98 results about "Superluminescent diode" patented technology

An optoelectronic device, comprising an active region and a waveguide structure to provide optical confinement of light emitted from the active region; a pair of facets on opposite ends of the device, having opposite surface polarity; and one of the facets which has been roughened by a crystallographic chemical etching process, wherein the device is a nonpolar or semipolar (Ga,In,Al,B)N based device.

A method for detecting tooth decay and other tooth anomalies wherein a tooth is transilluminated with a near-infrared light source preferably in the range from approximately 795-nm to approximately 1600-nm, more preferably in the range from approximately 830-nm to approximately 1550-nm, more preferably in the range from approximately 1285-nm to approximately 1335-nm, and more preferably at a wavelength of approximately 1310-nm, and the light passing through the tooth is imaged for determining an area of decay in the tooth. The light source is a fiber-optic bundle coupled to a halogen lamp or more preferably a superluminescent diode, and the imaging device is preferably a CCD camera or a focal plane array (FPA).

An optical interrogation system 10 includes optical amplifying and gating apparatus, in the form of a semiconductor optical amplifier (SOA) 14 and an optical source 12, 14. Drive apparatus 22 (an electrical pulse generator driven by a variable frequency oscillator) is provided to generate electrical drive pulses (see inset (a)) which are applied to the SOA 14, to cause the SOA 14 to switch on and off. The optical source comprises a super-luminescent diode (SLD) 12, the CW output from which is gated into optical pulses by the SOA 14. The SOA 14 is optically coupled to the waveguide 16 containing an array of reflective optical elements (gratings G) to be interrogated. The interrogation system further includes an optical detector 18, optically coupled to the SOA 14, operable to evaluate the wavelength of a returned optical pulse transmitted by the SOA 14.

A fiber-optic bundle based optical coherence tomography (OCT) probe method is demonstrated in a multimode optical fiber bundle based OCT system. The system can achieve a lateral resolution of 12 μm and an axial resolution of 10 μm using a super-luminescent diode source. This imaging approach eliminates any moving parts in the probe and has a primary advantage for use in extremely compact and safe OCT endoscopes to image internal organs and great potential to be combined with confocal endoscopic microscopy.

The present invention provides an apparatus and method for high resolution spectroscopy using a narrow light beam source such as a superluminescent diode (SLD) and a tunable optical filter (TOF) for analyzing a formation fluid sample downhole and at the surface to determine formation fluid parameters. The SLD and TOF have a matching etendue. The analysis comprises determination of gas oil ratio, API gravity and various other fluid parameters which can be estimated after developing correlations to a training set of samples using a neural network or a chemometric equation.

An optical interrogation system 10 includes optical amplifying and gating apparatus, in the form of a semiconductor optical amplifier (SOA) 14 and an optical source 12, 14. Drive apparatus 22 (an electrical pulse generator driven by a variable frequency oscillator) is provided to generate electrical drive pulses (see inset (a)) which are applied to the SOA 14, to cause the SOA 14 to switch on and off. The optical source comprises a super-luminescent diode (SLD) 12, the CW output from which is gated into optical pulses by the SOA 14. The SOA 14 is optically coupled to the waveguide 16 containing an array of reflective optical elements (gratings G) to be interrogated. The interrogation system further includes an optical detector 18, optically coupled to the SOA 14, operable to evaluate the wavelength of a returned optical pulse transmitted by the SOA 14.

Integrated spectroscopy systems are disclosed. In some examples, integrated tunable detectors, using one or multiple Fabry-Perot tunable filters, are provided. Other examples use integrated tunable sources. The tunable source combines one or multiple diodes, such as superluminescent light emitting diodes (SLED), and a Fabry Perot tunable filter or etalon. The advantages associated with the use of the tunable etalon are that it can be small, relatively low power consumption device. For example, newer microelectrical mechanical system (MEMS) implementations of these devices make them the size of a chip. This increases their robustness and also their performance. In some examples, an isolator, amplifier, and / or reference system is further provided integrated.

Systems and methods for providing a line-scanning laser ophthalmoscope (LSLO) are disclosed. The LSLO uses a substantially point source of light, such as an infrared laser or a super-luminescent diode. The point source is expanded to a line. The LSLO scans the line of light in a direction perpendicular to the line across a region of an eye having an undilated pupil The reflected light is received confocally, using monostatic beam geometry. A beam separator, such as a turning prism or mirror, diverts one of the incoming light and the reflected light to separate the light. An optical stop prevents non-confocally received light from reaching a one-dimensional detector, such as a linear CCD array. An electrical signal responsive to the output light at each of a plurality of locations along the line of output light is processed to provide images of the scanned portion of the eye.

