How does a Modulated Chlorophyll Fluorometer Measure Chlorophyll Fluorescence?
A modulated chlorophyll fluorometer uses sophisticated electronics to separate chlorophyll fluorescence from ambient light. The systems achieve this using a rapid pulsing excitation light in order to induce a corresponding pulsed fluorescence emission. The fluorometer uses a highly sensitive photodiode to detect and record the pulsed fluorescence signal and to ignore any non-pulsed signal. At physiological temperatures peak fluorescence emission occurs in the red region of the spectrum ( 685 nm) and extends into the infra-red region to around 800 nm (Krause and Weiss 1984) as shown in the diagram below.
