A laser module and an epilator

Abstract

The application relates to the technical field of epilators, and particularly discloses a laser module and an epilator, the laser module comprising: a substrate, the substrate having a first surface; laser chips, the laser chips being arranged on the first surface and in a plurality, the plurality of laser chips being arranged at intervals along a first direction; and an electric connecting piece, the electric connecting piece being arranged between the laser chips and the first surface, the electric connecting piece comprising a plurality of first conductive sheets arranged at intervals along the first direction, and any first conductive sheet being electrically connected with one laser chip, the first conductive sheet having a protruding part and a notch, the laser chip being located on the protruding part, and the protruding part of one first conductive sheet being arranged at intervals in the notch of the adjacent first conductive sheet. The laser module and the epilator can help to reduce the structural volume.

Description

Technical Field

[0001] This invention relates to the field of hair removal technology, and in particular to a laser module and hair removal device. Background Technology

[0002] In existing laser modules, such as Chinese Patent Publication No. CN107863337A, a light-emitting device packaging structure is disclosed. In this structure, both the light-emitting diode (LED) chip and the electrode layer are disposed on the front side of a substrate. The LED chip is connected to an external power supply via the electrode layer. Specifically, the electrode layer includes a first electrode portion, a connecting portion, and a second electrode portion that are electrically connected in sequence. One LED chip is connected to the first electrode portion, and another LED chip is connected to the second electrode portion, thus achieving series connection of the two LED chips.

[0003] Therefore, the existing technology has at least the following problems: multiple light-emitting diode chips need to be connected in series with multiple electrode layers and connected to an external power source. The connection part of the electrode layer occupies the front space of the substrate, resulting in a large gap between multiple laser chips and increasing the volume of the structure. Summary of the Invention

[0004] The purpose of this invention is to provide a laser module and hair removal device that helps to reduce structural volume.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a laser module, comprising: A substrate having a first surface; Laser chips, wherein multiple laser chips are disposed on the first surface and are arranged at intervals along a first direction; and An electrical connector is disposed between the laser chip and the first surface. The electrical connector includes a plurality of first conductive sheets arranged at intervals along the first direction, and each first conductive sheet is electrically connected to a laser chip. The first conductive sheet has a protrusion and a notch, and the laser chip is located in the protrusion. The protrusion of one first conductive sheet is spaced in the notch of an adjacent first conductive sheet.

[0006] In some embodiments, the spacing between two adjacent laser chips and the spacing between two adjacent first conductive sheets are both equal, which satisfies 0.1mm≤a≤0.3mm.

[0007] In some embodiments, the laser chips are connected in series via the first conductive sheet.

[0008] In some embodiments, the laser chip has leads, the output end of the laser chip is electrically connected to its corresponding first conductive plate, and the input end of the laser chip is electrically connected to another adjacent first conductive plate via leads.

[0009] In some embodiments, the protrusion and the notch are located on one side of the first conductive sheet along the second direction and are arranged sequentially along the first direction, the lead is located on one side of the laser chip along the second direction and extends along the second direction, the second direction being perpendicular to the first direction.

[0010] In some embodiments, in the first direction, one side of the first conductive sheet is formed with a protrusion protruding in the first direction, and the other side of the first conductive sheet is formed with a notch recessed in the first direction. The laser chip is provided with leads on both sides opposite to each other in the second direction, and the leads extend in the second direction, which is perpendicular to the first direction.

[0011] In some embodiments, the electrical connector further includes a second conductive sheet and a third conductive sheet, wherein the output end of the second conductive sheet is electrically connected to the input end of the laser chip at the outermost end along one end of the first direction, and the input end of the third conductive sheet is electrically connected to the output end of the laser chip at the outermost end along the other end of the first direction.

[0012] In some embodiments, the electrical connector further includes a first terminal and a second terminal, the first terminal being electrically connected to the input terminal of the second conductive sheet, and the second terminal being electrically connected to the output terminal of the third conductive sheet.

[0013] In some embodiments, the first terminal has a first threaded hole and the second terminal has a second threaded hole.

[0014] In some embodiments, the laser module further includes a light-transmitting plate, which covers the electrical connector and the side of the laser chip facing away from the first surface. The input end of the second conductive sheet and the output end of the third conductive sheet are located outside the light-transmitting plate and are used for electrical connection with an external power supply.

[0015] In some embodiments, the light-transmitting plate has a receiving groove on the side near the first surface, and the laser chip is housed in the receiving groove.

[0016] In some embodiments, the light-transmitting panel is integrally formed, and its light-transmitting surface is covered with an anti-reflective film.

[0017] In some embodiments, the laser module further includes a heat spreader, and the substrate further has a second surface disposed opposite to the first surface, the heat spreader being located on the second surface of the substrate.

[0018] In some embodiments, the substrate is a ceramic substrate, the second surface of the substrate has a copper-clad layer, and the heat spreader is soldered to the copper-clad layer.

[0019] In some embodiments, the laser module further includes a temperature sensor located on the first surface.

[0020] In a second aspect, the present invention provides a hair removal device, including the laser module described in the first aspect.

