188 results about "External cavity" patented technology

The invention relates to the technical field of lasers, in particular to a multi-chip vertical external cavity surface emitting laser which comprises a chip set, a first prism, a second prism and an output coupling mirror which are sequentially arranged along a preset central axis. The chipset comprises N gain chips, and the N gain chips output N sub light beams; the N sub-beams pass through the first prism, the sub-beams emitted from the first prism converge towards a preset central axis, the sub-beams are incident to the second prism before convergence and are combined into a resonant beam through the second prism, the resonant beam resonates in a resonant cavity formed by the output coupling mirror and the chip set, and the output coupling mirror and the chip set form a resonant cavity; the output laser is emitted from the output coupling mirror; wherein N is greater than 1. The invention is beneficial for solving the problems that the power of a single chip is limited, the beam combining efficiency is low, only incoherent beam combining can be realized, and a multi-chip beam combining structure is complex.

The invention relates to the technical field of optoelectronic devices, in particular to a laser based on two different gratings and a metal grating with a phase interval of lambda / 2, which comprises a gain chip, a gain chip optical waveguide, an optical waveguide substrate, an optical waveguide, an annular resonant optical waveguide and a metal BRAGG reflecting grating. A unique outer cavity structure is adopted, a traditional interlayer semiconductor grating is abandoned, a top metal grating is adopted, a traditional DFB sandwich type secondary epitaxy manufacturing process is greatly simplified and avoided, the production cost is reduced, particularly, the metal grating is divided into two parts with similar but different grating constants, and the phase positions of the two gratings are pulled by lambda / 2, so that the performance of the DFB is improved. According to the design, the side mode rejection ratio (SMSR) of laser beams can be effectively improved, the laser line width is compressed, a guarantee is provided for stable work of the laser in a high-performance application scene, and the grating reflection efficiency is effectively improved by combining a'mouth-to-mouth 'coupling butt joint mode of the gain chip and the optical waveguide substrate.

The invention provides a broadband linear frequency modulation microwave source based on ultra-short external cavity modulation light feedback, and relates to the field of microwave photonics. Continuous light generated by the main semiconductor laser is injected into the slave laser after being adjusted, so that the slave laser works in a periodic oscillation state; the slave laser, the electro-absorption modulator and the reflector are integrated to form an ultra-short outer cavity, and the intensity of feedback light is regulated and controlled by an external signal source so as to realize linear scanning of cavity mode frequency. After beam splitting of light output from the laser, one path forms a long external cavity feedback stable signal through the adjustable optical fiber delay line, and the other path outputs a target signal after beat frequency of the photoelectric detector and filtering of the band-pass filter. A high-speed modulator and a high-frequency microwave source are not needed, the broadband advantage of a photonics scheme is reserved, the frequency sweeping bandwidth is further improved to 60 GHz or above, the center frequency and the frequency sweeping range are independently adjustable, the structure is simple, cost is low, integration is easy, and the device is suitable for scenes such as photoelectric radars.

This invention discloses a Littrow-type cavity length-compensated mode-hopping-free continuously tunable semiconductor laser, comprising a laser diode (1), a collimating lens (2), and a diffraction grating (3). Mode-hopping-free continuous tunability is achieved through a micro-elastic material base (4). The micro-elastic material base (4) is hollowed out to create a movable block (401) that can be driven by a piezoelectric ceramic (5), an isosceles triangular groove (404), and a pair of waist arms (406), enabling micro-displacement and micro-angle changes in the waist arms (406), thereby achieving continuous tunability of the output laser. This invention achieves mode-hopping-free continuous tunability of the laser output through an innovative combination of a special mechanical structure and the frequency selection characteristics of the grating. The structure is compact and highly stable, ultimately resulting in a mode-hopping-free continuously tunable external cavity semiconductor laser that meets the requirements of high-end precision measurement.

The application discloses a kind of parallel coupling self-imaging external cavity coherent array semiconductor laser, comprising: semiconductor laser chip array, light transmission dielectric layer and external cavity reflection layer;Semiconductor laser chip array includes multiple light emitting units, light transmission dielectric layer and external cavity reflection layer form laser self-imaging external cavity;The non-light emitting area of semiconductor laser chip array light emitting surface is coated with high reflection film, and the feedback light that cannot be injected into the light emitting unit due to incomplete self-imaging at the edge of semiconductor laser chip array can oscillate in self-imaging external cavity multiple times to reform the self-imaging that can be completely injected into the light emitting unit.The application improves the injection of laser outside the light emitting area, can efficiently parallel coupling all light emitting units including edge in chip array, eliminate the edge effect of chip array generated by self-imaging external cavity feedback, enhance the feedback efficiency of self-imaging external cavity, obtain the coherent array laser output of high parallel coupling efficiency, high efficiency optical mutual injection.

