Abstract:
A method includes generating an intensity value based on illumination received at a pixel of an imaging system. The intensity value is generated by integrating values using a first counter of a detector during a first period of time. The method also includes integrating the values repeatedly during smaller second periods of time within the first period of time using a second counter of the detector. The second counter has a lower bit resolution than the first counter. The method further includes resetting the second counter for each of the second periods of time. In addition, the method includes generating a pixel event indicator in response to the second counter outputting a specified value. The method may also include determining whether one or more neighboring detectors also generated one or more pixel event indicators and generating an event indicator when the one or more neighboring detectors also generated the one or more pixel event indicators.
Abstract:
A focal plane array having: an imaging array section, comprising: an array of electromagnetic radiation detectors; and an address section providing outputs from selectively enabled detectors. The imaging array section comprises a plurality of circuit blocks, each one of the circuit blocks having a primary circuit and a redundant circuit. Test circuitry is for provided for supplying test signals to test each one of the primary circuits and determining whether a response from the test signals is proper or improper and for storing in the test circuitry in response to such determining select signals associated with each one of the tested circuit blocks. An array controller is provided for, during a subsequent normal operating mode, providing timing pulses to the address section wherein the address section selectively enables the detectors using either the primary or redundant circuits in the plurality of circuit blocks selectively in accordance with the stored select signals.
Abstract:
A focal plane array having: a plurality of detectors; a plurality of unit cell sections, each section being fed by charge produced by corresponding detector for producing a sequence of frames; and a plurality of sets of storage sections, each section being coupled to a corresponding one of the unit cells. Each set of storage sections includes a plurality of storage units for sequentially storing the frames. A region of interest selector section examines the frames of the plurality of unit calls, to detect at least one of the frames having a predetermined characteristic. A processor: (i) identifies a sub-set of the plurality of unit cells proximate the detected unit cells having the predetermined characteristic to establish a region of interest; and (ii) sequentially reads the plurality of storage units in the storage sections coupled to the sub-set of unit cells in the established region of interest.
Abstract:
A configurable driver is presented, comprising: a first transistor of a first type coupled to a first node; a second transistor of the first type coupled to a second node; a first transistor of a second type coupled to the first node; a second transistor of a second type coupled to the second node; a first multiplexer coupled to a gate of the first transistor of the first type; a second multiplexer coupled to a gate of the second transistor of the first type; a third multiplexer coupled to a gate of the first transistor of the second type; a fourth multiplexer coupled to a gate of the second transistor of the second type; and one or more switching devices coupled between the first node and the second node.
Abstract:
An apparatus includes a memory having memory elements configured to store bits of a count value. The apparatus also includes sense amplifiers configured to read the bits of the count value from the memory elements and write amplifiers configured to write the bits of the count value to the memory elements. The apparatus further includes at least one logic gate configured to generate at least one feedback bit based on the count value stored in the memory elements. Some of the sense amplifiers are coupled to some of the write amplifiers in order to read and shift a subset of the bits of the count value and store the shifted subset of the bits of the count value in the memory. The shifted subset of the bits of the count value and the at least one feedback bit form an updated count value in the memory elements.
Abstract:
An analog counter circuit for use with a digital pixel includes: an input; an output; a first stage electrically coupled to the input that is charged to an initial charge voltage; a second stage that includes an accumulating charge storage device; and a charge transfer device between the first and second stages that includes a transfer voltage. The charge transfer device allows charge from the first stage to pass to the second stage and be accumulated on the accumulating charge storage device as long as a voltage at a node in the first stage is greater than the transfer voltage.
Abstract:
A TDI scanner including a dynamically programmable focal plane array including a two-dimensional array of detectors arranged in a plurality of columns and a plurality of rows, the array being divided into a plurality of banks separated from one another by gap regions, each bank including a plurality of sub-banks, and each sub-bank including at least one row of detectors, a ROIC coupled to the focal plane array and configured to combine in a TDI process outputs from detectors in each column of detectors in each sub-bank, and a controller configured to program the focal plane array to selectively and dynamically set characteristics of the focal plane array, the characteristics including a size and a location within the two-dimensional array of each of the plurality of sub-banks and the gap regions, the size corresponding to a number of rows of detectors included in the respective sub-bank or gap region.
Abstract:
A method includes generating an intensity value based on illumination received at a pixel of an imaging system. The intensity value is generated by integrating values using a first counter of a detector during a first period of time. The method also includes integrating the values repeatedly during smaller second periods of time within the first period of time using a second counter of the detector. The second counter has a lower bit resolution than the first counter. The method further includes resetting the second counter for each of the second periods of time. In addition, the method includes generating a pixel event indicator in response to the second counter outputting a specified value. The method may also include determining whether one or more neighboring detectors also generated one or more pixel event indicators and generating an event indicator when the one or more neighboring detectors also generated the one or more pixel event indicators.
Abstract:
According to one aspect, embodiments herein provide a unit cell circuit comprising a photodetector configured to generate a photo-current in response to receiving light, a first integration capacitor configured to accumulate charge corresponding to the photo-current, a second integration capacitor configured to accumulate charge corresponding to the photo-current, a charge diverting switch coupled to the photodetector and configured to selectively couple the first integration capacitor to the second integration capacitor and divert the photo-current to the second integration capacitor in response to a voltage across the first integration capacitor exceeding a threshold level, and read-out circuitry coupled to the first integration capacitor and the charge diverting switch and configured to read-out a first voltage sample from the first integration capacitor corresponding to charge accumulated on the first integration capacitor and to read-out a second voltage sample from the second integration capacitor corresponding to charge accumulated on the second integration capacitor.
Abstract:
A combined scanning and staring (SCARING) focal plane array (FPA) imaging system having a plurality of modes of operation is provided. In one example, the SCARING FPA system includes a photodetector array with a plurality of photodetectors arranged in a plurality of photodetector rows, a readout integrated circuit (ROIC) coupled to the photodetector array, and a processor coupled to the ROIC. The processor coupled to the ROIC is configured to dynamically configure the SCARING FPA between a scanning mode of operation and a staring mode of operation.