Systems and methods for providing a line-scanning laser ophthalmoscope (LSLO) are disclosed. The LSLO uses a substantially point source of light, such as an infrared laser or a super-luminescent diode. The point source is expanded to a line. The LSLO scans the line of light in a direction perpendicular to the line across a region of an eye having an undilated pupil The reflected light is received confocally, using monostatic beam geometry. A beam separator, such as a turning prism or mirror, diverts one of the incoming light and the reflected light to separate the light. An optical stop prevents non-confocally received light from reaching a one-dimensional detector, such as a linear CCD array. An electrical signal responsive to the output light at each of a plurality of locations along the line of output light is processed to provide images of the scanned portion of the eye.

The invention relates to an unbalanced interferometer based fiber bragg grating (FBG) demodulation system and method, belonging to the technical field of fiber optic sensing. The system sequentially passes through a superluminescent diode (SLD) or an amplified spontaneous emission (ASE) broadband light source, an optic isolator, a circulator or a coupler, and a fiber bragg grating and returns back to the circulator or the coupler, and then passes through the coupler, an unbalanced Michelson interferometer with two channels and a Faraday rotator mirror and returns back to an interferometer and the coupler or passes through a Mach-Zehnder interferometer with two channels and the coupler, wherein one channel of the interferometer is wound around a piezoelectric ceramic or an electrooptical modulator, and an acousto-optic modulator, finally passes through a dense wave division multiplexer and a photoelectric detector and is connected with an ARCTAN based PGC (Phase Generation Carrier) signal response demodulation module. The invention has the advantages; by adopting the combination of the an FBG sensor and ARCTAN-based PGC phase modulation, the system has high sensitivity, large dynamic range and good linearity, good response to an abrupt signal and easiness of multiplexing, low cost and easiness of implementing.

The present invention provides an apparatus and method for high resolution spectroscopy using a narrow light beam source such as a superluminescent diode (SLD) and a tunable optical filter (TOF) for analyzing a formation fluid sample downhole and at the surface to determine formation fluid parameters. The SLD and TOF have a matching etendue. The analysis comprises determination of gas oil ratio, API gravity and various other fluid parameters which can be estimated after developing correlations to a training set of samples using a neural network or a chemometric equation.

Provided are a reflective semiconductor optical amplifier (R-SOA) and a superluminescent diode (SLD). The R-SOA includes: a substrate; an optical waveguide including a lower clad layer, an active layer independent of the polarization of light, and an upper clad layer sequentially stacked on the substrate, the optical waveguide comprising linear, curved, and tapered waveguide areas; and a current blocking layer formed around the optical waveguide to block a flow of current out of the active layer, wherein the linear and curved waveguide areas have a single buried hetero (BH) structure, and the tapered waveguide area has a dual BH structure.

The invention belongs to the field of blood vessel endoscopic imaging and discloses a device and method for endovascular optical coherence tomography - opto-acoustic - ultrasonic multimode imaging. The device comprises a computer, an optical coherence tomography (OCT) excitation and collection system, an opto-acoustic signal excitation and collection system, an ultrasonic signal excitation and collection system and an integrated probe. The OCT excitation and collection system comprises a field programmable logic array (PFGA) panel, a superluminescent diode, an isolator, a first optical fiber coupler, a reference arm, a linear array charge coupled device (CCD) and a first collecting card. The opto-acoustic signal excitation and collection system comprises a pulsed laser, a diaphragm, a second optical fiber coupler and a doubly clad optical fiber. The ultrasonic signal excitation and collection system comprises a pulse ultrasonic emitter / receiver, a signal amplifier, a signal filter and a second collecting card. The OCT, opto-acoustic and ultrasonic tri-modal blood vessel endoscopic imaging system integrates three imaging modes and respective advantages thereof, and multi-parameter physiological function information and multiscale structural information of a blood vessel can be obtained.

A superluminescent diode according the present invention employs a uniform AlGaInAs quantum well on an InP substrate, emitting in a range of 1100 to 1800 nm. The favorable conduction band: valence band offset ratio of this material system enables superluminescent diodes which simultaneously provide high power and large optical bandwidth. A recent reduction to practice of the present invention simultaneously demonstrates output power exceeding 100 mW and bandwidth exceeding 100 nm. A preferred embodiment of this invention uses multiple uniform AlGaInAs quantum wells with two confined quantum states and energetic separation in a range of 100-130 nm. An alternate preferred embodiment uses non-uniform wells, with each well having two confined quantum states. The present invention is particularly useful in time domain and spectral domain optical coherence tomography systems, providing increased resolution and tissue penetration for in-vivo imaging.

