Calibration service for laser power and energy at 248 nm

Abstract

Material 13 4.3 Calorimeter Output Analysis 13 4.4 Electrical Calibration of the QUV Calorimeters 15 5. CALIBRATION OF LASER ENERGY OR POWER METERS 5.1 Performance Capabilities of the 248 nm Calibration System 5.2 Calibration of Energy Measuring Instruments 5.3 Calibration of Power Reading Meters 5.4 Laser Meters for Calibration 6. MEASUREMENT UNCERTAINTY 6.1 QUV Reference Standard Calorimeter Uncertainty 21 6.2 Calibration System Measurement Uncertainty 7. MEASUREMENT ASSURANCE 7.1 Electrical Calibration History 25 7.2 Laser Beamsplitter Ratio Measurements 7.3 Check Standard Calibrations to Monitor the QUV System 7.4 Revising the Uncertainty Sources from Accumulated Data 8. FUTURE CALIBRATION SYSTEM CHANGES 9. REFERENCES 111 APPENDIX A. Sample Calibration Report 29 APPENDIX B. Calibration Procedure Outline 33 APPENDIX C. Shipping Instructions 34 TRADE NAME DISCLAIMER Certain commercial components used in the calibration system are identified in this report in order to adequately document the design. Such use and identification do not imply recommendation or endorsement by NIST, nor do they imply that the items are necessarily the best available for the purpose.

Bilateral comparison of power measurement standards for KrF excimer lasers between PTB and NIST

“…First, the transfer detector was calibrated at PTB with the standard detector for average laser power at the wavelength of 248 nm. This transfer detector was then sent to NIST and calibrated with the NIST 248 nm primary standard calorimeter [1,2]. Afterwards, the transfer detector was again calibrated at PTB in order to take into account a change in its responsivity caused by transportation, irradiation during the calibration process, damage etc.…”

“…The responsivity of the DUT is then determined with the help of the responsivity s M of the monitor detector determined in step 1, i.e. : (2) with V DUT , V M2 : signals of the DUT and monitor detector (2. step), respectively, s DUT : responsivity of the DUT, ) 2 : laser power (2. step).…”

“…3 [2]. The spatial filter, consisting of two UV-grade lenses (focal length | 35.4 cm and focal length | 30.4 cm) and an adjustable circular aperture, was used to produce a circular beam approximately 1 cm in diameter at the detector plane.…”

“…The measurement uncertainty budget was determined using the guidelines in [8] and is described in detail in [2]. All of the Type B uncertainty Fig.…”

The candela and photometric and radiometric measurements

“…As a compromise between damage-threshold levels and desirable heat diffusion characteristics, the absorber material is chosen such that its inherent value of α allows complete absorption within a thickness of 1 mm to 2 mm. Using this guideline, glass absorbers have been applied to infrared [ 76 ] and ultraviolet [ 77 , 78 ] laser measurements. Even though volume-absorbing materials minimize thermal damage, materials used in calorimeters must also be free from other effects, such as fluorescence and degradation, when exposed to laser pulses.…”