Prism-grating optical waveguide coupler and optical waveguide device

Abstract

The invention provides a prism-grating optical waveguide coupler and an optical waveguide device with the optical waveguide coupler. The optical waveguide coupler comprises a prism, a grating and a mode convertor, wherein the grating and the mode converter are manufactured on a plane waveguide. Incident light in free space can be coupled to the plane waveguide and converted to be in the ridge type waveguide mode. The prism is a discrete component, and an air gap is reserved between the prism and the grating so that total emission of the incident light in the free space can be achieved on the bottom face of the prism to generate an evanescent field. The grating is manufactured on the plane waveguide, disturbance is caused to the evanescent field through diffraction, and therefore optical energy is coupled in the plane waveguide. The mode convertor is provided with a ridge-shaped portion gradually narrowing down so that the coupled waveguide mode can be converted into a waveguide mode in a ridge-shaped waveguide. The optical waveguide coupler can effectively couple the light in the free space to the waveguide with the high refractive index such as the SOI, the problems of coupling of the ridge type waveguide and mode conversion are effectively solved, and the optical waveguide coupler has the advantages of both a prism coupler and a grating coupler, and is wide in application range, easy to manufacture and convenient to machine.

Description

technical field [0001] The invention relates to the field of optical waveguide technology, in particular to a prism-grating optical waveguide coupler and an optical waveguide device with the prism-grating optical waveguide coupler. Background technique [0002] In the last century, mankind stepped into electronic informatization, and information technology based on computer, microelectronics and communication technology has been widely used in military, scientific research, education, life and other fields. In the 1970s, the appearance of low-loss optical fiber led to the rapid development of optical communication technology, and optical fiber became an ideal transmission medium in various application fields, replacing most of the previous transmission media. But with the development of optical communication, the traditional optical equipment is bulky and bulky, which can no longer meet the needs of further development of optical communication. The researchers proposed to c...

AI Technical Summary

Problems solved by technology

Finding a prism material with a higher index of refraction than silicon is very difficult and obviously prism couplers are not suitable

If a grating coupler is used, the period of the grating needs to be made very short, which is difficult to achieve in terms of grating manufacturing technology

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