摘要:
An optical functional device comprises a dielectric substrate 5, a ferroelectric thin layer 10 provided on the dielectric substrate 5 and comprising a material having electro-optical effect and an electrode 3A, 3B provided on the ferroelectric thin layer 10. A part of the ferroelectric thin layer 10 functions as a core 9 of the optical wave guide and the dielectric substrate functions as a clad for the optical waveguide. The optical waveguide 9 constitutes a multi-mode waveguide in the direction “D” of depth of the ferroelectric thin layer.
摘要:
A voltage is applied on a first branch 3a by a first ground electrode 10 and a signal electrode 11, and a voltage is applied on a second branch 3b by a second ground electrode 12A and the signal electrode 11. A first gap 13 is formed between the first ground electrode 10 and the signal electrode 11, and a second gap 14 is formed between the second ground electrode 12A and the signal electrode 11. The first gap 13 and the second gap 14 are divided into voltage applying portions 13a, 14a, feed-through portions and connection portions 13b, 14b therebetween, respectively, and satisfy the formula: G12/G11≦G22/G21
摘要翻译:第一接地电极10和信号电极11对第一分支3a施加电压,并且通过第二接地电极12A和信号电极11将电压施加在第二分支3b上。第一间隙13 形成在第一接地电极10和信号电极11之间,并且在第二接地电极12A和信号电极11之间形成第二间隙14.第一间隙13和第二间隙14被分成电压施加部分13 a,14a,馈通部分和连接部分13b,14b,分别满足下列公式:G 12 / G 11 <= G 21 SUB>表示连接部分侧的端部13c处的第一间隙13的宽度,G 22表示在第二间隙14的端部14c处的第二间隙14的宽度 连接部分侧面14c,G31表示电压施加部分13a处的第一间隙13的宽度,G 32表示第二间隙14的宽度 电压施加部分14a。
摘要:
A Mach-Zehnder optical waveguide is disposed in a substrate made of a material having an electro-optic effect. Coplanar-waveguide modulating electrodes are disposed on a principal surface of the substrate. A dielectric layer is disposed on a reverse surface of the substrate. A supporting substrate having a recess is disposed in contact with the dielectric layer such that the recess is located at a position corresponding to a modulating region. The relationship: ∈r>∈s is satisfied where ∈r represents the dielectric constant of the supporting substrate and ∈s represents the dielectric constant of the dielectric constant of solid, liquid, or gaseous substance in the recess.
摘要:
An optical waveguide device 1A has a substrate 22 and a supporting body 10 for supporting the substrate. The substrate 22 has a main body 2 made of an electrooptic material and one and the other main faces, optical waveguides 3a, 3b and electrodes 4B, 4C provided on the side of the one main face 2a of the main body 2 The supporting body 10 is joined with the substrate 2 on the side of the other main face, and the electrode has a feedthrough portion. The device 1A further has a low dielectric portion 7 provided under the feed through portion and between the other main face 2b of the main body 2 and the supporting body 10.
摘要:
A device 4 has a substrate 5, an optical waveguide 2 and modulation electrodes 1A, 1B, 1C. The substrate 5 is made of an electro-optic material and has a thickness of ≦30 μm at least in a region where the modulation electrode applies an electric field. The device has a ridge generated when the optical waveguide is formed, and the ridge has a height H (angstrom) and a width “W” (μm) whose product (H×W) is 7150 angstrom·μm or smaller to realize single mode propagation of light in the optical waveguide. The wave guide has branched parts in the region where the modulation electrode applied an electric field. The deviation of positions of peaks and bottoms in the extinction ratio curve can be reduced, by increasing the distance of the branched parts of the optical waveguide to ≧46 μm.
摘要:
A voltage is applied on a first branch 3a by a first ground electrode 10 and a signal electrode 11, and a voltage is applied on a second branch 3b by a second ground electrode 12A and the signal electrode 11. A first gap 13 is formed between the first ground electrode 10 and the signal electrode 11, and a second gap 14 is formed between the second ground electrode 12A and the signal electrode 11. The first gap 13 and the second gap 14 are divided into voltage applying portions 13a, 14a, feed-through portions and connection portions 13b, 14b therebetween, respectively, and satisfy the formula: G12/G11≦G22/G21
摘要翻译:第一接地电极10和信号电极11对第一分支3a施加电压,并且通过第二接地电极12A和信号电极11将电压施加在第二分支3b上。第一间隙13 形成在第一接地电极10和信号电极11之间,并且在第二接地电极12A和信号电极11之间形成第二间隙14.第一间隙13和第二间隙14被分成电压施加部分13 a,14a,馈通部分和连接部分13b,14b,分别满足下列公式:G 12 / G 11 <= G 21 SUB>表示连接部分侧的端部13c处的第一间隙13的宽度,G 22表示在第二间隙14的端部14c处的第二间隙14的宽度 连接部分侧面14c,G31表示电压施加部分13a处的第一间隙13的宽度,G 32表示第二间隙14的宽度 电压施加部分14a。
摘要:
An object of the present invention is to improve the modulation efficiency of an optical modulator in a high frequency band while satisfying the velocity matching condition. An optical modulator is provided having an optical waveguide for propagating light, an electrode for applying a voltage on the waveguide for modulating the light, a signal source electrically connected to the electrode and a terminating resistance electrically connected to the electrode. The signal source has a characteristic impedance Zi and the terminating resistance has an impedance Zl satisfying the formula (Zi
摘要:
A travelling wave-type optical modulator has a supporting substrate and a ferroelectric single crystalline layer on the supporting substrate. The ferroelectric single crystalline layer has thicker parts and thinner parts within the modulating region of the travelling wave-type optical modulator when viewed in the cross section of the modulating region. An optical waveguide is formed in the thicker part of the ferroelectric single crystalline layer, and electrodes for modulation are provided on the thinner part of the ferroelectric single crystalline layer between the adjacent thicker parts.
摘要:
A travelling wave-type optical modulator has a substrate made of an electro-optic material, optical waveguides fabricated on the top surface of the substrate, and electrodes for modulating an optical wave through the optical waveguide. The substrate is partially thinned from the bottom surface of the substrate to form a first thinned portion and a second thinned portion so that the thickness of the first thinned portion is set to be larger than the thickness of the second thinned portion, and the optical waveguide is positioned in the first thinned portion.
摘要:
An optical waveguide device has an optical waveguide substrate and a supporting body for supporting the substrate. The substrate has a main body made of an electro-optic material and having a main face and an opposing face, optical waveguides, and electrodes for applying an electrical signal on the optical waveguides. At least a part of the opposing face of the supporting body opposing the substrate is covered with a conductive layer. It is thus possible to reduce the resonance due to substrate radiation leakage of the microwave signal into the whole of the optical waveguide substrate and supporting body.