical direction. The interesting feature of this organization is its ability to separate the signal charges from the spurious ones through a double reading of the bus voltage. The principle of operation and specific performances are first described and expressed in terms of vertical transfer inefficiency. The mechanism of transfer inefficiency is analyzed. Its application to the bus's reading of a line transfer imager is detailed and the main performances are deduced.

A SINGLE-CHIP image sensor for color cameras can be achieved by using different arrangements: e.g., CCDs in frame transfer or interline, or MOS XY addressing. Each type has well known merits and demerits. Another structure, which employs a MOStype photosensor and a CTD-type readout shift register, has been proposed"2. Each row of pixels is selected line after line by a vertical MOS shift register and transferred via vertical buses to a readout CCD. The line transfer offers many advantages, but has drawbacks concerning either a loss of resolution at low light levels or a too large noise.intended for 625-line single-chip color TV cameras, with an imaging area corresponding to that of a 2/3" vidicon

CCD's have become serious competitors to camera tubes, even for HDTV. The challenge set by HDTV requirements implies to soive the sensitivity I resolution antinomy with presently available VLSI technologies. This paper presents the various designs used by CCD's manufacturers and details the main performances of the two devices realized. These performances are related to the various technological choices and compared to physical limits.