Light supplement module and coding reading device equipped with same

Abstract

The application relates to the technical field of code reading, and provides a light supplementing module and a code reading device provided with the same. The light supplementing module comprises an illumination structure and a lens structure. The illumination structure comprises a lamp plate and a plurality of lamp beads arranged on the lamp plate. The lamp plate is provided with a first light passing hole for a lens to acquire image information. The plurality of lamp beads are arranged at intervals along the circumference of the first light passing hole. The lens structure is arranged in layers with the lamp plate and is connected with the lamp plate. Along the radial direction of the first light passing hole, the lens structure is provided with a reflecting surface at a position close to the edge. The reflecting surface is arranged in a slope from inside to outside along the direction in which the lamp plate faces the lens structure. The light supplementing module provided by the application can contract the edge light to the middle part, so that the edge light can be fully utilized for illumination of the middle part, and the overall brightness of the light spot is improved.

Description

Technical Field

[0001] This application relates to the field of code reading technology, and in particular to a supplementary lighting module and a code reading device equipped with it. Background Technology

[0002] When reading codes, such as barcodes, insufficient ambient light can affect imaging quality and reading rate, and may even lead to reading failure. Therefore, supplementary lighting modules are usually required when reading codes.

[0003] In related technologies, most supplementary lighting modules employ a combination of multiple light sources and utilize diffusers and lenses to uniformly diffuse the light beams generated by these sources, allowing the light energy used for supplementary lighting to be concentrated as uniformly as possible into the designated field of view. However, due to the inherent limitations of refraction, edge rays cannot converge further towards the center, resulting in the light spot not shrinking further and still wasting light energy. Utility Model Content

[0004] Therefore, it is necessary to provide a supplementary lighting module that can further reduce and utilize edge light to improve the overall brightness of the light spot.

[0005] A supplementary lighting module includes an illumination structure and a lens structure. The illumination structure includes a lamp board and a plurality of LEDs disposed on the lamp board. The lamp board has a first light-transmitting hole for a lens to acquire image information, and the plurality of LEDs are arranged circumferentially at intervals along the first light-transmitting hole. The lens structure is stacked and connected to the lamp board. Along the radial direction of the first light-transmitting hole, the lens structure has a reflective surface near its edge, and the reflective surface is inclined from the inside to the outside along the direction of the lamp board toward the lens structure.

[0006] Understandably, multiple LEDs are arranged at intervals around the first light-transmitting aperture to ensure a uniform distribution of light energy along the aperture's circumference. The lens structure allows light to pass through and be refracted to the target location, illuminating the coding area. During this process, because the lens structure has reflective surfaces at its edges, and these surfaces are angled from the inside out along the direction from the lamp panel towards the lens structure, they reflect light emitted from the LEDs near the edges, causing the edge light to contract inwards, improving light utilization and thus increasing the brightness of the light spot.

[0007] In some embodiments, the reflective surface is arranged in a continuous ring around the outer periphery of the plurality of lamp beads; or, the lens structure has a plurality of reflective surfaces arranged circumferentially at intervals along the first light-transmitting hole, and the plurality of reflective surfaces correspond one-to-one with the plurality of lamp beads.

[0008] In some embodiments, the lens structure has a refractive surface located inside the reflective surface, and the refractive surface is a curved surface that curves from the inside out toward the lamp panel.

[0009] In some embodiments, the lens structure has an annular light-transmitting groove surrounding the outer periphery of the first light-transmitting hole. The light-transmitting groove is recessed from the side of the lens structure facing the lamp board toward the side away from the lamp board. The reflective surface and the refractive surface are respectively disposed on both sides of the light-transmitting groove along the radial direction of the first light-transmitting hole.

[0010] In some embodiments, along the axial direction of the first light-transmitting hole, the projection of each of the LED beads lies within the projection of the light-transmitting groove.

[0011] In some embodiments, the LED is located in the middle of the light-transmitting groove along the width of the groove.

[0012] In some embodiments, the lamp bead has a light source point, the light source point has a first distance h from the wall of the light-transmitting groove, the lens structure has a first sidewall facing the lamp panel, the first sidewall has a second distance d from the top of the lamp bead, and the light emission angle of the light source point is θ. The first distance, the second distance, and the light emission angle satisfy the following:

[0013] arctan(h / d) ≥ θ / 2.

