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Reflective optical chopper used in NIST high-power laser measurements



Xiaoyu X. Li, Thomas Scott, Christopher L. Cromer, Joshua A. Hadler


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 wedged-shaped transparent materials (usually crystals) often used as beamsplitters in this type of measurement system. We describe the design, operation and calibration of these choppers. A comparison between choppers and transparent wedge beamsplitters is also discussed.
Journal of Research (NIST JRES) -


attenuator, high-power laser, infrared (IR), K-series calorimeter, laser beamsplitter, laser detector calibration, laser power meter, monitor detector, optical crystal, reflective optical chopper (ROC), ZnSe.


Li, X. , Scott, T. , Cromer, C. and Hadler, J. (2008), Reflective optical chopper used in NIST high-power laser measurements, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 24, 2024)


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Created November 1, 2008, Updated February 19, 2017