Abstract: Photomultipliers are disclosed which comprise circuitry for detecting photo electric events and generating short digital pulses in response. In one embodiment, the photomultipliers comprise solid state photomultipliers having an array of microcells. The microcells, in one embodiment, in response to incident photons, generate a digital pulse signal having a duration of about 2 ns or less.

Abstract: A compensating current is applied at one or more points in a signal processing path to compensate for one or both of a dark or offset current present in an input signal. In certain implementations, the dark or offset current is present in a signal generated by a photomultiplier device. The dark or offset current may be monitored in an output of the signal processing path and, the monitoring being used to determine how much compensation is needed in the signal processing path and to allocate where in the signal processing path the compensation current will be applied.

Abstract: Exemplary embodiments are directed to shaping a readout pulse from a solid state photomultiplier (SSPM). A readout pulse can be received from the SSPM at an input of a buffer amplifier. The readout pulse can have a discharge portion with a discharge rate and a recharge portion with a recharge rate. A magnitude of the readout pulse increasing for the discharge portion and decreasing for the recharge portion. A frequency dependent input impedance circuit can be employed in electrical communication with the input of the buffer amplifier to shape the discharge portion of the readout pulse.

Abstract: Present embodiments relate to the calibration of detectors having one or more arrays of pixelated detectors. According to an embodiment, a method includes detecting optical outputs generated by a plurality of scintillation crystals of a detector with an array of pixelated detectors, generating, with the array of pixelated detectors, respective signals indicative of the optical outputs, generating, from the respective signals, a unique energy spectrum correlated to each of the plurality of scintillation crystals, grouping subsets of the plurality of scintillation crystals into macrocrystals, determining a representative energy spectrum peak for each macrocrystal based on the respective energy spectra of the scintillation crystals in the macrocrystal, comparing a value of the representative energy spectrum peak for each macrocrystal with a target peak value, and adjusting an operating parameter of at least one pixelated detector in the array of pixelated detectors as a result of the comparison.

Abstract: A multichannel application specific integrated circuit (ASIC) for interfacing with an array of photodetectors in a positron emission tomography (PET) imaging system includes a front end circuit configured to be coupled to the photodetectors and to receive discrete analog signals therefrom. The ASIC further includes a time discriminating circuit operably coupled to the front end circuit and configured to generate a hit signal based on a combination of the discrete analog signals, and an energy discriminating circuit operably coupled to the front end circuit and configured to generate a summed energy output signal based on each of the discrete analog signals and summed row and column output signals based on each of the discrete analog signals. The summed energy output signal represents an energy level of the detected radiation in the array of photodetectors, and the summed row and column output signals represent a location of the detected radiation.

Abstract: Exemplary embodiments are directed to characterizing a solid state photomultiplier (SSPM). The SSPM can be exposed to a light pulse that triggers a plurality of microcells of the SSPM and an output signal of the SSPM generated in response to the light pulse can be processed. The output signal of the SSPM can be proportional to a gain of the SSPM and a quantity of microcells in the SSPM and a value of an electrical parameter of the SSPM can be determined based on a relationship between the output signal of the SSPM and an over voltage applied to the SSPM.

Abstract: Exemplary embodiments are directed to shaping a readout pulse from a solid state photomultiplier (SSPM). A readout pulse can be received from the SSPM at an input of a buffer amplifier. The readout pulse can have a discharge portion with a discharge rate and a recharge portion with a recharge rate. A magnitude of the readout pulse increasing for the discharge portion and decreasing for the recharge portion. A frequency dependent input impedance circuit can be employed in electrical communication with the input of the buffer amplifier to shape the discharge portion of the readout pulse.

Abstract: Present embodiments relate to the calibration of detectors having one or more arrays of pixelated detectors. According to an embodiment, a method includes detecting optical outputs generated by a plurality of scintillation crystals of a detector with an array of pixelated detectors, generating, with the array of pixelated detectors, respective signals indicative of the optical outputs, generating, from the respective signals, a unique energy spectrum correlated to each of the plurality of scintillation crystals, grouping subsets of the plurality of scintillation crystals into macrocrystals, determining a representative energy spectrum peak for each macrocrystal based on the respective energy spectra of the scintillation crystals in the macrocrystal, comparing a value of the representative energy spectrum peak for each macrocrystal with a target peak value, and adjusting an operating parameter of at least one pixelated detector in the array of pixelated detectors as a result of the comparison.

Abstract: A method of light detection includes emitting a pulsed light beam from a pulsed light source; splitting the pulsed light beam with a beam splitting device into at least two light beam ray sets, wherein at least one of the ray sets collide with airborne particulates, resulting in backscattered light; which is received through an aperture(s); and detecting the received backscattered light at a detector. A light detection and ranging system is also disclosed. The present invention has been described in terms of specific embodiment(s), and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.

Abstract: A method of light detection includes emitting a pulsed light beam from a pulsed light source; splitting the pulsed light beam with a beam splitting device into at least two light beam ray sets, wherein at least one of the ray sets collide with airborne particulates, resulting in backscattered light; which is received through an aperture(s); and detecting the received backscattered light at a detector. A light detection and ranging system is also disclosed. The present invention has been described in terms of specific embodiment(s), and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.

Abstract: A wind anemometer comprises a light source for transmitting pulsed light signals, a receiver for receiving backscattered signals from airborne particles for each pulse of the transmitted pulsed light signals, a detector for detecting the received backscattered signals, and a processor to determine location of the airborne particles with respect to the anemometer based on the detected backscattered signals. The processor estimates wind velocity using changes in location of the airborne particles over at least one time interval.