High-accuracy optical power measurements by using electrical-substitution cryogenic radiometer

Bazkir, O
Ugur, S
Samedov, F
Esendemir, A
An optical power scale is established at Ulusal Metroloji Enstitusu (UME) using the helium-cooled primary-level electrical-substitution cryogenic radiometer. The scale is established at discrete laser wavelengths of vertically polarized tuneable Ar+, fixed He-Ne, and Nd:YAG (with second harmonic) laser sources. To increase measurement accuracy, laser intensities are stabilized to better than 0.009% using an electro-optical modulator. The spatial profiles of polarized laser beams are cleaned with a spatial filter. The optical power is measured using the static substitution method with an uncertainty of a few parts in 10-4. Repeatability of optical power measurements in the static substitution method, the measurement of window transmittance, and the measurement of power in a scattered beam are the most significant uncertainty components. (C) 2005 Society of Photo-Optical Instrumentation Engineers.


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Citation Formats
O. Bazkir, S. Ugur, F. Samedov, and A. Esendemir, “High-accuracy optical power measurements by using electrical-substitution cryogenic radiometer,” OPTICAL ENGINEERING, pp. 0–0, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/67336.