KS Photonics Inc.

Computer-controlled variable-ratio coupler (CTDC)  is an all-fiber construction and provides the tuning range of 0 – 100 % coupling ratio with negligible optical loss. The servo motor actuator facilitates the fine-tuning coupling ratio through the motion controller. A computer-controlled version allows user-customized operation during the experiments.
It is based on evanescent field coupling using two side polished fibers where the coupling ratio is tuned by adjusting the core-to-core geometric offset. Customer specified fibers and operating wavelengths are available including single-mode fibers, polarization maintaining fibers and other specialty fibers.


• Negligible loss
• Polished fiber coupler
• Tunable coupling ratio (0-100%)
• Available with various fiber types including SMF and PMF
• Controlled by the linear actuator
• Actuator & Driver included
• Compatible with 1⁄4’’-80 Threaded actuator ( 1⁄4’’-80 mounting bush)
• Available with body only option (without actuator)
• Very small size


• Optical system testing
• Interferometry
• General laboratory experiments
• Optics education kits


Type: Directional Couplers