How can ellipticity angle be negative.

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 Images

	Ulaby1L.png (202.3 KB)
	Ulaby2L.png (186.7 KB)