[0021] This invention provides a laser module and hair removal device, which have the following advantages compared with the prior art: Each first conductive sheet in the laser module is electrically connected to a laser chip. The first conductive sheet has a protrusion and a notch, with the laser chip located on the protrusion. The protrusion of one first conductive sheet is spaced apart from the notch of an adjacent first conductive sheet, allowing for a compact arrangement of multiple first conductive sheets, and consequently, multiple laser chips. Specifically, the multiple first conductive sheets form a similar interlocking arrangement. This arrangement allows for a tight arrangement of multiple first conductive sheets without additional connecting parts or transition areas, while the gap between the protrusion and the notch provides electrical isolation, preventing short circuits. Because the compact arrangement of the first conductive sheets directly leads to a tight arrangement of the laser chips on them, the size of the first surface of the substrate can be reduced, decreasing the overall structural volume of the laser module. Ultimately, the hair removal device using this laser module can further reduce its overall size, improve convenience, and overcome the shortcomings of existing technologies where the space occupied by the electrode layer's connecting parts results in a less compact structure. Attached Figure Description

[0022] Figure 1 An exploded view of a laser module provided for some embodiments of the present invention.

[0023] Figure 2 This is an isometric view of a laser module provided for some embodiments of the present invention.

[0024] Figure 3 This is a first assembly diagram of an electrical connector and a laser chip for a laser module, provided for some embodiments of the present invention.

[0025] Figure 4 for Figure 3 An enlarged view of the assembly of two adjacent first conductive sheets.

[0026] Figure 5 This is a second assembly diagram of an electrical connector and a laser chip for a laser module, provided for some embodiments of the present invention.

[0027] Figure 6 for Figure 5An enlarged view of the assembly of two adjacent first conductive sheets.

[0028] Figure 7 This is an enlarged view of the light-transmitting plate of a laser module provided in the second embodiment of the present invention.

[0029] In the figure: 100, laser module; 1, substrate; 1a, first surface; 1b, second surface; 2, electrical connector; 21, first conductive sheet; 211, protrusion; 212, notch; 22, second conductive sheet; 23, third conductive sheet; 24, first terminal; 24a, first threaded hole; 25, second terminal; 25a, second threaded hole; 3, laser chip; 31, lead wire; 4, light-transmitting plate; 4a, receiving groove; 5, heat spreader; 6, temperature sensor; x, first direction; y, second direction. Detailed Implementation

[0030] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0031] It should be understood that in the description of this application, the terms "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. That is, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, unless otherwise stated, "a plurality of" means two or more.

[0032] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0033] like Figure 1 , Figure 4 and Figure 6 As shown, the laser module 100 of this embodiment includes a substrate 1, an electrical connector 2, and a laser chip 3. The substrate 1 is used to support and mount the electrical connector 2, which is used to electrically connect the laser chip 3 to an external power supply.

[0034] The substrate 1 has a first surface 1a and a second surface 1b facing away from each other. The substrate 1 serves both as a mechanical support and as a heat dissipation channel. Specifically, the first surface 1a supports the electrical connector 2, and the heat generated by the laser chip 3 is transferred to the first surface 1a through the electrical connector 2 and ultimately introduced into the interior of the substrate 1. The second surface 1b serves as a heat dissipation output surface, used to conduct the internal heat of the substrate 1 to external heat dissipation elements or cooling elements, thereby rapidly dissipating the heat.

[0035] Multiple laser chips 3 are disposed on the first surface 1a and are arranged at intervals along the first direction x. This improves the output energy of the laser module 100 and optimizes the beam uniformity, with the multiple laser chips 3 forming a continuous linear light-emitting region along the first direction x. The single-row, closely arranged, and series-connected structure offers advantages in beam uniformity and optical power density. For example, when considering beam uniformity, only the distance between two adjacent laser chips 3 along the first direction x needs to be considered, eliminating the need to consider or adjust multiple different directions simultaneously and reducing the need for complex optical processing components.

[0036] In this embodiment, since the multiple laser chips 3 are arranged only along the first direction x, the resulting light-emitting area is a long line light source with high beam uniformity. Even without additional optical lenses for shaping, it can project a linear beam with good uniformity onto the near-field working surface, achieving a uniform light effect. This is in contrast to the prior art's array-style arrangement of the laser chips 3 (e.g., rectangular or ring arrays). Array-style arrangements require multi-directional lens groups behind the light source for optical path correction and homogenization, significantly increasing the material cost and assembly precision requirements of components such as lenses. Furthermore, the uniform light performance often deteriorates due to assembly errors. In this embodiment, the multiple laser chips 3 are arranged in a single, closely spaced row, eliminating the need for additional optical lenses to achieve uniform light, thus reducing production costs and process complexity.

[0037] Furthermore, the close arrangement of multiple laser chips 3 in a single row reduces the overall emitting area of ​​the light source, concentrating the light emitted by all laser chips 3 within a narrower linear region. At the same total output optical power, a smaller emitting area means a higher optical power density per unit area. High optical power density helps reduce the overall size of the product, making the laser module 100 suitable for use in space-constrained, energy-density-critical miniaturized devices. Conversely, an array arrangement significantly increases the total emitting area, resulting in a significant decrease in optical power density per unit area, making it difficult to use in space-constrained scenarios. Directly focusing and homogenizing through a lens not only complicates the manufacturing process but also increases manufacturing costs.

[0038] Therefore, this embodiment utilizes a structure in which multiple laser chips 3 are arranged in a single column along the first direction x and connected in series. With the heat dissipation effect of the substrate 1, it not only meets the requirements of high light power density and good light spot uniformity, but also eliminates the need for additional optical lens structures. This makes the overall structure of the laser module 100 more compact and the cost lower, making it suitable for the field of portable hair removal devices where size, cost and energy density are all important considerations.

