An integrated light guide lens and a lamp having the same

Abstract

The application discloses an integrated light guide lens and a lamp with the same, wherein the light guide lens comprises an arc-shaped light emitting part and a plurality of columnar light guide parts below the light emitting part, and the light emitting part and the light guide parts are in an integrated structure; the light emitting part comprises a light emitting arc surface at the top and a light guide arc surface at the bottom, the plurality of light guide parts are arranged at equal angular intervals in the radial direction, and the light emitting end of the light guide part is smoothly connected with the light guide arc surface. In addition, the lamp with the light guide lens further comprises a plurality of first light sources arranged at equal angular intervals in the radial direction and in the same number as the light guide parts, and each first light source corresponds to each light guide part. The technical scheme can form light emitting areas with equal areas on the light emitting arc surface, effectively reduces the transmission loss of the outgoing light between the light guide part and the light emitting part, and effectively improves the light energy utilization efficiency.

Description

Technical Field

[0001] This utility model relates to the field of stage lighting technology, and more specifically, to an integrated light guide lens and a lighting fixture having the same. Background Technology

[0002] In existing technologies, stage lighting fixtures typically use multiple LED beads arranged in a single array to achieve diverse lighting effects. To improve uniformity, light guides or lenses are usually installed above the LED beads to achieve uniform light distribution. Existing light guides are usually individual cylindrical structures that can only handle the light from a single LED, resulting in discrete light spots on the light-emitting surface of the fixture. Light guide lenses, on the other hand, are usually circular structures that are only suitable for multiple LED beads arranged in a ring array, and form a ring-shaped light-emitting area on the light-emitting surface of the fixture.

[0003] The customer requested a light guide element capable of handling the emitted light from multiple radially arranged LED beads, and the light guide element should be able to form a continuous and uniform light-emitting area on the light-emitting end face. Our company has developed an integrated light guide lens and a luminaire incorporating it. Summary of the Invention

[0004] This invention provides an integrated light guide lens that can process the light emitted by multiple LED beads. When the light guide lens is installed inside the lamp, it can form a uniform and bright elongated light-emitting area on the light-emitting end face of the lamp. Moreover, the light-emitting part of the light guide lens is arc-shaped, which can make the lamp have a richer and more beautiful lamp structure.

[0005] On one hand, an integrated light guide lens includes an arc-shaped light-emitting part and a plurality of columnar light guide parts located below the light-emitting part, wherein the light-emitting part and the light guide parts are an integrated structure; the light-emitting part includes a top light-emitting arc surface and a bottom light-guiding arc surface, and the plurality of light guide parts are arranged at equal angular intervals along the radial direction, and the light-emitting end of the light guide part is smoothly connected to the light-guiding arc surface.

[0006] As a further improvement of this utility model, the light guide includes a light-emitting end with a preset divergence angle α and a light-incident end with a rectangular light-incident surface. The divergence angle α of the light-emitting ends of multiple light guides are all equal, and the local light-emitting arc surface of the light-emitting part corresponding to the light-emitting end of each light guide is all equal.

[0007] As a further improvement of this utility model, the height of the light guide portion decreases sequentially from both ends along the central axis of the light guide lens, and all the light incident surfaces are located on the same horizontal plane.

[0008] As a further improvement of this utility model, the radius R1 of the light-emitting arc surface is in the range of R1 > 20mm.

[0009] As a further improvement of this utility model, the arc length of the light-emitting end of the light guide is S2, the radius of the light guide arc surface is R2, and the angular distance between any two adjacent light guides is θ = S2 / 2 * R2.

[0010] As a further improvement of this utility model, the number of light guides is at least two, and most or all of the light guides are symmetrically distributed along the central axis of the light guide lens.

[0011] As a further improvement of this utility model, the light-emitting arc surface is a frosted arc surface with an arc-shaped array of protrusions.

[0012] On the other hand, a lighting fixture includes an integrated light guide lens as described in any of the above claims, and further includes a plurality of first light sources arranged radially at equal angular intervals, the same number as the number of light guide portions, with each first light source corresponding to each light guide portion.

[0013] As a further improvement of this utility model, the radial distance L1 between the light-incident surface and the first light source is in the range of 0.3mm≤L1≤0.7mm.

