A lighting device

Abstract

The application is suitable for the field of optical lighting technology, and provides a lighting device, which comprises a reflecting cylinder, a light source module and a lens. An inner circumferential surface of the reflecting cylinder is provided with a mounting groove. The light source module is arranged on an inner bottom wall of the reflecting cylinder. A side of the lens facing the inside of the reflecting cylinder is provided with a mounting boss in a ring shape. An inner circumferential surface of the mounting boss comprises a first light inlet surface, and an outer circumferential surface thereof comprises a first light outlet surface. In a direction along an optical axis of the lens and pointing to the outside of the lens, the first light outlet surface gradually moves away from the optical axis from one end close to the light source module to one end far away from the light source module. In an axial cross section passing through the optical axis, a first connecting line is arranged between an edge of the light source module and a radially inner edge of an inner bottom wall of the mounting groove. The first light outlet surface is configured to cause total reflection of light rays propagating along the first connecting line at the first light outlet surface. When wide-angle light rays enter the mounting boss and are incident on the first light outlet surface, the light rays cannot be emitted and cannot irradiate the inner circumferential surface of the reflecting cylinder, thereby avoiding overheating of the end of the reflecting cylinder.

Description

Technical Field

[0001] This application relates to the field of optical lighting technology, and in particular to a lighting device. Background Technology

[0002] In lighting devices, a tapered reflective light guide tube is typically used to reflect and initially mix light within its interior. The mixed light then passes through a lens located at the light outlet of the light guide tube for further adjustment of the light path. At the light outlet of the light guide tube, the lens is bonded to the inner circumference of the light guide tube using an organic adhesive, thereby achieving the functions of dustproofing, waterproofing, insect repellency, and enhanced light mixing.

[0003] Currently, lighting devices have several shortcomings: Firstly, the organic colloid used to bond lenses easily absorbs and scatters light energy, leading to rapid heat accumulation and overheating of the colloid itself. At the same time, the ultraviolet light from the light source will have a long-term photolytic effect on the colloid. Under these dual effects, the colloid is prone to aging, cracking, and detachment, directly damaging the cavity sealing structure and causing sealing failure. Secondly, the reflectivity of the metal light guide tube is low, and long-term exposure to light will accumulate a large amount of heat, which will not only accelerate the aging and failure of the surrounding colloid, but also cause local high temperature overheating problems in the lamp.

[0004] In summary, the aforementioned structural defects affect the device's enclosed protection system, leading to a decrease in the lamp's dust and water resistance, and severely reducing the lamp's operational stability and service life. Summary of the Invention

[0005] The purpose of this application is to provide an illumination device that offers a solution to improve the problem of heat at the edge of the light guide tube and the ease with which the lens and the end of the reflector tube can be sealed and fail.

[0006] This application provides a lighting device, including: A reflector cylinder, wherein the inner circumferential surface of the reflector cylinder is provided with a mounting groove that is recessed radially outward; The light source module is located inside the reflector and has a light-emitting area; The lens has an annular mounting boss on one side facing the inside of the reflector, and the mounting boss is located in the mounting groove. The inner peripheral surface of the mounting boss includes a first light-incident surface, and the outer peripheral surface of the mounting boss includes a first light-exit surface. The first light-emitting surface gradually moves away from the optical axis from the end closest to the light source module to the end furthest from the light source module; Within the axial section passing through the optical axis, there is a first line connecting the edge of the light-emitting area and the radial inner edge of the inner bottom wall of the mounting groove, which intersects the optical axis within the reflective cylinder. The first light-emitting surface is configured such that light rays propagating along the first line undergo total internal reflection at the first light-emitting surface.

[0007] In some embodiments, there is a gap between the first light-emitting surface and the inner peripheral surface of the mounting groove, and the gap is filled with a first medium; Within the axial section passing through the optical axis, the extension of the first connecting line and the first light-emitting surface have a first intersection point. The obtuse angle formed between the first connecting line and the tangent plane of the first light-emitting surface located at the first intersection point is γ, where γ ≥ 90° + β, and β = arcsin(n1 / n2), n1 is the refractive index of the first medium, and n2 is the refractive index of the lens; n1 < n2.

[0008] In some embodiments, the radial distance between the first incident surface and the optical axis gradually decreases in a direction along the optical axis of the lens and pointing outward from the lens; Within the axial section passing through the optical axis, the angle between the first connecting line and the first incident surface, with the opening facing outwards from the lens, is greater than or equal to 90°.

[0009] In some embodiments, the outer peripheral surface of the mounting boss further includes a limiting surface, which is connected to the side of the first light-emitting surface away from the lens along the optical axis; the angle between the limiting surface and the optical axis is smaller than the angle between the first light-emitting surface and the optical axis.

[0010] In some embodiments, the first intersection point is located on the side of the optical axis closer to the lens along the boundary line between the limiting surface and the first light-emitting surface.

