Module 4 a - Page 1 Page 1 Module 4 Lecture 1 Thin film...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Page 1 Page 1 Module 4 Lecture 1 Thin film coatings: Reflection properties Page 2 On the program today An EM wave incident at normal incidence on two boundaries in a row. What for? Antireflection coatings for media with different dielectric constants: optical glasses, cameras, computer and cell displays, radar cloaking Lossless weather shields for radars Passband filters with designed filtering shapes Using wave interference effects to trick Maxwells equations Page 3 Generic case: time harmonic x-polarized TEM wave Z=0 Z=-L Medium 0 Medium 1 Medium 2 Take m r =1 in all media. Linearly polarized TEM wave allows us to use scalar equations for E Question: for a given wave incident from the left onto boundary 01, what is the reflected wave in 0 and transmitted wave in 2 Page 4 Write down the E-field phasors in the three regions of space Z=0 Z=-L Medium 0 Medium 1 Medium 2 z j i e E z j r e E z j t e E 2 z j i e E 1 1 z j r e E 1 1 Page 5 Write down the E-field phasors in the three regions of space Z=0 Z=-L Medium 0 Medium 1 Medium 2 z j i e E z j r e E z j t e E 2 z j i e E 1 1 z j r e E 1 1 + + We have ten unknowns (5 E-fields and 5 H-fields) minus 1 arbitrary (the amplitude of the incident E-field). But we also have 4 boundary conditions (2 for tangential E and 2 for tangential H), and 5 equations for the E/H ratios in all media (the local wave impedance). SO THERE IS A UNIQUE SOLUTION! Page 6 Solution: start to match from the region where...
View Full Document

Page1 / 24

Module 4 a - Page 1 Page 1 Module 4 Lecture 1 Thin film...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online