Masayuki Hikiba

A 1/2-in CCD imager with lateral overflow-gate shutter

The design considerations and performance of an interline-transfer charge-coupled-device (IL-CCD) imager with a lateral overflow gate shutter are described. A 489(V)-pixel*670(H)-pixel 1/2-in IL-CCD imager is shown to have a variable shutter function, whose shutter speed is controlled successively from 1/60 to 1/15700 s by the timing of the overflow gate pulse. The device requires a low voltage of only 4 V and a simple overflow gate pulse to realize the shutter function without any undesirable die size enlargement. The key technology of the device is the self-aligned photodiode structure, which realizes a complete charge transfer. Combined with a microlens on the photodiode, the device can achieve high-definition or small-die-size imagers because of its high sensitivity. >

A 1/3-inch 410,000-pixel CCD Image Sensor With Feedback Field-plate Amplifier

The design considerations and performance of a 1/3-in format 410000-pixel interline transfer charge coupled device (CCD) (IL-CCD) image sensor are described. Some techniques have been introduced in order to shrink the pixel size to 6.4(H)*7.5(V) mu m without any deterioration in dynamic range and, signal-to-noise (S/N) ratio. The photodiode structure is designed to reduce the knee effect so as to avoid an overflow of the vertical CCD (V-CCD) register up to 500 times the saturating illumination. A depleted-well CCD structure is introduced to maintain the maximum charge-handling capability of 92000 electrons/packet in the V-CCD register, and high enough transfer efficiency of the horizontal CCD (H-CCD) registers with 5-V/sub p-p/ pulse driving. A feedback field-plate amplifier (FFPA) is introduced to raise the sensitivity of the output amplifier to 16.2 mu V/electron in order to obtain a large enough S/N ratio to the background noise of the peripheral circuits in a video camera. >

Lateral overflow-gate shutter for CCD image sensors

An analytical model of the lateral overflow-gate shutter operation In a CCD image sensor is reported and the validity of the model is confirmed by experiments. The optimized design was adopted In a 1 /2-inch 512(H)x489(V) CCD Image sensor so as to realize a shutter pulse of only 4Vpp. 1.