FUJITSU OPTICAL COMPONENTS LIMITED

An optical integrated circuit module includes an optical integrated circuit element that includes as optical waveguide that is made by using an organic electro-optical material, and a cover that seals, as vacuum sealing, at least the optical waveguide that is disposed on the optical integrated circuit element. In addition, the optical integrated circuit module includes an oxygen getter that is provided in an inner part of the cover and that absorbs oxygen contained in the inner part of the cover.

An optical device includes a substrate, a tapered waveguide that is arranged in a first layer on the substrate and that has a waveguide width that gradually increases from input to output, a rib waveguide that is arranged in a second layer on the substrate, where the second layer is different from the first layer, and overlaps with the tapered waveguide in a plane direction. The rib waveguide includes a rib that has a core width that gradually increases from the input to the output, and slabs that are arranged on both sides of the rib and that have slab widths that gradually increase from the input to the output.

An optical device includes a substrate, an optical waveguide, and a first chip and a second chip each of which is mounted on the substrate, includes a material having an electro-optical effect that is higher than that of the substrate, and includes a crystal axis in which the strongest electro-optical effect is exerted. The first chip includes a first electrode that is arranged in the vicinity of an input side first waveguide, and that applies an electric field flowing in the same direction as an orientation of the crystal axis of the first chip to the input side first waveguide. The second chip includes a second electrode that is arranged in the vicinity of an output side first waveguide, and that applies an electric field flowing in the same direction as an orientation of the crystal axis of the second chip to the output side first waveguide.

An optical device includes a transition unit in which a first waveguide and a second waveguide are disposed in an overlapped manner such that a magnitude relationship of an effective refractive index between the vertical modes propagating the first waveguide and the vertical modes propagating the second waveguide is inverted at the positions of input and output. The transition unit allows, at the input, the second waveguide to be a single mode waveguide and allows, at the output, the second waveguide to be a multi-mode waveguide through which TM0 light in the maximum vertical mode and light in a higher-order mode propagate. The optical device includes a removing unit that allows the second waveguide to be a single mode waveguide through which the TM0 light propagates by removing the light in the higher-order mode from the light received from the transition unit.

An optical device includes a first coupler, a second coupler, and a monitor. The first coupler includes a first input port, a first bar port, and a first cross port, and largely taps signal light on a short wavelength side from the first input port to the first bar port. The second coupler includes a second input port, a second bar port, and a second cross port, and largely taps signal light on a long wavelength side from the second input port to the second cross port. The monitor is connected to one of the first bar port and the second cross port, and monitors signal light that is output from one of the first bar port and the second cross port.

An optical device includes a channel waveguide that has a waveguide width that increases in a tapered manner, and a rib waveguide that is connected to a side at which the waveguide width of the channel waveguide is increased and that includes a rib portion and slab portions. The rib waveguide includes a tapered waveguide in which a rib width of the rib portion increases in a tapered manner with distance from a part at a side at which the channel waveguide is connected.

An optical integrated device includes a first chip having a step portion, and a second chip that is mounted on the step portion, and that is optically connected to the first chip. The first chip includes an optical waveguide including a material having a high electro-optic effect compared to a material of the second chip. The optical integrated device includes a first inclined surface that is formed on a wall surface on a side on which the optical waveguide and the second chip are optically connected in the step portion, and a second inclined surface that is formed on an end surface of the second chip on a side on which it is mounted within the step portion, and that abuts on the first inclined surface facing the first inclined surface.

An optical device includes a rib optical waveguide including N parallel waveguides connected to outputs of a split coupler of 1 input×N outputs, and a first electrode and a second electrode that are connected to the rib optical waveguide. The rib optical waveguide includes a non-conductive slab region formed between the waveguides, a P-doped region and an N-doped region. The P-doped region is formed in a first slab region outside one of outermost waveguides of the N waveguides and is connected to the first electrode. The N-doped region is formed in a second slab region outside the other one of the outermost waveguides of the N waveguides and is connected to the second electrode.

An optical module includes an optical transmitter that outputs transmission light to a transmission path port by using an optical signal, and an optical receiver that receives reception light received from the transmission path port by using the optical signal. The optical module includes an optical fiber that is a single mode optical fiber (SMF), that connects the optical transmitter and the optical receiver to the transmission path port, and through which the optical signal propagates. The wavelength of the optical signal is equal to or less than a cutoff wavelength of the optical fiber. The optical module incudes a holding mechanism that holds a bending shape of the optical fiber having a predetermined radius of curvature and through which only a basic mode included in the optical signal propagates.

A disclosed semiconductor photodetector includes a first semiconductor layer having a first refractive index and a first band gap; a second semiconductor layer formed on the first semiconductor layer, the second semiconductor layer having a second refractive index and a second band gap; a first electrode; and a second electrode. The second refractive index is greater than the first refractive index, and the second band gap is smaller than the first band gap. The first semiconductor layer includes a p-type first region, an n-type second region, and a non-conductive third region between the first region and the second region. The second semiconductor layer includes a p-type fourth region in ohmic contact with the first electrode, an n-type fifth region in ohmic contact with the second electrode, and a non-conductive sixth region between the fourth region and the fifth region.