Title :
Analysis of photoelectric conversion characteristics under knee control operation for CCD imagers
Author :
Nakamura, Nobuo ; Matsunaga, Yoshiyuki ; Egawa, Yoshitaka ; Endo, Yukio ; Tango, Hiroyuki ; Yoshida, Okio
Author_Institution :
Res. & Dev. Center, Toshiba Corp., Kawasaki, Japan
fDate :
12/1/1994 12:00:00 AM
Abstract :
A high-light signal suppression operation, knee control operation, was evaluated in order to apply to a STACK-CCD of 2/3-in 2 M-pixel high definition television (HDTV) imager overlaid with an amorphous silicon photoconversion layer. A smooth bend was observed in the measured photoconversion characteristics near a knee point. It was analyzed theoretically by applying a subthreshold current of the MOSFET in weak inversion for skimming excess charges and reading out signal charges through a field shift gate. The calculated curve showed good agreement with the measured curve. Effectiveness of the knee control operation using the field shift gate was shown experimentally and theoretically over that using a conventional vertical overflow drain for IT-CCD imagers
Keywords :
CCD image sensors; high definition television; television cameras; 2 Mpixel; CCD imagers; MOSFET; STACK-CCD; excess charges; field shift gate; high definition television; high-light signal suppression operation; knee control operation; photoelectric conversion characteristics; subthreshold current; weak inversion; Amorphous silicon; Blanking; Charge coupled devices; Charge-coupled image sensors; Dynamic range; HDTV; Image analysis; Image converters; Knee; Layout;
Journal_Title :
Electron Devices, IEEE Transactions on
