Proc. SPIE. 9685, 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems; and Smart Structures and Materials
At present, the splitting ratio test of the waveguide coupler usually adopts optical fiber coupling test method. The coupling process is complex and the coupling loss is different in two pigtail fibers, what can result in error in the splitting ratio. A new method for testing the splitting ratio of waveguide coupler using laser beam profiler is presented. Laser beam profiler is used to scan the horizontal directional light field in the cross-section of the waveguide. The measurement data are obtained. Data fitting and processing is carried out by data processing program. Finally, two light field curves are gotten, and the splitting ratio of the waveguide coupler is calculated. The feasibility of the new method is verified using fiber coupler. The error using the new method is only 0.68%. The waveguide coupler testing platform is built. The relationship between the measurement range of the splitting ratio and the minimum distances of the waveguide coupler is analyzed. The research provides an effective and convenient method for the test of splitting ratio of waveguide coupler.