A method to increase DR using column-level automatic gain selection

IISW, May 31, 2017, Hiroshima

Gaozhan Cai, Wei Wang, Bert Luyssaert, Bart Dierickx, Gerlinde Ruttens, Bert Uwaerts, Dirk Uwaerts, Jente Basteleus, Jens De Vroe, Walter Verbruggen, Peng Gao, Donal Denvir , Philip Steen

In this paper we present an image sensor with a very high linear dynamic range that is obtained by combining a pixel with using three level transfer gate method and a column-level automatic gain selection. The automatic gain selection (AGS) picks one out of three linear ranges each having a largely different conversion gain. The data rate remains the same as without high dynamic range, thus preserving the maximal frame rate. Scientific CMOS (sCMOS)[1] uses dual column level amplifiers with different gains, dual ADCs and combine dual output data afterwards. In contrast here, we implemented the AGS function within the column readout circuitry, selecting one out of the three different conversion gains. The different conversion gains are realized in the pixel (large QFW and small QFW), and in the column amplifier having a gains 8x and 1x.


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How to hand-calculate MTF in front-side and backside illuminated image sensors

IISW, May 30, 2017, Hiroshima

Bart Dierickx, Jean Bourgain, Bert Luyssaert

A pixel for the detection of electromagnetic radiation or impinging high energy particles, in particular for detecting X-ray photons, including a radiation or impinging high energy particles into a radiation signal, a converter for converting the radiation signal into a pulse train, and an analog accumulator for accumulating the pulses of a pulse train to an analog signal for readout. The analog accumulator is adapted such that the analog signal is non-linearly proportional to the pulse count. Such non-linear analog accumulator has the advantage of an large dynamic range.



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