ABSTRACT
Chapter 4 described the deployment of chromatic techniques for monitoring electrical plasma based upon the optical emissions they produce. This chapter describes the use of chromatic methods for monitoring liquids whereby the spectral envelope of light from a controlled source is affected by a liquid through which the light propagates or by reflection from a liquid interface. Wavelength sensing of color changed chemical indicators, e.g., pH acidity indicators, is also described, as well as the use of discrete chromatic processing (see Chapter 2, Section 2.5) of signals from an array of liquid property sensors. The sensing is either by optical fiber, remote, or an array of conventional sensors and transducers.
