Design And Implementation Of The System For Fabricating Side-polished And Tapered Optical Fiber

The devices that based on side-polished and tapered optical fiber are widely used in the fields of communication, sensor, laser and so on. However, most these systems which using for fabricating side-polished and tapered optical fiber are made from abroad, not only the prices are expensive, but also few parameters can be adjusted, that limit the development of optical devices made from side-polished and tapered optical fiber. It is necessary to develop a new type of high performance micro machining system, which will play an important role in the research of the related scientific and the development of the optical fiber technology.With the demands of producing new high-performance components of optical fiber for micro-machining system and the laboratory research work, we learn the advantages in the existing optical fiber side-polishing and tapering equipments, and designed an integrated system that can fabricate side-polished and tapered optical fiber simultaneously relying on the technology of motion control and micro-measurement of machine vision. This system can control the length of side-polished and tapered optical in 100 mm, and measurement accuracy better than 0.5μm for measuring fiber parameter. The experimental results show that the system is good for fabricating side-polished and tapered optical fiber.The following are the main works in this paper:1. The hardware system for fabricating side-polished fiber and tapered optical fiber was designed and built. The key components include polishing wheel, lighter, fiber clamp, columns, fixed plate, electric displacement table, Grating ruler, lift, DC motor, motor driver, card of motion control, industrial camera, microscope, LED light, optical platform, computer and so on.2. Analyzing the characteristics of motion control technology, we find that displacement table can have high-speed and tiny movement impact when using the trapezoidal acceleration and deceleration planning method to control the stepper motor. Combining with the actual needs of fabricating optical fiber device, we developed the motion and DC motor control program in VC++ environment. Therefore, the control program designed for polishing and tapering is completed, which can control the length of side-polished and tapered optical and can adjust the speed and direction of DC.3.Studying the characteristics of optical fiber image and combining with the high-precision measurement technology of microscope,we developed a program with the help of OpenCV library functions for measuring fiber parameters online,which includes the automatic focusing, sub pixel edge extraction, dimension calculation, calibration and so on.The following are the highlights in this paper:1. We designed a new type of system for fabricating side-polished and tapered optical fiber. It can fabricate side-polished and tapered optical fiber with high-speed, large-range and measure the geometries of fiber with high-precision.2. According to the particularity of optical fiber imaging, an algorithm of edge detection is proposed to extract the ROI region as the focus window. This method can eliminate the influence that the optical band in the center of fiber image brings to definition evaluation value. The image can be accurately determined when the edge of the optical fiber is clear.3. The algorithm of mountain-climb searching is improved and successfully used in high-precision measurement of microscope. Compared with the traditional method, it can overcome the influence of local extreme value and has the ability of high-speed searching.