Sources and Detectors Group

Principally through measurement services and innovation, the group provides the optoelectronics industry with traceability to national standards. Activities of the group are currently carried out in three project areas: Laser Radiometry, Laser Applications, and Terahertz Imaging and Sources.

Research in the Photonic Radiometry Project is developing the next generation of high-accuracy optical power measurement standards for laser power, detector spectral responsivity, detector linearity, the attenuation of transmission components, and space-based measurements of the Earth Radiation Budget. To calibrate detectors and instruments used to measure the power or energy produced by a laser, the sun, or reflected by the Earth, the project has developed a family of chip-scale bolometric standards that provide accurate, SI-traceable measurements of optical power with robust, micro-fabricated detectors. Together with standards developed by the Laser Applications Project, these standards permit calibrations at laser power levels from nanowatts to hundreds of kilowatts and energy levels from femtojoules to megajoules. Wavelength ranges include the visible through the near infrared, and selected wavelengths in the ultraviolet and mid infrared. For more information, see the Measurement Services section of this site. Instruments designed to receive power either in collimated beams or through optical fibers can be accommodated.

High power lasers capable of continuous output powers ranging from hundreds of watts to tens-of-thousands of watts present exciting opportunities for rapid, directed delivery of energy – particularly in the area of materials processing and laser machining. These same high power lasers also present difficult challenges for the accurate measurement of their delivered power. The Laser Applications Project exists to enhance NIST's ability to measure high power laser output parameters with the necessary accuracy and ease of use. This is done by developing, testing, and implementing unique technologies such as a thermal flowing-water-based approach and a force-based technique using optical radiation pressure. The Laser Applications Project also makes use of NIST's high power laser facilities to develop technologies and measurement tools associated with laser machining and materials processing. Our 10 kW fiber laser and integrated laser welding booth provide opportunity for the development of supporting metrology for materials processing related to such applications as photovoltaic manufacturing and laser welding.