[0039] For example, the laser chip 3 is a VCSEL chip (vertical cavity surface emitter laser chip), and the direction of its laser emission is perpendicular to the first surface 1a.

[0040] An electrical connector 2 is disposed between the laser chip 3 and the first surface 1a, and includes a plurality of first conductive sheets 21 arranged at intervals along the first direction x, wherein each first conductive sheet 21 is electrically connected to a laser chip 3. Specifically, the plurality of first conductive sheets 21 are disposed on the first surface 1a of the substrate 1 to realize the electrical connection between the plurality of laser chips 3.

[0041] Furthermore, the first conductive sheet 21 has a protrusion 211 and a notch 212. The laser chip 3 is located in the protrusion 211, and the protrusion 211 of one first conductive sheet 21 is spaced apart in the notch 212 of an adjacent first conductive sheet 21. In this way, two adjacent laser chips 3 are brought close together in the first direction x, making the structure more compact.

[0042] Based on the above structural configuration, the multiple first conductive sheets 21 are arranged in a similar interlocking pattern. This arrangement allows the multiple first conductive sheets 21 to be tightly arranged without additional connecting parts or transition areas. Simultaneously, the gap between the protrusions 211 and the notches 212 provides electrical isolation, preventing short circuit risks. Because the compact arrangement of the first conductive sheets 21 directly leads to a compact layout of the laser chip 3 on them, the size of the first surface 1a of the substrate 1 can be reduced, thus decreasing the overall structural volume of the laser module 100. Ultimately, the hair removal device using this laser module 100 can further reduce the overall size of the device, improve convenience, and overcome the shortcomings of existing technologies where the space occupied by the electrode layer's connecting parts results in a less compact structure.

[0043] like Figure 4 and Figure 6As shown, in some embodiments, the spacing between two adjacent laser chips 3 and the spacing between two adjacent first conductive sheets 21 are both 'a', satisfying 0.1mm ≤ a ≤ 0.3mm. If a < 0.1mm, the insulation spacing of the first conductive sheets 21 will be insufficient: the first conductive sheets 21 typically carry drive current or high-speed pulse signals, and even in a clean packaging environment, the withstand voltage of the air or insulating medium between the first conductive sheets 21 will significantly decrease, easily leading to leakage or even short circuit; it will also cause a decrease in the yield of laser chip 3 mounting equipment, resulting in increased costs. If a > 0.3mm, the integration density of the laser chips 3 decreases, failing to meet compact requirements, and the spacing between the light emission centers of adjacent laser chips 3 becomes too large, leading to optical non-uniformity and increased package volume; it will also increase the spacing of the first conductive sheets 21, resulting in a larger parasitic inductance in the circuit.

[0044] It should be noted that in conventional laser chip array packaging, the spacing between adjacent laser chips and adjacent conductive sheets is often limited to 5 mm to 10 mm due to the operating space required for wire bonding. This value is much larger than the 0.1 mm–0.3 mm range proposed in this application, resulting in a small number of chips per unit area, low optical power density, and a large parasitic inductance in the circuit.

[0045] In this embodiment, by reducing the spacing 'a' to 0.1 mm–0.3 mm and employing a structure in which the laser chips 3 and the first conductive sheet 21 are arranged synchronously at equal intervals, the number of laser chips 3 per unit area is increased, the optical power density of multiple laser chips 3 per unit area is improved, and the trace length between the laser chips 3 is shortened. This reduces parasitic inductance, lowers switching losses, improves power efficiency, and suppresses electromagnetic interference. Furthermore, the uniform and small spacing 'a' makes the light emission points of multiple laser chips 3 approximately continuous line light sources, eliminating the need for additional optical lens structures.

[0046] like Figure 4 and Figure 6As shown, in some embodiments, the laser chips 3 are connected in series via the first conductive sheet 21. Specifically, the negative terminal of a laser chip 3 is electrically connected to its corresponding first conductive sheet 21, and the positive terminal of a laser chip 3 is electrically connected to its adjacent first conductive sheet 21, or to the positive terminal of an external power supply. In this way, all laser chips 3 form a series loop with a single current path through the first conductive sheet 21. In the series configuration, the driving current of all laser chips 3 is the same, the heat distribution of the laser chips 3 is uniform, and the series path of the first conductive sheet 21 forms a low-inductance loop. If a parallel structure is used, the current distribution among the laser chips 3 is easily unbalanced, making current sharing difficult and prone to thermal runaway of a single laser chip 3; the total current is large, the first conductive sheet 21 is prone to overcurrent and melting, and the parallel circuit usually needs to split into multiple paths from the external power supply to each laser chip 3. Even with a planar bus, it is impossible to avoid introducing additional parasitic inductance with a small spacing. These parasitic inductances will delay the current rise time and cause asynchronous current change rates among the laser chips 3, generating electromagnetic interference.

[0047] like Figure 4 and Figure 6 As shown, to achieve series connection between laser chips 3, laser chip 3 has a lead 31. The output terminal (negative electrode) of laser chip 3 is electrically connected to its corresponding first conductive sheet 21. Specifically, laser chip 3 and its corresponding first conductive sheet 21 are connected through a conductive connection layer, for example, the conductive connection layer is made of gold-tin solder or conductive silver paste. The input terminal (positive electrode) of laser chip 3 is electrically connected to another adjacent first conductive sheet 21 through the lead 31.

