Abstract: Silicon photomultiplier and readout method A silicon photomultiplier device is provided which comprises a first electrode arranged to provide a bias voltage to the device, a second electrode arranged as a ground electrode for the device, and a third electrode arranged to provide an output signal from the device using the second electrode as the output signal ground.

Abstract: A method is provided of forming a light sensing arrangement for use in a light sensor. The method comprises tiling a plurality of individual light sensing elements on a carrier, each element having a notch formed in an edge thereof, the notch being adapted to provide space, when the elements are tiled together, for an electrical connection to be made between the carrier and a surface of the element arranged to faced away from the carrier. Each element may comprise Silicon Photomultiplier (SPM) circuitry.

Abstract: An apparatus for photon counting is disclosed that comprises a sensor element (5) comprising a photon detector (8) and a capacitance (2) for applying a potential difference across the detector (8). The apparatus also comprises switching circuitry (6) for connecting the sensor element (5) operatively to a voltage source (4) during a refresh period to charge the capacitance (2) to achieve a predetermined potential difference across the detector (8) above a threshold value, and for substantially isolating the sensor element (5) from the voltage source (4) during a sensing period in which the charged capacitance (2) maintains a potential difference across the detector (8) above the threshold value and in which the detection of a photon by the detector (8) causes at least some of the charge on the capacitance (2) to discharge through the detector (8). The apparatus also comprises control circuitry (12) for controlling the switching circuitry (6) to initiate refresh and sensing periods in alternating sequence.

Abstract: A method is provided of forming a light sensing arrangement for use in a light sensor. The method comprises tiling a plurality of individual light sensing elements on a carrier, each element having a notch formed in an edge thereof, the notch being adapted to provide space, when the elements are tiled together, for an electrical connection to be made between the carrier and a surface of the element arranged to faced away from the carrier. Each element may comprise Silicon Photomultiplier (SPM) circuitry.