[0011] In some embodiments, the inner circumferential surface of the mounting groove is provided with a limiting boss that protrudes radially inward, the inner circumferential surface of the limiting boss abuts against the limiting surface, and the gap is located on the side of the limiting boss along the optical axis near the lens.

[0012] In some embodiments, the reflector has an outer end face, and the first light-emitting surface is connected to the outer end face so that the gap is an annular closed space; The first medium is air.

[0013] In some embodiments, the inner bottom wall of the mounting groove is provided with a sealing groove recessed along the optical axis, and a sealing element is provided in the sealing groove; The mounting boss has an abutment surface that is connected to the first light-incident surface and located on the periphery of the first light-incident surface. The abutment surface abuts against the inner bottom wall of the mounting groove and is connected to the sealing element.

[0014] In some embodiments, the abutting surface is provided with a positioning boss protruding along the optical axis, the inner bottom wall of the mounting groove is provided with a positioning groove recessed along the optical axis, and the sealing groove is formed in the inner bottom wall of the positioning groove; the positioning boss is disposed in the positioning groove.

[0015] In some embodiments, the reflective tube includes a tube body and a reflective layer disposed on the inner circumferential surface of the tube body, and the mounting groove is disposed on the inner circumferential surface of the tube body along the optical axis direction, and the mounting groove is located on the side of the reflective layer closer to the lens; Within the axial section passing through the optical axis, the line connecting the radial edge of the light-emitting region and the edge of the reflective layer along the optical axis near the lens is designated as the third line, which coincides with the first line.

[0016] The lighting device provided in this application has the following advantages: The lighting device provided in this application embodiment has an annular mounting boss at the edge of the end face of the lens facing the inside of the reflector. The inner circumferential surface of the mounting boss includes a first light-incident surface, and the outer circumferential surface includes a first light-exiting surface. In the direction along the optical axis of the lens and pointing outward from the lens, the first light-exiting surface gradually moves away from the optical axis from the end near the light source module to the end away from the light source module. In the axial section passing through the optical axis, there is a first connecting line between the edge of the light source module and the radial inner edge of the inner bottom wall of the mounting groove, which intersects the optical axis inside the reflector. The first light-exiting surface is configured such that light rays propagating along the first connecting line undergo total internal reflection at the first light-exiting surface. When large-angle light rays from the light source module enter the mounting boss and are incident on the first light-exiting surface, they cannot be emitted due to total internal reflection and cannot illuminate the inner circumferential surface of the reflector, thus preventing the edge of the reflector from overheating and causing the seal between the lens and the reflector to fail. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an overall side view of the lighting device provided in the embodiments of this application; Figure 2 yes Figure 1 A cross-sectional view of the lighting fixture along line AA; Figure 3 This is an exploded axial view of the lighting device provided in the embodiments of this application; Figure 4 This is a cross-sectional structural diagram of the lens in the lighting device provided in the embodiments of this application; Figure 5 yes Figure 4 Enlarged view of point B in the middle; Figure 6 This is a cross-sectional structural diagram of the reflector and seal in the lighting device provided in the embodiments of this application; Figure 7 yes Figure 6 Enlarged view of point C in the middle; Figure 8 This is a schematic diagram of the optical path of the lighting device provided in the embodiments of this application; Figure 9 yes Figure 8 Enlarged view of point D in the middle; Figure 10 This is a schematic diagram of another sealing structure between the lens and the reflector in the lighting device provided in this application embodiment; Figure 11 yes Figure 10 A partial structural diagram of the middle lens; Figure 12 yes Figure 10 A partial structural diagram of the central reflector tube.

[0019] The markings in the diagram mean: 100-Lighting devices; 20-Reflective cylinder, 21-Cylinder body, 22-Reflective layer, 23-Reflective cavity, 231-Reflective surface, 24-Mounting groove, 240-First inner bottom wall, 241-First inner circumferential surface, 242-Limiting boss, 243-Gap, 25-Outer end face, 26-Sealing groove, 27-Positioning groove, 28-Light outlet; 30-Lens, 31-First light-incident surface, 32-First light-outceasing surface, 33-Second light-incident surface, 34-Second light-outceasing surface, 35-Mounting boss, 351-Abutting surface, 352-Limiting surface, 36-Positioning boss; 40 - Light source assembly, 41 - Light source module, 42 - Substrate; 50 - Seals; X-optical axis, S-radial plane, M-first medium; EF - First connection, EG - Second connection; H - First intersection point. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0021] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly or indirectly fixed to or set on that other component. When a component is referred to as "connected to" another component, it can be directly or indirectly connected to that other component. The terms "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the purpose of 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, and therefore should not be construed as a limitation of this patent. The terms "first" and "second" are used only for the purpose of description and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features. "A plurality" means two or more, unless otherwise explicitly specified.

[0022] In the description of this application, unless otherwise stated, " / " indicates that the objects before and after are in an "or" relationship. For example, A / B can mean A or B. "And / or" in this application is merely a description of the relationship between the related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be single or multiple. Furthermore, in the description of this application, "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single items or multiple items. For example, at least one of a, b, and c can be represented as: a, b, c, a+b, a+c, b+c, a+b+c, where a, b, and c can be single or multiple. As another example, at least one of a, b, or c can be represented as: a, b, c, a+b, a+c, b+c, a+b+c, where a, b, and c can be single or multiple.

