This work began in the 1980's in response to a lack of traceable standards in the mid-infrared spectral region. The main driver has always been the needs of industry to measure infrared optical properties accurately. In recent years Quality Assurance systems in industry have also underlined the need for traceable measurement. Infrared optical properties are important across a range of applications including spectroscopic analysis in pharmaceutical and chemical industries, thermal control in buildings, infrared tracking and guidance systems and both instrumentation and thermal control in satelites.
All measurement is subject to some degree of uncertainty or error.
The measurements and provision of standards from NPL are currently based on the use of grating spectrophotometers, the sources of error of which are well understood and can be evaluated. Whilst conveying many advantages to most users, the many possible intrinsic sources of error are not as easily separable 1 . However, original research is under way to allow use of this instrumentation at NPL, firstly for measurment services, and eventually for the underpinning basic standards work.