Abstract: An optical switch, an optical modulator, and a wavelength variable filter each have a simple configuration, which requires only a low driving voltage, which is independent of polarization, and which can operate at high speed. An optical switch includes a 3-dB coupler placed on an output, a 3-dB coupler placed on an output, and two optical waveguides connecting the input-side 3-dB coupler and the output-side 3-dB coupler together. The optical switch also includes a phase modulating section that applies electric fields to one or both of the two optical waveguides. At least two optical waveguides are a crystal material including KTaxNb1-xO3 (0<x<1) and KxLi1-xTayNb1-yO3 (0<x<1, 0<y<1), or KTaxNb1-xO3 or KxLi1-xTayNb1-yO3.

Abstract: A plasma display panel of the present invention includes a display electrode 102 and an address electrode 112 as well as a dielectric layer (a dielectric layer 106 and/or a dielectric layer 113) that is formed on at least one electrode selected from the group consisting of the display electrode 102 and the address electrode 112. The at least one dielectric layer includes glass having the following composition, as its main constituent element: 0 to 15 wt % SiO2; 10 to 50 wt % B203; 26 to 50 wt % ZnO; 0 to 10 wt % Al2O3; 2 to 30 wt % Bi2O3; 0 to 0.1 wt % PbO; and 5 to 38 wt % RO, where RO denotes at least one oxide selected from the group consisting of CaO, SrO, and BaO.

Abstract: An optical switch, an optical modulator, and a wavelength variable filter each have a simple configuration, which requires only a low driving voltage, which is independent of polarization, and which can operate at high speed. An optical switch includes a 3-dB coupler placed on an output, a 3-dB coupler placed on an output, and two optical waveguides connecting the input-side 3-dB coupler and the output-side 3-dB coupler together. The optical switch also includes a phase modulating section that applies electric fields to one or both of the two optical waveguides. At least two optical waveguides are a crystal material including KTaxNb1-xO3 (0<x<1) and KxLi1-xTayNb1-xO3 (0<x<1, 0<y<1), or KTaxNb1-xO3 or KxLi1-xTayNb1-yO3.

Abstract: A glass composition for covering electrodes of the present invention contains: 0 to 15 wt % SiO2; 10 to 50 wt % B2O3; 15 to 50 wt % ZnO; 0 to 10 wt % Al2O3; 2 to 40 wt % Bi2O3; 0 to 5 wt % MgO; 5 to 38 wt % CaO+SrO+BaO; 0 to 0.1 wt % Li2O+Na2O+K2O; 0 to 4 wt % MoO3; and 0 to 4 wt % WO3, and the total of the contents of MoO3 and WO3 is in the range of 0.1 to 8 wt %. The glass composition for covering electrodes of the present invention may contain: 0 to 2 wt % SiO2; 10 to 50 wt % B2O3; 15 to 50 wt % ZnO; 0 to 10 wt % Al2O3; 2 to 40 wt % Bi2O3; 0 to 5 wt % MgO; 5 to 38 wt % CaO+SrO+BaO; 0 to 4 wt % MoO3; and 0 to 4 wt % WO3, and the total of the contents of MoO3 and WO3 may be in the range of 0.1 to 8 wt %.

Abstract: An optical switch, an optical modulator, and a wavelength variable filter each have a simple configuration, which requires only a low driving voltage, which is independent of polarization, and which can operate at high speed. An optical switch includes a 3-dB coupler placed on an output, a 3-dB coupler placed on an output, and two optical waveguides connecting the input-side 3-dB coupler and the output-side 3-dB coupler together. The optical switch also includes a phase modulating section that applies electric fields to one or both of the two optical waveguides. At least two optical waveguides are a crystal material including KTaxNb1-xO3 (0<x<1) and KxLi1-xTayNb1-yO3 (0<x<2, 0<y<1), or KTaxNb1-xO3 or KxLi1-xTayNb1-yO3.

Abstract: The present invention provides an optical switch, an optical modulator, and a wavelength variable filter each of which has a simple configuration, which requires only a low driving voltage, which is independent of polarization, and which can operate at high speed. An optical switch according to the present invention includes a 3-dB coupler (16) placed on an output, a 3-dB coupler (17) placed on an output, and two optical waveguides connecting the input-side 3-dB coupler and the output-side 3-dB coupler together. The optical switch also includes a phase modulating section (18) that applies electric fields to one or both of the two optical waveguides. At least two optical waveguides are a crystal material including KTaxNb1-xO3 (0<x<1) and KxLi1-xTayNb1-yO3 (0<x<1, 0<y<1), or KTaxNb1-xO3 or KxLi1-xTayNb1-yO3.

