A 1/2-inch 380 kpixel progressive-scan CCD image sensor has been developed. It has a 3-phase 3-level electrode V-CCD, a dual H-CCD with a compound channel, and dual-channel output circuitry. The newly developed H-CCD has a wide dynamic range and a high efficiency of transfer between horizontal shift registers. When this H-CCD is driven by 4 0 Vp-p horizontal drive pulse, it can transfer electron packets equivalent to 1150 mV. All the image signals can be read out without mixing every 1/60 s and this image sensor provides a vertical resolution of 480 TV lines. This device is suitable for image-processing, image-recognition, and image-capturing.

View full abstract

To reduce the size and cost of a consumer-use solid-state high-definition camera, a new image-sensing technology with a pixel reduction method has been studied by simulation. This simulation confirmed that a resolution of more then 700 TV lines can be obtained for horizontal and vertical directions. This high resolution is due to a newly developed color signal-processing algorithm that eliminates the aliasing caused by the use of three 0.43-Mpixel sensors : two sensors to pick up signal G with a pixel-offset arrangement and one sensor to pick up signals B and R with an interleaving arrangement.

View full abstract

Because a charge injection type “two level” CCD image sensor needs metal contact to carry signal charge from its photoelectrical conversion layer to its storage diode, this type of sensor has a peculiar random noise generated in its picture cells. This noise has been studied from the view-point of electron emission from the storage diode, and the noise value obtained by measuring a 1-inch 2-million pixel image sensor corresponds to the analytically derived noise. We expect that the smaller a picture cell is, the less the noise value is.

View full abstract

The proposed structure allows opaque driving electrode to be removed from the cell surface, increasing high quantum efficiency and resulting in higher photo-sensitivity. Mode selection (such as reset, charge storage and readout) can be performed by driving electrodes buried in silicon substrate. Readout signal amplitude, which is the output of a source follower, is determined by the number of signal holes stored in each photodiode. Simulation of a device with 1000×1000 of these cells/cm² indicated that the sensor could be operated without image lag, blooming and low smear. The simulated photo-sensitivty, cell charge capacity and charge-to-voltage coversion factor were high enough for videocameras.

View full abstract

To improve the picture quality of the single-chip CCD color video cameras with line-sequential color difference systems, we suggest the new luminance signal process that uses the correlation of the ratio between chrominance signals and luminance signals in a localized picture area and lessens the attenuation of high-frequency signals. Conventional processing has proved effective in increasing the resolution only of black-and-white images, but our new process also enhances the resolution of colored images. We have used computer simulation to examine and verify the fundamental functions of our process and to optimize the filter coefficient etc. We have confirmed the improvement of resolution by using experimental hardware based on our simulation results.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract