1238 results about "Laser diode" patented technology

A cleaner head for a vacuum cleaner includes a laser diode for illuminating debris located upon a region of a work surface located in front of the cleaner head with green light.

The invention provides a solution concentration real-time detection method based on focusing offset of a compound lens, which comprises the following steps: step A, laser emitted by a laser diode is collimated into parallel light through a plano-convex lens, the parallel light is emitted into a sample cell through a glass window, and then the parallel light is emitted by the compound lens to be imaged on an image sensor; step B, the parallel light is emitted to an image sensor through a compound lens to be imaged into two light spots, the distance # imgabs0 # between the two light spots on the image sensor is recorded, and the solution concentration is inversed through the distance # imgabs1 # between the two light spots; step C, respectively detecting the temperature and the pressure intensity of the solution to be detected through a temperature sensor and a pressure sensor, and compensating the influence of the temperature and the pressure intensity on measurement through an algorithm; on the basis of light spot form analysis of the compound lens, the solution concentration is inversed, the resolution capability of a low-concentration transparent solution is improved, and the detection stability of transparent solutions such as alcohol is improved.

Various illustrative aspects are directed to a data storage device comprising a disk, a read / write head configured to read data from and write data to the disk, a laser diode (LD) coupled to a nearfield transducer configured to heat an area of the disk near the read / write head, a first resistive temperature detector (RTD), a second RTD, and one or more processing devices configured to: apply a laser bias to the LD during a write operation; obtain a plurality of differential signal measurements, based at least in part on a plurality of measurements from each of the first and second RTDs; and adjust the laser bias applied to the LD, based at least in part on comparing the plurality of differential signal measurements to a target value for the differential signal.

The invention discloses a polarization-state-based optical fiber vibration sensing system and application, and relates to the technical field of optical fiber sensing, and the polarization-state-based optical fiber vibration sensing system mainly comprises a transmitting end and a receiving end. The transmitting end comprises a laser diode, a first erbium-doped optical fiber amplifier, a first circulator, a polarization scrambler, a single-mode optical fiber link, a second circulator and a second erbium-doped optical fiber amplifier which are connected in sequence; and the receiving end comprises a polarization beam splitter, a first shunt module, a second shunt module, an optical mixer, a first balanced photoelectric detector, a second balanced photoelectric detector, a third balanced photoelectric detector and a polarization analysis module. According to the optical fiber vibration sensing system based on the polarization state and the application, the vibration monitoring performance and reliability in a long-distance and high-noise environment can be improved.

The utility model provides a multi-single-tube semiconductor laser diode densely-arranged beam shaping and coupling device, comprising a semiconductor array laser used for emitting a first beam array and carrying out fast and slow axis collimation to obtain a second beam array; the light beam reflection separation system is used for performing separation arrangement on the second light beam array; the fast and slow axis conversion system is arranged on a light path where the light beam is emitted by the light beam reflection separation system and used for rotating the fast and slow axis of the second light beam array which is separated and arranged by 90 degrees; the confocal beam shrinking and expanding system is used for simultaneously focusing the fast axis light spots and the slow axis light spots of the separated and arranged second light beam array and then carrying out fast axis beam shrinking and slow axis beam expanding to obtain a third light beam array; the light beam reflecting and combining system is arranged on the light beam emergent light path of the confocal beam shrinking and expanding system and is used for closely arranging the third light beam array; and the focusing system is arranged on a light path where the light beams are emitted by the light beam reflecting and combining system, and is used for focusing the light spots of the closely arranged third light beam array to a target size.

To improve the luminous efficiency of a UV light-emitting device, the UV light-emitting devices disclosed herein have an AlGaN-based crystal or an InAlGaN-based crystal, and comprise an emission layer, at least one electron blocking layer, a first p-type doped layer, and a composition gradient layer in which the Al composition ratio varies depending on the position over a thickness direction of the layer stack, stacked in this order in the direction of the flow of electrons. The Al composition ratio varies depending on the position over the thickness direction in the composition gradient layer. The UV light-emitting devices are implemented as UV-region light-emitting diodes and laser diodes.

