Abstract: A scintillator for positron emission tomography is provided. The scintillator includes a garnet compound of a formula of A3B2C3O12 and an activator ion consisting of cerium. A3 is A2X. X consists of at least one lanthanide element. A2 is selected from the group consisting of (i), (ii), (iii), and any combination thereof, wherein (i) consists of at least one lanthanide element, (ii) consists of at least one group I element selected from the group consisting of Na and K, and (iii) consists of at least one group II element selected from the group consisting of Ca, Sr, and Ba. B2 consists of Sn, Ti, Hf, Zr, and any combination thereof. C3 consists of Al, Ga, Li, and any combination thereof. The garnet compound is doped with the activator ion.

Abstract: A scintillator for positron emission tomography is provided. The scintillator includes a garnet compound of a formula of A3B2C3O12 and an activator ion consisting of cerium. A3 is A2X. X consists of at least one lanthanide element. A2 is selected from the group consisting of (i), (ii), (iii), and any combination thereof, wherein (i) consists of at least one lanthanide element, (ii) consists of at least one group I element selected from the group consisting of Na and K, and (iii) consists of at least one group II element selected from the group consisting of Ca, Sr, and Ba. B2 consists of Sn, Ti, Hf, Zr, and any combination thereof. C3 consists of Al, Ga, Li, and any combination thereof. The garnet compound is doped with the activator ion.

Abstract: A method and an apparatus for detecting photons are disclosed. The apparatus includes a scintillator single crystal and an avalanche photodiode coupled to the scintillator single crystal. The scintillator single crystal is at a temperature greater than about 175° C. and at a shock level in a range from about 20 Grms to about 30 Grms. The scintillator single crystal includes a praseodymium doped composition selected from (LaxY1-x)2Si2O7:Pr, ABCl3-yXy:Pr, A2(Li,Na)LaCl6-yXy:Pr, or any combinations thereof. As used herein A is cesium, rubidium, potassium, sodium, or a combination thereof, B is calcium, barium, strontium, magnesium, cadmium, zinc, or a combination thereof, and X is bromine, iodine, or a combination thereof. Further, (0<x<1), and (0<y<3).

Abstract: A silicon photomultiplier array including a plurality of microcells arranged in rows and columns. A plurality of circuit traces connecting microcell output ports to the array pixel output port, with one or more impedance matching networks connected to at least one of the circuit traces. The impedance matching networks can be connected between each row circuit trace and the pixel output port. Impedance matching networks can be located between junctions of adjacent microcell output ports and row circuit traces.

Abstract: A method for determining depth-of-interaction correction in a PET system. The method includes modifying crystal and readout configuration to improve depth-dependent arrival profile of scintillation photons, creating a photon dispersion model within a scintillator crystal, measuring photon arrival profile of individual gamma ray event, deriving an estimated depth-of-interaction, and deriving a gamma ray event time based on a time stamp corrected with the estimated depth-of-interaction. The method further includes modeling dispersion at different depths of interaction within the scintillator crystal, providing a reflector layer to delay back-reflected photons, providing two respective readouts for the same gamma ray event from two respective pixels optically coupled by a backside reflector or modified crystal configuration, calculating a time difference of the photon arrival at the two pixels, and estimating the depth-of-interaction by applying a statistical weighting.

Abstract: A solid state photomultiplier includes at least one microcell configured to generate an initial analog signal when exposed to optical photons. The solid state photomultiplier further includes a quench circuit electrically coupled with the at least one microcell. The quench circuit includes at least one quench resistor configured to exhibit a substantially constant temperature coefficient of resistance over a selected temperature range.

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 silicon photomultiplier includes a plurality of microcells providing a pulse output in response to an incident radiation, each microcell including circuitry configured to enable and disable the pulse output. Each microcell includes a cell disable switch. The control logic circuit controls the cell disable switch and a self-test circuit. A microcell's pulse output is disabled when the cell disable switch is in a first state. A method for self-test calibration of microcells includes providing a test enable signal to the microcells, integrating dark current for a predetermined time period, comparing the integrated dark current to a predetermined threshold level, and providing a signal if above the predetermined threshold level.

Abstract: Embodiments of a solid state photomultiplier are provided herein. In some embodiments, a solid state photomultiplier may include a plurality of pixels, wherein each pixel of the plurality of pixels comprises a plurality of subpixels; and a first set of buffer amplifiers, wherein each buffer amplifier of the first set of buffer amplifiers is respectively coupled to a subpixel of the plurality of subpixels.

Abstract: A silicon photomultiplier array includes a plurality of microcells within the photomultiplier array and located on the silicon wafer, the plurality of microcells arranged in rows and columns, each of the plurality of microcells including an output port, and configured to provide a pulse waveform having pulse characteristics, at least one repatterning dielectric layer in contact with a silicon wafer layer back surface, the silicon wafer having an active surface opposed to the back surface, and a plurality of respective through-silicon-vias (TSVs) coupling the output port of respective ones of the plurality of microcells on the active surface of the silicon wafer to a plurality of respective circuit traces on the at least one repatterning dielectric layer disposed on the back surface of the silicon wafer. A method for producing the silicon photomultiplier array is also disclosed.

