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Calibration Service for Laser Power and Energy at 248 nm



Rodney W. Leonhardt


This document describes the calibration service provided by the National Institute of Standards and Technology (NIST) for laser power and energy at the excimer laser wavelength of 248 nm. The service supports the calibration of laser power meters form 400 (mu)W to 7.5 W and energy meters from 80 (mu)J to 150 mJ per pulse. Typical measurement uncertainties range from 1.6 to 2.0%. The measurement system, which includes a source laser, beam optics, and NIST reference standard calorimeters, is reviewed. Theory and design considerations for the reference calorimeters which correlate optical energy to NIST electrical standards are discussed. Critical components of the calorimeters and beam delivery system are specified. Measurement system parameters and calibration procedures are examined. Types of laser meters suitable for calibration are delineated. A detailed analysis of sources of error, estimates of uncertainty, and expanded uncertainty are presented.
Technical Note (NIST TN) - 1394
Report Number


beamsplitter, calorimeter, excimer laser, laser power, pulse energy, ultraviolet


Leonhardt, R. (1998), Calibration Service for Laser Power and Energy at 248 nm, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 25, 2024)


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Created January 1, 1998, Updated January 27, 2020