| 摘要 |
PURPOSE:To obtain an optical module of integral structure whose optical axis is high in stability by a method wherein two exciting light is made to impinge on a prism of double refraction crystal as a normal light and an abnormal light at certain angles and then emitted from the same point at the same angle with the side face of the prism to compose a double exciting light. CONSTITUTION:A wave-length division multiplexing film (WDM film) 22 is evaporated on the one side of a double refraction crystal 21 to constitute a light path in the double refraction crystal 21 where light is reflected and refracted, whereby the crystal 21 has such a function that two exciting light is formed into a double exciting light, and signal light and exciting light are multiplexed or branched off. That is, when two exciting light whose polarized wave fronts are vertical to each other are made to impinge on the side of the crystal 21 opposite to its other side where the WDW film 22 is evaporated as a normal and an abnormal light at adequate angles, the two light is reflected by the WDW film 22 and injected into an erbium-doped fiber as a double exciting light emitted from the opposite side. Signal light amplified by the erbium-doped fiber is made to impinge on the WDW film 22 and then projected out of the crystal 21 at an incident point, because the WDW film 22 is treansmissive to signal light. |
