The new optical single-channel rotary joints were developed for single-mode fibers with the requirement “low transmission loss at a simultaneously high return loss.” In an operating temperature range from -40°C to +85°C, the transmission loss for the wavelengths 1310 nm and 1550 nm is a maximum of 1.0 dB, and the return loss is 55 dB.
These very good optical parameters are achieved through the use of fiber optic collimators in combination with a software-controlled alignment method and a special adhesive technique. During alignment, the light beams emitted by the collimators are aligned with the mechanical rotating axis. The coupling losses between two collimators primarily depend on whether the angle was misaligned on either side. Through the use of special ball bearings and individual high-precision mechanical components, the required angular accuracy of the rotatary joints can be guaranteed.
Optical coating of the collimators allows operation in the wavelength range from 1270 nm to 1650 nm. All rotatary joints are available for delivery equipped with standard connectors for SM applications.