[0023] To illustrate the technical solutions described in this application, the following detailed description is provided in conjunction with specific drawings and embodiments.

[0024] like Figure 1 , Figure 2 and Figure 3 As shown, this application embodiment provides a lighting device 100, which includes a reflector 20, a light source module 41, and a lens 30. As... Figure 2 and Figure 3 As shown, the reflector 20 is a device with a light outlet 28 on at least one side (e.g., Figure 6 and Figure 7 The cylindrical structure has an internal cavity that serves as a reflective cavity 23. For example... Figure 6 As shown, at least a portion of the inner circumferential surface of the reflecting cavity 23 is a reflecting surface 231. (As indicated...) Figure 2 As shown, the light source module 41 is disposed within the reflecting cavity 23, specifically at the bottom of the reflecting cavity 23, and is used to emit light towards the light exit port 28 of the reflecting cavity 23. The lens 30 is at least partially disposed within the reflecting cavity 23, specifically on the side of the light exit port 28 of the reflecting cavity 23. A certain distance can be maintained between the lens 30 and the light source module 41. Figure 8 As shown, part of the light from the light source module 41 is directly incident on the lens 30, and another part is reflected by the reflecting surface 231 before reaching the lens 30. Finally, the light rays exit from the lens 30.

[0025] like Figure 3 As shown, light source module 41 is a planar array light source. Figure 2 and Figure 3 As shown, lens 30 has an optical axis X, which also serves as the optical axis of the entire lighting device 100. Simultaneously, the light-emitting center line of the light source module 41 coincides with this optical axis X. Along the optical axis X, the direction from the light source module 41 to the lens 30 is from the inside out, and conversely, the direction from the lens 30 to the light source module 41 is from the outside in.

[0026] Furthermore, in this lighting device 100, the direction parallel to the optical axis X is the axial direction, the direction perpendicular to the optical axis X is the radial direction, and the direction surrounding the optical axis X is the circumferential direction.

[0027] like Figure 6 and Figure 7 As shown, the inner circumferential surface of the reflector cylinder 20 is provided with a radially outwardly recessed mounting groove 24. Optionally, the mounting groove 24 is located on the outer part of the inner circumferential surface of the reflector cylinder 20. Figure 6 and Figure 7 As shown, along the axial direction, the mounting groove 24 is located on the side of the reflective surface 231 facing away from the light source module 41. Figure 9 As shown, lens 30 is mounted in mounting groove 24 so that lens 30 is positioned relatively outward and has the largest possible axial distance from light source module 41. In this way, given the limited axial height of reflector 20, the reflective cavity 23 can provide the largest possible light mixing distance. Furthermore, along the axial direction, at least a portion of lens 30 is located within reflector 20, which helps improve the stability and reliability of the fixed connection between lens 30 and reflector 20.

[0028] The lens 30 is fixedly installed in the mounting groove 24. In some embodiments, the lens 30 is fixed to the inner bottom wall (axial bottom wall) and / or inner peripheral surface of the mounting groove 24 by means of optical adhesive.

[0029] like Figure 7As shown, the side of the reflector 20 with the light outlet 28 along its axial direction has an outer end face 25. On the outside of the lens 30, the surface of the lens 30 facing away from the light source module 41 can be lower than, higher than, or flush with the outer end face 25 of the reflector 20. For example... Figure 2 and Figure 9 As shown, in some embodiments of this application, the surface of the lens 30 is flush with the outer end face 25 of the reflector 20 on the outside of the lens 30.

[0030] like Figure 4 and Figure 5 As shown, the lens 30 has a ring-shaped mounting boss 35 on the edge of its end face facing the interior of the reflector cylinder 20. Figure 9 As shown, the mounting boss 35 is located within the mounting groove 24. Figure 5 As shown, the inner peripheral surface of the mounting boss 35 includes a first light-incident surface 31, and the outer peripheral surface of the mounting boss 35 includes a first light-exit surface 32. For example... Figure 5 As shown, on the side of the lens 30 facing the light source module 41, there is also a second light-incident surface 33, which is connected to the edge of the first light-incident surface 31. Figure 5 As shown, on the side of the lens 30 away from the light source module 41, there is also a second light-emitting surface 34, which is connected to the edge of the first light-emitting surface 32.

[0031] The second light-incident surface 33 can be either a plane or a curved surface. The second light-exit surface 34 can also be either a plane or a curved surface.