[0048] Correspondingly, for the first laser chip 3 arranged along the first direction x, its input end can be electrically connected to the second conductive sheet 22 via lead 31; for the last laser chip 3, its output end is directly soldered to the third conductive sheet 23, or soldered to its corresponding first conductive sheet 21, and then connected to the third conductive sheet 23 via lead 31 from the first conductive sheet 21. Thus, multiple laser chips 3 still form an electrical circuit connected in series, and the driving current flows through each laser chip 3 in sequence.

[0049] Specifically, the lead wire 31 is made of gold, aluminum, copper, or silver alloy wire, and is bonded using ultrasonic ball bonding or wedge bonding processes. The output end of the laser chip 3 is typically a large-area electrode on its bottom surface. Directly welding the output end of the laser chip 3 onto the first conductive sheet 21 not only achieves lower contact resistance but also allows the heat generated by the laser chip 3 to be conducted to the first conductive sheet 21 via the shortest path, and then to the first surface 1a of the substrate 1, retaining the advantages of efficient heat dissipation in the single-row arrangement. The input ends of the laser chips 3 are interconnected through flexible lead wires 31, which can absorb the height deviation and flatness error of the laser chip 3 during assembly, reducing the requirements for equipment precision and improving production yield. At the same time, the lead wires 31 occupy a small area and do not increase the spacing between the laser chips 3, thus maintaining the high optical power density and excellent spot uniformity required for the single-row close arrangement.

[0050] The output end of the laser chip 3 is directly soldered, and the input end is bonded with leads 31, which simplifies the graphic structure of the electrical connector 2 and makes the installation and replacement of each laser chip 3 independent, facilitating later repairs. The entire electrical connector 2 can still form a second conductive sheet 22, multiple first conductive sheets 21, and a third conductive sheet 23 on the first surface 1a of the substrate 1 through a single metallization process, and then uniformly mount and bond the laser chips 3, making it suitable for mass production.

[0051] When multiple laser chips 3 are arranged in a single row, the connection of the lead wire 31 presents the following problems: If the lead wire 31 of one laser chip 3 passes through the light-emitting surface of another adjacent laser chip 3 and the first conductive plate 21 from above, the lead wire 31 will block the light-emitting surface of the laser chip 3, causing loss of emitted light power and beam distortion. Furthermore, the laser irradiation of the lead wire 31 will raise the temperature, posing a risk of ablation and breakage. Alternatively, if the lead wire 31 of one laser chip 3 passes around the adjacent laser chip 3 and the first conductive plate 21 from the side, the lead wire 31 needs to be tilted to pass around the other laser chip 3. The length of the lead wire 31 will be lengthened, increasing the space occupied, destroying the compactness of the single row arrangement, and increasing the resistance, heat generation, and power consumption.

[0052] In this embodiment, the input terminal of each laser chip 3 is electrically connected to its adjacent first conductive sheet 21 via a lead 31. Specifically, the input terminal lead 31 of the current laser chip 3 extends in the second direction y and is directly bonded to the pad area of ​​the adjacent first conductive sheet 21 located on the side of the notch 212. Since the two adjacent first conductive sheets 21 are already staggered in the second direction y, the lead 31 can complete the bridging along a shorter straight path parallel to the second direction y, without having to pass over the light-emitting surface of the laser chip 3 or bypass it from the side of the laser chip 3. Therefore, the lead 31 does not enter the light-emitting path of the adjacent laser chip 3, eliminating the risk of light emission obstruction and laser ablation of the lead. At the same time, the lead 31 is short in length and arranged in an approximately straight line, avoiding the increase in resistance and additional power consumption caused by detours, which is beneficial to maintaining the electrical efficiency and thermal stability of the laser chip 3 under high current density.

[0053] Based on the above embodiments, under the condition that multiple laser chips 3 are arranged in a single row and are closely arranged, by means of the misalignment structure of the protrusion 211 and the notch 212 of the first conductive sheet 21 in the second direction y, the lead wire 31 is restricted to a short path outside the light emission area, thereby realizing unobstructed light emission and low resistance connection, and improving the optical quality and reliability of the laser module 100.

[0054] The arrangement structure of the lead wire 31 will be further explained below with reference to the specific locations of the protrusion 211 and notch 212 of the first conductive sheet 21.

[0055] like Figure 4 As shown, in the first specific embodiment, the protrusion 211 and the notch 212 are located on one side of the first conductive sheet 21 along the second direction y, and the lead wire 31 is located on one side of the laser chip 3 along the second direction y and extends along the second direction y, the second direction y being perpendicular to the first direction.

[0056] In this embodiment, each first conductive sheet 21 has a protrusion 211 extending on the same side in the second direction y and a recessed notch 212. Multiple first conductive sheets 21 are arranged sequentially along the first direction x, with the protrusion 211 of one first conductive sheet 21 embedded in the notch 212 of an adjacent first conductive sheet 21, maintaining an insulating gap between them in the second direction y. The output end of each laser chip 3 is directly soldered to the protrusion 211 of the corresponding first conductive sheet 21. Since the protrusion 211 and the notch 212 are concentrated on the same side, the pad areas of adjacent first conductive sheets 21 on that side are staggered and close together.