[0014] As a further improvement of this utility model, the light-incident area of ​​the light guide portion increases sequentially from both ends along the central axis of the light guide lens.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: (1) In this utility model, multiple light guides are arranged at equal angular intervals along the radial direction. The corresponding local light-emitting arc surface of each light guide is equal. The emitted light of each first light source is uniformly diffused to the light-emitting part through its corresponding light guide and forms a light-emitting area of ​​equal area on the light-emitting arc surface. The light guides in the prior art are mostly arranged at equal intervals. The light guides arranged at equal intervals cannot form a light-emitting area of ​​equal area on the arc-shaped light-emitting surface.

[0016] (2) In this utility model, the light emitting part and multiple light guiding parts are integrated into one structure. The emitted light first enters the light guiding part through the light input end, and then directly enters the light emitting part after being diffused by the light output end. This effectively reduces the transmission loss of the emitted light between the light guiding part and the light emitting part, thereby effectively improving the light energy utilization efficiency. In the prior art, the light guide column and lens are usually two separate light guiding units. There is a gap between the light guide column and the lens, which causes great loss of light during propagation. Attached Figure Description

[0017] Figure 1 This is a front view of the light guide lens of this embodiment.

[0018] Figure 2 This is a perspective view of the light guide lens of this utility model.

[0019] Figure 3 This is a front view of the light guide lens and the first light source of the present invention.

[0020] Figure 4 This is a perspective view of the light guide lens and the first light source installed in the lamp according to the present invention.

[0021] In the figure: 10-light guide lens; 1-light guide part; 11-light entrance end; 111-light entrance surface; 12-light exit end; 13-central axis; 2-light exit part; 21-light exit arc surface; 211-partial light exit arc surface; 212-protrusion; 22-light guide arc surface; 3-central axis; 20-first light source; 30-lamp fixture. Detailed Implementation

[0022] Combined with appendix Figure 1 and attached Figure 2 An integrated light guide lens includes an arc-shaped light-emitting part 2 and a plurality of columnar light guide parts 1 located below the light-emitting part 2. The light-emitting part 2 and the light guide parts 1 are an integrated structure. The light-emitting part 2 includes a top light-emitting arc surface 21 and a bottom light-guiding arc surface 22. The plurality of light guide parts 1 are arranged at equal angular intervals along the radial direction. The light-emitting end 12 of the light guide part 1 is smoothly connected to the light-guiding arc surface 22. The light-emitting section 2 has an arc-shaped structure, with the circumference of the light-emitting arc surface 21 coaxial with the circumference of the light-guiding arc surface 22. The extension of the central axis 13 of each light guide section 1 intersects at the center of the circumference of the light-emitting arc surface 21, and the angular distance between any two adjacent central axes 13 is equal. The light-emitting ends 12 of the multiple light guide sections 1 are located below the light-guiding arc surface 22 of the light-emitting section 2, and the width of the light guide section 1 is equal to the width of the light-emitting section 2. The side surfaces of the light guide section 1 are all total reflection surfaces, so the light in the light guide section 1 will not leak out from the side wall of the light guide section 1. Therefore, when light comes from different... When the light guide part 1 enters the light guide lens 10, the light rays in two adjacent light guide parts 1 will not interfere with each other; each light guide part 1 can correspond to a local light-emitting arc surface 211 on the light-emitting arc surface 21. The light rays entering from each light guide part 1 are uniformly scattered on the corresponding local light-emitting arc surface 211 after passing through the light-emitting part 2; that is, the light rays enter the light guide lens 10 from multiple light guide parts 1, enter the light-emitting part 2 from the light-emitting end 12 of the light guide part 1, and then exit through the local light-emitting arc surface 211 corresponding to the light guide part 1, forming multiple light-emitting areas of equal area at the light-emitting arc surface 21.

[0023] Traditional light guides and lenses are generally two independent parts, resulting in significant light loss during projection from the light guide to the lens. In this embodiment, the light guide lens 10 is an integrated structure, greatly reducing the light loss during propagation between the light guide section 1 and the light emitting section 2, effectively improving the utilization rate of light energy. Because the light emitting arc surface 21 of the light guide lens 10 adopts a special curved surface design, the light emission effect formed by the light emitting arc surface 21 exhibits a stronger sense of spatial layering. The beneficial effect of this embodiment is that each light guide section 1 corresponds to a different local light emitting arc surface 211 on the corresponding local light emitting arc surface 21, and the light emitted through each light guide section 1 can form a light-emitting area of ​​equal area on the corresponding local light emitting arc surface 211. The integrated structure of the light emitting section 2 and multiple light guide sections 1 helps to reduce the light loss caused by propagation between the light emitting section 2 and the light guide section 1.

