| 摘要 |
<p>An optical waveguide formed in an electro-optical substrate includes a curved waveguide (11) having a first end and a second end and a branch portion (12) that is coupled to the second end of the curved waveguide , wherein the curved waveguide (11) comprises a low refraction index portion (18) having an effective refraction index that is lower than that of the rest of the curved waveguide, the low refraction index portion (18) being provided between the first end and the second end of the curved waveguide (11).</p> |
