Meadowlark Optics Liquid Crystal Variable Retarders

Meadowlark Optics Liquid Crystal Variable Retarders enable precise electrical control of polarization through variation of effective birefringence with applied voltage. This alters the input polarized light to any chosen elliptical, linear, or circular polarization. These retarders are constructed using a birefringent nematic liquid crystal material between optically flat fused silica windows coated with transparent conductive Indium Tin Oxide (ITO) for maximum transmission within a specified wavelength range. Meadowlark Optics Liquid Crystal Variable Retarders are ideal for active polarization control in metrology and medical applications such as stress analysis, pharmaceutical ingredient analysis, and biological microscopy. For uncompensated retarders, there will be a residual retardance of around 30nm at high voltage.

Note: These variable retarders should be electrically driven with an AC waveform with no DC component to prevent ionic buildup which can damage the liquid crystal layer. For control, a 2 kHz square wave of adjustable amplitude is required. The Meadowlark Liquid Crystal Analog and Digital Controllers ensure the drive requirements are met and are recommended for use.