The invention discloses an optical fiber laser external cavity spectrum synthesis crosstalk elimination method, which relates to the technical field of laser, and comprises the following four steps of: firstly, designing and constructing a spectrum synthesis system model by taking a reflection-type volume Bragg grating (R-VBG) as a beam combiner, and blocking a crosstalk path through R-VBG wavelength selective transmission and diffraction and grid line vertical design; calculating an optimal grating parameter by combining R-VBG loss and diffraction efficiency correlation and multi-parameter internal relation; a steady-state rate equation is deduced based on a three-energy-level system, and a pumping threshold power change rule and an output characteristic expression are obtained; and finally analyzing the influence of light beam characteristics and thermal deformation on diffraction efficiency, determining a threshold value and controlling temperature, and verifying the system performance through experiments. The method can fundamentally eliminate crosstalk, guarantee the quality of the light beam, balance the cost and loss, adapt to a multi-channel scene, and have a remarkable application value in a multi-field high-power fiber laser.

We provide a cavity ring-down spectrometer that enables accurate measurement of extremely low-temperature samples. [Solution] The gas absorption spectrometer is a gas absorption spectrometer for measuring a sample gas and comprises a resonator 100A including at least two mirrors, a laser light source that emits laser light for irradiating the resonator 100A, and a photodetector for detecting the light extracted from the resonator. The resonator includes an inner chamber 1A that houses the mirrors 21 and 22 and forms a measurement space 15 into which the sample gas is introduced, an outer chamber 3A disposed outside the inner chamber 1A for vacuum insulation of the measurement space 15 from the outside, and a cooler 9 disposed within the outer chamber 3A, spaced apart from the inner chamber 1A, and having an internal space through which a refrigerant flows.

The invention provides a hybrid integrated semiconductor laser and a bandwidth increasing method, and relates to the field of optoelectronic devices. The hybrid integrated semiconductor laser comprises a semiconductor laser chip and a silicon nitride outer cavity chip, an optical feedback regulation and control structure is integrated in the silicon nitride outer cavity chip, active control over feedback light is achieved, photon-photon resonance and detuning loading effects are further introduced, and the modulation bandwidth of a directly modulated laser is cooperatively improved. The hybrid integrated semiconductor laser provided by the invention not only is simple in structure and high in preparation yield, but also can carry out secondary improvement on the bandwidth of a finished laser, and has the advantages of flexible regulation and control, easy integration and wide applicability.

This invention discloses a coaxial dual-cavity optical detection system, relating to the field of gas detection, which solves the problems of poor portability and low laser utilization in existing equipment. The system includes an air inlet, two coaxially arranged cavities with the inner cavity located inside the outer cavity, a vent, an outlet, a plano-concave mirror, and symmetrical window mirrors. The two cavities are interconnected through the vent, allowing for gas filling and exhaust with a single gas path. Coaxial parallel plano-concave mirrors are installed within the cavities, working in conjunction with an external reflector, convex lens, and detector to guide refracted light incident on the inner cavity into the outer cavity for utilization, forming a closed loop in the optical path of the two cavities. This system significantly reduces longitudinal and lateral dimensions, improving portability; simultaneous dual-cavity detection improves detection accuracy; the utilization of refracted light enhances laser utilization and sensing efficiency; and the increased effective optical path within a limited volume improves gas detection sensitivity, making it suitable for trace gas detection.

The invention discloses a high-performance optical comb laser based on heterogeneous material integration and multi-effect fusion, belongs to the technical field of optical communication and laser devices, and aims to solve the problems that a traditional optical comb laser is difficult to start tuning, low in power efficiency, large in line width or limited in bandwidth and the like. A scheme of heterogeneous integration of a III-V group gain material, a low-loss Si3N4 waveguide and a high-electro-optical coefficient barium titanate (BTO) material is adopted, an outer cavity chip comprises a high-Q-value annular resonant cavity, an electro-optical comb is generated by modulating the annular resonant cavity, then a Kerr comb is excited, and the optical comb is amplified through gain. According to the invention, three mechanisms of electro-optical modulation, Kerr effect and semiconductor light amplification are fused, and based on device topological structure innovation and unit device optimization, the problems are solved, the on-chip frequency comb performance is significantly improved, and the optical comb laser with excellent starting and tuning performance, high power, large bandwidth and narrow line width is realized.