Abstract: A plasma display panel of the present invention includes display electrodes and address electrodes that cross each other. The electrode to be covered with the first dielectric layer contains at least one selected from silver and copper. The first glass contains Bi2O3. The first glass further contains 0 to 4 wt % of MoO3 and 0 to 4 wt % of WO3, and the total of the contents of MoO3 and WO3 that are contained in the first glass is in a range of 0.1 to 8 wt %. The first glass may contain, as components thereof: 0 to 15 wt % SiO2; 10 to 50 wt % B2O3; 15 to 50 wt % ZnO; 0 to 10 wt % Al2O3; 2 to 40 wt % Bi2O3; 0 to 5 wt % MgO; 5 to 38 wt % CaO+SrO+BaO; 0 to 4 wt % MoO3; and 0 to 4 wt % WO3, and the total of the contents of MoO3 and WO3 that are contained in the first glass is in the range of 0.1 to 8 wt %.

Abstract: The invention provides an optical waveguide material whose refractive index can be tailored without changing the ratio of Ta and Nb. An optical waveguide of this invention comprising an under-clad layer 1 and a core 2 that is formed on the under-clad layer 1 and has a higher refractive index than that of the under-clad layer 1 is shown. For example, KTN (KTa1?xNbxO3) is used as the core 2, and a material that is obtained by substituting at least one element selected from the group consisting of Zr, Hf, and Sn for a portion of one element of the constituent elements of KTN and has the same perovskite type crystal structure as KTN is used as the clad. The refractive index of KTN can be reduced considerably, and this controllability widens the degree of freedom in the design of optical waveguide devices.

Abstract: A glass composition for covering electrodes of the present invention contains: 0 to 15 wt % SiO2; 10 to 50 wt % B2O3; 15 to 50 wt % ZnO; 0 to 10 wt % Al2O3; 2 to 40 wt % Bi2O3; 0 to 5 wt % MgO; 5 to 38 wt % CaO+SrO+BaO; 0 to 0.1 wt % Li2O+Na2O+K2O; 0 to 4 wt % MoO3; and 0 to 4 wt % WO3, and the total of the contents of MoO3 and WO3 is in the range of 0.1 to 8 wt %. The glass composition for covering electrodes of the present invention may contain: 0 to 2 wt % SiO2; 10 to 50 wt % B2O3; 15 to 50 wt % ZnO; 0 to 10 wt % Al2O3; 2 to 40 wt % Bi2O3; 0 to 5 wt % MgO; 5 to 38 wt % CaO+SrO+BaO; 0 to 4 wt % MoO3; and 0 to 4 wt % WO3, and the total of the contents of MoO3 and WO3 may be in the range of 0.1 to 8 wt %.

Abstract: A wavelength tunable optical filter (1) comprises a dielectric crystal portion (2) comprised of a dielectric crystal having a cubic system and exhibiting a quadratic electro-optic effect, a mirror portion (5, 6) constituting a Fabry-Perot etalon in cooperation with said dielectric crystal portion, and an electrode (3, 4) configured to apply a voltage to said dielectric crystal portion thereby to change a wavelength of light transmitting through said etalon on a basis of said electro-optic effect. According to the configuration, since the dielectric crystal having a cubic system and exhibiting a quadratic electro-optic effect is used, there is provided a wavelength tunable optical filter that is capable of operating at high-speed on application of a low voltage.

Abstract: The invention provides an optical waveguide material whose refractive index can be tailored without changing the ratio of Ta and Nb. An optical waveguide of this invention comprising an under-clad layer 1 and a core 2 that is formed on the under-clad layer 1 and has a higher refractive index than that of the under-clad layer 1 is shown. For example, KTN (KTa1?xNbxO3) is used as the core 2, and a material that is obtained by substituting at least one element selected from the group consisting of Zr, Hf, and Sn for a portion of one element of the constituent elements of KTN and has the same perovskite type crystal structure as KTN is used as the clad. The refractive index of KTN can be reduced considerably, and this controlability widens the degree of freedom in the design of optical waveguide devices.

Abstract: An optical waveguide capable of having various characteristics and a method of manufacture thereof as well as a method of manufacturing a crystal film are provided. An optical functional material KTaxNb1?xO3 is used as an optical waveguide. The input optical signal is transmitted to the KTaxNb1?xO3 film. The KTaxNb1?xO3 film undergoes changes in optical property when an external voltage signal is applied to the electrode. Therefore, as it passes through the KTaxNb1?xO3 film, the input optical signal is modulated by the characteristic change. The modulated optical signal is taken out as an output optical signal.

