24 results about "Optical limiting" patented technology

Vertical-cavity surface-emitting lasers (VCSELs) and associated methods of manufacturing are provided. An example VCSEL includes a first reflector, a second reflector, and an active region disposed between the first reflector and the second reflector. The VCSEL further includes an electrical aperture defining a current confinement region configured to direct current to the active region and an optical aperture defining a medium through which light produced by the active region is emitted from the VCSEL. At least one dimension of the optical aperture of the VCSEL is formed independent of the electrical aperture of the VCSEL. In some instances, the dimension of the optical aperture is a first diameter such that the first diameter of the optical aperture is formed independent of a second diameter defined by the electrical aperture.

The invention discloses a covalent organic framework material and a preparation method thereof, an optical limiting material and a preparation method and application thereof, and the preparation method comprises the following steps: carrying out solvothermal reaction on metal perfluorophthalocyanine and an amido-containing monomer in the presence of a first solvent and a catalyst to obtain the covalent organic framework material connected by piperazine bonds. The covalent organic framework material shows good nonlinear optical performance, and the covalent organic framework (COF) and polymethyl methacrylate (PMMA) optical limiting material is uniformly mixed, can be used for preparing optical plastics, and has extremely high application potential in practical application in the nonlinear optical field.

This invention discloses a method for preparing magnesium antimonide quantum dot optical limiting materials and their applications, belonging to the field of novel inorganic semiconductor quantum dot material preparation. The preparation method involves grinding magnesium antimonide powder in an agate mortar, then placing the ground magnesium antimonide powder in an appropriate amount of ionic liquid solvent. The solution is subjected to ice bath ultrasonic exfoliation, followed by a first centrifugation. The supernatant is then dialyzed, followed by a second centrifugation and freeze-drying to obtain magnesium antimonide quantum dot samples. The ionic liquid solvent used in this invention has advantages such as being green, environmentally friendly, having a high boiling point, and high conductivity. The obtained magnesium antimonide quantum dots have a size of 2 nm to 4 nm, exhibiting antisaturated absorption characteristics and high linear transmittance, balancing protective performance with normal optical functions, and showing good application prospects in fields such as nonlinear optics.

The invention relates to a copper nanocluster / fullerol nano composite material, a polymer nonlinear optical thin film and a preparation method and application of the polymer nonlinear optical thin film, and the copper nanocluster / fullerol nano composite material is a nano composite material which is formed by inducing self-assembly of Cu6 and hydroxyl fullerene C60-OH in an aqueous solution through hydrogen bond interaction and has a nano structure. The nonlinear absorption coefficient of the film obtained by adopting the copper nanocluster / fullerol nanocomposite material is as high as 35.5 * 10 < 4 > cm / GW when the laser energy is 1 mu J, and the optical limiting threshold value is as low as 0.008 J / cm < 2 >, so that the film is obviously superior to the existing metal cluster-based material. The method is simple and convenient in process and environment-friendly, and the prepared film has important application value in the fields of laser protection and precision optical equipment safety.

To provide a laser device having a higher modulation speed, a high device yield, and improved array compatibility under either cooled or uncooled operating conditions.SOLUTION: An active layer structure 20 between a semiconductor substrate 30 and a grating structure 40 configured for operation, comprising a common active layer, a first facet 50-1 and a second facet 50-2, wherein the grating structure comprises spatially adjacent integrated grating sections, a cladding structure 70 for optical confinement of laser light, a DFB structure 60-1 with a first grating section 42-1, and a DBR structure 60-2 with a second grating section 42-2, the first grating section and the second grating section share a common active layer for the integrated grating section, the DFB structure includes a first optical function as a lasing function, and the DBR structure includes a second DBR structure as an optical feedback.SELECTED DRAWING: Figure 1

