ABSTRACT
The word “radiometry” means the radiation measurement. The term radiometer is usually exclusively applied to the devices that measure radiance. However, this term is used in a more general sense for a device that measures one of several power-dependent optical quantities. Radiance, defined as the optical power emitted from an area within particular solid angle, is one of many optical terms that will be defined and treated in this chapter. The corresponding mathematical techniques for calculating the radiative transfer as well as the measurement techniques for characterizing of fluxes and radiometric properties of different kinds will be included in this chapter.
