Reflective Optical Chopper Used in NIST High-Power Laser Measurements.
For the past ten years, NIST has used high-reflectivity, optical choppers as beamsplitters and attenuators when calibrating the absolute responsivity and response linearity of detectors used with high-power CW lasers. The chopper-based technique has several advantages over the use of wedge-shaped transparent materials (usually crystals) often used as beam splitters in this type of measurement system. We describe the design, operation and calibration of these choppers. A comparison between choppers and transparent wedge beampslitters is also discussed.
National Institute of Standards and Technology, Boulder, CO 80305.
Xiaoyu
X
Li
National Institute of Standards and Technology, Boulder, CO 80305.
Thomas
T
Scott
National Institute of Standards and Technology, Boulder, CO 80305.
Chris
C
Cromer
National Institute of Standards and Technology, Boulder, CO 80305.
Joshua
J
Hadler
ZnSe; attenuator; beamsplitter; calorimeter; device under test; high-power laser; infrared (IR); laser detector calibration; laser power meter; monitor detector; reflective optical chopper; visible aiming laser; wedge-shaped transparent material