The invention provides a mode-hopping-free large-range continuous tunable external cavity semiconductor laser, which comprises a laser diode (1), a collimating lens (2), a polarization splitting prism (3), a narrow-band interference sheet (4), a prism-type super-strong-level reflective film (5) and a piezoelectric module (6), the laser diode (1), the collimating lens (2) and the polarization splitting prism (3) are sequentially arranged on a light path, and the narrow-band interference sheet (4), the prism-type super-strong-level reflective film (5) and the piezoelectric module (6) are bonded together. The rotation axis is located on the light path of the laser and coincides with the rear surface of the piezoelectric module (6). According to the mode-hopping-free large-range continuous tunable external cavity semiconductor laser, the sensitivity of the laser frequency to the rotation angle of the narrow-band interference sheet is utilized, and the angle and the cavity length of the interference sheet are changed at the same time, so that the transmission peak center frequency of the interference sheet and the specific cavity mode frequency are highly synchronized along with the change of the angle; according to the laser, mode hopping of the laser output frequency is avoided, and continuous tunability of the output frequency along with the rotation angle of the cavity mirror is guaranteed.

The invention provides a micro-integrated temperature control heating semiconductor laser diode and a manufacturing method thereof, which are used for solving the technical problems of lower temperature control precision, more combined devices, higher difficulty of a packaging process and higher cost in the conventional packaged laser diode. The invention provides a micro-integrated temperature-control heating semiconductor laser diode which can accurately control the temperature, is low in cost and can simplify the packaging process, the micro-integrated temperature-control heating semiconductor laser diode comprises a laser chip, the laser chip sequentially comprises a substrate, a first buffer layer, an active layer, a second buffer layer and a passivation layer from bottom to top, and the back surface of the substrate is provided with a negative electrode; two grooves are etched on the passivation layer, and a ridge strip between the two grooves forms a waveguide; and a heating resistor and a thermistor are respectively arranged on two sides of the two grooves. A heating function and a temperature measuring function are integrated on the semiconductor laser by adopting a micro-integration technology, so that the number of used devices is effectively reduced, the packaging volume is reduced, the packaging procedure is simplified, and the packaging cost of the devices is reduced.

The invention discloses an optical test system and method for measuring the total temperature of a supersonic combustion flow field, and relates to the field of combustion flow field measurement. The system comprises supersonic combustion incoming flow, a time sequence synchronizer, a first laser, a first focusing lens, a first total reflection plane mirror, a second laser, a second focusing lens, a sheet light lens, a second total reflection plane mirror, a computer, an ICCD, a tunable laser diode, a laser controller, a photoelectric detector, an industrial personal computer and a signal monitor. On the basis of a non-contact optical testing technology, the local total temperature is obtained by measuring the speed and the static temperature of the combustion flow field at the same time on the premise that the flow structure and the combustion state of the combustion flow field are not damaged, the structure of the supersonic combustion flow field is not obviously affected, unnecessary oblique shock waves are not caused, and the measurement accuracy is high. And the local and downstream flow and combustion states of the tested combustion flow field are not influenced.

A system is described for determining accuracy of an eye-tracking device using an oculomotor simulator assembly. The system receives instructions specifying movement for simulated eyeballs in the oculomotor simulator assembly. The system enables movement of the simulated eyeballs based on the received instructions. The system obtains ground-truth values for three-dimensional gaze directions of the simulated eyeballs in response to the enabled movement using projections of laser diodes from the center of the simulated eyeballs during the specified movement. The system additionally gathers three-dimensional gaze directions as determined by the eye-tracking device that is tracking the simulated eyeballs during the specified movement. The system determines accuracy of the eye-tracking device based on the obtained ground-truth values and the determined three-dimensional gaze directions from the eye-tracking device.