[0032] like Figure 5 As shown, in some embodiments of this application, the first light-emitting surface 32 is an outwardly expanding surface along the optical axis X of the lens 30 from the inside to the outside. That is, the first light-emitting surface 32 gradually moves radially away from the optical axis X from the end near the light source module 41 to the end away from the light source module 41. Figure 8 and Figure 9 As shown, within the axial section passing through the optical axis X, there is a first line EF connecting the radial edge of the light source module 41 (which refers to the edge of the light-emitting area of ​​the light source module 41, i.e., the outermost edge of the light-emitting device in the light source module 41) and the radial inner edge of the inner bottom wall of the mounting groove 24, which intersects the optical axis X in the reflection cavity 23. The first light-emitting surface 32 of the lens 30 is configured such that the light rays propagating along the first line EF undergo total internal reflection at the first light-emitting surface 32.

[0033] like Figure 8 As shown, the edge (radial edge) of the light source module 41 has point E, as... Figure 7As shown, the inner edge (radial inner edge) of the inner bottom wall of the mounting groove 24 has point F, which is also the axial edge of the reflective surface 231 away from the light source module 41. Furthermore, it can be understood that, circumferentially, the edge of the light source module 41 has multiple points E, which form a closed loop. The inner edge of the inner bottom wall of the mounting groove 24 has multiple points F, which form a closed loop. Radially, on the first line EF, points E and F are the two points furthest apart. That is, any point E and its radially opposite point F form a first line EF.

[0034] like Figure 8 As shown in the cross-sectional view, the light rays propagating along the first line EF represent the limiting angle of light rays from the light source module 41 that cannot be reflected by the reflecting surface 231. That is, the light rays propagating along the first line EF represent the smallest angle of light rays from the light source module 41 that cannot be reflected by the reflecting surface 231. Figure 9 As shown, let the plane perpendicular to the optical axis X be the radial plane S, then the angle between the first connecting line EF and the radial plane S is α.

[0035] In this embodiment, the first light-emitting surface 32 of the lens 30 is configured such that light rays propagating along the first connecting line EF undergo total internal reflection at the first light-emitting surface 32. Thus, light rays from the radial edge of the light source module 41 with an angle greater than or equal to α with the radial plane S can undergo total internal reflection at the first light-emitting surface 32 and cannot exit through it. It should be noted that light rays from the edge of the light source module 41 with an angle greater than α with the radial plane S may not even reach the first light-emitting surface 32, but instead enter the second light-emitting surface 34 before reaching it, and similarly will not be refracted through the first light-emitting surface 32. These light rays from the edge of the light source module 41 will not illuminate the inner circumferential surface of the reflector 20, and no photothermal conversion will occur at the inner circumferential surface of the reflector 20, avoiding overheating at the end of the reflector 20, thereby preventing adhesive failure between the mounting groove 24 and the lens 30.

[0036] Light rays from the non-edge of the light source module 41 either enter the reflecting surface 231 or, after entering the mounting boss 35, enter the first light-emitting surface 32 to satisfy the total internal reflection condition.

[0037] In some alternative embodiments, the generatrix of the first light-emitting surface 32 is a straight line segment inclined relative to the optical axis X, or the generatrix of the first light-emitting surface 32 is a curved segment protruding towards the optical axis X. Both of these ensure that light rays propagating along the first connecting line EF and other light rays from the light source module 41 undergo total internal reflection at the first light-emitting surface 32. In this embodiment, the example shown is a straight line inclined relative to the optical axis X. Within the axial section passing through the optical axis X, the first light-emitting surface 32 appears as a straight line segment.

[0038] like Figure 8 As shown, light rays from the edge of the light source module 41 with an angle less than α between it and the radial plane S can be incident on the reflecting surface 231 and reflected, and then emitted through the second light-incident surface 33 and the second light-outceasing surface 34.

[0039] The reflector 20 can be a cylindrical structure with an opening on one side, and the light source module 41 can be installed on the inner bottom wall of the reflector 20. For example... Figure 2 and Figure 3 As shown, in some embodiments of this application, the reflector 20 can be a cylindrical structure with openings on both sides, one side serving as the aforementioned light outlet 28, and the other side for the light source module 41 to be installed into the reflector cavity 23. For example... Figure 2 and Figure 3 As shown, the light source module 41 is mounted on the substrate 42, and the light source assembly 40 is composed of at least the light source module 41 and the substrate 42. The light source module 41 is installed in the opening on the other side of the reflector 20, and the substrate 42 is located on the side of the reflector 20 opposite to its light outlet 28, and blocks the opening on that side.

[0040] The inner circumferential surface of the reflecting cavity 23, or at least the reflecting surface 231, can be a central surface of revolution, obtained by rotating a generatrix around the optical axis X by 360°. Alternatively, the inner circumferential surface of the reflecting cavity 23, or at least the reflecting surface 231, can be composed of multiple surfaces connected circumferentially, for example, the multiple surfaces are distributed in a rotationally symmetrical manner. In other optional embodiments, the inner circumferential surface of the reflecting cavity 23, or at least the reflecting surface 231, can be set as two radially symmetrical surfaces, or surfaces of other shapes.