[0057] Each laser chip 3's input terminal is electrically connected to an adjacent first conductive sheet 21 via a lead 31. All leads 31 are located on the same side of the laser chip 3 along the second direction y (i.e., the same side as the protrusion 211 and the notch 212). Because the pad area of ​​the adjacent first conductive sheet 21 extends to the position immediately adjacent to the current laser chip 3 on this side through the staggered arrangement of the protrusion 211 and the notch 212, the lead 31 can directly bridge the connection along a path parallel to the second direction y. The lead 31 neither passes over the light-emitting surface of any laser chip 3, avoiding obstruction of the emitted laser and laser ablation of the lead, nor does it detour around the side of the laser chip 3, thus eliminating the increased resistance and power consumption caused by excessively long leads. Simultaneously, all leads 31 are concentrated on one side, facilitating packaging positioning, visual inspection, and subsequent insulation protection, resulting in better manufacturability.

[0058] like Figure 6 As shown, in the second specific embodiment, in the first direction x, one side of the first conductive sheet 21 has a protrusion 211 protruding along the first direction x, and the other side of the first conductive sheet 21 has a notch 212 recessed along the first direction x. The laser chip 3 is provided with leads 31 on both sides opposite to each other along the second direction y, and the leads 31 extend along the second direction y, which is perpendicular to the first direction x.

[0059] In this embodiment, each first conductive sheet 21 has a protrusion 211 extending along the first direction x on one side and a notch 212 recessed along the first direction x on the other side. Multiple first conductive sheets 21 are arranged sequentially at intervals along the first direction x, and the protrusion 211 of one first conductive sheet 21 is directly embedded into the notch 212 of an adjacent first conductive sheet 21 along the first direction x, forming a nesting in the first direction x. The output end of each laser chip 3 is welded and fixed to the protrusion 211 of the corresponding first conductive sheet 21.

[0060] Specifically, the input terminal of each laser chip 3 is electrically connected via two sets of leads 31. These two sets of leads 31 extend from opposite sides of the laser chip 3 along the second direction y, and after extending along the second direction y, are bonded to the pads (i.e., the notches 212 of the first conductive sheet 21 on both sides along the second direction y) of the adjacent first conductive sheet 21 on the corresponding sides. In this way, the leads 31 utilize the space in the second direction y to avoid the laser emission surface, achieving unobstructed connection; at the same time, the two sets of leads 31 share the current, resulting in lower equivalent resistance and less heat generation, which can significantly improve the reliability and lifespan of the laser module 100 under high current operating conditions. The dual-sided lead 31 structure takes into account strong current carrying capacity while maintaining a single-row, tightly arranged arrangement of the laser chips 3 without adding extra dimensions in the first direction x.

[0061] like Figure 3 and Figure 5As shown, in some embodiments, the electrical connector 2 further includes a second conductive sheet 22 and a third conductive sheet 23. The output end of the second conductive sheet 22 is electrically connected to the input end of the laser chip 3 at one end along the first direction x, and the input end of the third conductive sheet 23 is electrically connected to the output end of the laser chip 3 at the other end along the first direction x.

[0062] During operation, the positive terminal of the external power supply is electrically connected to the input terminal of the second conductive plate 22. Current flows from the output terminal of the second conductive plate 22 into the input terminal of the laser chip 3, driving the laser chip 3 to emit laser light. The light then flows from the output terminal of the laser chip 3 through the input terminal of the third conductive plate 23, and finally returns to the negative terminal of the external power supply from the output terminal of the third conductive plate 23. The heat generated by the laser chip 3 is vertically transferred to the first surface 1a of the substrate 1 via the electrical connector 2, and then conducted through the body of the substrate 1 to the second surface 1b for dissipation. The heat is transferred through a short vertical heat transfer path, resulting in low thermal resistance and improved heat dissipation efficiency.

[0063] In this embodiment, multiple laser chips 3 are arranged in a single, closely spaced column along a first direction x, with adjacent laser chips 3 interconnected serially via multiple first conductive plates 21. A second conductive plate 22 is located at the first end of this arrangement along the first direction x, with its output end close to the outermost first laser chip 3. The input end of the first laser chip 3 is electrically connected to the output end of the second conductive plate 22 via a lead 31, while its output end is soldered to the corresponding first conductive plate 21. Current thus enters the first laser chip 3 and flows sequentially through subsequent laser chips 3 and first conductive plates 21 until it reaches the last laser chip 3 located at the other end of the arrangement. The output end of the last laser chip 3 is directly soldered to the input end of a third conductive plate 23, which then collects the current and outputs it to an external power supply.

[0064] The specific structural layout of the electrical connector 2 described above will not cause the electrical connector 2 to bend or cross between the laser chips 3, resulting in simple wiring. Simultaneously, the second conductive sheet 22 and the third conductive sheet 23 can respectively form large-area pads with the first surface 1a of the substrate 1, maintaining current carrying capacity and further enhancing the heat dissipation effect of the substrate 1. Combined with the staggered arrangement of the protrusion 211 and notch 212 of the first conductive sheet 21, the second conductive sheet 22 and the third conductive sheet 23 can be correspondingly provided with protrusions or notches to maintain the shortest interconnection distance with the outermost laser chip 3 and to maintain the connection requirement that the lead 31 does not pass through any light-emitting surface, thereby maintaining the integrity and reliability of light emission from multiple laser chips 3.