[0024] As a new implementation method, combined with the appendix Figure 1 The light guide 1 includes a light-emitting end 12 with a preset divergence angle α and a light-incident end 11 with a rectangular light-incident surface 111. The divergence angles α of the light-emitting ends 12 of the multiple light guides 1 are all equal, and the local light-emitting arc surfaces 211 of the light-emitting part 2 corresponding to the light-emitting end 12 of each light guide 1 are all equal. The light-incident end 11 has a rectangular structure, with its lower surface forming a rectangular light-incident surface 111. The upper end of the light-incident end 11 connects to the light-exit end 12. The light-exit end 12 has a trapezoidal structure, wider at the top and narrower at the bottom, with its upper end connecting to the light-guiding arc surface 22. The widths of the light-guiding part 1 and the light-exiting part 2 are equal, and the arc length S1 of the corresponding local light-exiting arc surface 211 of each light-guiding part 1 is also equal, meaning that the light rays from multiple light-guiding parts 1 can be evenly distributed onto the light-exiting arc surface 21 of the light-exiting part 2. The edges of the corresponding local light-exiting arc surfaces 211 of every two adjacent light-guiding parts 1 are in close contact with each other, thus allowing light rays to pass through... When light is emitted from the local light-emitting arc surface 211 through the light guide section 1, a continuous and uninterrupted light-emitting area can be formed on the light-emitting arc surface 21, which can effectively avoid the appearance of dark areas between two adjacent local light-emitting arc surfaces 211; the sides of the light-emitting end 12 are all total reflection surfaces, which effectively prevents light from leaking out from the sides of the light-emitting end 12; there is an included angle between the total reflection surfaces on the left and right sides of the light-emitting end 12, which is the divergence angle α; the emitted light after being reflected by the total reflection surface on the light-emitting end 12 can enter the light-emitting section 2 with a larger divergence angle, and the emitted light can be more evenly distributed on the light-emitting arc surface 21. The beneficial effect of this embodiment is that the local light-emitting arc surfaces 211 corresponding to the light-emitting end 12 of each light guide 1 are all equal, and every two adjacent local light-emitting arc surfaces 211 are in close contact with each other; that is, the light-emitting area formed on the light-emitting arc surface 21 by the emitted light rays emitted from each light-emitting end 12 is equal, which is conducive to forming a continuous and uninterrupted light-emitting area on the light-emitting arc surface 21; the divergence angle α of the light-emitting end 12 is equal, which is conducive to the uniform distribution of emitted light rays in the light-emitting part 2.

[0025] As a new implementation method, combined with the appendix Figure 1 and attached Figure 2 The height of the light guide section 1 decreases sequentially from the central axis 3 of the light guide lens 10 towards both ends, and all the light incident surfaces 111 are located on the same horizontal plane. The light emitting section 2 is a three-dimensional arc shape with equal thickness, that is, the distance between the light emitting arc surface 21 and the light guide arc surface 22 is equal. If light enters the light emitting section with uneven thickness from the light guide section, the light will be scattered within the uneven thickness light emitting section and will be difficult to reach the corresponding local light emitting arc surface of the light guide section. Therefore, using a light emitting section 2 with uniform thickness allows the light to propagate along a predetermined path, and the light emission angle can cover the corresponding local light emitting arc surface 211. As those skilled in the art can understand, light sources are generally mounted on a flat light source substrate, that is, light sources mounted on the same light source substrate are all located on the same plane. If the multiple light incident surfaces 111 of the light guide lens 10 are not located on the same horizontal plane, it will be difficult to use the light emitting section 2 with uniform thickness. The adaptation of the light source and its substrate greatly increases the manufacturing cost and makes maintenance difficult; furthermore, there is a certain distance and angle between each light-incident surface 111 and each light source mounted on the same plane, making it difficult for all emitted light rays to enter the light guide lens 10, thus reducing the light collection efficiency of the light guide lens 10; in this embodiment, the light-incident surfaces 111 are all rectangular planes located on the same horizontal plane, which can better adapt to the light sources mounted on the same horizontal plane; in order to adapt to the light-emitting part 2 and multiple light-incident surfaces 111, the height of the light guide part 1 shows a changing trend; the light-emitting arc surface 21 is an outwardly convex arc, so the height of the light guide part 1 located in the middle of the light-emitting part 2 is the highest, and the height of the light guide part 1 shows a decreasing trend from the middle of the light-emitting part 2 towards both ends. The beneficial effect of this embodiment is that by adjusting the height of each light guide 1, each light incident surface 111 can be located on the same horizontal plane, which is conducive to the matching and installation of the light guide lens 10 and the light source; at the same time, the light guide 1 can also correspond to different local light emitting arc surfaces 211 on the light emitting arc surface 21, which is conducive to accurately guiding the emitted light to a specific local area 211 of the light emitting arc surface 21.