A vertical cavity surface emitter (VCSEL) has a body comprising a vertical stack of stacked semiconductor layers, including: a current-limiting region enclosing a low-resistance current-flow region defined by a high-resistance current-flow region, and a first epitaxial sublayer located near the current-limiting region, wherein the first epitaxial sublayer includes a projection or recess defining a main cavity, and the remainder of the first epitaxial sublayer defines an outer cavity;wherein the projection or recess is defined by a physical step h which is predetermined according to the following equation: qλ0 - mλ1 = n0 h where λ0 is a resonant wavelength of the light in the main cavity, λ1 is a resonant wavelength of the light in the outer cavity, q is a positive half-integer, n0 is the effective refractive index in the main cavity, and m is a constant.;

A processing chamber includes a chamber body, a lid disposed over the chamber body, and one or more first laser devices disposed over the lid. The one or more first laser devices are configured to emit light having a wavelength of about 380 nm to about 600 nm. A first isolation plate is disposed within an internal volume that is at least partially defined by the chamber body. A semi-translucent layer is disposed over the first isolation plate. The semi-translucent layer configured to absorb at least part of the light emitted from the one or more first laser devices.

This invention provides a device and method for generating simultaneously emitted three wavelengths of laser light with equal spacing, relating to the field of laser technology. The device includes a pump source, a half-wave plate, an optical isolator, a focusing lens, an input mirror, a Raman crystal, an output mirror, a nonlinear crystal, and a dichroic mirror arranged sequentially along the optical path. The pump light, after its polarization direction is adjusted by the half-wave plate and the optical isolator, is focused onto the Raman crystal. Stimulated Raman scattering generates first and second Stokes beams, which are then converted to sum-frequency light by the sum-frequency effect of the nonlinear crystal. Finally, the dichroic mirror outputs three equally spaced wavelengths of laser light. This invention separates the Raman conversion and sum-frequency processes through an external cavity structure, achieving for the first time the simultaneous emission of three equally spaced wavelengths of laser light, offering advantages such as high output energy, equal wavelength spacing, and simultaneous emission of three wavelengths.

The utility model provides a double-cavity structure and PEALD equipment thereof, and relates to the technical field of coating equipment. Comprising an outer cavity and an inner cavity mounted in the outer cavity; wherein the inner cavity is internally provided with a carrying table suitable for placing a wafer carrying disc; and the inner cavity is suitable for being connected with a reaction source so as to finish a coating process in the inner cavity. Through the scheme, the film thickness uniformity can be improved, the independence of a reaction region is realized, the precursor utilization rate is improved, and the maintenance process is simplified.

The utility model discloses PECVD (Plasma Enhanced Chemical Vapor Deposition) equipment, and belongs to the field of photovoltaic technology. The PECVD equipment comprises a base, a first electrode, a second electrode and a third electrode, wherein the base forms an outer cavity; the multiple cooling devices are vertically stacked and installed in the outer cavity, each cooling device comprises a supporting piece and a cooling tower installed on the supporting piece, and every two adjacent cooling towers are connected in a matched mode through the corresponding two sets of supporting pieces in the vertical direction; and the guide piece is installed in the outer cavity and forms a guide groove, the extending direction of the guide groove is parallel to the stacking direction of the multiple cooling devices, and the supporting piece is in sliding fit with the guide groove. Through the arrangement of the guide piece, the butt joint deviation caused by space limitation is obviously reduced, the hoisting precision and stability are improved, the free movement of the cooling device in the hoisting process is limited, and the shaking of the inner cavity in the hoisting process is reduced, so that the collision damage of internal parts of the inner cavity in the hoisting process is reduced.

