Method for measuring e.g. material thickness of medium, involves determining variable from proportionality constants that exist between frequency changes and phase position of wave, after wave is delivered from path section or sample

摘要

The method involves using continuous, coherent electromagnetic waves in a frequency range of about 50 gigahertz to 10 terahertz. A path section to be measured or a sample (T) to be examined is penetrated by the wave such that frequency of the wave is varied. A variable is determined from proportionality constants that exist between the frequency changes and the phase position of the wave, after the wave is delivered from the path section and/or the sample. Difference of wave lengths is measured by a terahertz interferometer or reference interferometer. An independent claim is also included for a device for measurement of length, space, material thickness, refraction index and absorption characteristics of a medium.