MODULATORS :: APPLICATIONS :: Intensity Modulation
The PEM modulates light polarization. When a PEM is used between two crossed polarizers, the set-up can modulate the intensity of a light beam (chopping). This intensity modulation is at a fixed frequency between 40 and 200 kHz.
SETUP
Chopping frequency: PEM’s 2nd harmonic (2f)
OBTAINED WAVEFORMS
APPLICATIONS
“Chopping” at tens of kHz without moving mechanical parts, vacuum UV to mid-IR
TYPICAL PEMs
I/FS50
II/ZS50
AVAILABLE INSTRUMENTATION
High Speed Optical Chopper
FURTHER READING
T. C. Oakberg and B. Wang, Application note - Light Intensity Modulation Using A PEM, Hinds Instruments, Inc. (1995).