Optical Methods for Suppressing Speckle

In some applications, such as imaging with coherent light, speckle is a distinct annoyance and ways are sought to reduce or eliminate it. In other applications, such as speckle interferometry in nondestructive testing, speckle is used to advantage and there is no desire to suppress it. In this chapter, we take the former point of view and discuss a variety of ways to reduce the effects of speckle in coherent imaging.