Optical Sources, Detectors, and Systems

Chapter 1

Blackbody Radiation, Image Plane Intensity, and Units

Optical and infrared sources are of two general types, either incoherent such as thermal radiation or coherent such as that from a laser. Here we first treat the classical thermal or blackbody radiation emitted by any body at finite temperature. In particular we are most interested in “room temperature” radiation, that from a body at 300 K, and solar radiation corresponding to the sun’s temperature of 5800 K. Blackbody radiation is incoherent in the sense that there is an infinite set of optical frequencies present and the phase of each constituent frequency term is a random function of the direction of propagation. In contrast, the coherent radiation obtainable from a laser can ...