What are waveplates made of?
Waveplates are constructed out of a birefringent material (such as quartz or mica, or even plastic), for which the index of refraction is different for light linearly polarized along one or the other of two certain perpendicular crystal axes.
What is polarization retardation?
Retardation – Retardation describes the phase shift between the polarization component projected along the fast axis and the component projected along the slow axis. Retardation is specified in units of degrees, waves, or nanometers.
What is optic retarder?
A retarder (or waveplate) is an optical device that resolves a light wave into two orthogonal linear polarization components and produces a phase shift between them. The resulting light wave is generally of a different polarization form.
What is a zero order waveplate?
Zero-Order Waveplates are made from two Crystalline Quartz or Sapphire plates of similar thickness, that are optically contacted together with orthogonally aligned optical axes. Retardation varies slowly with wavelength, thus they are useful with tunable or broadband sources.
What causes birefringence?
Stress birefringence results when isotropic materials are stressed or deformed (i.e., stretched or bent) causing a loss of physical isotropy and consequently a loss of isotropy in the material’s permittivity tensor.
What is linear retardance?
1: The linear retardance which is induced when light propagates through a birefringent material depends on the axes of oscillation of the light components (i.e. the polarization state).
What is light retardation?
It takes the slow ray longer to traverse the crystal than it takes the fast ray. The fast ray will have passed through the crystal and traveled some distance ∆ beyond the crystal before the slow ray reaches the surface of the crystal. This distance ∆ is called the retardation.
How does a half Waveplate work?
By combining two waveplates whose retardations differ by exactly half a wave, a true half-waveplate is created. The fast axis of one plate is aligned with the slow axis of the other, so that the net retardation is the difference between the two retardations.
What is half wave plate explain?
: a crystal plate that reduces by ¹/₂ cycle the phase difference between the two components of polarized light traversing it — compare quarter-wave plate.
Why do we use quarter wave plates?
Quarter-Waveplates. Quarter-waveplates are used to turn linearly polarized light into circularly polarized light and vice versa. To do this, the waveplate must be oriented so that equal amounts of fast and slow waves are excited.
Which is the best wave plate for achromatic?
This plot compares the theoretical performance for two of our achromatic quarter-wave plates. The wave plate made from quartz and UV sapphire (AQWP05M-580) provides a flatter spectral response over the operating range than the waveplate made from quartz and magnesium floride (AQWP05M-600).
How are achromatic wave plates assembled at Thorlabs?
Our achromatic wave plates are assembled by placing an etched stainless steel spacing ring between two birefringent plates and epoxying the three pieces together. Adhesive is only applied outside of the clear aperture of the wave plate. The fast axis is marked on the three-piece assembly in pencil, in addition to being engraved on the housing.
What can a λ / 2 wave plate be used for?
Mounted on a rotation mount, a λ/2 wave plate can be used as a continuously adjustable polarization rotator, as shown below. Additionally, when used in conjunction with a Polarizing Beamsplitter a λ/2 wave plate can be used as a variable ratio beamsplitter.
What are the two axes of a wave plate?
As described above, a wave plate has two principal axes: fast and slow. Each axis has a different refractive index and, therefore, a different wave velocity.