A Wide-Dynamic-Range Compression Image Sensor With Negative-Feedback Resetting

Author

Ikebe, Masayuki ; Saito, Keita

Author_Institution

Graduate Sch. of Inf. Sci. & Technol., Hokkaido Univ., Sapporo-Shi

Volume

7

Issue

5

fYear

2007

fDate

5/1/2007 12:00:00 AM

Firstpage

897

Lastpage

904

Abstract

A CMOS image sensor capable of wide-dynamic-range compression is proposed. This sensor has two main features. It uses a negative-feedback technique to set any intermediate voltage into photodiode (PD) capacitance in the pixel circuit. It also uses a quasi-holding function by resetting the pixel-output voltage into PD capacitance. Dynamic range compression is achieved by individually selecting pixels and by setting an intermediate voltage or performing quasi-holding with respect to each pixel. Output data has a polygon-like form corresponding to a change from high sensitivity to low sensitivity as optical intensity becomes stronger. Experimental results obtained with a chip fabricated using a 0.25-mum CMOS process demonstrate dynamic range compression

Keywords

CMOS image sensors; capacitance; feedback; photodiodes; 0.25 micron; CMOS image sensor; individual reset; negative-feedback resetting; optical intensity; photodiode capacitance; pixel circuit; quasiholding function; wide-dynamic-range compression; CMOS image sensors; Capacitance; Circuits; Dynamic range; Image coding; Image sensors; Optical sensors; Photodiodes; Sensor phenomena and characterization; Voltage; CMOS image sensor; dynamic range compression; individual reset; negative-feedback reset;

fLanguage

English

Journal_Title

Sensors Journal, IEEE

Publisher

ieee

ISSN

1530-437X

Type

jour

DOI

10.1109/JSEN.2007.894897

Filename

4154674