117results about How to "Modulation speed" patented technology

A method for producing a high frequency optical signal component representative of a high frequency electrical input signal component, includes the following steps: providing a semiconductor transistor structure that includes a base region of a first semiconductor type between semiconductor emitter and collector regions of a second semiconductor type; providing, in the base region, at least one region exhibiting quantum size effects; providing emitter, base, and collector electrodes respectively coupled with the emitter, base, and collector regions; applying electrical signals, including the high frequency electrical signal component, with respect to the emitter, base, and collector electrodes to produce output spontaneous light emission from the base region, aided by the quantum size region, the output spontaneous light emission including the high frequency optical signal component representative of the high frequency electrical signal component; providing an optical cavity for the light emission in the region between the base and emitter electrodes; and scaling the lateral dimensions of the optical cavity to control the speed of light emission response to the high frequency electrical signal component.

This optical modulator includes a substrate and a phase modulation unit on the substrate, said phase modulation unit including: a first traveling-wave electrode, a second traveling-wave electrode, and an optical waveguide configured from a first cladding layer, a semiconductor layer, which is laminated on the first cladding layer, and has a refractive index that is higher than that of the first cladding layer, and a second cladding layer, which is laminated on the semiconductor layer, and has a refractive index that is lower than that of the semiconductor layer. The semiconductor layer is provided with: a rib section, which is formed in the optical axis direction of the optical waveguide, and is to be the core of the optical waveguide; a first slab section formed in the optical axis direction on one side of the rib section; a second slab section formed in the optical axis direction on the other side of the rib section; a third slab section formed in the optical axis direction on the first slab section side opposite to the rib section; and a fourth slab section formed in the optical axis direction on the second slab section side opposite to the rib section. The first slab section is formed thinner than the rib section and the third slab section, and the second slab section is formed thinner than the rib section and the fourth slab section.

The invention discloses a vertical cavity surface emitting laser comprising a substrate on which a base substrate, a bottom n-type DBR mirror, a first oxidation limiting layer, an n-type guiding spacer layer, an active region layer, a p-type gradual change spacer layer, a second oxidation limiting layer, a first spacer layer, a third oxidation limiting layer, a second spacer layer, a fourth oxidation limiting layer, a third spacer layer, a fifth oxidation limiting layer, a fourth spacer layer, a six oxidation limiting layer, a fifth spacer layer, a seventh oxidation limiting layer, a sixth spacer layer, an eighth oxidation limiting layer, a top p-type DBR mirror, a p-type contact layer, and a p-side electrode are successively disposed. An n-side electrode is disposed on a side of the substrate away from the base substrate. The vertical cavity surface emitting laser can stably achieve single-mode operation, is low in optical loss, low in power consumption and low in parasitic capacitance.

The present invention relates to optical filter, and is especially one kind adjustable multilayer film filter for long distance communication. The adjustable film filter includes one film waveguide and one peripheral unit around the film waveguide. Compressing or stretching the peripheral unit to apply some force onto the film waveguide can regulate the central wavelength of the adjustable film filter. The present invention also provides one kind of optical system with the adjustable film filter. The present invention solves the problem that the optical filter can transmit incident light one fixed central wavelength only.