The NIST Laser Power and Energy Calibration Project develops and maintains the U.S. national standards for the characterization of lasers, along with detectors and other optical and optoelectronic components used with lasers and in laser-based systems. These standards support applications of lasers in manufacturing, electronics, medicine, communications, and the military, among other fields, and are generally used to provide calibrations of instruments used in these areas.
For calibrating instruments used to measure the power or energy emitted by a laser, specially designed standards consisting of calorimeters, pyrometers, thermal radiometers and diode traps have been used for many years. Low-level laboratory standards are realized using solid-state photodetectors. In addition, the Division has developed an ultra-high accuracy laser power measurement capability using a Laser Optimized Cryogenic Radiometer (LOCR).
Well-characterized transfer standards (calibrated against the primary standards) are maintained as laboratory standards for calibrations and for use in divisional and Measurement Assurance Program (MAP) intercomparisons. The traceability to SI constants for all services is accomplished through thermal radiometers and electrical substitution techniques. In a continuing process, new standards are being developed and implemented to expand and improve service capabilities.