Manufacturers of optical coatings and components

The goal of modern UV curing equipment is to deliver the maximum amount of UV energy to the irradiation zone while controlling the heat generated at the substrate. Heat is primarily generated from radiation absorbed by the substrate during processing, although there is some heat generated by the polymerization reactions (cross-linking).  For substrate heating by irradiation, the the degree of heating for any given frequency is a function of the amount of energy supplied by the irradiation source (and focusing optics) at that frequency multiplied by the absorption cross section of the substrate for that frequency (0 - 1.0) . Therefore, maximizing UV energy and controlling heat is accomplished by controlling the frequency distribution at the irradiation zone.

There are two basic optical elements that control the frequency distribution at the irradiation zone:  UV Cold Mirrors and UV Hot Mirrors.  NTFL UV cold mirrors reflect UV energy while removing heat-producing visible and infrared energy.  The removal of visible and infrared energy can be accomplished by transmitting the visible and infrared energy through the reflecting optic (typically fused silica) or by absorbing the visible and infrared energy and transferring the absorbed heat to the reflecting optic (typically aluminum).  NTFL hot mirrors are fused silica heat filters that transmit over 95% of incident UV energy while reducing the transmitted IR energy.

NTFL is the leading worldwide manufacturer of optics for UV curing applications.  We manufacture cold mirrors for a large number of different systems, utilizing both metal reflectors and fused silica or Borosilicate reflectors.