| 摘要 |
PURPOSE:To concentrically advance a second higher harmonic which is projected into a substrate, and also, to improve the utilization efficiency of a fundamental wave by forming a part for bringing the second higher harmonic of the substrate to wave-guide by a material whose refractive index is higher than that of other part of the substrate, and also, whose refractive index is lower than that of an optical waveguide. CONSTITUTION:As for an optical wavelength converting element 10, an optical waveguide 11 is formed by filling a part between two pieces of glass substrates with a non-linear optical material, and in its center part, a high refractive index part 12a for extending over the overall length of the substrate is formed. A laser light (fundamental wave) 15 is made incident on the inside of the optical waveguide 11 from an element end face 10a, and converted to the second higher harmonic 15' whose wavelength is 1/2. This second higher harmonic 15' repeats total reflection by the interface of the high refractive index part 12a and other part and advances in the element 10 in a confined state, and from a light emitting end face 10b, a beam 15'' on which the second higher harmonic 15' is concentrated in a high level is emitted. Also, the fundamental wave 15 advances concentrically in the high refractive index part 12a in the same way. |
