Half
Waveplates |
| |
| The thickness of the quarter
waveplate is such that the phase difference is 1/4 wavelength (True-zero
order) or some multiple of 1/4 wavelength (multiple order). |
| If the angle q (between the
electric field vector of the incident linearly polarized beam and
the retarder principal plane) of the quarter-waveplate is 45, the
emergent beam is circularly polarized. When a quarter waveplate
is double passed, i.e. by mirror reflection, it acts as a half waveplate
and rotates the plane of polarization to a certain angle. Quarter
waveplates are used in creating circular polarization from linear
or linear polarization from circular, ellipsometry, optical pumping,
suppressing unwanted reflection and optical isolation. |
Specifications |
Material |
Crystal Quartz |
Surface Quality |
< 10 /
5 |
Transmitted Wavefront |
< / 10
@ 633 nm |
Diameter Tolerance |
< + 0.00 / - 0.20
mm |
Thickness: |
t 1.0 mm |
Retardation Tolerance: |
< / 500 @ 20 C |
Parallelism: |
< 1.0 arcsec |
Clear Aperture |
> 85% of central dimension |
AR Coating |
R < 0.25% per surface |
|
Half Waveplates