Abstract: A method of manufacturing an optical waveguide device with low scattering loss is provided. This method comprises, in the following order, the steps of forming a groove by etching in a cladding member having a glass region including a first dopant that lowers the softening temperature of the glass region, heat treating the cladding member at a temperature that is higher than the lowered softening temperature, forming a core within the groove, and forming an overcladding layer composed of glass including a second dopant over the core and the cladding member. Alternatively, this method comprises the steps of forming a groove by etching in a cladding member having a glass region including one of elemental germanium, elemental phosphorus, and elemental boron, heat treating the cladding member after the formation of the groove, forming a core within the groove, and forming an overcladding layer over the core and the cladding member.

Abstract: The present invention provides a glass optical waveguide device that comprises silica glass and is usable despite a relatively large refractive index difference between its core layer and cladding layer, and a method of manufacturing such device. This optical waveguide device includes a core layer on or over a substrate and a cladding layer that covers the core layer, wherein the core layer is made of silica glass containing an additive for raising the refractive index, and the relative refractive index difference of the core layer with respect to the cladding layer is at least 2.5%.

Abstract: An optically amplifying waveguide that can have a gain having a small wave-length dependency in a wavelength range shorter than the C-band, and the like. The optical amplifier module 1 optically amplifies a signal lightwave that has a wavelength lying in a wavelength range of 1,490 to 1,530 nm and that has entered an input connector 11 to output the optically amplified signal lightwave from an output connector 12. An optical isolator 21, a WDM coupler 31, an Er-doped optical fiber (EDF) 50, a WDM coupler 32, and an optical isolator 22 are provided in this order on a signal lightwave-transmitting path from the input connector 11 to the output connector 12. A pump source 41 connected to the WDM coupler 31 and a pump source 42 connected to the WDM coupler 32 are also provided. In the EDF 50, at least one of the stimulated-emission cross section and the absorption cross section assumes a maximum value at the shorter-wavelength side of a peak at a wavelength range of 1.53 ?m.

Abstract: The present invention relates to an integrated optical element and so forth in which an optical waveguide having favorable characteristics such as polarization dependence is integrated with an optical semiconductor element. The integrated optical element comprises a silicon bench having an element mount surface; an optical circuit element; and an optical semiconductor element. The optical circuit element includes an optical waveguide in which a grating is formed, and a substrate different from the silicon bench, and the optical semiconductor element constitutes an external resonator together with the grating. The optical circuit element and the optical semiconductor element are fixed onto the element mount surface of the silicon bench via a bonding material, while being apart from the silicon bench at a predetermined distance.

Abstract: A compound of the following formula or a pharmacologically acceptable salt thereof: 1

Abstract: A process for producing fluoride glass, including the steps of: introducing a raw material for fluoride glass into a heating vessel; and heating the raw material in the heating vessel, while causing the heating vessel to have a negative internal pressure and introducing an inert gas into the heating vessel, thereby to melt the raw material under heating.

Abstract: This invention relates to a dispersion-compensating fiber which can be drawn at a lower temperature and can further reduce optical transmission loss. This dispersion-compensating fiber comprises a core portion containing a high concentration of GeO.sub.2 and a cladding portion formed around the outer periphery of the core portion. The cladding portion comprises a first cladding containing fluorine or the like as an index reducer, a second cladding having a higher refractive index than that of the first cladding, and a third cladding which becomes a glass region substantially noncontributory to propagation of signal light. In particular, the third cladding contains a desired impurity such that the glass viscosity thereof becomes lower than that of the second cladding or pure silica cladding at a predetermined temperature.

Abstract: In a method of fabricating DCF, the fiber is drawn while rotating said optical fiber preform, wherein a rotational speed of said optical fiber preform is 10 to 1,000 rpm, a drawing speed is 50 to 1,000 m/min, and a drawing tension is 2.4 to 13 kg/mm.sup.2.