The invention discloses a graphene strain structure and a preparation method and application thereof. The structure comprises a structure substrate layer, a step cavity array, a graphene absorption layer, a flexible strain layer, a dielectric layer and a lower electrode layer. The step cavity array comprises a plurality of step cavities arranged on the structure substrate layer, each step cavity sequentially comprises an outer cavity and an inner cavity from an opening to the inside, a step surface is formed between the outer cavity and the inner cavity, and the transverse size of the outer cavity is larger than that of the inner cavity; the graphene absorption layer is arranged on the step surface of each step cavity; the flexible strain layer is attached to the outside of the step cavity array and seals the opening of each step cavity, and a film side electrode layer is deposited on one side, back to the step cavities, of the flexible strain layer; the flexible strain layer and the lower electrode layer are separated and fixed by the dielectric layer, so that the film side electrode layer and the lower electrode layer form a capacitor; the invention also discloses a preparation method of the graphene strain structure. The device is suitable for wide-spectrum electromagnetic energy detection and conversion, and is easy for large-area integration and large-scale manufacturing.

A Vertical Cavity Surface-Emitting Laser (VCSEL) has a body comprising a vertical stack of semiconductor layers one on top of the other, including: a current confinement region including an area of low resistance to current flow defined by an area of high resistance to current flow, and a first epitaxial sublayer disposed proximate to the current confinement region, the first epitaxial sublayer including a protrusion or a recess defines a main cavity, and the balance of the first epitaxial sublayer defines an outer cavity; wherein the protrusion or recess is defined by a physical step h that is predetermined according to the equation: qλ0−mλ1=n0h where λ0 is resonant wavelength of light in the main cavity, λ1 is resonant wavelength of light in the outer cavity, q is a half-integer positive number, n0 is effective refractive index in the main cavity, and m is a constant.

The invention relates to the technical field of optics, and discloses a device for generating a one-dimensional light spot array and a device for generating a two-dimensional light spot array, and the device for generating the one-dimensional light spot array comprises a laser module which is used for generating a plurality of first light beams with different wavelengths, and generating positions of any two first light beams with different wavelengths have a mutual injection phenomenon, any two first light beam generation positions with different wavelengths also generate mutual injection light beams; the transmission-type grating is used for synthesizing the first light beams with different wavelengths into a target light beam and transmitting a mutual injection light beam; the external cavity reflecting mirror is used for reflecting one part of the target light beam and transmitting the other part of the target light beam, and is used for reflecting one part of the mutual injection light beam and transmitting the other part of the mutual injection light beam; and the first lens is used for focusing the transmitted target light beam and the transmitted mutual injection light beam to form discrete light spots arranged along a first direction array. According to the invention, the one-dimensional light spot array with uniform energy distribution and uniform light spot size can be generated, and the cost is low.

The application discloses an external cavity semiconductor chaotic laser, which comprises a driving source, a temperature control unit and an output assembly; the temperature control unit comprises a TEC controller, a TEC refrigerating sheet and a temperature sensor which are located inside a butterfly-shaped package; a semiconductor gain medium, a coupling lens group, an external cavity reflector and a collimating lens group are fixedly installed on the TEC refrigerating sheet in sequence along the outgoing direction of laser; the semiconductor gain medium, the coupling lens group and the external cavity reflector are coupled in sequence to form a laser resonant cavity; the electrodes of the temperature sensor and the TEC refrigerating sheet are connected with the TEC controller through the pins of the butterfly-shaped package respectively; the electrodes of the semiconductor gain medium are connected with the driving source through the pins of the butterfly-shaped package; and the output assembly is located right behind the output end of the collimating lens group. The laser of the application has the advantages of simple structure, low cost, easy operation, good environmental adaptability and stable high-quality chaotic laser output.

A method of making a readout mirror for a ring laser gyroscope comprises forming an optical substrate component that includes a lower surface, a first upper surface portion substantially parallel to the lower surface, and a second upper surface portion angled with respect to the lower surface; performing a coarse polish of the second upper surface portion; forming an optical part having a first surface; performing a super polish of the first surface of the optical part; applying a first beam splitter layer to the super polished first surface of the optical part, to produce a beam splitter side of the optical part; and bonding the beam splitter side of the optical part, using an optical adhesive, to the coarse polished second upper surface portion of the substrate component, to produce a reflector member. The reflector member is configured to reduce external cavity light scattering in the ring laser gyroscope.

