48
Views
21
CrossRef citations to date
0
Altmetric
Special Issue Paper

High-quality blackbody sources for infrared thermometry and thermography between −40 and 1000°C

&
Pages 15-22 | Received 03 May 2000, Accepted 07 Aug 2000, Published online: 06 Oct 2016
 

Abstract

The National Physical Laboratory (NPL) has designed and constructed four high-quality infrared (IR) blackbody sources to provide standards for the calibration of IR thermometers and thermal imaging systems. These are based around heat-pipe technology and are delineated by the working fluid of the cavity; ammonia (from −40 to + 50°C), water (from + 50 to + 275°C), caesium (from + 280 to +600 °C) and sodium (from +500 to + 1000 °C). The emissivities of these cavities are in excess of 0.999 and the expanded radiance temperature uncertainties [U(k = 2)] range from less than 0.1 °C at lower temperatures to about 0.2 °C at 1000 °C. The sources are used to provide traceability to the International Temperature Scale of 1990 via a calibration service, accredited by the UK Accreditation Service (UKAS) (Calibration Laboratory 0478).

This paper describes the general design of the NPL blackbody cavities and their performance. It then describes the use of the blackbody cavities for testing two different commercial thermal imagers. Imager 1 is based on scanning technology; imager 2 has a focal plane array detector package; both systems operate within the 3–5 μm atmospheric transmission band. The parameters tested are the temperature accuracy, uniformity across the image plane, effect of range setting on output and sensitivity to atmospheric carbon dioxide.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.