摘要:
An optical module is provided for performing a prescribed function such as dispersion compensation, for example. The optical module is to be integrated between stages of a multi-stage rare-earth doped optical amplifier. The module includes an input port for receiving optical energy from one stage of the rare-earth doped optical amplifier and a rare-earth doped planar waveguide coupled to the input port. An optically lossy, passive element is provided for performing the prescribed function. The optically lossy, passive element is coupled to the planar waveguide for receiving optical energy therefrom. An output port is coupled to the optically lossy, passive element for providing optical energy to another stage of the rare-earth doped optical amplifier. The rare-earth doped planar waveguide has a first unsaturated absorption spectrum and the rare-earth doped optical amplifier has a second unsaturated absorption spectrum such that the ratio of the first to the second absorption spectrum is substantially wavelength independent within the spectral range of incoming and outgoing optical energy. The rare-earth doped planar waveguide has a length determined at least in part from a value of optical loss in the passive element and characteristics of the rare-earth doped optical amplifier.
摘要:
A multistage optical amplifier includes a fiber amplifier stage having an active optical fiber for imparting gain to an optical signal propagating therethrough and a coupler supplying pump energy to the optical fiber. A planar waveguide amplifier stage is optically coupled to the fiber amplifier stage. The waveguide amplifier including a substrate, an active planar waveguide formed on the substrate for imparting gain to an optical signal propagating therethrough, and at least one waveguide coupler formed on the substrate for coupling pump power to the active planar waveguide.
摘要:
An apparatus is provided to compensate for dispersion in a transmission medium. The apparatus includes an input port for receiving a WDM optical signal having a plurality of signal wavelengths and a first Bragg transmission grating receiving the WDM optical signal from the input port. The first Bragg transmission grating has non-zero dispersion at at least one of the signal wavelengths. The first Bragg transmission grating also has a Bragg wavelength that is chosen so that all of the plurality of signal wavelengths lie outside of a reflection band of the first Bragg transmission grating. A second Bragg transmission grating, which is optically coupled to the first Bragg transmission grating, has a non-zero dispersion at at least one of the signal wavelengths. The second Bragg transmission grating also has a Bragg wavelength that is selected so that all of the plurality of signal wavelengths lie outside of a reflection band of the second Bragg transmission grating. Finally, an output port is provided for receiving the optical signal from the second Bragg grating and communicating the optical signal to an external source.
摘要:
A method is provided for converting optical energy to electrical energy in a spectrally adaptive manner. The method begins by directing optical energy into a first photovoltaic module that includes non-single crystalline semiconductor layers defining a junction such that a first spectral portion of the optical energy is converted into a first quantity of electrical energy. A second spectral portion of the optical energy unabsorbed by the first module is absorbed by a second photovoltaic module that includes non-single crystalline semiconductor layers defining a junction and converted into a second quantity of electrical energy. The first quantity of electrical energy is conducted from the first module to a first external electrical circuit along a first path. The second quantity of electrical energy is conducted from the second module to a second external electrical circuit along a second path that is in parallel with the first path.
摘要:
A method is provided for converting optical energy to electrical energy in a spectrally adaptive manner. The method begins by directing optical energy into a first photovoltaic module that includes non-single crystalline semiconductor layers defining a junction such that a first spectral portion of the optical energy is converted into a first quantity of electrical energy. A second spectral portion of the optical energy unabsorbed by the first module is absorbed by a second photovoltaic module that includes non-single crystalline semiconductor layers defining a junction and converted into a second quantity of electrical energy. The first quantity of electrical energy is conducted from the first module to a first external electrical circuit along a first path. The second quantity of electrical energy is conducted from the second module to a second external electrical circuit along a second path that is in parallel with the first path.
摘要:
A method for producing a film of compound semiconductor includes providing a substrate and a compound bulk material having a first chemical composition that includes at least one first chemical element and a second chemical element. A film is deposited on the substrate using the compound bulk material as a single source of material. The deposited film has a composition substantially the same as the first chemical composition. A residual chemical reaction is induced in the deposited film using a source containing the second chemical element to thereby increase the content of the second chemical element in the deposited film so that the deposited film has a second chemical composition. The film may be employed in a photovoltaic device.
摘要:
A semiconductor laser source includes a laser diode having front and rear facets. The laser diode includes a substrate and a lower cladding layer disposed on the substrate. The lower cladding layer is doped with a dopant of the first conductivity type. An active layer is disposed on the lower cladding layer and an upper cladding layer is disposed on the active layer. The upper cladding layer is doped with a dopant of the second conductivity type. At least one electrode is disposed on a first outer layer of the diode. A pair of electrodes is disposed on a second outer layer of the diode. The second outer layer is located on a side of the diode opposing the first outer layer. The pair of electrodes is configured to allow application of different currents to each one of the electrodes in the pair of electrodes. A reflector, which is located external to the laser diode, is in optical communication with the front facet of the laser diode for providing optical feedback to the active region.
摘要:
An integrated optical device is provided for distributing optical pump energy. The device includes at least one input port for receiving optical energy, a plurality of output ports, and a user configurable optical network coupled to the input port for distributing the optical energy among the output ports in a prescribed manner in conformance with a user-selected configuration.
摘要:
A planar waveguide optical amplifier includes a substrate and an active waveguide formed on the substrate for imparting gain to an optical signal propagating therethrough. The active waveguide has an input port for receiving an optical signal to be amplified and an output port on which an amplified optical signal is directed. A plurality of coupling elements are formed on the substrate and are adapted to couple pump power to the active waveguide. The plurality of coupling elements are located at predetermined positions along the active waveguide.
摘要:
A photovoltaic device includes a plurality of photovoltaic cells disposed in an array in which each cell is adjacent to another cell. Each of the cells includes first and second photovoltaic modules. The first photovoltaic module of each cell is configured to convert a first part of light energy incident thereon into electrical energy and to reflect to the second photovoltaic module of an adjacent cell at least some of a remaining portion of light energy incident thereon. The second photovoltaic module of each cell is configured to convert into electrical energy the remaining portion of the light energy received from the first photovoltaic module of an adjacent cell.