Various illustrative aspects are directed to a data storage device, method, and one or more processing devices that are configured to: maintain respective measures of write commands associated with respective ones of shingled magnetic recording (SMR) zones defined in a data storage device, wherein data associated with the write commands is stored in a write cache associated with the data storage device; select one of the SMR zones based on the respective measures; perform a pre-heat operation of a laser diode included in a head associated with the selected one of the SMR zones; and perform a continuous write operation in the selected one of the SMR zones following the pre-heat operation, wherein the continuous write operation writes at least a portion of data stored in the write cache associated with the selected one of the SMR zones.

The invention relates to the technical field of photoelectric detection, in particular to a laser diode state monitoring method and system based on multi-parameter fusion, and the method comprises the steps: carrying out the laying and collection of a plurality of parameters based on the working condition of a laser diode, including current, temperature and optical feedback signals, and carrying out the dynamic fusion to construct a damage index; establishing a grading early warning mechanism, correspondingly setting a judgment threshold value, and triggering early warning in combination with the damage index; the temperature is detected periodically, parameter drift influenced by the temperature is corrected based on a damage index, and state monitoring of the laser diode is achieved; by dynamically fusing a plurality of parameters of current, temperature and optical feedback signals, a multi-dimensional damage index is established, so that the influence of a plurality of indexes on laser diode damage is synthesized, and the recognition rate of early damage is improved; and establishing a grading early warning mechanism from a slight state to a serious state, making a corresponding early warning response, and advancing fault recognition of the laser diode to a reversible stage.

Provided is a medical skin treatment device including a control unit for controlling the operation of the skin treatment device; a main body which includes a transfer unit and a power supply unit; and a handpiece which is supplied with power from the power supply unit and controlled by the control unit and one side of which is brought into contact with a patient's skin to irradiate same with laser beams. The handpiece includes at least four different laser diodes; the at least four laser diodes radiate laser beams of four different wavelengths and comprise first laser diodes, second laser diodes, third laser diodes, and fourth laser diodes; the number of the first laser diodes is 30 percentage or less of the total number of the laser diodes; and the number of the fourth laser diodes is 25 percentage or greater of the total number of the laser diodes.

A self-calibrating driver circuit (100, 300, 400, 500, 700) for a laser diode is disclosed. The circuit comprises a configurable current source (105, 305, 405, 505), a current mirror (115, 315, 415) configured to mirror a current from the configurable current source to a first transistor (120, 320, 420, 520, 720) and to a second transistor (125, 325, 425, 725), and a control circuit (140, 340, 440). The control circuit is configured to monitor a current through the first transistor at a first time, and to configure the current source based on the current through the first transistor to provide a desired current to the second transistor for driving the laser diode at a subsequent second time. A radiation-emitting device comprising one or more of the self-calibrating driver circuits and at least one radiation-emitting element is also disclosed.

The invention discloses a high-resolution local brain blood oxygen change measuring method based on self-detection-mutual detection combination, which comprises the following steps: placing two optical fiber probes of an optical fiber brain blood oxygen detection system on the brain scalp, and dividing two self-detection channels and one mutual detection channel according to different light diffusion paths; calculating a time-dependent average partial path length; a laser diode is driven to emit near-infrared pulse light, and two groups of time-resolved reflectivity signals of the three channels are obtained; performing curve optimization on the time-resolved reflectivity signals of the channels 1, 2 and 3 measured twice, and solving an absorption change equation set; solving absorption change values of the linear equations of the channels 1, 2 and 3; obtaining a relational expression between the change of the absorption coefficient of the local areas with different wavelengths and the blood oxygen concentration; and solving the relational expression group of the same wavelength and the local region to obtain the blood oxygen concentration change of the local region. The method has the advantage of improving the spatial resolution of the time domain fNIRS and the signal-to-noise ratio of the time gate signal of the time resolution reflectivity.

