Spectral Selectivity

doi:10.1117/3.2512522.ch3

Book: Spectrally Selective Surfaces for Heating and Cooling Applications

Editor(s): Claes-Goeran Granqvist

Published: 1989

https://doi.org/10.1117/3.2512522.ch3

Abstract

Spectral selectivity, as a means to achieve energy efficiency, rests on the radiative properties of our ambience. These are illustrated in Fig. 3.1 with a common logarithmic wavelength scale on the abscissa. The most fundamental property is that matter emits radiation. Its character is conveniently discussed by starting from the ideal blackbody, whose emitted spectrum - known as the Planck spectrum - is uniquely defined if the absolute temperature is known. Planck's law is a consequence of the quantum nature of electromagnetic radiation.