This invention relates to a system and method for measuring the internal flow field of film cooling holes in aero-engine blades based on refractive index matching. The system includes a main flow section, a transparent material body below the main flow section, and film cooling holes embedded within the transparent material body. Cooling fluid flows through the film cooling holes. A laser is positioned above the main flow section, and a high-speed camera is positioned outside the transparent material body. The irradiation range of the laser and the imaging range of the high-speed camera both cover the internal channel region of the film cooling holes. The measurement method includes: introducing the main flow medium into the main flow section, introducing the cooling fluid into the film cooling holes, irradiating the flow field region inside the film cooling holes with a laser beam, and continuously acquiring images of the flow field region using the high-speed camera. Compared with existing technologies, this invention overcomes the optical limitations of traditional methods in measuring complex channels and near-wall regions, significantly improving the visualization and measurement level of the flow structure inside film cooling holes.

The invention relates to a one-dimensional pyrenyl organic framework nonlinear optical material as well as preparation and application thereof. The material is prepared from a pyrenyl amino monomer (Py) and different dialdehyde monomers (PTDE, PTBE and PDA) through direct Schiff base condensation reaction under a solvothermal condition, a series of one-dimensional linear organic framework material (COF) chain segments are constructed, and a thin film material is further prepared. The obtained material has highly ordered crystallinity, an expanded pi-conjugated skeleton and an obvious donor-acceptor (D-A) charge transfer channel. The one-dimensional pyrenyl D-A COF (Py-PTDE, Py-PTBE and Py-PDA) has the advantages that the one-dimensional pyrenyl D-A COF (Py-PTDE, Py-PTBE and Py-PDA) has the obvious RSA (Reverse Saturated Absorption) effect under the excitation of femtosecond laser (800 nm and 1550 nm) for the first time; compared with the prior art, in particular to a Py-PTDE material, the effective nonlinear absorption coefficient (beta eff) of the Py-PTDE material reaches 116.89 cm. GW <-1 > and 337.03 cm. GW <-1 > at 800 nm and 1550 nm respectively, so that the Py-PTDE material is obviously superior to a precursor material and another two COF materials, and shows a lower optical limiting threshold value at a near-infrared band. The excellent performance is mainly derived from more effective D-A interaction, narrower optical band gap and more efficient intramolecular charge transfer channel in the material. The material disclosed by the invention is simple in preparation method and high in repeatability, and the obtained COF film has excellent thermal stability and optical stability, can be directly used for preparing optical limiting devices and ultrafast optical response devices and can be applied to other three-order nonlinear optical fields.

The utility model relates to a GaN-based laser diode structure, which comprises a GaN substrate, an epitaxial layer is grown on the substrate, and the epitaxial layer comprises a lower covering layer, a lower waveguide layer, a quantum well, an upper waveguide layer, an electron blocking layer, an upper covering layer and an epitaxial contact layer which are sequentially arranged from bottom to top; an ohmic contact layer is arranged on the epitaxial layer, a metal covering layer is plated on the ohmic contact layer, a ridge structure close to a vertical angle is manufactured along the metal covering layer, the ohmic contact layer, the epitaxial contact layer and the upper covering layer, an insulating layer covers the ridge structure, an electron blocking layer covers the ridge structure, a P electrode covers the outer side of the insulating layer, and a substrate is thinned. And manufacturing an N electrode to form a laser diode structure. According to the utility model, ITO is used as an ohmic contact layer, and Pd is matched to be used as a photoetching mask plate; a right-angle surface is formed by utilizing a larger ITO lateral etching angle and combining with a Pd mask; good ohmic contact and a ridge structure close to a vertical angle can be formed, and a good optical limiting effect is achieved.

The present application belongs to the technical field of semiconductor optoelectronic device process, and relates to a manufacturing method of a semiconductor laser, which can realize beam shaping of a semiconductor laser element. The present application innovatively adopts a selected-area microprocessing technology to realize a selected-area optical limiting microstructure of a laser cavity surface through wafer pretreatment before cleaving of the cavity surface, eliminate cavity surface light emission, and improve beam quality. The greatest advantage of the present application is that the preparation of the selected-area optical limiting microstructure is completed before cleaving of the cavity surface, which can avoid cavity surface pollution and solve the far-field "square window" problem, improve product performance and production yield, and provide reliable technical support for commercial application.