[0041] In some embodiments of this application, such as Figure 9 As shown, the first light-emitting surface 32 and the inner peripheral surface of the mounting groove 24 (e.g.) Figure 7 A gap 243 is provided between the first inner circumferential surfaces 241 shown, and the gap 243 is filled with a first medium M. For example... Figure 9As shown, the extension of the first connecting line EF and the first light-emitting surface 32 have a first intersection point H. The obtuse angle formed between the first connecting line EF and the tangent plane of the first light-emitting surface 32 located at the first intersection point H is γ. In other words, the first connecting line EF and the first light-emitting surface 32 form an obtuse angle γ on the side facing the outside of the lens 30, where γ≥90°+β, β=arcsin(n1 / n2), n1 is the refractive index of the first medium M, and n2 is the refractive index of the lens 30; n1<n2.

[0042] When light rays enter the first medium M from the lens 30 via the first light-emitting surface 32, the light travels from an optically denser medium to an optically less dense medium. At this time, the normal to the first light-emitting surface 32 and the first connecting line EF are... Figure 9 As shown by the dashed line perpendicular to the first emitting surface 32 (this normal is the normal to the tangent plane of the first emitting surface 32 at the first intersection point H), the angle between the light ray and the emitting surface 32 is greater than or equal to β, that is, greater than or equal to the critical angle for total internal reflection at the first emitting surface 32. In other words, when a ray propagating along the first line EF is incident on the first emitting surface 32, the angle of incidence is greater than or equal to β, satisfying the condition for total internal reflection. Therefore, the ray propagating along the first line EF can undergo total internal reflection. Other rays parallel to the first line EF also satisfy the condition for total internal reflection when incident on the first emitting surface 32.

[0043] like Figure 9 As shown, the light that undergoes total internal reflection is further emitted through the second light-emitting surface 34.

[0044] In other alternative embodiments, when the refractive index of the material of the reflector 20 is less than the refractive index of the material of the lens 30, the aforementioned gap 243 and the first medium M can be eliminated between the first light-emitting surface 32 and the inner circumferential surface of the mounting groove 24, and part of the inner circumferential surface of the reflector 20 can directly abut against the first light-emitting surface 32.

[0045] like Figure 4 , Figure 5 and Figure 9 As shown, along the optical axis X of lens 30 and from the inside out, the first light-incident surface 31 is a tapered surface. That is, along the optical axis X of lens 30 and from the inside out, the radial distance between the first light-incident surface 31 and the optical axis X gradually decreases. Since the first light-incident surface 31 gradually tilts radially inward along the optical axis X and from the inside out, the light rays incident on the first light-incident surface 31 can be deflected to a certain extent relative to the outside of lens 30. Therefore, the light rays are less likely to illuminate the inner bottom wall of the mounting groove 24 (e.g., Figure 7 The first inner bottom wall 240 and the inner circumferential surface of the mounting groove 24 are shown.

[0046] like Figure 4 and Figure 5As shown, in some embodiments, the mounting boss 35 of the lens 30 has an abutment surface 351 on the side axially close to the light source module 41, that is, the side close to the lens 30, which is connected to the first light-incident surface 31 and located on the periphery of the first light-incident surface 31. This abutment surface 351 is used to directly or indirectly abut against the inner bottom wall of the mounting groove 24.

[0047] like Figure 3 , Figure 7 and Figure 9 As shown, the lighting device 100 includes a sealing member 50, which is disposed between the inner bottom wall of the mounting groove 24 and the abutment surface 351 of the lens 30. The sealing member 50 is used to circumferentially seal the connection between the inner bottom wall of the mounting groove 24 and the abutment surface 351 of the lens 30, so as to isolate the reflective cavity 23 from the space outside the reflective cylinder 20.

[0048] In some embodiments, such as Figure 5 As shown, the outer peripheral surface of the lens 30 also includes a limiting surface 352, which is connected to the aforementioned abutment surface 351 and the first light-emitting surface 32. The limiting surface 352 is located on the axial side of the first light-emitting surface 32 closer to the lens 30. Radially, the limiting surface 352 is used to directly or indirectly abut against the inner peripheral surface of the mounting groove 24.

[0049] Optionally, the seal 50 may be disposed between the limiting surface 352 and the inner circumferential surface of the mounting groove 24.

[0050] In other embodiments, the lighting device 100 may include a plurality of seals 50, which are respectively disposed between the inner bottom wall of the mounting groove 24 and the contact surface 351 of the lens 30, and between the limiting surface 352 and the inner peripheral surface of the mounting groove 24.

[0051] In some alternative embodiments, the seal 50 is formed by curing a sealant material. Specifically, the sealant material is filled between the inner bottom wall of the mounting groove 24 and the abutment surface 351 of the lens 30 to bond the two together, and / or filled between the limiting surface 352 and the inner peripheral surface of the mounting groove 24 to bond the two together. After the sealant material cures, the seal 50 with a sealing function is formed.

[0052] By setting the first light-incident surface 31 in a tapered manner, it is possible to minimize the deflection of large-angle light rays into the sealing element 50 after they enter the first light-incident surface 31.

