Accession Number : ADA184538


Title :   Precise Measurement of Refractive Index and Absorption Coefficient of Near Millimeter Wave and Far Infrared Materials.


Descriptive Note : Final rept. 1 Feb 84-31 Jan 87,


Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE FRANCIS BITTER NATIONAL MAGNET LAB


Personal Author(s) : Afsar,Mohammed N ; Button,Kenneth J


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a184538.pdf


Report Date : Jun 1987


Pagination or Media Count : 9


Abstract : A quasi-optical technique, namely, dispersive Fourier transform spectrometry, has now been improved to provide high-precision continuous data of complex refractive index, complex dielectric permittivity and loss tangent of materials and complex magnetic permeability of ferrite materials at millimeter and submillimeter wavelengths. The use of a polarizing two beam interferometric technique allowed a broad frequency coverage in particularly between 6mm and 0.5mm range. Non-polar polymers such as polyethylene and teflon exhibit extremely low-loss characteristics in the entire millimeter wavelength range.


Descriptors :   *REFRACTIVE INDEX , *FAR INFRARED RADIATION , *DIELECTRIC PROPERTIES , *MICROWAVES , SPECTROMETERS , FOURIER TRANSFORMATION , PERMEABILITY(MAGNETIC) , POLYMERS , SAPPHIRE , WINDOWS , RADOMES , SUBSTRATES , BIREFRINGENCE


Subject Categories : Optics
      Electricity and Magnetism
      Miscellaneous Materials


Distribution Statement : APPROVED FOR PUBLIC RELEASE