The invention discloses a compound optical amplitude limiting structure based on stimulated Brillouin effect and a design method thereof, and relates to the technical field of laser amplitude limiting, the compound optical amplitude limiting structure comprises packaging protection layers which are sequentially arranged along the optical path direction, the packaging protection layers are made of neodymium-doped lithium yttrium fluoride glass, the packaging protection layers are in a rectangular flat plate shape, and the packaging protection layers are made of neodymium-doped lithium yttrium fluoride glass. Extending narrow edges are arranged on the two sides in the light path direction, so that a combined structure with a containing space is formed; the first optical amplitude limiting dielectric layer is made of CS2 liquid, and one side of the isolation layer is in contact with the surface of the first optical amplitude limiting dielectric layer; the second optical amplitude limiting dielectric layer is made of TeO2 crystals, and the compound optical amplitude limiting structure based on the stimulated Brillouin effect and the design method of the compound optical amplitude limiting structure solve the problem that in the prior art, a laser amplitude limiting material is difficult to give consideration to both high and low light transmittance and high light consumption rate at the same time. The compound optical amplitude limiting structure based on the stimulated Brillouin effect and the design method of the compound optical amplitude limiting structure based on the stimulated Brillouin effect solve the problem.

The invention provides a high-power low-intensity-noise semiconductor laser chip and a laser, a lower waveguide layer is arranged above an N-type substrate, two optical limiting layers are arranged above the lower waveguide layer, an active layer is clamped between the two optical limiting layers, a grating layer is arranged on the optical limiting layers, and the grating layer is arranged on the N-type substrate. An upper cladding layer is arranged on the grating layer, and a contact metal layer is arranged on the upper cladding layer; the grating layer is integrated with a lambda / 4 phase shift structure; and the semiconductor laser chip adopts a ridge waveguide structure. Compared with a traditional narrow ridge waveguide DFB laser, the narrow ridge waveguide DFB laser has the advantages that under the short cavity length condition, the output power exceeding hundreds of milliwatts, low relative intensity noise, high side mode rejection ratio and the narrow line width of about hundreds of kHz are achieved, and meanwhile the relaxation oscillation frequency of the GHz level is achieved. The laser chip shows good power linearity and single-mode stability in a lower normal temperature range, and is suitable for the fields of high-speed optical fiber communication, microwave photonics and the like with strict requirements on power and noise performance.

A glucose detection or monitoring system that includes a VCSEL laser with one or more active regions having quantum wells and barrier. The active regions are surrounded by one or more p-n junctions. The one or more active regions can include a selected shape structure, and one or more tunnel junctions (TJ). One or more apertures are provided with the selected shape structure, one or more buried tunnel junctions (BTJ) or oxide confine apertured, additional TJ's, planar structures and or additional BTJ's created during a regrowth process that is independent of a first growth process with a VCSEL output determined in response to a monitoring application of the VCSEL, the VCSEL having an HCG grating and a bottom DBR. A housing of a wearable device interior houses the VCSEL laser.

An electro-optic device comprising a waveguide (WG)-device configured as an electro-absorption modulator (EAM) and electronics comprising an EAM driver. The electro-optic device comprising: a semi-insulating (SI) indium phosphide (InP) substrate; an epitaxial layer stack formed on the SI:InP substrate comprising a first plurality of semiconductor layers forming InP heterojunction bipolar transistors of the electronics and a second plurality of semiconductor layers structured to form a PIN waveguide of the EAM, the PIN waveguide comprising: an n-layer structure and a p-layer structure; an i-region comprising optical material located between the n-layer structure and the p-layer structure; the n-layer structure and the p-layer structure configured to optical confine one or more modes of an optical signal configured to propagate through the i-region; and at least one of the n-layer structure and the p-layer structure comprises a mode extending layer.

