Star coupler for adjustment of light power division ratio and realization method for same

The invention discloses a star coupler for adjustment of a light power division ratio and a realization method for the same. The star coupler disclosed by the invention comprises one channel of input optical waveguide, multiple channels of output optical waveguides as well as a free propagation area and an output optical waveguide entrance transition area located between the input optical waveguide and the multiple channels of output optical waveguides. The star coupler disclosed by the invention overcomes the problem in an original star coupler structure that an output power ratio is limited, wherein parameters such as the radius of the free propagation area, and the width and spacing of an entrance end of the output optical waveguide entrance transition area are adjusted through computer analogue simulation, so that star coupler design with a random output power ratio can be realized. Meanwhile, the device disclosed by the invention has the advantages of a compact structure, less insertion losses and easy processing and implementation.