Lyot Depolarizer

The depolarizer consists of two crystalline plane parallel plates which are cut parallel to the optic axis. The thickness ratio of the plates is exactly 2:1. The two plates are optically contacted. The optical axes of the individual plates form a 45° ± 5' angle. The wedge error of the combination is less than 2". The deformation of a transmitted plane wave is less than λ/5.
The depolarization is created by the superposition of the circularly, elliptically and linearly polarized light in different wavelengths. The depolarizer is not for use in monochromatic light.
All models are delivered with octagonal shape. The total thickness is 6 mm (4 mm + 2 mm).

Material: synthetic quartz crystal

Spectral range about 180 nm to 2.8 µm. Unmounted.

Material: Calcite

Spectral range about 250 nm to 2.5 µm. Unmounted. The birefringence of calcite is about 17 times higher than of quartz. So, with the same plate thickness, this depolarizer can be used in narrower spectral ranges.

Material: MgF2

Spectral range about 125 nm to 7 µm. Unmounted.

Accessories

• Cylindrical engraved holder → PDL 0

Literature

B. Lyot, Annales de l'Observatoire de Paris (Meudon) Tome VIII, Facs. I (1929) "Recherche sur la polarisationde la lumière des planètes et de quelques substances terrestres"
K. Mochizuki, Appl. Opt. 23 (1984),3284, "Degree of polarization in jointed fibers: The Lyot depolarizer"