Abstract: A method for detecting an active pixel in a sensor having a plurality of addressable pixels, comprising detecting a trigger event that causes a pixel to go active and setting a corresponding resettable latch from an initial unset logic state to a set logic state and establishing a time window during which another pixel which becomes active is assumed to originate from the same trigger event. For all pixels that become active within the time window a corresponding analog value of the pixel is sampled and held in response to a logic signal indicative of another pixel currently being active, and an incident time of the pixel going active is established. Each of the latches in the segment is sparsely read so as successively to identify latches which are in the set logic state each corresponding to an active pixel having a known address in the sensor segment. The known address of each active pixel is associated with the incident time of the pixel going active and the respective sampled and held analog value.

Abstract: The present invention relates to a method and apparatus for simultaneous quantification of the amounts of one or more radioactive nuclides within arbitrary regions on a surface where these nuclides have been deposited, adsorbed or fixed. These radioactive nuclides serve as markers on compounds that typically have been incorporated into tissue sections or into larger biological molecules that by various mechanisms have been bound to chemical substances on this surface. The method is especially well suited for DNA microarray deductions through the use of nucleotides labelled with different beta-emitting radionuclides.

Abstract: A method and threshold discrimination circuit for threshold discriminating an accumulated charge signal in a charge readout sensor, wherein the accumulated charge signal is shaped with a filter prior to effecting threshold discrimination thereof, and a slew rate of the filter is limited so that the filtered accumulated charge signal reaches a predetermined threshold at a time that remains constant irrespective both of an amplitude of the signal and of charge collection time. Such a threshold discrimination circuit finds particular application in a charge readout sensor in a nuclear imaging system where very accurate determination of the time of photon emission is required.

Abstract: A method for reading a data signal emitted by an active pixel in a sensor having a plurality of addressable pixels, comprising the steps of (a) grouping the plurality of pixels into at least two groups each having a fraction of the plurality of addressable pixels, (b) identifying an active group of addressable pixels in which the active pixel is located, (c) providing a reading circuit for the active group of addressable pixels, and (d) reading a magnitude of the data signal in respect of each pixel in the active group of addressable pixels so as to identify the active pixel. A system uses such a method for reading a data signal emitted by an active pixel in a sensor module having a plurality of addressable pixels arranged into at least two groups, and comprises an identifying circuit commonly coupled to each group of pixels and responsive to the data signal for identifying an active group containing the active pixel without identifying the active pixel itself.