DEVICE FOR MEASURING THE REFLECTION COEFFICIENT,TH

专利名称：DEVICE FOR MEASURING THE REFLECTION

COEFFICIENT,THE DIELECTRIC CONSTANTOR THE THICKNESS OF FOILS OR PLATES

发明人：GUNTER SCHULTEN申请号：US3547543D申请日：19671107公开号：US3547543A公开日：19701215

摘要：1,178,128. Lasers. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 23Nov., 1967 [26 Nov., 1966], No. 53343/67. Heading H1C. [Also in Division G1] A system formeasuring the reflexion coefficient of a low loss or loss-less foil to microwaves, infra-redor light waves incorporates a ring resonator including at least three reflectors A, B, C,defining a ring path for introduced radiation, across which path the foil 8 under test isarranged perpendicularly. Radiation is introduced into the path from a source 9 by apartly transparent mirror 6 or alternatively the path may include a laser medium so thatradiation in it may be provided by stimulated emission. Reflection from the foil under testresults in radiation circulating in the resonator in both directions, giving two possibleresonance modes when the wavelength of the input radiation is suitably related to thepath length within the resonator. These two coupled modes produce resonance peaks atslightly different frequencies, and the frequency difference between these is related,inter alia, to the reflection coefficient of the foil, and the resonant frequency in theabsence of the foil. The frequency difference is ascertained by adjusting the input

frequency so that it passes through the two resonances. The peaks of these are detected

at 11 and the corresponding frequencies noted. The detector 11 may be a rectifier diodecircuit, bolometer or photodiode. If the source is suitably modulated to provide twosidebands, the two resonances may be determined simultaneously. In the systememploying stimulated emission of a laser medium, a sufficiently wide laser line width isused to produce the two resonant frequencies simultaneously in the output. By mixingthese frequencies, e.g. by a photodiode, the difference frequency may be deriveddirectly.

申请人：U.S. PHILIPS CORP.

更多信息请下载全文后查看