The application relates to the technical field of semiconductor lasers, in particular to a high-speed communication vertical cavity surface emitting laser and a preparation method thereof. The tunnel junction is used to replace the traditional oxidation layer of the VCSEL, and is used for providing current limitation and optical limitation. 0.98 Ga 0.02 As controls the oxidation depth to realize current and optical limitation of the oxidation aperture, and the replacement of the tunnel junction structure can also avoid Al interface oxidation and can prevent further growth of defects. The replacement of the oxidation layer by the tunnel junction limitation structure can realize higher emission uniformity and higher repeatability in manufacturing, can accurately define the size of the oxidation aperture, and control the stability of the mode.

The application discloses copper oxide nanosheets, a preparation method and application thereof. The preparation method comprises the following steps: dispersing layered copper hydroxide acetate in an intercalation agent solution to perform ion exchange; adjusting the solution obtained after the ion exchange to be alkaline, and heating to reflux to obtain black precipitate; and washing and drying the black precipitate to obtain the copper oxide nanosheets. The method has mild conditions, and the copper oxide nanosheets prepared by the method have large lateral size and thin thickness, and can be well used in optical limiting devices.

The application discloses a continuous domain bound state laser based on a mixed cavity structure and a preparation method thereof. The laser comprises, from bottom to top along a vertical direction, a substrate, an optical confinement layer, an N-type interval layer, an active layer, a P-type interval layer, a photonic crystal layer and a current expansion layer. The optical confinement layer at the bottom and the photonic crystal layer at the top jointly form a vertical mixed resonant cavity, and the active layer is located in the resonant cavity and maintains an un-etched complete layered structure. The photonic crystal layer is provided with a periodic nano-pore array penetrating through and is configured to support a BIC mode. The application separates the gain medium and the optical field regulation structure physically, avoids etching damage of the active layer in a traditional process, and significantly reduces surface non-radiation recombination loss. Meanwhile, in combination with the current expansion layer design, efficient vertical heat dissipation and uniform electric injection of the device are realized, and the device has the advantages of low threshold, high single-mode stability and wavelength regulation and the like.

This application discloses a gallium nitride (GaN) laser and a method for improving its lateral modes based on an anti-waveguide. The method includes: processing the epitaxial structure of the GaN laser to remove a contact layer, a second optical confinement layer, and a portion of the second waveguide layer, thereby forming a ridge structure; and depositing a high-refractive-index thin film on at least a portion of the surface of the second waveguide layer surrounding the ridge structure to form an anti-waveguide structure. By forming the anti-waveguide structure in the GaN laser, this application enables modulation of the effective refractive index in regions other than the ridge structure, providing an effective means of modulating the effective refractive index difference between the ridge structure and the regions outside it. Furthermore, by adjusting the magnitude of this effective refractive index difference, the generation of more higher-order modes can be suppressed, reducing beam quality M. 2 This factor significantly improves the spot quality of gallium nitride lasers.

This invention discloses a photo-switching organoiridium metal complex, its preparation method, and its applications, belonging to the field of photoisomerization materials technology. This invention involves forming an N^N ligand through a Sonogashira coupling reaction between alkynyl spiropyran and phenanthroline, and finally coordinating with a bridging ligand to form a photo-switching organoiridium metal complex. This photo-switching iridium metal material combines nonlinear optical materials with photoisomerizing spiropyran molecules, exhibiting excellent optical limiting performance, good photothermal stability, photoisomerization characteristics, fatigue resistance, bleaching resistance, and excellent laser protection performance. Furthermore, after ultraviolet irradiation, the expansion of the complex's conjugation degree due to the ring-opening of the spiropyran molecule further enhances its laser protection performance.

