Abstract:
It is provided a structure capable of reducing the loss of incident light propagating in a three-dimensional optical waveguide in a optical waveguide substrate having a ridge type optical waveguide. An optical waveguide substrate has a ferroelectric layer 3 made of a ferroelectric material, a ridge portion formed on a surface of the layer 3 and protrusions provided in both sides of the ridge portion. A three-dimensional optical waveguide is provided in the ridge portion. Alternatively, the substrate has a ridge portion 15 formed on a surface of the layer 3 and step portions provided in both sides of the ridge portion 15 and lower than the ridge portion 15. Grooves 16 are formed in the outsides of the step portions, respectively, and a three-dimensional optical waveguide is provided in the ridge portion 15.
Abstract:
A hybrid MOS optical modulator. The optical modulator includes an optical waveguide, a cathode comprising a first material and formed in the optical waveguide, and an anode comprising a second material dissimilar from the first material and formed in the optical waveguide, the anode adjoining the cathode, a capacitor being defined between the anode and the cathode.
Abstract:
The optical device includes a waveguide on a base. The device also includes a modulator on the base. The modulator includes an electro-absorption medium configured to receive a light signal from the waveguide. The modulator also includes field sources for generating an electrical field in the electro-absorption medium. The electro-absorption medium is a medium in which the Franz-Keldysh effect occurs in response to the formation of the electrical field in the electro-absorption medium. The field sources are configured so the electrical field is substantially parallel to the base.
Abstract:
An optical waveguide (1) is formed on a substrate (2) and includes a curved ridge structure (3), a curved optical path, and a buffer layer. The curved ridge structure is formed on the substrate so as to have a curvature in a longitudinal direction of the curved ridge structure. The curved optical path is formed along the curved ridge structure. The buffer layer (4) covers a side of the ridge structure and has a lower refractive index than a refractive index of the substrate.
Abstract:
An optically controlled grating switch has at least one switch region (13) for ON-OFF switch control of a signal light transmission and a signal light reflection, at least one input/output optical waveguide region (14) for guiding the signal light to the switch, at least one coupler region (15) for coupling the control light colinearly to the signal light and for guiding the control light to the switch region (13) together with the signal light, and at least one separator region (16) for separating the signal light and the control light. The switch region (13) transmits the signal light when the control light is coupled while reflects the signal light when the control light is not coupled.
Abstract:
A semiconductor optical guided-wave device comprises a semiconductor substrate (101), at least one ridge type semiconductor optical waveguide formed thereon, and a pair of electrodes (108,110). The ridge (131) is formed by a selective crystal growth process. The ridge can be formed using a mask (201) having an opening (202) where the ridge is to be formed, and the crystal growth of material for forming the ridge is made by a crystal growth technology such as the MOVPE method. The mask is preferably a thin dielectric film, such as SiO₂ film. The device comprises grown layers including a first semiconductor cladding layer (102), a semiconductor guiding layer (103) and a second semiconductor cladding layer (104) grown in this order, and a ridge (131) having a third semiconductor cladding layer (105) and a semiconductor capping layer (106) laminated in this order on the second semiconductor cladding layer. The device can be formed as an optical phase modulator a directional coupler or a Mach-Zehnder type optical modulator. The device can be small with low power loss, and suitable for large-scale integration and mass production.
Abstract in simplified Chinese:本发明涉及一种电光调制器,其包括:基底、嵴型光波导结构、第一地电极、第一调制电极、第二地电极与第二调制电极;该嵴型光波导结构位于该基底的顶面,该嵴型光波导结构包括嵴型结构及形成在嵴型结构中的光波导,该嵴型结构包括Y型分岔部,该分岔部包括第一分支以及第二分支;该第一分支包括第一子Y型光波导,该第一子Y型光波导包括第一子分支与第二子分支;该第二分支包括第二子Y型光波导,该第二子Y型光波导包括第三子分支及第四子分支;该第一地电极与该第一调制电极用于调制该第一子Y型光波导;第二地电极与第二调制电极用于调制该第二子Y型光波导;以使该第一子Y型光波导及该第二子Y型光波导输出的功率相同,从而提高消光比。