[0026] As a new implementation method, combined with the appendix Figure 1 and attached Figure 2The radius R1 of the light-emitting arc surface 21 is in the range of R1 > 20 mm. The light-emitting arc surface 21 is located on the circumference and is a segment of the arc on the circumference. The main purpose of the light guide lens 10 is to process the emitted light from multiple light sources, so that the emitted light is emitted from the light-emitting arc surface 21 and forms a uniform light emission effect. When R1 < 20 mm, the number of light guide parts 1 is less than two. At this time, the light guide lens 10 cannot process the emitted light from multiple light sources, and the design of the light guide lens is meaningless. When R1 > 20 mm, at least two light guide parts 1 can be distributed on the light guide arc surface 22. At this time, the light guide lens 10 can process the emitted light from at least two light sources. The beneficial effect of this embodiment is that the radius of the light-emitting arc surface 21 is related to the number of light guide parts 1. When R1 > 20 mm, the larger the radius of the light-emitting arc surface 21, the more light guide parts 1 are arranged on the light-emitting arc surface 22.

[0027] As a new implementation method, combined with the appendix Figure 1 The arc length S2 of the light-emitting end 12 of the light guide is R2, the radius of the light-guiding arc surface 22 is R2, and the angular distance between any two adjacent light guides 1 is θ = S2 / 2 * R2. There is a certain angular distance between each pair of adjacent light guides 1, which can effectively avoid the problem of uneven light emission effect on the light emission arc surface 211 caused by the overlap of local light emission arc surfaces 211; within a suitable angular distance range, a uniform transition light emission effect can also be formed on the light emission arc surface 21; in order to form a continuous transition light emission effect between the local light emission arc surfaces 211 corresponding to each light guide 1, and to form a continuous and uniform light emission effect on the light emission arc surface 21, the position of the local light emission arc surface 211 corresponding to the light guide 1 can be changed by adjusting the angular distance between each pair of adjacent light guides 1; when the angular distance θ between each pair of connected light guides 1 is greater than S2 / 2*R2, the local light emission arc surfaces 211 corresponding to each pair of adjacent light guides 1 are not adjacent, resulting in dark areas in the light emission effect formed on the light emission arc surface 21; when the angular distance θ between each pair of connected light guides 1 is less .... When R2, the corresponding local light-emitting arc surfaces 211 of every two adjacent light guide parts 1 overlap, resulting in uneven brightness in the light emission effect formed on the light-emitting arc surfaces 21; that is, the overlapping parts of the local light-emitting arc surfaces 211 are relatively bright, while the non-overlapping parts of the local light-emitting arc surfaces 211 are relatively dark. The beneficial effect of this embodiment is that when θ = S2 / 2 * R2, it can effectively prevent the appearance of dark or bright areas between the corresponding local light-emitting arc surfaces 211 of every two adjacent light guide parts 1.

