title: Multilayer interference filters for the far-infrared and submillimeter regions.
abstract: The theoretical and experimental aspects of an alternative approach to the construction of interference filters for wavelengths greater than 80 microm are described. The filters consist of a number of thin plastic sheets with films of a high refractive index deposited onto one or both sides of each sheet. These are then heat bonded to form a self-supporting optical multilayer filter. Experimental results are presented for a number of filters produced in this way. Reflectances of the order of 90% have been measured for wavelengths as high as ~200 microm. By successive reflections from two or more such multilayers it is possible to produce efficient, narrow-bandpass filters with blocking over extended spectral regions. The possibility of the construction of other devices, including even narrower bandpass filters and wideband beam splitters, is also discussed.
authors.forename: J
authors.initials: J
authors.lastname: Shao
authors.forename: J A
authors.initials: JA
authors.lastname: Dobrowolski