PEM200 User Manual
20
Functional Check
Figure 4.1 shows the basic electronic requirements. Most light sources will require an
electrical power supply, not discussed here. The detector is shown supplying a signal
to the oscilloscope, with the controller reference signal connected to the oscilloscope
trigger input.
Figure 4.2 Oscilloscope Waveform for PEM Set to 0.25 Wave Retardation Between Crossed Polarizers
and PEM 1f Reference Signal
The detector circuitry deserves some special comment. Care must be taken to ensure
adequate frequency response, typically several times the PEM operating frequency.
Pre-amplified photo detectors are available from Hinds Instruments that fit this need.
See
for contacting Hinds Instruments, Inc.