Simple Free-Space Method for Measurement of Dielectric Constant by Means of Diffractive Optics with New Capabilities

The monitoring of the composition of materials is an important problem of applied spectroscopy using optical, infrared, microwave and THz wavelength bands. MM and THz waves ensure better spatial resolution than microwaves and they can be used for material testing in media that are opaque for optical and infrared radiation. Whenever dielectric components are used in MM and THz wavebands, a precise knowledge of the dielectric properties of the material is essential. The developments original setups for dielectric material probing simultaneously at several discrete wavelengths within the same local zone are described.