High-Performance Plastic Optical Fiber Coupler Based on Heating and Pressing

A high-performance plastic optical fiber (POF) star coupler based on the fusing and combining of a group of POFs is presented. The clad removed group of POFs are fused into a combined body by heating and pressing in a rectangular groove. The optical rays are diffused and mixed in the fused and combined region. Based on ray optics, the device structural parameters are designed to obtain a low optical excess loss and equal optical power splitting ratio. This technique was applied for the implementation of a 4 × 4 star coupler. The flatness of the coupling ratios and excess loss were less than 1.1 and 0.5 dB, respectively.