Highly efficient photon counters precisely tested

Photon counters from Laser Components’ COUNT series achieve a typical quantum efficiency of 75%, confirmed with comparative measurements by the Physikalisch-Technische Bundesanstalt (PTB). At a wavelength of 670 nm, only a deviation of one percent from the specified value of 75% occurred.

To guarantee this precision to its customers, the manufacturer tests each module at 405 nm, 505 nm, 670 nm, and 804 nm for detection efficiency. Other performance parameters such as timing jitter, dark count rate, after pulsing, and dead time can also be determined. For this purpose, a new test station has been set up that is even more precisely tailored to the requirements of the COUNT modules.

The values determined using ultrashort-pulsed diode lasers and high-precision reference power meters are evaluated using a Time Tagger Ultra. This streaming time-to-digital converter has been specially developed by the cooperation partner Swabian Instruments for time-correlated single photon counting (TCSPC), time interval counting, and coincidence counting.

PTB is an institution of the German Federal Ministry of Economics and Climate Protection. As the national metrology institute, it is the top authority on all questions regarding correct and reliable measurement.