The application relates to a coaxial relativistic magnetron outputting TEM modes, belonging to the technical field of high-power microwaves, which comprises an anode, a cathode and a magnet, the anode comprises an inner cavity cylinder and an outer cavity cylinder which are coaxially nested, long anode blocks and short anode blocks are alternately arranged on the inner wall of the inner cavity cylinder in the angular direction, the long anode blocks and the short anode blocks are alternately distributed in the axial direction of the inner cavity cylinder to form symmetrical sector edge cavities inside the inner cavity cylinder, an edge cavity angular coupling slot is arranged on the inner cavity cylinder and corresponds to the sector edge cavities, and an inner cavity axial coupling slot is arranged on the inner cavity cylinder and located between the long anode blocks and the short anode blocks, the application has the advantages of simple and compact structure, suitable permanent magnet packaging and low-order mode output, and can realize high-power and high-efficiency microwave output.

A light source for a frequency-modulated continuous-wave (FMCW) LiDAR device is formed by a photonic integrated circuit and comprises a substrate and a multilayer structure. Formed in the multilayer structure is a semiconductor laser that is received in a recess etched into the multilayer structure. An optical path between the semiconductor laser and a reflector forms an external cavity for the semiconductor laser. The external cavity includes a variable attenuator causing an attenuation of light guided in the cavity optical waveguide. The external cavity may also or alternatively include an optical phase modulator.

The invention relates to the technical field of semiconductor lasers, in particular to a laser based on a bimetallic Bragg grating and a top surface HR reflecting film, which comprises a gain chip, a first high-reflection HR film is plated on the left end surface of the gain chip, and a first anti-reflection AR film is plated on the right end surface of the gain chip. A metal Bragg grating waveguide is arranged on the right side of the gain chip, the right end face of the gain chip and the left end face of the metal Bragg grating waveguide are aligned and attached to form an outer cavity structure, and the left end face of the metal Bragg grating waveguide is plated with a second anti-reflection AR film. The right end face of the metal Bragg grating waveguide is plated with a third anti-reflection AR film. Performance test is carried out on the laser provided by the invention, and test results show that the line width is 0.6 kHz, the SMSR is 63dB, and the threshold current is 22mA, thereby verifying the effectiveness of the laser provided by the invention.

The invention relates to a flexible design method of refractive index constraint in an overgrowth-based vertical cavity surface emitting laser. A vertical cavity surface emitting laser (VCSEL) has a body including a vertical stack of semiconductor layers one above the other, including a current confinement region including a region of low resistance to current flow defined by a region of high resistance to current flow, and a first epitaxial sub-layer disposed proximate to the current confinement region, comprising protrusions or depressions defines a main cavity, and the remainder of the first epitaxial sub-layer defines an outer cavity; wherein the protrusions or recesses are defined by a physical step h predetermined according to the following formula: q [lambda] 0-m [lambda] 1 = n0h, where [lambda] 0 is the resonant wavelength of light in the main cavity, [lambda] 1 is the resonant wavelength of light in the outer cavity, q is a positive half integer, n0 is the effective refractive index in the main cavity, and m is a constant.

The invention relates to a coaxial relativistic magnetron for outputting a TEM mode, and belongs to the technical field of high-power microwaves, the coaxial relativistic magnetron comprises an anode, a cathode and a magnet, the anode comprises an inner cavity cylinder and an outer cavity cylinder which are coaxially nested, and long anode blocks and short anode blocks are alternately arranged on the inner wall of the inner cavity cylinder in the angular direction; the long anode blocks and the short anode blocks are alternately distributed in the axial direction of the inner cavity cylinder in a long-short mode so that symmetrical fan-shaped side cavities can be formed in the inner cavity cylinder, side cavity angular coupling seams are formed in the positions, corresponding to the fan-shaped side cavities, of the inner cavity cylinder, and inner cavity axial coupling seams are formed in the positions, located between the long anode blocks and the short anode blocks, of the inner cavity cylinder. The invention has the advantages of simple and compact structure, suitability for permanent magnet packaging and low-order mode output and the like, and can realize high-power and high-efficiency microwave output.

