| 摘要 |
PURPOSE:To obtain exit light having a desired intensity distribution and particularly Gauss distribution by determining the depth of a grating according to the desired intensity distribution of the exit light along the progressing direction of guided light and the intensity of the guided light emitted and attenuated according to such distribution. CONSTITUTION:The depth h(x) is so formed as to be larger toward the progressing direction of the guided light in the grating coupler formed on the optical waveguide so as to lead the guided light propagating in the optical waveguide formed on a substrate to the outside. An electron ray resist is first coated on the substrate to manufacture such grating. The grating pattern is then drawn by an electron beam so as to have the dose distribution periodic in the direction intersecting orthogonally with the scanning direction of the electron beam and in such a manner that the dose at each period corresponds to the depth h(x) in an electron ray drawing device. The resist patter of which the thickness periodically changes and the thickness corresponds to the depth h(x) is formed if the resist is developed after the drawing. The substrate is finally dry etched by an ion beam etching, etc. through the resist pattern.
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