Profile: AP Technologies Ltd. provides fibreoptic instruments, high power laser diodes, light emitting diodes, photodiodes, photon counting and silicon photo multipliers. We provide optical fibre fault locator device for detecting and characterising breaks & reflective faults in optical fibres. The silicon photomultiplier (SPM) is based on novel silicon structure optimised for low light sensing over a large area and is the ideal solution for OEMs striving to design portable, small & lower cost systems. The SPM incorporates a large parallel array of silicon photon-counting diodes (microcells) and integrated quenching elements to provide high gain and analogue readout. Incident photons are detected by individual microcells which avalanche and release a fixed quantity of charge onto the output node. The quenching element quenches the avalanche and resets the microcell ready for the next incident photon.