| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical filter which can be provided with stable characteristics and allows a standard ferrule to be used therein. <P>SOLUTION: An optical filter 1 includes a first optical fiber 11, a second optical fiber 12, a photonic crystal optical fiber 13, an optical waveguide layer 14, and a ferrule 17. The photonic crystal optical fiber 13 and the optical waveguide layer 14 constitute an optical resonance part. The photonic crystal optical fiber 13 has a two-dimensional periodic refractive index distribution in a cross section vertical to a fiber axis. The optical waveguide layer 14 is provided between an end surface 11a of the first optical fiber 11 and an end surface 13a of the photonic crystal optical fiber 13. The optical waveguide layer 14 has a higher refractive index than both the first optical fiber 11 and the photonic crystal optical fiber 13. The optical waveguide layer 14 can guide light in a direction different from a light guiding direction in the photonic crystal optical fiber 13. <P>COPYRIGHT: (C)2013,JPO&INPIT |