The application discloses a BP-3 tail material processing equipment, which comprises a support, a rotating frame rotatably arranged on the support, a tank rotatably arranged on the rotating frame, a collecting disc fixed in the support and arranged directly below the tank when the rotating frame rotates to be vertical, an inner cavity and an outer cavity separated by an inner pipe in the tank, an inner outlet and an outer outlet respectively arranged on the bottom of the inner cavity and the outer cavity and located on the same straight line, an inner liquid inlet and an outer liquid inlet respectively arranged on the bottom of the inner cavity and the outer cavity, a feeding port arranged on the top of the inner cavity, a feeding cover detachably arranged on the feeding port, and multiple partition plates arranged in the middle of the inner cavity. Compared with the prior art, the layered liquid is not mixed when flowing, and the production efficiency is high.

The present application provides a process chamber and a thin film deposition method. The process chamber comprises: an inner cavity, comprising a cylindrical non-metallic sidewall and a cylindrical antenna, the cylindrical non-metallic sidewall is located below the cylindrical antenna and forms a cylindrical sidewall of the inner cavity together with the cylindrical antenna, wherein the top wall of the cylindrical antenna is a planar structure; a shower plate arranged on the inner side of the cylindrical sidewall as the top wall of the inner cavity; a deposition table arranged on the inner side of the cylindrical sidewall as the bottom wall of the inner cavity, wherein at least one of the shower plate and the deposition table is lifted on the inner side of the cylindrical sidewall to adjust the volume of the inner cavity; and an outer cavity fixedly installed on the outer side of the inner cavity and forming a microwave transmission channel with the inner cavity.

The invention discloses a hybrid integrated external cavity frequency modulation continuous wave laser. The laser is formed by hybrid integration of a gain chip and a silicon optical chip. An on-chip filter device, an on-chip wavelength locking device, an on-chip frequency selection device and an on-chip light splitting device are integrated on the silicon optical chip; the on-chip filter device is composed of an outer cavity phase region and a micro-ring resonance device. The micro-ring resonance device is composed of two or more micro-rings with slightly different perimeters. The outer cavity phase region and each micro-ring are provided with two groups of heaters for phase change, and one group of heaters in the outer cavity phase region and each micro-ring is used for adjusting the bias of each device; and the other group of heaters are connected in series or in parallel through on-chip electric connecting wires, and a frequency sweeping signal is applied to realize frequency sweeping of the laser. One heater for laser cavity phase adjustment and one heater corresponding to filter adjustment are connected in series or in parallel, synchronous change of a laser cavity mode and a filter spectrum is achieved, the frequency sweeping range of the laser is expanded, and it is guaranteed that the laser can be basically unchanged during frequency sweeping.

The application relates to the technical field of semiconductor lasers, in particular to a laser based on a double-metal Bragg grating and a top SiO2 waveguide layer, which comprises a gain chip, the left end face of the gain chip is coated with a first high-reflection (HR) film, and the right end face of the gain chip is coated with a first antireflection (AR) film; a metal Bragg grating waveguide is arranged on the right side of the gain chip, the right end face of the gain chip is aligned and attached to the left end face of the metal Bragg grating waveguide to form an external cavity structure, the left end face of the metal Bragg grating waveguide is coated with a second antireflection (AR) film, and the right end face of the metal Bragg grating waveguide is coated with a third antireflection (AR) film. The application is subjected to a temperature change test, wavelength drift is controlled within the range of -40 DEG C to 85 DEG C, and is controlled within the range of -40 DEG C to 85 DEG C; performance test results show that the line width is 0.6 kHz, the SMSR is 65 dB, and the threshold current is 22 mA.

The invention relates to a flow uniformizing plate for semiconductor plating, a plating device and a plating solution bubble discharging method, the flow uniformizing plate is suitable for being arranged in a cavity of plating equipment, the cavity is divided into an inner cavity and an outer cavity, and the flow uniformizing plate is provided with a lower end face facing the inner cavity and an upper end face facing the outer cavity. The flow uniformizing plate comprises a first area, a second area and a third area, the first area is located in the middle of the flow uniformizing plate, and a plurality of flow uniformizing holes distributed at intervals are formed in the first area; the second area is located on the periphery of the flow uniformizing plate and provided with overflow holes. The inner cavity is communicated with the outer cavity through the flow uniformizing hole and the overflow hole; the third area is located between the first area and the second area, a first bubble guide structure is arranged on the lower surface of the third area, and the first bubble guide structure is configured to guide bubbles on the lower surface of the third area to enter the overflow hole in the process of injecting the plating solution into the inner cavity. And the bubble discharging effect can be effectively ensured by utilizing the guiding effect of the first bubble guiding structure on the bubbles.