Waveplate is an optic in which the polished faces contain the optical axis. All light incidents normal to the surface are composed of components polarized parallel and perpendicular to the axis. In such a device, light polarized parallel to the axis will propagate slower than light polarized perpendicular to the axis. As the light propagates through the optic, the phase shift between the two components with various thickness. The phase shift is called retardance. The most popular retarders in Photonchina are quarter and half wave.
With an appropriate choice of thickness, any degree of retardance may be achieved at any wavelength for which quartz is transparent. However, the minimum thickness necessary to achieve a mechanically strong part corresponds to several full waves of retardance.
Photonchina’s waveplate can transmit light and modify its polarization state without attenuating, deviating, or displacing the beam.It is ideal for applications requiring high damage thresholds and retardation stability over temperature change, such as for use with lasers or infrared light sources.
Waveplates Types:
Photonchina’s waveplates include octadic waveplate (1/8), quarter waveplates(1/4), half wave plates(1/2) and full waveplate.
Both circular aperture and quadratic aperture are available.
Half waveplate
A half waveplate rotates linearly polarized light to any desired orientation. The rotation angle is twice the angle between the incident polarized light and optical axis.
Quarter Waveplate
When linearly polarized light is input at 45deg to the axis of a quarter waveplate , the output is circularly polarized similarly, input circularly polarized light is transformed into linearly polarized light.
The thickness of the quarter waveplate is such that the phase difference is 1/4 wavelength ( λ /4, Zero order) or certain multiple of 1/4-wavelength [(2n+1)λ /4, multiple order].
Production
Photonchina’s waveplates fabrication starts from quartz materials cutting with their axes oriented within a few arcminutes before being polished to a laser-quality finish, arcsecond parallelism, and <λ/10 wavefront. Their thickness tolerance is a only small fraction of a micron. To verify retardation tolerances, specially-trained optical technicians use purpose-built test gear. After anti-reflective coating, zero order and achromatic waveplates are matched in pairs and accurately aligned to each other within their cell mounts.
