Published In
Proc. SPIE 6816, Sensors, Cameras, and Systems for Industrial/Scientific Applications IX
Document Type
Article
Publication Date
2-1-2008
Subjects
Complementary metal oxide semiconductors, Image processing -- Digital techniques, CCD cameras -- Calibration
Abstract
We present data for the dark current of a commercially available CMOS image sensor for different gain settings and bias offsets over the temperature range of 295 to 340 K and exposure times of 0 to 500 ms. The analysis of hot pixels shows two different sources of dark current. One source results in hot pixels with high but constant count for exposure times smaller than the frame time. Other hot pixels exhibit a linear increase with exposure time. We discuss how these hot pixels can be used to calculate the dark current for all pixels. Finally, we show that for low bias settings with universally zero counts for the dark frame one still needs to correct for dark current. The correction of thermal noise can therefore result in dark frames with negative pixel values. We show how one can calculate dark frames with negative pixel count.
DOI
10.1117/12.769079
Persistent Identifier
http://archives.pdx.edu/ds/psu/9235
Citation Details
William C. Porter ; Bradley Kopp ; Justin C. Dunlap ; Ralf Widenhorn and Erik Bodegom, "Dark current measurements in a CMOS imager", Proc. SPIE 6816, Sensors, Cameras, and Systems for Industrial/Scientific Applications IX, 68160C (February 29, 2008); doi:10.1117/12.769079
Description
Copyright 2008 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.