A semiconductor optical amplifier and a fabricating method for a semiconductor optical amplifier. The semiconductor optical amplifier comprises, from bottom to top, an N-type electrode, an N-type substrate, a first passive waveguide layer, an N-type cladding layer, a first separated confinement heterostructure (SCH) layer, an active region, a second SCH layer, a first P-type cladding layer, a first P-type contact layer, and a P-type electrode, wherein the thickness of the first passive waveguide layer is less than 1 micron, and the width of the first passive waveguide layer is less than the width of the N-type substrate. By optimizing the thickness of the passive waveguide to regulate the optical confinement factor, a semiconductor optical amplifier having watt-level high saturation output power is achieved.

Some implementations described herein include a semiconductor laser having a distribution of a coupling coefficient. The semiconductor laser includes a substrate, and a semiconductor multilayer. The semiconductor multilayer includes an active layer, a grating layer, and an optical confinement adjustment layer which is flat. The semiconductor multilayer forms a first region and a second region. The optical confinement adjustment layer includes a high refractive index region, and a low refractive index region having a refractive index lower than a refractive index of the high refractive index region. The high refractive index region is arranged in any one of the first region or the second region and the low refractive index region is arranged in another one of the first region or the second region so that a first coupling coefficient of the first region becomes larger than a second coupling coefficient of the second region.

The invention discloses a continuous domain bound state laser based on a mixing cavity structure and a preparation method thereof. The laser sequentially comprises a substrate, an optical limiting layer, an N-type spacing layer, an active layer, a P-type spacing layer, a photonic crystal layer and a current expansion layer from bottom to top in the vertical direction. The optical confinement layer at the bottom and the photonic crystal layer at the top jointly form a vertical mixed resonant cavity, and the active layer is located in the resonant cavity and keeps an unetched complete layered structure. The photonic crystal layer is provided with a penetrating periodic nanopore array configured to support a BIC mode. According to the invention, the gain medium and the light field regulation and control structure are physically separated, so that the etching damage of the traditional process to the active layer is avoided, and the non-radiative composite loss of the surface is obviously reduced; and meanwhile, by combining the design of the current expansion layer, efficient vertical heat dissipation and uniform electric injection of the device are realized, and the device has the advantages of low threshold, high single-mode stability, adjustable wavelength and the like.

An optical amplifier having a front side, a back side, and an optical resonant cavity, the cavity having a length defined between the front side and the back side, the cavity including a waveguide having an optical confinement factor and a width defined transverse to the length of the cavity, the waveguide has an increasing width in a direction along the length of the cavity, and the optical confinement factor of the waveguide decreases in the direction along the length of the cavity in the portion of the cavity.

An electro-optic method and device fabricated with the metastable phase of BTO. The metastable tetragonal phase of BTO is preserved for optical confinement in active BTO by using direct wafer bonding on a cladding of thick SiO2.

The invention discloses a nonlinear optical limiter based on VO2 and a preparation method of the nonlinear optical limiter, and relates to a nonlinear optical limiter and a preparation method of the nonlinear optical limiter. The invention aims to solve the problems that a transmission switch of an existing optical amplitude limiter formed by a VO2 single film is small, the frequency band is wide and complex, and the high-power optical energy amplitude limiting requirement is difficult to meet. The optical limiter is sequentially composed of a transparent substrate, a VO2 layer and an ITO layer from bottom to top. And a plurality of cross-shaped holes are formed in the ITO layer in an array manner. The preparation method comprises the following steps: 1, forming an amorphous VO2 layer on a transparent substrate by using a magnetron sputtering or atomic layer deposition method, and then carrying out heat treatment to obtain a VO2 layer; 2, forming a continuous ITO (Indium Tin Oxide) layer on the VO2 layer by utilizing a magnetron sputtering or atomic layer deposition method; and 3, forming array cross holes in the continuous ITO layer by using a laser direct writing combined etching method. The invention is used for the VO2-based nonlinear optical amplitude limiting device and the preparation of the VO2-based nonlinear optical amplitude limiting device.