How can ellipticity angle be negative.


by yungman
Tags: angle, ellipticity, negative
yungman
yungman is offline
#1
Jan16-13, 08:47 PM
P: 3,843
In plane wave elliptical polarization, the book said if the Ellipticity angle is possitive, it is a Left Hand Circular polarization(LHC). If Ellipticity angle is negative, it is Right Hand Circular polarization(RHC).

My question is how can Ellipticity angle be negative?

http://en.wikipedia.org/wiki/Polarization_%28waves%29

Can anyone show a picture of negative Ellipticity angle?

In case this sounds ridiculous, attached is the scan of the paragraph from the "Engineering Electromagnetics" by Ulaby. I have to scan in two part to fit the size limit. First is Ulaby1 and then Ulaby2.

Thanks
Attached Thumbnails
Ulaby1L.png   Ulaby2L.png  
Phys.Org News Partner Physics news on Phys.org
Physicists design quantum switches which can be activated by single photons
'Dressed' laser aimed at clouds may be key to inducing rain, lightning
Higher-order nonlinear optical processes observed using the SACLA X-ray free-electron laser
DrDu
DrDu is offline
#2
Jan17-13, 10:09 AM
Sci Advisor
P: 3,369
I don't see what is the problem with a negative ellipticity angle.
The sign of the arcus tangens is not fixed by it's argument, it can be either positive or negative. To decide which one to choose, you have to look at the polarisation of the wave.
yungman
yungman is offline
#3
Jan17-13, 10:57 AM
P: 3,843
Quote Quote by DrDu View Post
I don't see what is the problem with a negative ellipticity angle.
The sign of the arcus tangens is not fixed by it's argument, it can be either positive or negative. To decide which one to choose, you have to look at the polarisation of the wave.
The question is how to draw a negative ellipticity angle physically?
[tex]\chi\;=\;\tan^{-1} \frac {a_{\eta}}{a_{\epsilon}}[/tex]
Both are just length and is never negative.


Register to reply

Related Discussions
very high value of negative camber angle Automotive Engineering 4
Negative angle projectiles Introductory Physics Homework 3
Intro and a Question About Ellipticity General Astronomy 3
Tan of ugly (negative angle) Precalculus Mathematics Homework 2
Positive / negative angle help plz Introductory Physics Homework 9