[0065] To facilitate a detachable and reliable electrical connection between the laser module 100 and the external power supply. For example... Figure 1As shown, in some embodiments, the electrical connector 2 further includes a first terminal 24 and a second terminal 25. The first terminal 24 is electrically connected to the input end of the second conductive sheet 22, and the second terminal 25 is electrically connected to the output end of the third conductive sheet 23. Thus, both the first terminal 24 and the second terminal 25 are located outside the light-transmitting plate 4, avoiding obstruction of the light path.

[0066] To improve structural compactness, the input end of the second conductive sheet 22 and the output end of the third conductive sheet 23 are located on the same side of the first surface 1a. Thus, the first terminal 24 and the second terminal 25 are also located on the same side of the first surface 1a, which facilitates subsequent installation.

[0067] Furthermore, the first terminal 24 has a first threaded hole 24a, and the second terminal 25 has a second threaded hole 25a. The specifications of the first threaded hole 24a and the second threaded hole 25a can be selected according to the actual current rating and fastening strength requirements, for example, using standard threads such as M2 or M3. In actual use, the connector lug or connecting piece of the external power cable can be locked onto the first terminal 24 and the second terminal 25 respectively with screws. The positive pressure generated by the threaded engagement makes the contact surfaces fit tightly, thereby obtaining low contact resistance and good vibration resistance.

[0068] With the first terminal 24 and the second terminal 25 configured as described above, the laser module 100 can be integrated into the system without irreversible operations such as soldering or conductive adhesive curing. Electrical installation can be completed simply by tightening screws, significantly simplifying production assembly and on-site maintenance procedures. Simultaneously, the threaded connection can reliably withstand large drive currents, effectively preventing localized overheating or momentary interruptions due to poor contact, thus enhancing the long-term stability of the laser module 100. The first terminal 24 and the second terminal 25 can be made of copper alloy sheets integrally stamped with the second conductive sheet 22 and the third conductive sheet 23, with nickel or gold plating to maintain good electrical and thermal conductivity.

[0069] In existing technologies, laser chip packaging uses sealant or a light-transmitting plate for sealing. If a light-transmitting plate is used to seal the laser chip, holes need to be drilled in the light-transmitting plate to connect to an external power source. If sealant is used, it has poor weather resistance, is prone to aging and yellowing, and affects the light transmission effect.

[0070] To improve long-term airtightness and stability, avoid yellowing and aging caused by laser irradiation of the colloid, and eliminate the need for perforation in the light-transmitting plate, such as Figure 1 , Figure 2 and Figure 7As shown, the laser module 100 also includes a light-transmitting plate 4, which covers the side of the electrical connector 2 and the laser chip 3 facing away from the first surface 1a. The input end of the second conductive sheet 22 and the output end of the third conductive sheet 23 are located outside the light-transmitting plate 4 for electrical connection with an external power supply. Specifically, the light-transmitting plate 4 has a receiving groove 4a, which covers the side of the electrical connector 2 facing away from the substrate 1, and the laser chip 3 is housed in the receiving groove 4a. The input end of the second conductive sheet 22 and the output end of the third conductive sheet 23 are located outside the light-transmitting plate 4 for electrical connection with an external power supply. Specifically, the light-transmitting plate 4 is made of a material with high transmittance to the emission wavelength of the laser chip 3, such as optical glass. The contour and depth of the receiving groove 4a match the size of the laser chip 3 to accommodate it. The light-transmitting plate 4 provides protection for the laser chip 3 and forms a relatively sealed environment between the light-transmitting plate 4 and the electrical connector 2, serving to prevent dust, moisture, and impact on the laser chip 3.

[0071] Furthermore, the laser emitted by the laser chip 3 can be transmitted outward through the body of the light-transmitting plate 4, and the front side of the light-transmitting plate 4 (facing away from the surface of the laser chip 3) can serve as a light-emitting window. The input end of the second conductive sheet 22 and the output end of the third conductive sheet 23 both extend outward from the area covered by the receiving groove 4a and are finally exposed on the outside of the light-transmitting plate 4, facilitating electrical connection with an external power supply through wire bonding, plugging, or direct soldering.

[0072] When assembling the laser module 100, the electrical connector 2 with the second conductive sheet 22 and the third conductive sheet 23 can be fixed to the first surface 1a of the substrate 1 firstly; then, the laser chip 3 is mounted and soldered onto the second conductive sheet 22 and the third conductive sheet 23 to complete the conductive and thermal connection; next, the receiving groove 4a of the light-transmitting plate 4 is aligned with the laser chip 3 and covered onto the electrical connector 2, and fixed with sealant; finally, thermally conductive adhesive or a soldering layer is coated on the second surface 1b of the substrate 1 and coupled with the heat dissipation element or cooling element, thus completing the assembly of the laser module 100.

[0073] It should be noted that, since there is an electrical insulation gap between the second conductive sheet 22 and the third conductive sheet 23, in order to improve the sealing effect of the light-transmitting plate 4, the gap between the second conductive sheet 22 and the third conductive sheet 23 can be filled with sealant first. After the sealant has solidified, the light-transmitting plate 4 can be sealed and connected to the second conductive sheet 22 and the third conductive sheet 23. At this time, it is not necessary to make holes in the light-transmitting plate 4 to allow the second conductive sheet 22 and the third conductive sheet 23 to pass through.

