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Full-Text Articles in Physics
Dark Current Measurements In A Cmos Imager, William C. Porter, Bradley Kopp, Justin Charles Dunlap, Ralf Widenhorn, Erik Bodegom
Dark Current Measurements In A Cmos Imager, William C. Porter, Bradley Kopp, Justin Charles Dunlap, Ralf Widenhorn, Erik Bodegom
Physics Faculty Publications and Presentations
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 …
Measurements Of Dark Current In A Ccd Imager During Light Exposures, Ralf Widenhorn, Ines Hartwig, Justin Charles Dunlap, Erik Bodegom
Measurements Of Dark Current In A Ccd Imager During Light Exposures, Ralf Widenhorn, Ines Hartwig, Justin Charles Dunlap, Erik Bodegom
Physics Faculty Publications and Presentations
Thermal excitation of electrons is a major source of noise in Charge-Coupled Device (CCD) imagers. Those electrons are generated even in the absence of light, hence the name dark current. Dark current is particularly important for long exposure times and elevated temperatures. The standard procedure to correct for dark current is to take several pictures under the same condition as the real image, except with the shutter closed. The resulting dark frame is later subtracted from the exposed image. We address the question of whether the dark current produced in an image taken with a closed shutter is identical to …