Of all subdisciplines of micro-optics, reflective micro-optics is perhaps the simplest from the optical point of view, yet the most successful commercially. Micromirrors are manufactured by the billions, and their simple optical function, namely to reflect an incident light beam, is the basis for a significant sector in the home entertainment industry on the one hand, and forms the backbone for the fiber networks on which the planet relies on the other.

We will see in the sections below how micromirrors have revolutionized video beamers and have become the mainstay for optical telecommunications. Beginning with a basic analysis of reflection for planar, parabolic, and spherical mirrors, we will subsequently look at the basic technology of micromirrors, their structure, optical behavior, and means for actuation. A special case for reflective micro-optics is that of adaptive optics, which relies on mirror arrays or deformable single mirrors to correct a distorted wavefront, and has become an essential component in medical and astronomical imaging systems. Finally, as micromirrors represent advanced technological products, we will examine a few case studies, showing where you are likely to have already encountered one of these components.

Reflection

Reflective micro-optics relies on reflection of an optical field from a mirror surface, which is, at least in its basics, relatively easy to understand. In striving for high reflectivity for ever larger wavelength ranges, engineers continue to study reflection both theoretically and experimentally, and this seemingly well-developed topic is still the subject of a fair amount of research activity.