Most light sources produce large quantities of heat as well as light. Many systems require the separation of heat and light to manage the affects of heat on internal components.  Typical applications include photocopiers, medical instruments, projectors, microfiche systems, and plastic curing. 

JDSU has developed two types of filters using temperature resistant materials and extremely hard, durable coatings to address these needs. These filters take two basic forms: cold mirrors that reflect visible light and transmit heat and hot mirrors that reflect heat while passing visible light.