[0014] In some embodiments, the refractive index of the lens structure is n;

[0015] The first incident angle of the light emitted by the lamp bead relative to the reflective surface is β, and the first incident angle and the refractive index satisfy: β > arcsin(1 / n); and / or, the second incident angle of the light emitted by the lamp bead relative to the refracting surface is α, and the second incident angle and the refractive index satisfy: α > arcsin(1 / n).

[0016] In some embodiments, the lens structure has a second light-transmitting hole in the middle, and the second light-transmitting hole is coaxially arranged with the first light-transmitting hole; and / or, the lens structure is snap-fitted into the lamp panel.

[0017] This application also provides a barcode reading device, including a barcode reading module and the aforementioned supplementary lighting module, wherein the supplementary lighting module is disposed on the object side of the barcode reading module. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology 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.

[0019] Figure 1 This is a first schematic diagram of a supplementary lighting module provided in an embodiment of this application;

[0020] Figure 2 This is a second schematic diagram of a supplementary lighting module provided in one embodiment of this application;

[0021] Figure 3 This is a third schematic diagram of a supplementary lighting module provided in an embodiment of this application;

[0022] Figure 4 Illuminance diagrams in related technologies;

[0023] Figure 5 Illuminance diagram of a supplementary lighting module provided in an embodiment of this application.

[0024] Reference numerals: 10, lighting structure; 11, lamp panel; 12, lamp bead; 20, lens structure; 21, reflecting surface; 22, refractive surface; 23, light-transmitting groove; 24, second light-transmitting hole; 25, snap-fit ​​arm; 26, first side wall; 231, outer groove wall; 232, inner groove wall; 251, snap-fit ​​protrusion; 1101, first light-transmitting hole. Detailed Implementation

[0025] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0026] It should be noted that when a component is referred to as being "fixed to" or "attached to" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0027] Furthermore, 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0028] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0029] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0030] In related technologies, supplementary lighting modules mostly employ a multi-source light source arrangement, utilizing diffuser plates and lenses to uniformly diffuse the light beams generated by the multiple sources, ensuring that the light used for supplementary lighting is converged as uniformly as possible to the designated field of view. During convergence, most of the light is dispersed to the designated area through lens refraction. This results in light rays closer to the edges tending to diverge outwards more easily, thus preventing these rays from being fully used to illuminate the central coding area and affecting the brightness of the center of the light spot. Specific illuminance diagrams in related technologies can be found by referring to... Figure 4 It is quite obvious that the light diffuses outwards from the four corners.

[0031] Based on this, one embodiment of this application provides a supplementary lighting module that can concentrate edge light rays towards the center, allowing them to be fully utilized for illumination of the central area and improving the overall brightness of the light spot. Please refer to [link to relevant documentation]. Figure 1 , Figure 2 , Figure 3 and Figure 5For example, the supplementary lighting module includes an illumination structure 10 and a lens structure 20. Specifically, the illumination structure 10 includes a lamp panel 11 and a plurality of LEDs 12 disposed on the lamp panel 11. The lamp panel 11 has a first light-transmitting hole 1101 for the lens to acquire image information, and the plurality of LEDs 12 are arranged at circumferential intervals along the first light-transmitting hole 1101. Meanwhile, the lens structure 20 is stacked and connected to the lamp panel 11. Along the radial direction of the first light-transmitting hole 1101, the lens structure 20 has a reflective surface 21 near its edge, and the reflective surface 21 is inclined from the inside to the outside along the direction of the lamp panel 11 toward the lens structure 20.

[0032] Because multiple LEDs 12 are arranged at intervals along the circumference of the first light-transmitting hole 1101, a ring-shaped light source distribution is formed around the outer periphery of the first light-transmitting hole 1101, ensuring a uniform distribution of light energy along the circumference of the first light-transmitting hole 1101 as much as possible. The first light-transmitting hole 1101 on the lamp board 11 provides an imaging channel for lens imaging, ensuring that image acquisition is not obstructed. The first light-transmitting hole 1101 is a circular hole, and multiple LEDs 12 are evenly distributed at intervals along the circumference of the first light-transmitting hole 1101. For example, six LEDs 12 can be provided and evenly distributed to improve illumination. Of course, three, four, or five LEDs 12 can also be provided, etc., this is only an example.

