Two Transistor Current Mode Active Pixel Sensor
Copyright 2007 IEEE. Published in the Proceedings of the IEEE International Symposium of Circuits and Systems (ISCAS), May 2007, pages 2846-2849.
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A novel current mode active pixel sensor for high resolution imaging is presented. The photo pixel is composed of a photodiode and two transistors: reset and transconductance amplifier transistor. The switch transistor is moved outside the pixel, allowing for lower pixel pitch and increased linearity of the output photocurrent. The increased linearity of the image sensor has greatly reduced spatial variations across the image after correlated double sampling and the column fix pattern noise is 0.35% of the saturated current. A discussion on theoretical temporal noise limitations of this design is also presented.
Viktor Gruev, Zheng Yang, Jan Van der Spiegel, and Ralph Etienne-Cummings. "Two Transistor Current Mode Active Pixel Sensor" Departmental Papers (ESE) (2007).
Available at: http://works.bepress.com/jan_vanderspiegel/3