A laser apparatus includes: one or more laser diodes and two or more optical combiners. Further, output sides of the one or more laser diodes are connected to an input side of one optical combiner among the two or more optical combiners, and an output side of the one optical combiner is connected to an input side of an optical combiner other than the one optical combiner.

A beam laser diode takes a silicon-based nitride epitaxial wafer as a carrier and comprises a silicon substrate layer, an aluminum nitride layer, a u-type gallium nitride layer, an n-type gallium nitride layer, a quantum well layer, a p-type gallium nitride layer and a SiO2 layer which are sequentially arranged from bottom to top, the p-type electrode is arranged on the p-type gallium nitride layer, and the n-type electrode is arranged on the edge of the n-type gallium nitride layer. A nitride material on a silicon substrate is used for preparing a micro-beam stress sensitive area LD by utilizing photoetching and ICP (Inductively Coupled Plasma) etching processes for emitting light, and after electrification, the laser LD is obtained in the stress sensitive area of the beam. Under the power-on condition, before and after acceleration loading, due to the fact that quantum limits the stark effect, the frequency wavelength of laser changes, and the magnitude of the acceleration can be sensed through difference frequency.

The invention relates to a method for producing a plurality of surface-emitting semiconductor laser diodes, including the following steps:—providing a growth substrate,—applying a mask layer with a plurality of openings onto the growth substrate, so that regions of the growth substrate are exposed through the openings,—applying a first intermediate layer at least onto the exposed regions of the growth substrate, the first intermediate layer having a quasi two-dimensional material, and—epitaxial growing of an epitaxial semiconductor layer sequence on the first intermediate layer, wherein the epitaxial semiconductor layer sequence has an active layer for generating electromagnetic radiation.

The invention relates to a miniaturized medium-long wave infrared solid-state laser in which a thulium-doped laser directly pumps a ZGP crystal, the thulium-doped laser takes two laser diodes with the central emission wavelength of 793 nm as pumping sources, two Tm: YAP crystals with the same parameters are cascaded and placed in a U-shaped resonant cavity to serve as laser gain media, and an acousto-optic Q crystal controls intra-cavity loss in the resonant cavity, so that the thulium-doped laser directly pumps the ZGP crystal. Pulse laser with the wavelength of 1.94 m is output; the 1.94 m pulse thulium laser serves as pump light and passes through the ZGP-OPO module, and 2.8 m signal light and 6.2 m idler frequency light are obtained. The Tm laser outputs 1.94 m laser through primary oscillation to directly serve as a pump source, the ZGP-OPO outputs medium-long wave infrared laser in a nonlinear mode, the overall light path structure of the medium-long wave laser is simplified, and the electro-optical conversion efficiency is improved.

A vertical cavity surface emitting laser diode (VCSEL) includes a substrate, a lower Bragg reflector (DBR) layer, an active region, an upper Bragg reflector (DBR) layer, and a current confinement layer. The lower DBR layer is on the substrate. The active region is on the lower DBR layer on the active region. The current confinement layer is inside or outside the active region. When the current confinement layer comprises a compound containing phosphorus, such as AlAsP or AlGaAsP, and the phosphorus (P) content is within a specific range, the insulation rate of the current confinement layer will not be excessively fast to the point of being difficult to control. Additionally, the reproducibility of the aperture in the current confinement layer between batches of the VCSEL production is improved. Furthermore, the divergence angle of the VCSEL can be further reduced, thereby significantly enhancing the sensing capabilities of Lidar or 3D sensing.