Provided is a super luminescent diode having low power consumption due to low threshold current and a high output power in low-current operation, which is suitable for an external cavity laser. The super luminescent diode for use in the external cavity laser is divided into a super luminescent diode (SLD) region and a semiconductor optical amplifier (SOA) region to provide a light source having a low threshold current and a nearly double output power of a conventional SLD.A super luminescent diode-integrated reflective optical amplifier includes a substrate that has a super luminescent diode (SLD) region and a semiconductor optical amplifier (SOA) region for amplifying light generated from the SLD region, an optical waveguide that has a buried heterostructure, the buried heterostructure including an active layer extending over the SLD and SOA regions on the substrate and tapered in the SOA region; a current blocking layer formed around the active layer for blocking a current flow to layers other than the active layer, the current blocking layer including a stack of semiconductor layers having different conductivity types; and a clad layer formed on the optical waveguide and the current blocking layer.

An optical broadband emitter and the method of making such a broadband emitter are described. Intermixing of closely coupled multiple quantum wells, especially carrier tunneled coupled quantum wells, is described using nano-imprinting of a gel like dielectric layer such as a sol-gel derived SiO2 layer into multiple stepped or graded sections to form intermixing cap regions of different thickness. A thermal annealing process is performed to condense the SiO2 intermixing cap and induce intermixing. A superluminescent diode is described having multiple electrodes deposited over multiple sections of different bandgaps in which each individual electrode can be either forward or reverse biased to different degrees such that each diode section can individually function as a sub-band spontaneous emitter, an amplifier / attenuator, a photon-absorber, a transparent waveguide, or a photodetector / optical power monitor.

A 1.55 μm SLD having a laser diode (LD) region and a semiconductor optical amplifier (SOA) region, and a method of fabricating the same, are disclosed. The SLD includes: an InP substrate having a LD region and a SOA region for amplifying light emitted from the LD region; an optical waveguide having a BRS (buried ridge strip) structure having an active layer of resonant strip pattern formed on the InP substrate and extending from the SOA region to the LD region; a first electrode formed on the active layer in the SOA region, a second electrode formed on the active layer in the LD region and electrically isolated from the first electrode; and a current blocking region interposed between the first electrode and the second electrode in order to electrically isolate the first electrode and the second electrode from each other.

An optical broadband emitter and the method of making such a broadband emitter are described. Intermixing of closely coupled multiple quantum wells, especially carrier tunneled coupled quantum wells, is described using nano-imprinting of a gel like dielectric layer such as a sol-gel derived SiO2 layer into multiple stepped or graded sections to form intermixing cap regions of different thickness. A thermal annealing process is performed to condense the SiO2 intermixing cap and induce intermixing. A superluminescent diode is described having multiple electrodes deposited over multiple sections of different bandgaps in which each individual electrode can be either forward or reverse biased to different degrees such that each diode section can individually function as a sub-band spontaneous emitter, an amplifier / attenuator, a photon-absorber, a transparent waveguide, or a photodetector / optical power monitor.

A superluminescent diode and a method for implementing the same, wherein the method includes growing a first epi layer on top of an SI (semi-insulating substrate); re-growing a butt based on the first epi layer; forming a tapered SSC (spot size converter) on the re-grown butt layer; forming an optical waveguide on an active area that is based on the first epi layer and on an SSC area that is based on the tapered SSC; forming an RWG on the optical waveguide; and forming a p-type electrode and an n-type electrode.

The invention relates to a fabrication method of a superluminescent diode chip. The method comprises the following steps of one-step epitaxy, ridge forming, secondary epitaxy, isolation region forming, P-type electrode evaporation, N-type electrode evaporation, alloy and film coating. The invention also relates to a superluminescent diode chip fabricated according to the fabrication method. The chip fabricated according to the invention has the characteristics of low polarization, high output power and low spectrum corrugation.

Provided are a superluminescent diode with a high optical power and a broad wavelength band, and a method of fabricating the same. The superluminescent diode includes: at least one high optical confinement factor (HOCF) region; and at least one low optical confinement factor (LOCF) region having a lower optical confinement factor than the HOCF region. The method includes obtaining a difference of optical confinement factors in the HOCF region and the LOCF region through a selective area growth method, the selective area growth method using a deposition thicknesses difference of thin layers according to a width difference of openings that expose a substrate.

A light emitting device includes a first layer that generates light by an injection current, the first layer is provided with a first optical waveguide extending from a first light emitting section disposed on a first side surface to a first light reflecting section disposed on a second side surface, a second optical waveguide extending from the first light reflecting section to a second light reflecting section disposed on a third side surface, and a third optical waveguide extending from the second light reflecting section to a second light emitting section disposed on the first side surface, an element of the group II or the group XII is diffused in the first light reflecting section and the second light reflecting section, and a first light emitted from the first light emitting section and a second light emitted from the second light emitting section are emitted in the same direction.

