OL 200/220/245 High-accuracy Irradiance Standards
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Gooch and Housego offers 1000-W DXW, 200-W, and 45-W lamps as standards of spectral irradiance, total irradiance, illuminance, and color temperature. These lamps have tungsten coiled-coil filaments enclosed in a small quartz envelope. The lamp OL 200 Calibration standards can be obtained Standard with spectral irradiance calibrations over all or part of the 250 to 2500 nm wavelength region. In addition, the 1000-W DXW and 200-W lamps can be calibrated out to 4500 nm. OL 200, OL 220, and OL 245 High-Accuracy Irradiance Standards PERFORMANCE SPECIFICATIONS 1000-W Spectral Irradiance (nominal) ** @ 250 nm (W/(cm2nm)) @ 1050 nm (W/(cm2nm)) Total Irradiance (nominal mW/cm2) Illuminance (nominal footcandles) ** Transfer Uncertainty * The spectral irradiance standards issued by Gooch and Housego are based on the National Institute of Standards and Technology (NIST) Spectral Irradiance Scale for the wavelength range of 250 to 2400 nm and on a blackbody for the wavelength range above OL 220 Calibration 2400 nm. The NIST Scale Standard has an uncertainty (k=2) of 0.63% in the visible, 1.56% in the ultraviolet at 250 nm, and 0.31% in the infrared at 2000 nm. High-Accuracy Super High-Accuracy Uncertainty * - Illuminance Long Term Photometric Stability Operating Current (amps DC) *Uncertainty is relative to NIST Scale at k=2 **Measured at 50 cm Calibration of the 1000-W DXW and 200-W lamps over the wavelength range of 250 to 2400 nm are available with two levels of accuracy: highaccuracy and super highaccuracy. The High-Accuracy Standards of Spectral Irradiance issued by Gooch and Housego have a transfer OL 245 Calibration uncertainty (k=2) relative to Standard the NIST Scale of ± 1-2%. The Super High-Accuracy Standards have a transfer uncertainty relative to the NIST Scale of ± 0.5%. Total Irradiance Total and Full Spectral Illuminance (only) Color Temperature (only) Uncalibrated (seasoned) For illuminance and/or color temperature calibrations in addition to any of the above calibrations, add the suffix "P" and/or “K" respectively to the appropriate model number. For super high-accuracy calibrations (1000-W or 200-W) add the suffix "S" to the appropriate model number. OPTIONAL ACCESSORIES 1000-W 200-W Lamp Holder OL 56 OL 57W Adjustable Lamp Holder Mount OL 63 OL 63 Programmable DC Current Source OL 83A OL 410 NOTE: In order to ensure consistent and reliable results, Gooch & Housego (Orlando) standards should only be used with current sources that possess a ramp current feature. Contact: sales@goochandhousego.com As part of our policy of continuous product improvement, we reserve the right to change specifications at any time Bulletin 6 / Rev 9-11

High-Accuracy Irradiance Standards The instrumentation and methods used by Gooch and Housego to transfer calibrations from a standard of spectral irradiance to an uncalibrated lamp is patterned after that used at NIST. The measurement procedure employs the highly accurate wavelength-by-wavelength method of comparison (Figure 1). This minimizes the errors associated with setting the lamp current, distance, wavelength, and In this technique, both lamps (standard and test) are operated at the same distance. The spectral irradiance of both lamps is measured at a set wavelength by translating...