[0053] like Figure 6 and Figure 7As shown, the inner bottom wall of the mounting groove 24 is provided with a sealing groove 26 recessed along the X-axis. A portion of the contact surface 351 abuts against the inner bottom wall of the mounting groove 24, and the sealing groove 26 contains the aforementioned sealing element 50. The purpose of this arrangement is that, axially, the sealing groove 26 allows the sealing element 50 to be positioned closer to the light source module 41 and further away from the first light-incident surface 31. Therefore, it helps to avoid the path of light refracted from the first light-incident surface 31 into the lens 30. That is, even if the light refracted from the first light-incident surface 31 into the lens 30 is deflected towards the inner bottom wall of the mounting groove 24 and exits, it is less likely to irradiate the sealing element 50; thus, the amount of light irradiating the sealing element 50 is minimized.

[0054] like Figure 9 As shown, in some embodiments of this application, the angle between the first light-incident surface 31 and the optical axis X is θ, where θ is less than or equal to α. That is, on the side facing outwards from the lens 30, the angle ω between the first light-incident surface 31 and the first connecting line EF is greater than or equal to 90°. In other words, within the axial section passing through the optical axis X, the angle ω formed by the first connecting line EF and the first light-incident surface 31, with the opening facing outwards from the lens 30, is greater than or equal to 90°.

[0055] The purpose of this arrangement is to ensure that light rays from the edge of the light source module 41 and incident on the first light-incident surface 31 can enter the lens 30 perpendicularly or be deflected to the outside of the lens 30 after being refracted by the first light-incident surface 31.

[0056] like Figure 9 As shown, when θ equals α, ω = 90°. The light ray propagating along the first line EF can be incident perpendicularly to the first incident surface 31. After entering the mounting boss 35 of the lens 30, the light ray does not change its propagation direction until it reaches the first exiting surface 32. At this point, the light ray propagating along the first line EF also satisfies the total internal reflection condition at the first exiting surface 32, thus the light ray is further reflected to the second exiting surface 34. During this process, the light ray propagating along the first line EF will not irradiate the contact surface 351 of the lens 30, nor will it irradiate the limiting surface 352 of the lens 30.

[0057] like Figure 9 As shown, when θ is less than α, ω > 90°, the light ray propagating along the first line EF is not perpendicular to the first incident surface 31, but is refracted by the first incident surface 31 and enters the mounting boss 35. The refracted light ray will be relative to the normal of the first incident surface 31 (…). Figure 9 (As shown by the dashed line perpendicular to the first light-incident surface 31) it deflects towards the second light-outceasing surface 34, so that it will not illuminate the contact surface 351 of the lens 30, nor the limiting surface 352 of the lens 30.

[0058] like Figure 9As shown, the first incident surface 31 has another point G, and the line connecting point E on the edge of the light source module 41 and point G is the second line EG. The angle between the light ray propagating along the second line EG and the normal of the first incident surface 31 is φ, where φ > 0. The second line EG is located on the side of the normal of the first incident surface 31 closer to the first line EF. Therefore, the light ray propagating along the second line EG is refracted into the lens 30 at a small angle of incidence, and its refracted ray deflects outward relative to the normal of the first incident surface 31. Furthermore, when the refracted ray is incident on the first exiting surface 32, the angle of incidence on the first exiting surface 32 will be greater than the aforementioned critical angle for total internal reflection, and total internal reflection can also occur, without illuminating the contact surface 351 and the limiting surface 352.

[0059] Thus, in the embodiments of this application, the light incident on the reflecting surface 231, the light incident on the first light-incident surface 31, and the light incident on the second light-incident surface 33 cannot reach the inner bottom wall and inner peripheral surface of the mounting groove 24. This prevents the seal 50 from decomposing under the influence of light, thus avoiding sealing failure, and also prevents the end of the reflector 20 from overheating, thereby indirectly preventing the seal 50 from failing under the influence of heat. Overall, this ensures the stability of the seal 50 and the stability and reliability of the fixed connection between the lens 30 and the reflector 20.

[0060] In some embodiments of this application, such as Figure 10 and Figure 11 As shown, the contact surface 351 of the lens 30 is provided with a positioning boss 36 protruding along the optical axis X direction. The surface of the positioning boss 36 still serves as part of the contact surface 351. Figure 10 and Figure 12 As shown, the inner bottom wall of the mounting groove 24 is provided with a positioning groove 27 recessed along the X-axis, and the sealing groove 26 is formed on the inner bottom wall of the positioning groove 27. Figure 10 As shown, the positioning boss 36 is located in the positioning groove 27, and the sealing member 50 is connected to the side surface of the positioning boss 36 along the optical axis X near the light source module 41.

[0061] The purpose of this arrangement is to allow the seal 50 to be positioned further axially closer to the light source module 41 and further away from the lens 30, i.e., further away from the first light-incident surface 31. This further helps to reduce the possibility of the seal 50 being irradiated by stray light.

