OPTICAL AMPLIFIER

摘要

PURPOSE:To allow integration and miniaturization by forming the optical amplifier so as to have a light introducing part which is gradually decreased in waveguide, an optical amplifying part which is narrow in the waveguide width and a light taking out part which is gradually increased in the waveguide width and adding a rare earth element to at least a part of the clad part enclosing the core part of the optical amplifying part. CONSTITUTION:A glass film for a core layer is first produced by a flame deposition method on an Si substrate 1. The narrow optical waveguide 5 is produced by etching on this glass film. The clad part 5a added with Er is formed around the narrow optical waveguide part 5. Signal light and stimulating light propagate to the narrow optical waveguide 5 via the light introducing part 4 of the tapered part by passing the optical waveguide 3 which has the ordinary waveguide and is not added with the Er. The signal light and stimulating light bleed out to the upper clad part added with the Er from the side wall of the core. The intensity of the signal light is then amplified by the inversion distribution and derived release of the Er. The amplified light propagates through the light taking out part 4a of the tapered part again to the optical waveguide 3a which has the ordinary waveguide width and is not added with the Er.