[0028] As a new implementation method, combined with the appendix Figure 1The number of light guide parts 1 is at least two, and most or all of the light guide parts 1 are symmetrically distributed along the central axis 3 of the light guide lens 10. Taking ten light guide parts 1 as an example, each light guide part 1 is symmetrically distributed with the central axis 3 of the light guide lens as the axis of symmetry, and every two mutually symmetrical light guide parts 1 have the same shape; the ten light guide parts 1 are distributed radially at equal angular intervals below the light emitting part 2, and each light guide part 1 corresponds one-to-one with each partial light emitting arc surface 211 on the light emitting arc surface 21. Light entering from different light guide parts 1 can be gathered to the light emitting part 2 and emitted from the light emitting arc surface 21; in this embodiment, due to assembly reasons, the number of light guide parts 1 is nine; among them, eight light guide parts 1 are symmetrically distributed along the central axis 2; the other light guide part 1 and its adjacent light guide parts 1 are arranged at equal angular intervals, and there is no light guide part 1 symmetrical to it. The beneficial effect of this embodiment is that it can concentrate the emitted light from multiple light sources onto the light-emitting arc surface 21 for emission, and the light guide lens 10 transforms multiple individual light-emitting points into an overall light-emitting surface; the light guide parts 1 symmetrically distributed along the central axis 2 make the light guide lens 10 present a more aesthetically pleasing effect in the lamp.

[0029] As a new implementation method, combined with the appendix Figure 1 and attached Figure 2 The light-emitting arc surface 21 is a frosted arc surface with an array of arc-shaped protrusions 212. Multiple protrusions 212 are arranged in an array around the light-emitting arc surface 21, and the outer surface of each protrusion 212 is frosted. The beneficial effect of this embodiment is that the array of arc-shaped protrusions 212, through its uneven structure, can diffuse light more evenly, while the frosted surface further disperses the light. The two treatments work together to make the brightness distribution of the overall light-emitting arc surface 21 more balanced, which is conducive to forming a more uniform light-emitting effect.

[0030] Combined with appendix Figure 3 and attached Figure 4This utility model provides a lamp 30, including an integrated light guide lens 10 as described above, and also includes a plurality of first light sources 20 arranged radially at equal angular intervals. The light guide lens 10 is installed in the light output direction of the first light sources 20, and a plurality of light incident surfaces 111 correspond one-to-one with a plurality of first light sources 20. The number of first light sources 20 is equal to the number of light guides 1, and each light-incident surface 111 can completely cover each first light source 20. The light emitted by the first light source 20 enters the light guide 1 through its corresponding light-incident surface 111, and is emitted from the local light-emitting arc surface 211 corresponding to the light guide 1 after being dispersed through the light-emitting end 12 of the light guide 1. The light guides 1 are distributed radially at equal angular intervals below the light-emitting parts 2, and the multiple first light sources 20 are arranged radially at equal intervals. The light emitted by the multiple first light sources 20 enters the corresponding light guide 1 and is emitted from the corresponding local light-emitting arc surface 211 of the light guide 1. The light emitted by the multiple first light sources 20 can form a continuous and uniform light emission effect on the light-emitting arc surface 21.

[0031] As a new implementation method, combined with the appendix Figure 3 and attached Figure 4 The radial distance L1 between the light-incident surface 111 and the first light source 20 ranges from 0.3mm ≤ L1 ≤ 0.7mm. The light-emitting portion 2 of the light guide lens 10 has mounting posts at both ends for installation. The first light source 20 is mounted on the lamp plate, and the light guide lens 10 is mounted on the lamp plate via the mounting posts. When L1 < 0.3mm, the distance between the light guide portion 1 and the first light source 20 is too small, easily causing interference and affecting the installation of the light guide lens 10. However, at this time, the distance between the light-incident surface 111 and the first light source 20 is relatively close, so the light collection efficiency of the light guide portion 1 is high. When L1 > 0.7mm, the distance between the light guide portion 1 and the first light source 20 is too large. Although there is no interference between them, the distance between the light-incident surface 111 and the first light source 20 is relatively far, so the light collection efficiency of the light guide portion 1 is low. When 0.3mm ≤ L1 ≤ 0.7mm, the light collection efficiency of the light guide portion 1 is high, and there is no interference between the light guide portion 1 and the first light source 20. The beneficial effect of this embodiment is that when the value of L1 is in the range of 0.3mm≤L1≤0.7mm, it is beneficial to improve the light collection efficiency of each light guide part 1 and can effectively prevent interference between the light guide part 1 and the first light source 20.