[0033] The lens structure 20 and the lamp plate 11 are stacked along the thickness direction of the lamp plate 11 and fastened with screws, or by snap-fit, or by a combination of both. This not only ensures reliable connection but also facilitates assembly and disassembly. In some specific embodiments, the edge of the lens structure 20 is provided with multiple snap-fit ​​arms 25 arranged at intervals along its circumference. Each snap-fit ​​arm 25 protrudes from the lens structure 20 toward the lamp plate 11 along the axial direction of the first light-transmitting hole 1101. Each snap-fit ​​arm 25 has a snap protrusion 251 protruding on one side radially inward along the first light-transmitting hole 1101. The lamp plate 11 can be snapped into the lens structure 20 through the snap protrusions 251 on the multiple snap-fit ​​arms 25. Each snap protrusion 251 has a bevel, which facilitates the assembly and disassembly of the lamp plate 11.

[0034] The lens structure 20 is used to refract the light emitted by the LED beads 12, ensuring that the light emitted by each LED bead 12 can converge to the central area and be evenly distributed. Since the lens structure 20 has a reflective surface 21 at its edge, and the reflective surface 21 is inclined from the inside to the outside along the direction of the lamp panel 11 towards the lens structure 20, light diverging towards the edge can be reflected towards the center, achieving light convergence, thereby improving light utilization and thus increasing the brightness of the light spot. Figure 5 As shown, the light spot formed by this supplementary lighting module has no outward diffusion at the edges and corners, and the light intensity in the central area is relatively high.

[0035] Among them, the reflective surface 21 can be a total reflection surface to more fully reflect this part of the light and further improve the light gathering effect.

[0036] Taking the lamp panel 11 located below the lens structure 20 as an example, the reflective surface 21 is inclined from bottom to top and from inside to outside. The light emitted by the lamp bead 12 near the edge shines onto the reflective surface 21 and is reflected towards the position near the center via the reflective surface 21. Here, "from inside to outside" as referred to in this application means from the inside to the outside along the radial direction of the first light-transmitting hole 1101.

[0037] Please see Figures 1 to 3 In some embodiments, the reflective surface 21 is arranged in a continuous ring around the outer periphery of the plurality of lamp beads 12. This arrangement increases the reflection range and ensures that light near the edge at any position is reflected to the central area, further improving the light energy utilization rate.

[0038] Alternatively, the lens structure 20 may have multiple reflective surfaces 21 arranged circumferentially along the first light-transmitting hole 1101, with each reflective surface 21 corresponding to a single LED chip 12. In other words, the lens structure 20 may have multiple reflective surfaces 21 arranged circumferentially along the first light-transmitting hole 1101 near its edge, with each reflective surface 21 corresponding to one LED chip 12, ensuring that light emitted by each LED chip 12 near its edge can be reflected by the corresponding reflective surface 21 to a position near the center area.

[0039] Please see Figures 1 to 3 In some embodiments, the lens structure 20 is provided with a refractive surface 22, which is located inside the reflective surface 21. The refractive surface 22 is a curved surface that curves from the inside out towards the lamp panel 11. That is, most of the light emitted by the lamp bead 12 can be refracted by the refractive surface 22 and focused towards the central area. Light near the edge can be reflected towards the central area by the reflective surface 21, thereby achieving overall light adjustment and improving the energy density at the center of the light spot.

[0040] In practical use, the lens structure 20 is provided with a second light-transmitting hole 24, which is coaxially arranged with the first light-transmitting hole 1101. Both the first light-transmitting hole 1101 and the second light-transmitting hole 24 are used by the lens to acquire coded images. The first light-transmitting hole 1101 can be a flat hole extending through the thickness direction of the lamp plate 11, and the side of the second light-transmitting hole 24 facing away from the first light-transmitting hole 1101 can be rounded, and the rounded corner can form the aforementioned refractive surface 22. The second light-transmitting hole 24 can be arranged in an arc shape along the thickness direction of the lens structure 20, with the arc extending radially outward along the second light-transmitting hole 24. Alternatively, the second light-transmitting hole 24 includes a straight section and an arc section connected to the straight section, with the arc section located at the end of the straight section facing away from the first light-transmitting hole 1101, and the arc section serving as the aforementioned refractive surface 22.

