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Classical Electrodynamics Applied in Modern Technology

This document explores the properties and applications of nano-metal films in modern technologies, particularly in electromagnetic absorption. It highlights their use in anechoic chambers, examining designs like pyramidal absorbers and hybrid systems for effective EM radiation management. Key principles such as frustrated total internal reflection and impedance variation are discussed, alongside innovations in rain-sensing wipers. The research includes insights from notable physicists and includes patents related to the application and development of these advanced materials.

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Classical Electrodynamics Applied in Modern Technology

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  1. ClassicalElectrodynamics Applied in Modern Technology • 1. Properties of Nano-Metal Films Günter Nimtz Physics Department, University of Cologne • 2. AnechoicEMC Chambers: Pyramidal Absorber • Absorption byAnechoic Traps: ReflectingCurtains • 4. Ferrite Tile Absorber……….Hybrid Absorbers • Rain SensingWipers: Frustrated Total Internal Reflection = Tunneling

  2. Free carrierEM interaction : Drude (1900), Hagen & Rubens (1902) Nano metalfilms(gravimetricaldetermination !) Infraredstudies on Absorption, ReflectionandTransmission: A + R + T = 1 Murmann; Barnes; Czerny; Woltersdorff (1929 – 1934)

  3. R A T R + T + A = 1 of Nano-Film Resistance Angle ofincidence =   = 900 • > d T = {1 + Zo/(2 Z)}-2 ; Zovacuumimpedance Z =/d sheetresistance d film thickness TM = 450 EM  = 450

  4. Howtoget a hugemetalcavitybehavelikefreespacewith : ZO = 377 Ω, i.e. nostandingwavepatterns? Installabsorbersatthewalls! EM anechoicchambers Installabsorbersatthewalls! Metalwalls

  5. EM AnechoicChamber

  6. Nano-Metal-Film, a 10 nmmetal film vapordepositedon 10 µm polyethylenefilm

  7. Sheet ResistanceZisRelevant for Wave Propagation if» d : Z= 1/( d) d d  = conductivity d = film thickness  = wavelength Foam≈10-7 Nano-MetalFilm (≈ 0.1 S/m) (≈ 106S/m)   2.4 m International Patents: G. NimtzandA. Enders (1998)

  8. Standing Waves in Front oftheMetal Wall Variation ofimpedancewithpositionalongtheline(Smith Diagram) Z AbsorbingPyramids: Absorption with Low Reflection  Z = 0 Foam E Nano-film E = electricfield

  9. Metal VacuumImpedance Z0 = 377 Ω E /4 Z = Ω ≈377 ΩShunt NoReflection The variationofimpedancewithpositionalongtheline (Smith Diagram)

  10. R A T R + T + A = 1 of Nano-Film Resistance Angle ofincidence =   = 900  > d Special Property : For 188 Ω: 0.25 + 0.25 + 0.5 = 1 TM = 450 EM  = 450

  11. NovelPrinciple, Device under Test: Absorption by Multiple Reflection e.g. 8 Reflections: R(total) = 0.258 - 48 dB; dB = 10 lg(P1/P2) Anechoictrap Transmitter nano-Metal Films Metal Wall NimtzandPanten, Ann. Phys. 19, 53 (2009); Pending Patents, G. Nimtz (2008)

  12. Curtainsofnano Films insteadofPyramids atonewall asshownnextfigure

  13. EM Anechoic Chamber

  14. In small Chambers: Ferrite TileswithZF ≈ Z06.3 mm; 30 MHz – 300 MHz (< -20 dB, regulation) Hybrid Absorber: Pyramidal Absorber + Ferrite Tile (30 – 18 000 MHZ) ZF = Z0 µr/r = Z0 ! Reflection R: R = (n1 – n2)/(n1 + n2) = (ZF – Z0)/ZF + Z0) Metal Wall

  15. Ferrite tiles TDK (Ni-Cu-Zn) :

  16. Rain sensingwiper: frustrated total reflection

  17. glass n1 > n2 air Total Reflectionif: sin  n2/n1 tot = arc sin(n2/n1) Frustration :   tot  ß

  18. The double prisms: frustratedtotal internalreflection The analog ofquantummechanicaltunneling Sommerfeld (1954)

  19. Front windshield Rain SensingWipers: Frustrated total reflexion Rain representsthesecondprism LED Rain……. Prism Receiver

  20. SummingUp : • Nano-Metal Film Absorbers areBroad Band Absorbers, Superior toCarbonizedFoam Absorber • Incombustible. Non-Toxic.NoHazardousWaste • Nano-Metal Film Absorbers on Dutysince 1995 • Ferrite Tiles, verythin but expensive (30-400 MHz) • Frustrated total internalreflectionas rain sensingcardevice. • Double Prisms:Newton 1700, BOSE 1900, Sommerfeld 1954

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