The ability to accurately rotate the polarization of incident light while minimizing any losses in polarization purity has applications in optical switching, polarimetry, and microscopy. Polarization rotators utilizing tunable birefringent plates, such as liquid crystal (LC) devices, have the advantage of non-mechanically tuning the devices' retardance. However, these devices properly work with incident light within a very specific wavelength range. Ferroelectric liquid crystal (FLC) devices can switch between two orthogonal states of linear polarization, and offer response times much faster than their nematic liquid crystal cell counterparts. An achromatic polarization rotator can be constructed with an FLC cell between two half-wave plates that have been constructed to produce a half-wave retardance at a certain design wavelength. This results in a device that offers fast response times and high polarization purity over a broader wavelength range.
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