[0074] In this embodiment, taking the first laser chip 3 along the first direction x as an example, its input terminal is electrically connected and fixed to the output terminal of the second conductive plate 22, and its output terminal is electrically connected and fixed to the first conductive plate 21; the input terminal of the second laser chip 3 is also electrically connected to the first conductive plate 21, and its output terminal is electrically connected to the second conductive plate 21; and so on, with the output terminal of the last laser chip 3 being electrically connected to the input terminal of the third conductive plate 23. Thus, each first conductive plate 21 serves as both the output connection point of the preceding laser chip 3 and the input connection point of the following laser chip 3, forming a series connection of all laser chips 3. The driving current flows in from the input terminal of the second conductive plate 22, is transmitted through each laser chip 3 and the intermediate first conductive plate 21, and finally returns to the external power supply from the output terminal of the third conductive plate 23.

[0075] The arrangement of the first conductive sheet 21 and the laser chip 3 allows multiple laser chips 3 to be mounted with extremely tight spacing. The welding areas of each first conductive sheet 21 and the electrodes of the laser chip 3 precisely correspond, resulting in short electrical connection paths and low impedance. The electrical connector 2 can be formed on the first surface 1a of the substrate 1 in a single metallization process, facilitating assembly. Simultaneously, heat from the back of each laser chip 3 is directly conducted downwards to the substrate 1 through the corresponding first conductive sheet 21, forming a short heat conduction path, which is beneficial for stable operation at high power densities.

[0076] like Figure 1 As shown, to further improve heat dissipation and temperature uniformity of the substrate 1, in some embodiments, the laser module 100 further includes a heat spreader 5 located on the second surface 1b of the substrate 1. Specifically, the heat spreader 5 can be fixed to the second surface 1b by means of large-area welding, thermally conductive adhesive bonding, or vacuum brazing, thereby reducing the contact thermal resistance at the interface between the two surfaces.

[0077] The heat generated by the laser chip 3 during operation is transferred to the first surface 1a of the substrate 1 via the electrical connector 2, and then conducted along the thickness direction of the substrate to the second surface 1b. After being spread and homogenized by the heat spreader 5, it is finally transferred to the heat dissipation element or cooling element. The heat spreader 5 can be made of a metal material with high thermal conductivity, such as copper, aluminum, or copper-molybdenum alloy, or it can be a heat spreader 5 with an internal capillary structure and phase change working fluid. The introduction of the heat spreader 5 can rapidly spread the concentrated heat on the second surface 1b along the planar direction, effectively eliminating local hot spots and reducing the temperature difference between multiple laser chips 3.

[0078] For a structure employing multiple laser chips 3 arranged in a single, closely spaced column along the first direction x, the output wavelength and optical power of the laser chips 3 are sensitive to temperature changes. Excessive temperature gradients between the laser chips 3 can lead to poor light output consistency. The heat spreader 5 rapidly expands the second surface 1b, reducing the temperature difference between the laser chips 3, maintaining the stability and wavelength uniformity of the output beam, and thus improving the long-term operational reliability and optoelectronic performance of the laser module 100.

[0079] In some embodiments, the substrate 1 is a ceramic substrate, and the second surface 1b of the substrate 1 has a copper-clad layer, to which the heat spreader 5 is soldered. Specifically, the substrate 1 is made of aluminum nitride or alumina ceramic. The copper-clad layer can be formed by direct copper plating or thick film printing and sintering, and its thickness and pattern can be customized according to heat dissipation requirements. The heat spreader 5 is a heat spreader made of copper or copper alloy, and is directly soldered onto the copper-clad layer through a solder layer. The soldering method can be reflow soldering or vacuum brazing. After soldering, a continuous and dense metal bonding interface is formed between the heat spreader 5 and the copper-clad layer, eliminating the contact thermal resistance caused by air gaps.

[0080] In addition, the copper cladding layer, as a transition layer between the substrate 1 and the heat spreader 5, solves the process problem of directly welding metal to the ceramic surface. On the other hand, it utilizes the high thermal conductivity of copper to uniformly and quickly transfer the heat from the substrate 1 to the heat spreader 5, and then the heat spreader 5 performs planar thermal expansion, which greatly improves the overall heat dissipation efficiency.

[0081] like Figure 1 As shown, in some embodiments, the laser module 100 further includes a temperature sensor 6, which is located on the first surface 1a. The temperature sensor 6 can be a temperature-sensing element such as a thermistor or a thermocouple, and is fixed near the laser chip 3 by surface mounting or adhesive bonding to monitor the temperature of the working area of ​​the laser chip 3 in real time.

[0082] The signal from temperature sensor 6 can be led out to an external control circuit via a separate lead or a conductive line integrated with electrical connector 2. Based on the real-time temperature data fed back by temperature sensor 6, the external control circuit dynamically adjusts the drive current or activates an over-temperature protection mechanism, thereby preventing wavelength drift, optical power attenuation, or even permanent damage to the laser chip 3 due to overheating. Directly integrating temperature sensor 6 onto the first surface 1a of substrate 1 allows for the acquisition of temperature information closest to the heat source, resulting in fast response and high temperature measurement accuracy, providing a data foundation for the automated control of laser module 100.

[0083] like Figure 7As shown, in some embodiments, an antireflection film is provided on the surface of the light-transmitting plate 4. The antireflection film is used to improve the transmittance of the laser and reduce interface reflection loss. The antireflection film can be deposited on at least one of the light-incident surface and the light-exit surface of the light-transmitting plate 4 by processes such as physical vapor deposition or ion-assisted deposition. The film material can be an oxide or fluoride multilayer optical thin film that matches the output wavelength of the laser chip 3.

