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Terahertz circular variable filters



Erich N. Grossman, Charles Dietlein, A. Luukanen


We describe a novel class of millimeter-wave and terahertz monochrometers based on adiabatically tuned frequency-selective surfaces. They are analogous to the circular-variable filters commonly used in the infrared for low to moderate resolution spectroscopy, and are well adapted for hyperspectral imaging of explosives, bioagents, and other solid materials that display broad but distinct spectral features in the submillimeter wavelength band. Low-cost fabrication techniques based on copper-on-kapton "flex" circuitboard materials and patterning enable operation to approximately 800 GHz and coverage of areas greater than 0.5 x 0.5 m. Higher frequency operation can be obtained with wafer-based photolithography and standard micromachining techniques. Octave-band prototypes covering 110-220 and 220-440 GHz show resolving powers of >6, presently limited by beamsize in the measurement setup, and insertion loss <0.5 dB.
Proceedings Title
ESA Workshop on Millimetre-wave Technology and Applications
Conference Dates
February 15-17, 2006
Conference Location
Espoo, FI


filter, frequency-selective surface, hyperspectral, millimetre-wave, monochrometer, terahertz


Grossman, E. , Dietlein, C. and Luukanen, A. (2006), Terahertz circular variable filters, ESA Workshop on Millimetre-wave Technology and Applications, Espoo, FI, [online], (Accessed April 22, 2024)
Created February 15, 2006, Updated February 19, 2017