| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical waveguide wherein a mode field diameter is effectively changed by forming cores different in width and height of both end parts within the same surface and to provide its manufacturing method. SOLUTION: In the method for manufacturing the optical waveguide in which the cores having a part where the mode field diameter is changed are formed on an under clad, grooves 14 having the part in which the ratios of widths w1, w2 to depths h1, h2 are equal and the widths are gradually changed are formed by dry etching on the under clad 11, core material is deposited on the under clad 11 in which the grooves 14 are formed, core material deposited excepting the grooves 14 is removed and the cores 12 different in widths w1, w2 and heights h1, h2 are simultaneously formed within the same surface. |