The utility model discloses a high-order transverse mode controllable space-time mode locking all-fiber laser, which relates to the field of fiber lasers and comprises an annular laser system and a feedback system. The ring laser system comprises a laser diode pumping source, a wavelength division multiplexer, a gain fiber, a high-order transverse mode generation module, a multi-mode output coupler, a saturable absorber, a polarization controller, an isolator and an out-of-cavity coupler. The feedback control system comprises an image acquisition module, an image processing module and a feedback control circuit. Space-time mode locking is achieved based on the all-fiber saturable absorber, and the device has the advantages of being simple in structure, small in environmental influence, good in stability and the like. By inserting the multi-core multimode optical fiber and the conical multimode optical fiber into the all-fiber mode-locked laser, excitation of a high-order transverse mode and screening of the high-order transverse mode are effectively achieved. By externally connecting a feedback control system, the high-order transverse mode output by the laser is selected, and the space-time mode-locked all-fiber laser with controllable output high-order transverse mode is effectively realized.

The invention relates to a photomultiplier testing device and a photomultiplier testing method, in particular to a pulse saturation recovery characteristic testing device and a pulse saturation recovery characteristic testing method for a micro-channel plate type photomultiplier, and solves the problem that an existing MCP-PMT pulse saturation recovery characteristic testing device does not meet actual application requirements. And the pulse saturation recovery characteristics under different saturation depths and different recovery degrees cannot be evaluated. According to the invention, a pulse saturation recovery characteristic test is carried out on the MCP-PMT by using a laser diode and an optical attenuation sheet in a camera obscura environment, a pulse signal generator, a power divider, a combiner, a high-voltage source, a digitizer and a data processing unit, and the pulse signal generator successively generates two paths of driving pulse signals with different pulse widths. The method accords with the actual application requirement of the MCP-PMT working in a linear state, the measurement result can reflect the saturation recovery characteristic of the MCP-PMT in the actual application, and the pulse saturation recovery characteristic of the MCP-PMT under different saturation depths and different recovery degrees can be evaluated.

The invention relates to a 213nm all-solid-state deep ultraviolet laser and application thereof, and belongs to the technical field of lasers. The laser comprises a laser diode, a pump light focusing system, a pump end mirror, a laser crystal, a deep ultraviolet output mirror, a sum frequency crystal, a frequency doubling crystal and a total reflection end mirror which are sequentially arranged along a light path, the pump end mirror, the deep ultraviolet output mirror and the total reflection end mirror form a V-shaped resonant cavity, and the laser crystal, the sum frequency crystal and the frequency doubling crystal are all cuboids. And birefringence main shafts of the laser crystal, the sum frequency crystal and the frequency doubling crystal are arranged in a staggered manner. Visible red light with the wavelength of 640 nm is adopted as fundamental frequency laser, only two-step frequency conversion is needed for output from the fundamental frequency laser to 213 nm, and the laser has the advantages of being simplified in process, small in size, easy to adjust, high in conversion efficiency, large in output power, low in manufacturing cost, stable in performance and the like.

To provide a laser diode chip capable of emitting RGB light with one chip and also capable of obtaining high emission efficiency even when a chip is miniaturized.SOLUTION: A laser diode chip has, on an n-type AlxGa1-xN layer (0≤x≤1), AlGaInN laser diode structures (B', G', R') emitting blue light, green light and red light, respectively. These laser diode structures have: an insulating film (703) having at least one rectangular opening (703a) on the n-type AlxGa1-xN layer; a polygonal truncated pyramid-shaped n-type AlyGa1-yN layer (0≤y≤1) (704) on the n-type AlxGa1-xN layer in a portion of the opening; active layers (705-707) each provided along a top surface and a side surface of the n-type AlyGa1-yN layer; p-type AlzGa1-zN layers (0≤z≤1) (708-710) covering each active layer; a p-side electrode (711) on the p-type AlzGa1-zN layers; and an n-side electrode (712) provided on the n-type AlxGa1-xN layer or a rear face thereof.SELECTED DRAWING: Figure 37B

The present disclosure provides systems and methods for coupling light in imaging systems. One such system comprises a metalens doublet structure having a first substrate; a first metalens structure provided at a surface of the first substrate and comprising a plurality of first scatterers; and a second metalens structure provided at a second substrate or on another surface of the first substrate and comprising a plurality of second scatterers. Accordingly, the plurality of first scatterers is configured to reshape the intensity distribution of light that is received by the first metalens structure at a location of the second metalens structure; and the plurality of second scatterers is configured to change a wavefront of the light outputted from the first metalens structure and incident on the second metalens structure.

