The Quater- and Half-Wave Achromatic Wave Plate Modules feature a compound-plate design that uses Crystal Quartz and MgF₂. The plates are air spaced to provide a high-power beam path that has excellent wavefront error and minimum beam deviation. These modules, which are available with three different AR coatings, are mounted on our RCB Rotation Mount, enabling rotation through 360° with a 1.5° resolution. The AR coating only contributes an additional insertion loss of 0.1 dB per component. Modules can be removed and replaced with no change in insertion loss. Achromatic wave plates have a flat spectral response that make them ideal for applications that have greater than 20 nm bandwidths. Quarter- and half-wave modules can be added to create polarization controllers, PM fiber launch systems, and other devices.

Polarization Controller

We currently offer a Polarization Controller Kit consisting of the Adjustable U-Bench, two quarter-wave plates, and one half-wave plate. The U-Bench controller has the same function as a paddle controller, while offering a more deterministic and stable polarization manipulation. Since it does not have any hysteresis, it is possible to predict the controller's output State of Polarization (SOP) at any instant in time given only its input SOP. Hysteresis describes the lag that exists between the responding parameter and the changing parameter or, in this case, the time lag between the SOP change and the moving of the fiber paddles.

In any system with hysteresis, like a fiber paddle controller, there is no way to predict the output. When a paddle controller is adjusted, the SOP takes time to stabilize and may not stabilize at the intended value. Furthermore, without a polarimeter, the SOP from the paddle controller cannot be determined directly. With the U-Bench Polarization Controller, any input polarization state can be deterministcally rotated into a known output polarization state using a quarter-wave, half-wave, and another quarter-wave plate mounted (in this order) between the two FiberPorts of the Adjustable U-Bench. Each plate can be precisely and continuously rotated through 360°.