The present invention provides a multi-quantum-well superluminescent diode. It is characterized by that it adopts AlGaInAs / InP materials, the luminescent wavelength range of its active region is 1.25 micrometers to 1.65 micrometers, and on the n-type InP substrate successively are set lower clad, upper and lower respective limiting layers and multi-quantum-well active region positioned in them, in which the thickness of the well is 5-10 nm, and the total thickness of active region well barrier is 10-500 nm. On the upper limiting layer are successively set upper clad, etching cut-off layer, optical limiting layer and ohmic contact layer. It adopts an inverted mesa ridge waveguide structure, its two sides are equipped with polymer plane buried layer respectively, and its upper surface is equipped with plane electrode, in which the included angle theta of waveguide direction and light-outgoing end face of SLED is 75-85 deg.

Provided is a super luminescent diode having low power consumption due to low threshold current and a high output power in low-current operation, which is suitable for an external cavity laser. The super luminescent diode for use in the external cavity laser is divided into a super luminescent diode (SLD) region and a semiconductor optical amplifier (SOA) region to provide a light source having a low threshold current and a nearly double output power of a conventional SLD.A super luminescent diode-integrated reflective optical amplifier includes a substrate that has a super luminescent diode (SLD) region and a semiconductor optical amplifier (SOA) region for amplifying light generated from the SLD region, an optical waveguide that has a buried heterostructure, the buried heterostructure including an active layer extending over the SLD and SOA regions on the substrate and tapered in the SOA region; a current blocking layer formed around the active layer for blocking a current flow to layers other than the active layer, the current blocking layer including a stack of semiconductor layers having different conductivity types; and a clad layer formed on the optical waveguide and the current blocking layer.

An apparatus for producing wavelength stabilized electromagnetic radiation is provided, the apparatus comprising a broadband semiconductor radiation source configured to produce broadband electromagnetic radiation having a mean wavelength λm, and a bandpass radiation filter, an input of said bandpass radiation filter being in optical connection to an output of said radiation source, and a common temperature stabilizer being in thermal contact with both, the radiation source and the radiation filter. In a preferred embodiment, the radiation source—which is, for example, a superluminescent light emitting diode—and the bandpass radiation filter are provided on a common mount which is in contact with a thermoelectric cooler acting, together with temperature sensing means and control means, as temperature stabilizer.

The present invention provides a superluminescent diode, which has a wide wavelength bandwidth and a high optical power, and a method of manufacturing the same. The superluminescent diode includes an active layer having a chirped quantum dot (CQD) structure formed over the substrate, wherein the active layer emits lights of at least two different wavelengths.

A projector includes: at least one light emitting device having a light emitting element adapted to emit a first outgoing light and a second outgoing light proceeding in a direction different from a direction of the first outgoing light; a first light modulation device adapted to modulate the first outgoing light in accordance with image information; a second light modulation device adapted to modulate the second outgoing light in accordance with image information; and a projection device adapted to project the light modulated by the first light modulation device and the light modulated by the second light modulation device, wherein the light emitting element is a super luminescent diode provided with a stacked structure having an active layer sandwiched between a first cladding layer and a second cladding layer, and the active layer has a first emission surface adapted to emit the first outgoing light and a second emission surface adapted to emit the second outgoing light.

Provided are a reflective semiconductor optical amplifier (R-SOA) and a superluminescent diode (SLD). The R-SOA includes: a substrate; an optical waveguide including a lower clad layer, an active layer independent of the polarization of light, and an upper clad layer sequentially stacked on the substrate, the optical waveguide comprising linear, curved, and tapered waveguide areas; and a current blocking layer formed around the optical waveguide to block a flow of current out of the active layer, wherein the linear and curved waveguide areas have a single buried hetero (BH) structure, and the tapered waveguide area has a dual BH structure.

A light emitting device includes a laminated body having an active layer, a first cladding layer, and a second cladding layer, the active layer constitutes an optical waveguide, the optical waveguide includes a first portion connecting a first exit section and a first reflecting section to each other, a second portion connecting the first reflecting section and a second reflecting section to each other, and a third portion connecting the second reflecting section and a second exit section to each other, and a current density in the first portion and a current density in the third portion are higher than a current density in the second portion.

A superluminescent diode according the present invention employs a unoform AlGaInAs quantum well on an InP substrate, emitting in a range of 1100 to 1800 nm. The favorable conduction band: valence band offset ratio of this material system enables superluminescent diodes which simultaneously provide high power and large optical bandwidth. A recent reduction to practice of the present invention simultaneously demonstrates output power exceeding 100 mW and bandwidth exceeding 100 nm. A preferred embodiment of this invention uses multiple uniform AlGaInAs quantum wells with two confined quantum states and energetic separation in a range of 100-130 nm. An alternate preferred embodiment uses non-uniform wells, with each well having two confined quantum states. The present invention is particularly useful in time domain and spectral domain optical coherence tomography systems, providing increased resolution and tissue penetration for in-vivo imaging.