Three new Quantum EnergyMax sensors from Coherent enable accurate measurement of laser pulse energies down to 20pJ, as well as the average power of pulsed systems from the nanowatt to milliwatt level, across a broad range of wavelengths. Specifically, the J-10SI-LE and J-10SI-HE are both silicon photodiode-based sensors with apertures of 10mm and a spectral range of 325nm to 900nm, which measure down to 20pJ and 200pJ respectively, at repetition rates of up to 10kHz. The J-10GE-LE utilises a 10mm aperture germanium photodiode to measure minimum pulse energies of 200pJ over the 800-1700nm spectral range, also at up to 10kHz. The 10mm aperture is the largest currently available on the market for detectors of this sensitivity, and can often eliminate the requirement for an integrating sphere.
All three Quantum EnergyMax sensors are compatible with the Coherent LabMax-TOP meters. Quantitative measurement of picojoule pulses is notoriously difficult, but with these low noise meters and the new sensors’ built in wavelength compensation feature, an absolute accuracy of better than six per cent can be achieved. Quantum EnergyMax sensors also deliver a high repetition rate linearity of less than a one per cent error, from single pulse measurement to 10kHz.
Quantum EnergyMax sensors are useful for a broad range of research, commercial and military applications involving low power pulses. Examples include measurement of infrared pulsed lasers beyond 1064nm, typically used for military targeting purposes. Other examples are measurement of kHz ultrafast oscillators and regenerative amplifier systems with outputs at the microjoule level or lower.