High dynamic-range CMOS image sensor cell based on self-adaptive photosensing operation

Author

Lee, Sungsik ; Yang, Kyounghoon

Author_Institution

Div. of Electr. Eng., Korea Adv. Inst. of Sci. & Technol., Daejeon

Volume

53

Issue

7

fYear

2006

fDate

7/1/2006 12:00:00 AM

Firstpage

1733

Lastpage

1735

Abstract

This brief presents the performance characteristics of a new CMOS active pixel structure based on a self-adaptive light-sensing operation, which is implemented using a standard 0.35-mum CMOS logic process. In order to improve the dynamic range (DR) as well as the sensitivity at low illumination intensity, a new photogate structure is proposed and incorporated into the pixel structure. At an optimum bias condition of the photogate, the DR was increased by more than three times and the sensitivity at low illumination intensity was improved by two times compared to the conventional structure. The new pixel structure is found to allow simultaneous improvements in both the DR and the sensitivity without any process modification

Keywords

CMOS image sensors; optical sensors; 0.35 micron; CMOS active pixel structure; CMOS image sensor cell; CMOS logic process; dynamic range; illumination intensity; optimum bias condition; photogate structure; self-adaptive light-sensing operation; self-adaptive photosensing operation; CMOS image sensors; CMOS logic circuits; CMOS process; Capacitance; Digital cameras; Dynamic range; Lighting; Mobile handsets; Photodiodes; Voltage; Adaptive sensitivity; CMOS active pixel sensor (CAPS); dynamic range (DR); photogate;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/TED.2006.875805

Filename

1643509