Open resonator operating at 337 μm wavelength

Open-resonator techniques are investigated at the sub-millimetre wavelength of 337 μm A folded spherical resonator with periodic variation of intermirror separation is excited at 33 μm using an HCN laser. Initial results show that the theoretically expected form of resonance spectra can be obtained experimentally, and that the method should be applicable for dielectric-property and scattering-cross-section measurements in this wavelength range.