Optical Metrology Laboratory
The NREL Optical Metrology Laboratory ensures that optical radiation resource measurement equipment is calibrated to national or international standards to ensure the quality and traceability of data. NREL considers optical radiation to range from 250 nm to 2,500 nm and to include the ultraviolet (250–400 nm), visible (400–750 nm), near infrared (750–1,100 nm), and shortwave infrared (1,100–2,500 nm) ranges.
The Optical Metrology Laboratory provides National Institute of Standards and Technology-traceable measurements for:
- Spectral irradiance and radiance (250–2,400 nm) scale realization
- The calibration of user spectroradiometers
- The measurement of natural sunlight and artificial source spectral distribution
- Indoor and outdoor solar ultraviolet (250–400 nm) and filter radiometer (photometer) calibrations.
In addition, the Optical Metrology Laboratory provides pulsed/continuous light source characterization that is traceable to National Institute of Standards and Technology standards.
The NREL Optical Metrology Laboratory offers a range of specialized equipment, such as:
- An ASD Inc. FieldSpec Pro fast (200–ms acquisition), wide-range (350–2,400 nm) spectroradiometer
- An Optronic Laboratories OL-750 scanning spectroradiometer with a wide wavelength range (250–2,400 nm) and pulse integration capability
- An Optronic Laboratories OL-756 ultraviolet double monochromator spectroradiometer with a 200–800 nm spectral range
- NREL's Pulse Analysis Spectroradiometer System (PASS), which captures light pulse profiles and determines spectral irradiance at any position within a pulse profile
- An argon mini-arc National Institute of Standards and Technology ultraviolet calibration source for 180–330 nm (water-cooled and requires an argon gas cylinder)
- Portable, spectrally calibrated light sources that consist of constant-output incandescent lamps with measured spectral distribution (require AC power)
- A 150-watt mercury/xenon solar simulator
- Emission line sources for wavelength calibration, including mercury, xenon, neon, and argon penlights and wavelength emission documentation
- National Institute of Standards and Technology-calibrated filter glasses (transmission and wavelength) and reflectance standards
- Integrating spheres of 6-in to 12-in diameters
- Filters, including glass and metal neutral density, wide and narrow passband, cut-on and cut-off glass, and interference types.