The invention discloses an underwater measurement method based on a zoom camera and a laser diode, which adopts the zoom camera to measure a laser spot image and greatly expands the application scene of equipment. The lasers A, B and C are manufactured based on laser diodes, the linearity of power adjustment can be well guaranteed, and measurement errors caused by too bright or too dark laser spots in images shot by the camera can be effectively avoided. According to the underwater measurement method provided by the invention, not only can the distance of the target object be measured, but also the feature size of the target object can be measured; in the installation process of the underwater measurement device, an error measurement link of the installation position of the laser is added, and the error is fully considered when the feature size of the target object is measured, so that the measurement precision is improved. During calibration, the average value of the height of the triangle and the corresponding bottom edge ratio in the maximum magnification and minimum magnification states of the zoom camera is taken as an independent variable, so that the influence of magnification change on calibration precision is reduced.

The invention relates to the technical field of laser diodes, and provides a laser diode array side unidirectional pumping cavity comprising a pumping source used for emitting pumping light; the diffuse reflection cavity is arranged on one side of the pumping source, the inner side wall of the diffuse reflection cavity comprises a curved surface part and a straight inclined surface part, a gap is formed in the center line of the straight inclined surface part, and the gap serves as an incident port of the pumping light; the incident port is opposite to the light-emitting surface of the pumping source; the cooling pipe is arranged on the side, away from the pumping source, of the diffuse reflection cavity; the laser gain medium and the cooling pipe are coaxially arranged, the laser gain medium is located on the inner side of the cooling pipe, and the space between the laser gain medium and the cooling pipe is filled with cooling liquid. Through the arrangement of the curved surface part and the straight inclined surface part of the diffuse reflection cavity and the arrangement of the cooling pipe and the laser gain medium on the side, far away from the pumping source, of the diffuse reflection cavity, uniformization can be carried out on one-way pumping light entering the laser gain medium, and one-way high-power and high-uniformity pumping of the laser gain medium is achieved.

The invention provides a solution concentration real-time detection method based on cylindrical lens focusing offset, which comprises the following steps: step A, laser emitted by a laser diode is collimated into parallel light through a plano-convex lens, the parallel light is emitted into a sample cell through a glass window, and the sample cell is used for detecting the concentration of a sample; and then the light is emitted by the cylindrical lens and is imaged on the image sensor. B, the parallel light is imaged into a light spot on the image sensor after being emitted by the cylindrical lens, the image sensor is driven by the stepping motor to move, the minimum light spot is found, the moving distance of the image sensor is recorded, and the solution concentration change is inversed through the moving distance; by introducing a cylindrical lens light path amplification mechanism, the detection precision is remarkably improved, the temperature drift is effectively inhibited, and the defect of insufficient sensitivity in the prior art is overcome.

The invention relates to a semiconductor base coating process, which specifically comprises the following steps: step one: using external cleaning equipment and detection equipment to comprehensively clean impurities from the semiconductor base and detect whether it is qualified; step two: sequentially inverting a number of semiconductor bases that have passed the detection on the coating equipment to perform coating operations; step three: taking the coated semiconductor off the coating equipment; after coating the organic high-temperature glue, a rotating cylinder drives a flip plate to rotate 180 degrees, at which time one end of the flip plate contacts a support seat, and at the same time, iron filings in a material storage tank will be attracted by the magnetism on a heat dissipation base, so that the iron filings are embedded in the organic high-temperature glue and adsorbed on the surface of the heat dissipation base at the same time, one end of the iron filings extends out of the organic high-temperature glue, and the other end thereof contacts the heat dissipation base, thereby increasing the heat dissipation area of ​​the heat dissipation base, and further improving the heat dissipation efficiency of the heat dissipation base for the laser diode.