gentecv106

T 418.651.8003 1 888 5GENTEC F 418.651.1174 www.gentec-eo.com info@gentec-eo.com 8 8 Monitors Energy Detectors Power Detectors OEM Detectors Calorimeters Diffractive Optics Beam Diagnostics CalibRaTiOn HOW IT WORKS THE TECHNIQUE How NIST Calibrates our Gold Standards Electrical Instruments How Gentec-EO Calibrates YOUR Detector Gentec-EO's gold laser power detector heads are compared to NIST standard calorimeters at different wavelengths, in accordance to the different lasers used to calibrate your own detector heads. The laser beam has a nominal diameter appropriate for the detector, and is centered on the detector's absorbing surface. The laser energy impinging upon the test instrument is measured concurrently using a NIST standard calorimeter and a calibrated beam splitter. The beam splitter ratio is measured using NIST standard calorimeters. Before the measurements are performed, the test instrument is allowed to reach equilibrium with the laboratory environment. The calibration factor is found by dividing the instrument output reading by the calculated average incident laser power. The calculation is based on the output reading of the NIST standard calorimeters. See ?gure 1. All of our electrical instruments are calibrated by certi?ed calibration suppliers. They certify that, at the time of calibration, the instruments used for calibration meet or exceed all published speci?cations and have been calibrated using standards whose calibrations are traceable to the NIST and/or other recognized international standards. The electrical and physical properties of their laboratories meet the highest requirements for ambient temperature, relative humidity and cleanliness. Their equipment is maintained by procedures that meet the requirements of ISO 9001:2000 and ISO 10012:2003. Every detector is individually calibrated to the best possible accuracy traceable to NIST standards. Stable laser sources at various wavelengths are used in our calibration process.

T 418.651.8003 1 888 5GENTEC F 418.651.1174 www.gentec-eo.com info@gentec-eo.com 9 Monitors Energy Detectors Power Detectors OEM Detectors Calorimeters Diffractive Optics Beam Diagnostics CalibRaTiOn HOW IT WORKS One very common misconception is the absolute value of calibration uncertainty. Be aware that this value is made using a complex statiscal method that takes in account ALL the sources of uncertainty that are present in the process. Figure 1 below shows these steps and their respective contribution to the value of uncertainty. As you can see, the manufacturer itself is only one of these sources. THE FACTS True Value NIST Reference (±0.3% to ±0.9%) Gentec-EO Gold Standard (±1%) Your Gentec-EO Detector (±2.5%) Maximum contribution from Gentec-EO's calibration setup (? ±1.5%) (Calibrated by NIST) (Calibrated by Gentec-EO using a Gold Standard) Typical Uncertainty of Closest Competition (±3%) Contribution from closest competition's calibration setup (±2%) Order of Calibration Steps +0.5% +1% +1.5% +2% +2.5% +3%-1%-1.5% -0.5%-2%-2.5%-3% Competition Figure 1. Sources of uncertainty in the calibration of a detector Uncertainty Another misconception is that any wavelength can be NIST calibrated: this is not true. The NIST only supplies distinct wavelengths in the range comprised between 193 nm (ArF excimer laser) to 10.6 mm (CO 2 laser). Any wavelength outside this range or other than the ones supplied within the range is subject to an additional error on the calibration value. Calibration Wavelengths To ?ll the gaps between the NIST references, Gentec-EO offers you the only NIST traceable calibration in nm steps, from 250 nm to 2.5 mm. We achieve this using our proprietary setup that is based on a NIST traceable spectrophotometer. This way, instead of supplying you with typical values, we offer you a NIST traceable calibration. What you get is an overall accuracy that is not more than ±1% away from the original calibration accuracy, in the spectrum of 300 to 2200 nm. This data is stored in the Smart Interface so all you need to do is enter your wavelength in your Gentec-EO monitor and you are ready for accurate and precise laser measurements. This wavelength correction is based on measurements of your individual detector instead of a general curve for the absorber material. That means you have the best wavelength correction available anywhere. Personnal Wavelength Correction TM