Abstract: A detector assembly for use in detecting radiation includes a scintillator and a solid state photomultiplier coupled to the scintillator. The detector assembly may include a light guide connected between the scintillator and the solid state photomultiplier. The detector assembly may be used within a receiver in a logging instrument for use downhole. The receiver is configured to detect radiation produced by an emitter or from naturally occurring sources.

Abstract: A method for determining depth-of-interaction correction in a PET system includes modifying crystal and readout configuration to improve depth-dependent arrival profile of scintillation photons, creating a photon dispersion model within a scintillator crystal, measuring photon arrival profile of individual gamma ray event, deriving an estimated depth-of-interaction, and deriving a gamma ray event time based on a time stamp corrected with the estimated depth-of-interaction. The method can include modeling dispersion at different depths of interaction within the scintillator crystal; providing a reflector layer to delay back-reflected photons; providing two respective readouts for the same gamma ray event from two respective pixels optically coupled by a backside reflector or modified crystal configuration, calculating a time difference of the photon arrival at the two pixels, and estimating the depth-of-interaction by applying a statistical weighting.

Abstract: A system and method for compensating signal delay across a solid state photomultiplier. The method including determining respective arrival times of signals from a plurality of microcells of the photomultiplier, calculating a signal transit time delay difference between the respective arrival times for individual signals, correlating the individual transit time delay differences to an amount of respective signal propagation compensation for respective microcells of the photomultiplier, and introducing the respective signal propagation compensation into circuitry of the respective microcells. The method also includes at least one of adjusting a response shape of a photodiode within each of the plurality of microcells, adjusting operating parameters of a one-shot pulse circuit within the microcells, and modifying circuit design values of each microcells during fabrication of the photomultiplier.

Abstract: A photon detector having an optical transparent plate and photodiode array interconnected by an optical light guide array. The optical light guide array including elements providing a transmission line between the optical transparent plate and the photodiode array, where the position of one or more optical light guide elements is formed to adjust for a miss-registered photodiode individual element.

Abstract: Embodiments of a solid state photomultiplier are provided herein. In some embodiments, a solid state photomultiplier may include an epitaxial layer, a high voltage region formed in the epitaxial layer, a low voltage region formed in the epitaxial layer, and an intermediate region disposed between the high voltage region and low voltage region, wherein the high voltage region is electrically coupled to the low voltage region via the intermediate region, and wherein at least a portion of the epitaxial layer is disposed between the high voltage region and intermediate region and between the low voltage region and the intermediate region.

Abstract: A silicon photomultiplier array including a plurality of microcells arranged in subgroupings, each microcell of a respective subgrouping providing a pulse output in response to an incident radiation. Each microcell output interconnected by respective traces of equal length to either a summing node or an integrated buffer amplifier. Each respective summing node configured to sum the pulse outputs of a first subgroup of the microcell subgroupings, and each respective integrated buffer amplifier configured to sum the pulse outputs of each microcell of a second subgrouping, the respective integrated buffer amplifier located on the silicon photomultiplier array within the second subgroup of microcells. The plurality of microcells arranged in one of columns and rows, and a first group of the arranged plurality of microcells being a mirror image of a second group of the arranged plurality of microcells about a midpoint between one of the columns and rows.

Abstract: A silicon photomultiplier array including a plurality of microcells arranged in rows and columns. A plurality of circuit traces connecting microcell output ports to the array pixel output port, with one or more impedance matching networks connected to at least one of the circuit traces. The impedance matching networks can be connected between each row circuit trace and the pixel output port. Impedance matching networks can be located between junctions of adjacent microcell output ports and row circuit traces.

Abstract: A solid state photomultiplier includes at least one microcell configured to generate an initial analog signal when exposed to optical photons. The solid state photomultiplier further includes a quench circuit electrically coupled with the at least one microcell. The quench circuit includes at least one quench resistor configured to exhibit a substantially constant temperature coefficient of resistance over a selected temperature range.

Abstract: A scintillator block is presented. The scintillator block includes at least one scintillator having an isotropic volume. Furthermore, the scintillator block includes a laser-generated three-dimensional pattern positioned within the isotropic volume of the at least one scintillator, where the laser-generated three-dimensional pattern is configured to modify one or more optical properties within the isotropic volume of the at least one scintillator, and where the three-dimensional pattern varies along one or more of a depth, a width, and an angular orientation of the at least one scintillator.

Abstract: A method and an apparatus for detecting photons are disclosed. The apparatus includes a scintillator single crystal and an avalanche photodiode coupled to the scintillator single crystal. The scintillator single crystal is at a temperature greater than about 175° C. and at a shock level in a range from about 20 Grms to about 30 Grms. The scintillator single crystal includes a praseodymium doped composition selected from (LaxY1-x)2Si2O7:Pr, ABCl3-yXy:Pr, A2(Li, Na)LaCl6-yXy:Pr, or any combinations thereof. As used herein A is cesium, rubidium, potassium, sodium, or a combination thereof, B is calcium, barium, strontium, magnesium, cadmium, zinc, or a combination thereof, and X is bromine, iodine, or a combination thereof. Further, (0<x<1), and (0<y<3).