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A Charge Integrator Amplifier and Trap Detector for pico-Joule Laser Pulse Energy Measurement



Malcolm G. White, David J. Livigni, Rodney W. Leonhardt, Geiland Porrovecchio, Marek Smid


We report the characterisation and calibration of a charge integrator amplifier, developed for pico-joule laser pulse energy measurement at repetition rates up to 1 kHz. The amplifier is designed to operate in conjunction with an input charge source, such as a silicon or InGaAs photodiode. The device outputs a 20-bit resolution digital signal, which is converted to pulse energy through post processing, by knowing the absolute responsivity of the detector and the calibration factors of the charge amplifier. The amplifier and silicon trap detector was compared with the low-level laser pulse energy scale maintained by NIST, Boulder and showed agreement at a level better than 1 %. Further, the amplifier was calibrated at CMI and NIST one year apart - the calibration agreed to within 0.2 %.


White, M. , Livigni, D. , Leonhardt, R. , Porrovecchio, G. and Smid, M. (2018), A Charge Integrator Amplifier and Trap Detector for pico-Joule Laser Pulse Energy Measurement, Metrologia, [online], (Accessed July 18, 2024)


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Created August 10, 2018, Updated January 28, 2019