Combined pulse and integration detection

2008 – US7564022

A method for time-gating the sensitivity of an imager structure having a plurality of photodiodes comprises applying an electric field over the photodiodes, the electric field having an amplitude and a polarity so as to reverse bias or slightly forward bias the photodiodes at a bias voltage below 0.5 Volts, and varying the photodiodes between high and low charge collection efficiency or sensitivity by changing the amplitude of the electric field over the photodiodes. A corresponding imager structure is also provided.

 

 

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Analog X-ray photon counting pixel

2009 – US8198577

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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