| WAVEPLATES |
Optical Component > Precision
Optics > Waveplates |
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| Waveplates are necessary elements for variable beam
attenuators, beamsplitters, and optical isolators. Waveplates (retardation
plates or phase shifters) are made from materials that exhibit birefringence.
The velocities of the extraordinary and ordinary rays through the
birefringent materials vary inversely with their refractive indices.
The difference in velocities gives rise to a phase difference when
the two beams recombine. In the case of an incident linearly polarized
beam this is given by a=2pd(ne-no)/l(a-phase difference; d-thickness
of waveplate; ne, no-refractive indices of extraordinary and ordinary
rays respectively; l-wavelength). At any specific wavelength the
phase difference is governed by the thickness of the retarder. ` |
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| Specifications |
| Materials: |
Single crystal quartz |
| Optical Axis:
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Normal to flat edge on circumference of
Retarder |
| Angle of Incidence: |
0 |
| Retardation Tolerance: |
l/300 |
| Diameter Tolerance: |
=0/-0.1mm |
| Wavefront distortion: |
l/10 over central 90% of aperture at 632.8
nm |
| Parallelism: |
1 arc second |
| Surface Quality:
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Ultrafine laser polish, 20-10 scratch and
dig |
| Coating: |
antireflection coating on all air-quartz interfaces |
| Coating Clear
Aperture: |
Central 90% of diameter |
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Half Waveplates |
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Thickness of half waveplaate is
such that the phase difference of which is 1/2 wavelength
or multiple of 1/2 wavelength ... ... |
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Quarter Waveplate |
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Thickness of a quarter waveplate
is such that the phase difference is 1/4 wavelength or multiple
of 1/4 wavelength ... ... |
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Zero-order Waveplates |
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Zero Order Waveplates are used
for where a thickness is required to correspond to a zero
order phase difference ... ... |
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Multi-order Waveplates |
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These multiple order waveplates
are made from a piece of crystal quartz with its optic axis
parallel with the plane of polarization ... ... |
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Dual-Wavelength Waveplate |
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This dual wavelength multiple order
waveplates are made of a piece of quartz which has been precisely
polished. Its thickness is controlled to provide half wave
... ... |
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