The microelectronic technology

which uses electrons as its information carrier

is currently running into the bottleneck of development.As optical communication is characteristic of broad bandwidth and high transmission rate

it is an inevitable trend for the development of future information transmission to integrate photonic carriers with electronic carriers.The highly-efficient coupling between waveguides and fibers is the key to realizing photoelectronic integration.This paper reviews the latest advances in the development of several typical couplers at home and abroad

including the tapered coupler

Gradient Refractive Index（GRIN）lens coupler and vertical grating coupler.In addition

it compares and analyzes their performance indexes

advantages and disadvantages and predicts the feasibility of further improving their coupling efficiencies.The results show that with the advantages of high coupling efficiency

wide bandwidth

mature technology

large process tolerance and simple coupling steps

vertical granting couplers have a broad prospect of applications in the fields of optical communication and integrated optoelectronics.