Manufacturers of optical coatings and components

Dielectric filters are constructed of multiple layers of inorganic oxide materials and transmit restricted ranges of energy.   Bandpass filters such as notch filters, short-pass filters and long-pass filters are common types of dielectric filters.

Dielectric coating technology is commonly used for heat control in optical systems.  Hot mirrors are just a special type of a short-pass filter.  Extending the concept of filtering to reflectors yields an important class of energy selective reflectors known as cold mirrors, which are also important in heat reduction.