Achromatic input/output coupler for integrated optical circuits

摘要

In order to stabilize the coupling angle, at which light is coupled into and out of an optical waveguide of an integrated optical circuit or the like, with changes in wavelength of the light (to achromatize the coupling angle characteristics of the waveguide input/output coupler) a hybrid prism/grating coupler is used. The grating produces achromatic coupling over a range which can be as large as 200 nanometers (nm) for typical waveguide materials by compensating for the dispersion due to the change in the effective mode index of the waveguide and the prism with variations in wavelength.