[0032] As a new implementation method, combined with the appendix Figure 3 and attached Figure 4The light-incident area of ​​the light guide section 1 increases sequentially from the central axis 3 of the light guide lens 10 towards both ends. In this embodiment, to ensure that the light flux in each light guide section 1 is relatively uniform, the length of the light incident surface 111 gradually increases from the middle to both ends of the light guide lens 10. As those skilled in the art will understand, light propagates in a straight line, and the tilt angle of the light guide sections 1 located at both ends of the light guide lens 10 is the largest. Compared with the light loss of the light guide section 1 located in the middle of the light guide lens 10, the light loss of the light guide sections 1 located at both ends of the light guide lens 10 is greater. The central axis 13 of each light guide section 1 forms a certain angle with the horizontal plane. The closer the light guide section 1 is to the middle, the larger the angle, the smaller its tilt angle, and the lower the light loss rate. The closer the light guide section 1 is to both ends, the smaller the angle, the larger its tilt angle, and the higher the light loss rate. Therefore, the longer the light incident surface 111 is to the ends of the light guide lens 10, the larger its area, and the more light enters the light guide section 1, which is beneficial to making the light flux in each light guide section 1 more uniform. The beneficial effect of this embodiment is that increasing the light-incident area of ​​the light-incident surface 111 helps to ensure that the light flux in each light guide part 1 tends to be consistent, so that the brightness of the light emission effect formed on the local light-emitting arc surface 211 corresponding to each light guide part 1 is consistent.

[0033] The working principle of the technical solution of this utility model is explained as follows, as shown in the appendix. Figure 1 To be continued Figure 4 As shown, the light guide lens 10 is installed in the light-emitting direction of multiple first light sources 20, and each light guide part 1 corresponds to each first light source 20. When the first light source 20 emits light, the emitted light enters the corresponding light guide part 1 through the light-incident surface 111, and the light path is constrained inside the light guide part 1 by the total reflection surface. When it reaches the light-emitting end 12, the emitted light enters the light-emitting part 2 after being processed by the divergence angle α, and finally exits from the local light-emitting arc surface 211 corresponding to the light guide part 1. Each light guide part 1 independently guides the emitted light of different first light sources 20, so that they achieve uniform light mixing in the light-emitting part 2, and form a continuous and uniform light emission effect at the light-emitting arc surface 21.

Claims

1. An integrated light guide lens, characterized in that, It includes an arc-shaped light-emitting part and a plurality of columnar light-guiding parts located below the light-emitting part, wherein the light-emitting part and the light-guiding parts are an integral structure; the light-emitting part includes a top light-emitting arc surface and a bottom light-guiding arc surface, the plurality of light-guiding parts are arranged at equal angular intervals along the radial direction, and the light-emitting end of the light-guiding part is smoothly connected to the light-guiding arc surface.

2. The integrated light guide lens according to claim 1, characterized in that, The light guide includes a light-emitting end with a preset divergence angle α and a light-incident end with a rectangular light-incident surface. The divergence angle α of the light-emitting ends of multiple light guides is equal, and the local light-emitting arc surface of the light-emitting part corresponding to the light-emitting end of each light guide is equal.

3. The integrated light guide lens according to claim 2, characterized in that, The height of the light guide section decreases sequentially from both ends along the central axis of the light guide lens, and all light incident surfaces are located on the same horizontal plane.

4. The integrated light guide lens according to claim 1, characterized in that, The radius R1 of the light-emitting arc surface is in the range of R1 > 20 mm.

5. The integrated light guide lens according to claim 1, characterized in that, The arc length of the light-emitting end of the light guide is S2, the radius of the light-guiding arc surface is R2, and the angular distance between any two adjacent light guides is θ = S2 / 2 * R2.

6. The integrated light guide lens according to claim 1, characterized in that, The number of light guides is at least two, and most or all of the light guides are symmetrically distributed along the central axis of the light guide lens.

7. The integrated light guide lens according to claim 1, characterized in that, The light-emitting arc surface is a frosted arc surface with an array of arc-shaped protrusions.

8. A lamp, characterized in that, The light guide lens includes an integrated light guide lens as described in any one of claims 1 to 7, wherein the light guide portion of the light guide lens has a rectangular light incident surface; and further includes a plurality of first light sources arranged radially at equal angular intervals, the same number as the number of light guide portions, wherein each first light source corresponds one-to-one with each light guide portion.

9. A lamp according to claim 8, characterized in that, The radial distance L1 between the light-incident surface and the first light source is in the range of 0.3mm ≤ L1 ≤ 0.7mm.

10. A lamp according to claim 8, characterized in that, The light-incident area of ​​the light guide increases sequentially from both ends along the central axis of the light guide lens.

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