[0084] After the antireflection coating is applied, the light energy loss caused by reflection when the laser emitted from the laser chip 3 passes through the light-transmitting plate 4 is significantly reduced, thereby effectively improving the overall photoelectric conversion efficiency and output optical power of the laser module 100. Simultaneously, the reduction in reflected light also helps suppress the reciprocating reflection of stray light within the receiving groove 4a, reducing optical feedback interference to the laser chip 3 and improving output stability. For applications requiring high output power, the introduction of the antireflection coating can achieve significant performance gains with almost no increase in size and weight.

[0085] An embodiment of the present invention provides a hair removal device, including a laser module 100. The laser energy emitted by the laser module 100 can effectively penetrate to the hair follicle root to achieve the hair removal effect. By reducing the overall structural volume of the laser module 100, the hair removal device using this laser module 100 can further compress the overall size of the device, improve convenience, and overcome the defect in the prior art where the structure is not compact enough due to the space occupied by the connection part of the electrode layer.

[0086] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A laser module (100), characterized in that, include: Substrate (1), said substrate (1) having a first surface (1a); Laser chips (3), wherein multiple laser chips (3) are disposed on the first surface (1a), and the multiple laser chips (3) are arranged at intervals along a first direction (x); and An electrical connector (2) is disposed between the laser chip (3) and the first surface (1a). The electrical connector (2) includes a plurality of first conductive sheets (21) arranged at intervals along the first direction (x), and each first conductive sheet (21) is electrically connected to a laser chip (3). The first conductive sheet (21) has a protrusion (211) and a notch (212). The laser chip (3) is located in the protrusion (211). The protrusion (211) of one first conductive sheet (21) is spaced in the notch (212) of an adjacent first conductive sheet (21).

2. The laser module (100) according to claim 1, characterized in that, If the distance between two adjacent laser chips (3) and the distance between two adjacent first conductive sheets (21) are both a, then 0.1mm≤a≤0.3mm is satisfied.

3. The laser module (100) according to claim 1, characterized in that, Each of the laser chips (3) is connected in series via the first conductive sheet (21).

4. The laser module (100) according to claim 3, characterized in that, The laser chip (3) has leads (31), the output end of the laser chip (3) is electrically connected to its corresponding first conductive sheet (21), and the input end of the laser chip (3) is electrically connected to another adjacent first conductive sheet (21) through leads (31).

5. The laser module (100) according to claim 4, characterized in that, The protrusion (211) and the notch (212) are located on one side of the first conductive sheet (21) along the second direction (y) and are arranged sequentially along the first direction (x). The lead (31) is located on one side of the laser chip (3) along the second direction (y) and extends along the second direction (y). The second direction (y) is perpendicular to the first direction (x).

6. The laser module (100) according to claim 4, characterized in that, In the first direction (x), one side of the first conductive sheet (21) is formed with a protrusion (211) that protrudes along the first direction (x), and the other side of the first conductive sheet (21) is formed with a notch (212) that is recessed along the first direction (x). The laser chip (3) is provided with leads (31) on both sides opposite to each other along the second direction (y), and the leads (31) extend along the second direction (y), which is perpendicular to the first direction (x).

7. The laser module (100) according to claim 1, characterized in that, The electrical connector (2) further includes a second conductive sheet (22) and a third conductive sheet (23). The output end of the second conductive sheet (22) is electrically connected to the input end of the laser chip (3) at the outermost end along the first direction (x), and the input end of the third conductive sheet (23) is electrically connected to the output end of the laser chip (3) at the outermost end along the other end along the first direction (x).

8. The laser module (100) according to claim 7, characterized in that, The electrical connector (2) further includes a first terminal (24) and a second terminal (25), wherein the first terminal (24) is electrically connected to the input end of the second conductive sheet (22), and the second terminal (25) is electrically connected to the output end of the third conductive sheet (23).

9. The laser module (100) according to claim 8, characterized in that, The first terminal (24) has a first threaded hole (24a), and the second terminal (25) has a second threaded hole (25a).

10. The laser module (100) according to claim 7, the laser module (100) further includes a light-transmitting plate (4), the light-transmitting plate (4) is disposed on the side of the electrical connector (2) and the laser chip (3) away from the first surface (1a), the input end of the second conductive sheet (22) and the output end of the third conductive sheet (23) are located outside the light-transmitting plate (4) for electrical connection with an external power supply.

11. The laser module (100) according to claim 10, wherein the light-transmitting plate (4) has a receiving groove (4a) on the side near the first surface (1a), and the laser chip (3) is housed in the receiving groove (4a).

12. The laser module (100) according to claim 10, wherein the light-transmitting plate (4) is integrally formed and its light-transmitting surface is covered with an anti-reflection film.

13. The laser module (100) according to claim 1, characterized in that, The laser module (100) further includes a heat spreader (5), and the substrate (1) also has a second surface (1b) disposed opposite to the first surface (1a), with the heat spreader (5) located on the second surface (1b) of the substrate (1).

14. The laser module (100) according to claim 13, characterized in that, The substrate (1) is a ceramic substrate, and the second surface (1b) of the substrate (1) has a copper cladding layer, and the heat spreader (5) is soldered to the copper cladding layer.

15. The laser module (100) according to claim 1, characterized in that, The laser module (100) also includes a temperature sensor (6), which is located on the first surface (1a).

16. A hair removal device, characterized in that, Includes the laser module (100) as described in any one of claims 1-15.

Images