A Far Infrared Interferometer

ESPRIT – A Far-Infrared Space Interferometer

In the far-infrared (FIR) / THz regime the angular (and often spectral) resolution of observing facilities is still very restricted despite the fact that this frequency range has become of prime importance for modern astrophysics. ALMA (Atacama Large Millimeter Array) with its superb sensitivity and angular resolution will only cover frequencies up to about 1 THz, while the HIFI instrument for ...

Upgrade of the Electronics of the JET Far Infrared Interferometer

Studies of resonantly produced plasmas in the H-1NF heliac using a far-infrared scanning interferometer

The H-1NF heliac regularly operates using the ion cyclotron range of frequencies at 0.5 T to produce plasmas with a mixture of hydrogen and helium gases. Due to the complex three-dimensional structure of the magnetic flux surfaces, these plasmas require sophisticated diagnostic systems, with good spatial coverage, to extract meaningful physical information. This article presents a study of the ...

A simple far-infrared laser interferometer for measuring electron densities in reactive low-temperature plasmas

A sensitive far-infrared fir interferometer for electron density measurements in reactive low-temperature plasmas is described. The instrument is based on an optically pumped fir laser wavelength range 50–600 m depending on the working gas and makes use of the nonlinear relation between output power and cavity loss. The fir beam, which leaves the resonator through a coupling hole in the end mir...

Infrared point diffraction interferometer.

The point-diffraction interferometer (PDI) is a simple common-path interferometer capable of measuring optical-path differences (OPD) directly. This interferometer, first described by Smartt in 1972,1,2 has since become available commercially for use in the visible spectrum. Currently activity in laser-fusion and high-energy-laser systems has stimulated interest in extending PDI principles to t...