[0062] The sealing groove 26 and the positioning groove 27 are interconnected along the optical axis X. In the radial direction, the width of the sealing groove 26 can be equal to or less than the width of the positioning groove 27. That is, the sealing groove 26 can be formed by recessing into the entire inner bottom wall of the positioning groove 27, or it can be formed by recessing into a portion of the inner bottom wall of the positioning groove 27.

[0063] like Figure 5 As shown, in some embodiments of this application, the angle between the limiting surface 352 and the optical axis X is smaller than the angle between the first light-emitting surface 32 and the optical axis X. That is, the degree of deflection of the limiting surface 352 relative to the optical axis X is smaller. The limiting surface 352 is set closer to the optical axis X direction relative to the first light-emitting surface 32, or in other words, in the axial direction and from the outside to the inside, the limiting surface 352 does not extend in the same direction as the first light-emitting surface 32, but is set relatively radially outward. The purpose of this setting is to make the abutment surface 351 have a radial width as large as possible, thereby reserving sufficient radial space for the setting of the sealing groove 26 and the sealing member 50. This is beneficial to improving the reliability of the sealing between the lens 30 and the reflector 20 through the sealing member 50, as well as the reliability of the fixed connection.

[0064] In some embodiments, the generatrix of the limiting surface 352 is a straight line segment parallel to the optical axis X. That is, the limiting surface 352 is an annular surface extending along the optical axis X. This arrangement is also intended to facilitate the fabrication of the lens 30.

[0065] In some embodiments of this application, such as Figure 9 As shown, along the optical axis X, the first intersection point H is located on the side of the boundary line between the limiting surface 352 and the first light-emitting surface 32, closer to the lens 30. That is, the first intersection point H will not be located exactly at the edge of the first light-emitting surface 32 (i.e., the boundary line between the limiting surface 352 and the first light-emitting surface 32). Light rays propagating along the first connecting line EF will not be incident exactly at the edge of the first light-emitting surface 32 or the boundary line between the limiting surface 352 and the first light-emitting surface 32; instead, they can be completely located on the first light-emitting surface 32. Therefore, it can be ensured that light rays propagating along the first connecting line EF can undergo complete total internal reflection.

[0066] In some embodiments of this application, such as Figure 7 As shown, a limiting boss 242 protruding radially inward is provided on the inner circumferential surface of the mounting groove 24, and the inner circumferential surface of the limiting boss 242 abuts against the limiting surface 352 of the lens 30. Figure 9 As shown, the aforementioned gap 243 is located on the side of the limiting boss 242 along the optical axis X near the lens 30. The shape of the limiting boss 242 is adapted to the shape of the limiting surface 352.

[0067] The shape of the longitudinal section (axial section passing through the optical axis X) of the gap 243 is not limited, as long as the first light-emitting surface 32 and the inner circumferential surface of the mounting groove 24 are spaced apart and filled with a low-refractive-index first medium M. For example... Figure 9As shown, the longitudinal section of the gap 243 is triangular, with its two angles defined by the first light-emitting surface 32. Optionally, the longitudinal section of the gap 243 can be a right-angled triangle or an obtuse-angled triangle, a shape that facilitates the machining of the inner circumferential surface of the mounting groove 24. In other optional embodiments, the longitudinal section of the gap 243 can be rectangular, trapezoidal, or other shapes.

[0068] In some embodiments of this application, such as Figure 9 As shown, the first light-emitting surface 32 of the lens 30 is connected to the outer end face 25 of the reflector 20, so that the gap 243 is an annular closed space. The purpose of this arrangement is that, on the one hand, the first light-emitting surface 32 of the lens 30 can substantially abut against the inner circumferential surface of the mounting groove 24, and in the radial direction, the lens 30 can be held and fixed by the inner circumferential surface of the mounting groove 24; on the other hand, the annular closed space of the gap 243 is conducive to the filling of the first medium M, and also helps to prevent external impurities from entering the gap 243 and affecting the total internal reflection of the light at the first light-emitting surface 32, and also prevents external impurities such as water vapor from affecting the stability of the seal 50.

[0069] In some embodiments, the first medium M is air. In other embodiments, the first medium M may be a low-refractive-index material such as perfluorinated UV-curable resin, polytetrafluoroethylene, or fluorinated ethylene propylene copolymer.

[0070] In some embodiments of this application, such as Figure 6 As shown, the reflective tube 20 includes a tube body 21 and a reflective layer 22 disposed on the inner circumferential surface of the tube body 21. The reflective surface 231 is the inner circumferential surface of the reflective layer 22. In the axial direction, the edge of the reflective layer 22 near the lens 30 is lower than the outer end face 25 of the tube body 21. Thus, a mounting groove 24 is disposed on the inner circumferential surface of the tube body 21, and along the optical axis X direction, the mounting groove 24 is disposed on the side of the reflective layer 22 near the lens 30. In the radial direction, the thickness of the reflective layer 22 can be small. In some embodiments, the thickness of the reflective layer 22 is negligible compared to the thickness of the tube body 21.