Abstract: The present invention relates to an electric field sensor including: a light source (1); an electro optic crystal (7) which is applied with an electric field based on a signal under test, in which a birefringent index changes according to the electric field, and which changes a polarization state of light incident from the light source according to the birefringent index and emits the light; and a detector (9, 17, 19, 21) that detects an electric signal according to the change of the polarization state of the light emitted from the electro optic crystal (7). Further, the electric field sensor includes: a signal electrode (11) for applying the electric field based on the signal under test to the electro optic crystal (7); a counter electrode (12) that forms a pair with the signal electrode (11); and an auxiliary electrode (61) that is electrically connected to the counter electrode (12), and that forms a capacitance with ground.

Abstract: The invention provides an optical waveguide material whose refractive index can be tailored without changing the ratio of Ta and Nb. An optical waveguide of this invention comprising an under-clad layer 1 and a core 2 that is formed on the under-clad layer 1 and has a higher refractive index than that of the under-clad layer 1 is shown. For example, KTN (KTa1?xNbxO3) is used as the core 2, and a material that is obtained by substituting at least one element selected from the group consisting of Zr, Hf, and Sn for a portion of one element of the constituent elements of KTN and has the same perovskite type crystal structure as KTN is used as the clad. The refractive index of KTN can be reduced considerably, and this controllability widens the degree of freedom in the design of optical waveguide devices.

Abstract: An optical waveguide capable of having various characteristics and a method of manufacture thereof as well as a method of manufacturing a crystal film are provided. An optical functional material KTaxNb1-xO3 is used as an optical waveguide. The input optical signal is transmitted to the KTaxNb1-xO3 film. The KTaxNb1-xO3 film undergoes changes in optical property when an external voltage signal is applied to the electrode. Therefore, as it passes through the KTaxNb1-xO3 film, the input optical signal is modulated by the characteristic change. The modulated optical signal is taken out as an output optical signal.

Abstract: An optical waveguide capable of having various characteristics and a method of manufacture thereof as well as a method of manufacturing a crystal film are provided. An optical functional material KTaxNb1-xO3 is used as an optical waveguide. The input optical signal is transmitted to the KTaxNb1-xO3 film. The KTaxNb1-xO3 film undergoes changes in optical property when an external voltage signal-is applied to the electrode. Therefore, as it passes through the KTaxNb1-xO3 film, the input optical signal is modulated by the characteristic change. The modulated optical signal is taken out as an output optical signal.

Abstract: An optical waveguide capable of having various characteristics and a method of manufacture thereof as well as a method of manufacturing a crystal film are provided. An optical functional material KTaxNb1-xO3 is used as an optical waveguide. The input optical signal is transmitted to the KTaxNb1-xO3 film. The KTaxNb1-xO3 film undergoes changes in optical property when an external voltage signal is applied to the electrode. Therefore, as it passes through the KTaxNb1-xO3 film, the input optical signal is modulated by the characteristic change. The modulated optical signal is taken out as an output optical signal.

Abstract: A photosensitive composition for optical waveguides comprising of an organic oligomer, a polymerization initiator and a crosslinking agent, the organic oligomer being a silicone oligomer represented by the following formula (1), wherein X denotes hydrogen, deuterium, halogen, an alkyl group or an alkoxy group; m is an integer from 1 to 5; x and y represent the proportion of respective units, and neither x nor y is 0; and R1 denotes a methyl, ethyl, or isopropyl group; a production method thereof, and a polymer optical waveguide pattern formation method using the same.

Abstract: An optical waveguide capable of having various characteristics and a method of manufacture thereof as well as a method of manufacturing a crystal film are provided. An optical functional material KTaxNb1-xO3 is used as an optical waveguide. The input optical signal is transmitted to the KTaxNb1-xO3 film. The KTaxNb1-xO3 film undergoes changes in optical property when an external voltage signal is applied to the electrode. Therefore, as it passes through the KTaxNb1-xO3 film, the input optical signal is modulated by the characteristic change. The modulated optical signal is taken out as an output optical signal.

Abstract: A photosensitive composition for optical waveguides comprising of an organic oligomer, a polymerization initiator and a crosslinking agent, the organic oligomer being a silicone oligomer represented by the following formula (1), wherein X denotes hydrogen, deuterium, halogen, an alkyl group or an alkoxy group; m is an integer from 1 to 5; x and y represent the proportion of respective units, and neither x nor y is 0; and R1 denotes a methyl, ethyl, or isopropyl group; a production method thereof, and a polymer optical waveguide pattern formation method using the same.