CHELMSFORD, England, Sept. 20, 2010 — Laser Components UK Ltd.’s new Count single-photon counters achieve a quantum efficiency of >70% in the red region and, according to the company, a higher quantum efficiency in the blue spectral range than other modules on the market. They are suited for measurements across the wavelength range from 400 to 1000 nm. The devices are based on a purpose-developed silicon Geiger-mode avalanche photodiode and on quenching and signal-processing electronics from PicoQuant GmbH. Available in a compact housing, the photon counters can be easily integrated into user applications. Incoming photons generate corresponding electrical pulses that may be read out at the transistor-transistor logic output. The gating function allows the modules to be disabled between measurements to provide accidental overload protection. Standard modules are available with dark count rates ranging from 20 to 250 counts. Modules with <10 counts per second also are available. The modules are supplied with either an easy-to-use FC connection to the sample for multimode optical fibers that have a core diameter of up to 105 µm or in a free-beam version. Another option is a model optimized for timing resolution. Their compact housing and plug-and-play compatibility with photon counters currently available on the market facilitate replacement of those existing devices. Features include low dark count rates, an active area diameter of 100 µm, an operating temperature of 10 to 40 °C, a wide dynamic range and single 12-VDC supply operation. Applications include confocal microscopy, particle sizing, fluorescence analysis and lidar.