[0071] In some embodiments, such as Figure 6 As shown, the radial inner edge of the mounting groove 24 can coincide with the edge of the reflective layer 22 along the optical axis X near the lens 30. In the axial section passing through the optical axis X, the line connecting the radial edge of the light-emitting area and the edge of the reflective layer 22 along the optical axis X near the lens 30 is defined as a third line, which coincides with the first line EF.

[0072] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A lighting device, characterized in that, include: The reflector tube (20) has an inner circumferential surface with a mounting groove (24) that is recessed outward in the radial direction; The light source module (41) is located inside the reflector tube (20) and has a light-emitting area; The lens (30) has an annular mounting boss (35) on one side facing the inside of the reflector (20), and the mounting boss (35) is located in the mounting groove (24). The inner peripheral surface of the mounting boss (35) includes a first light-incident surface (31), and the outer peripheral surface of the mounting boss (35) includes a first light-exit surface (32). The first light-emitting surface (32) gradually moves away from the optical axis (X) from the end closest to the light source module (41) to the end furthest from the light source module (41); Within the axial section passing through the optical axis (X), there is a first line (EF) between the radial edge of the light-emitting area and the radial inner edge of the inner bottom wall of the mounting groove (24) that intersects the optical axis (X) within the reflector (20). The first light-emitting surface (32) is configured such that light rays propagating along the first line (EF) undergo total internal reflection at the first light-emitting surface (32).

2. The lighting device as claimed in claim 1, characterized in that, There is a gap (243) between the first light-emitting surface (32) and the inner peripheral surface of the mounting groove (24), and the gap (243) is filled with a first medium (M); Within the axial section passing through the optical axis (X), the extension of the first connecting line (EF) and the first light-emitting surface (32) have a first intersection point (H). The obtuse angle formed between the first connecting line (EF) and the tangent plane of the first light-emitting surface (32) located at the first intersection point (H) is γ, γ≥90°+β, where β=arcsin(n1 / n2), n1 is the refractive index of the first medium (M), and n2 is the refractive index of the lens (30); n1<n2.

3. The lighting device as described in claim 2, characterized in that, In the direction along the optical axis (X) of the lens (30) and pointing outward from the lens (30), the radial distance between the first light-incident surface (31) and the optical axis (X) gradually decreases; Within the axial section passing through the optical axis (X), the angle formed by the first connecting line (EF) and the first incident surface (31) with the opening facing outward of the lens (30) is greater than or equal to 90°.

4. The lighting device as described in claim 2, characterized in that, The outer peripheral surface of the mounting boss (35) also includes a limiting surface (352), which is connected to the side of the first light-emitting surface (32) away from the lens (30) along the optical axis (X); the angle between the limiting surface (352) and the optical axis (X) is smaller than the angle between the first light-emitting surface (32) and the optical axis (X).

5. The lighting device as described in claim 4, characterized in that, The first intersection point (H) is located on the side of the optical axis (X) close to the lens (30) along the boundary line between the limiting surface (352) and the first light-emitting surface (32).

6. The lighting device as claimed in claim 4, characterized in that, The mounting groove (24) has a limiting boss (242) that protrudes radially inward on its inner circumferential surface. The inner circumferential surface of the limiting boss (242) abuts against the limiting surface (352). The gap (243) is located on the side of the limiting boss (242) along the optical axis (X) close to the lens (30).

7. The lighting device as claimed in claim 6, characterized in that, The reflector tube (20) has an outer end face (25), and the first light-emitting surface (32) is connected to the outer end face (25) so that the gap (243) is an annular closed space; The first medium (M) is air.

8. The lighting device as claimed in claim 1, characterized in that, The inner bottom wall of the mounting groove (24) is provided with a sealing groove (26) recessed along the optical axis (X) direction, and a sealing element (50) is provided in the sealing groove (26); The mounting boss (35) has an abutment surface (351) that is connected to the first light-incident surface (31) and located on the periphery of the first light-incident surface (31). The abutment surface (351) abuts against the inner bottom wall of the mounting groove (24) and is connected to the seal (50).

9. The lighting device as claimed in claim 8, characterized in that, The contact surface (351) is provided with a positioning boss (36) protruding along the optical axis (X) direction, the inner bottom wall of the mounting groove (24) is provided with a positioning groove (27) recessed along the optical axis (X) direction, and the sealing groove (26) is opened in the inner bottom wall of the positioning groove (27); the positioning boss (36) is located in the positioning groove (27).

10. The lighting device as claimed in any one of claims 1 to 9, characterized in that, The reflective tube (20) includes a tube body (21) and a reflective layer (22) disposed on the inner circumferential surface of the tube body (21). The mounting groove (24) is disposed on the inner circumferential surface of the tube body (21) along the optical axis (X) direction. The mounting groove (24) is located on the side of the reflective layer (22) closer to the lens (30). Within the axial section passing through the optical axis (X), the line connecting the radial edge of the light-emitting area and the edge of the reflective layer (22) along the optical axis (X) near the lens (30) is designated as the third line, which coincides with the first line (EF).

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