Patent ID: 8416408

Claim:
A scanning monochromater system for application in the Terahertz frequency range, comprising: a narrow-band essentially single frequency source selected from the group consisting of: a Backward wave oscillator; a Backward wave oscillator with multipliers; a Multiple Backward wave oscillators; a Smith Purcell; a Free Electron; a Mixed-laser-beat+Solid State Emitter; and a detector selected from the group consisting of: Golay Cell; Cryogenic Bolometer; Intensity sensitive Solid State Device; between said narrow-band essentially single frequency source and said detector, there being a sample supporting stage with reflection and/or transmission capability; said scanning monochromater system further comprising, between said narrow-band essentially single frequency source and said detector at least one component which is caused to rotate during use, and which is selected from the group consisting of: a rotating polarizer between said source and said sample supporting stage; a rotating analyzer between said sample supporting stage and said detector; a rotating compensator between said source and said sample supporting stage; a rotating compensator between said sample supporting stage and said detector; a stokes vector selector between said source and said sample supporting stage; a stokes vector selector between said sample supporting stage and said detector; such that in use a sample is placed on said sample supporting stage and a beam of electromagnetic radiation provided by said selected source is caused to interact with said sample, then enter said selected detector.