Instrument: Fluorometer
A fluorometer or fluorimeter is a device used to measure parameters of fluorescence: its intensity and wavelength distribution of emission spectrum after excitation by a certain spectrum of light. The instrument is designed to measure the amount of stimulated electromagnetic radiation produced by pulses of electromagnetic radiation emitted into a water sample or in situ.
An underwater Pulse Amplitude Modulated fluorometer (diving-PAM, Walz, Germany) was used to measure the PSII photochemical efficiency.