[0041] Please see Figures 1 to 3 In some embodiments, the lens structure 20 has an annular light-transmitting groove 23 surrounding the outer periphery of the first light-transmitting hole 1101. The light-transmitting groove 23 is recessed from the side of the lens structure 20 facing the lamp plate 11 towards the side away from the lamp plate 11. The reflective surface 21 and the refracting surface 22 are respectively disposed on both sides of the light-transmitting groove 23 along the radial direction of the first light-transmitting hole 1101. The light-transmitting groove 23 is provided to facilitate the collection of light emitted by the lamp bead 12. The light-transmitting groove 23 has an outer groove wall 231 and an inner groove wall 232. The inner groove wall 232 is connected to the outer groove wall 231 and is located on the inward side, that is, the side closer to the first light-transmitting hole 1101. Light near the edge can be refracted to the reflective surface 21 through the outer groove wall 231 and reflected towards the central area through the reflective surface 21; and light in the middle and inner side can be refracted to the refracting surface 22 through the inner groove wall 232 and focused towards the central area.

[0042] The outer groove wall 231 is arranged along the thickness direction of the lens structure 20 and parallel to the axis of the second light-transmitting hole 24. The inner groove wall 232 includes a first section and a second section connected to the first section, with the end of the second section facing away from the first section connected to the outer groove wall 231. The first section is arranged in an arc shape adapted to the refractive surface 22, and the second section can also be arranged in an arc shape accordingly. The thickness direction of the lens structure 20 is the same as the thickness direction of the lamp plate 11.

[0043] Please see Figure 1 and Figure 2 In some embodiments, along the axial direction of the first light-transmitting hole 1101, the projections of each LED bead 12 are within the projection of the light-transmitting groove 23. This arrangement facilitates ensuring that the light emitted by the LED bead 12 can be refracted as fully as possible through the groove wall of the light-transmitting groove 23 to the refractive surface 22 and the reflective surface 21, thereby improving the light energy utilization rate and making it more conducive to energy concentration and focusing.

[0044] Furthermore, the LED 12 is located in the middle of the light-transmitting groove 23 along its width. That is, by centering the LED 12 relative to the light-transmitting groove 23, the radial distance between the LED 12 and the outer groove wall 231 and inner groove wall 232 along the second light-transmitting hole 24 is ensured to be the same, facilitating uniform light distribution. When the inner groove wall 232 is arc-shaped, the side of the inner groove wall 232 facing the lamp plate 11 can be used as a measurement reference, ensuring that the distance between the LED 12 and this measurement reference is approximately equal to the distance between the LED 12 and the outer groove wall 231.

[0045] Specifically, the LED bead 12 has a light source point. The distance between the light source point and the outer groove wall 231 along the radial direction of the second light-transmitting hole 24 is approximately equal to the distance between the light source point and the inner groove wall 232 along the radial direction of the second light-transmitting hole 24. Therefore, the aforementioned two distances are collectively referred to as the first distance h between the light source point and the groove wall of the light-transmitting groove 23 along the radial direction of the first light-transmitting hole 1101. The lens structure 20 has a first sidewall 26 facing the lamp plate 11. The first sidewall and the LED bead 12 are axially spaced along the second light-transmitting hole 24, so that there is a second distance d between the top of the LED bead 12 and the first sidewall 26. At the same time, the light source point has a light emission angle. The first distance, the second distance, and the light emission angle satisfy: arctan(h / d) ≥ θ / 2.

[0046] In other words, in the right triangle corresponding to the first and second spacings, the first and second spacings satisfy the following trigonometric function relationship: tanθ=h / d, so the angle θ in this right triangle satisfies:

[0047] θ = arctan(h / d).

[0048] Therefore, the first and second spacings need to satisfy the above relationship to ensure that as much of the light emitted by the LED 12 as possible is received by the lens, thereby improving the light energy utilization rate.

[0049] Please see Figure 1 and Figure 2 In some embodiments, the refractive index of the lens structure 20 is n; the first incident angle of the light emitted by the lamp bead 12 relative to the reflecting surface 21 is β, and the first incident angle and the refractive index satisfy: β > arcsin(1 / n). That is, with arcsin(1 / n) as the critical angle c, the first incident angle needs to be greater than the critical angle. The critical angle refers to the angle of refraction that is exactly 90° when the light is incident at this critical angle, therefore sinc = 1 / n. In other words, this setting satisfies the total internal reflection requirement at the reflecting surface 21, making it easier to reflect as much light as possible.

[0050] The reflecting surface 21 can be an inclined plane or an inclined arc surface, but the arc surface gradually approaches the plane. It only needs to satisfy the requirement of reflecting light from the edge to the central region.

[0051] Furthermore, the second incident angle of the light emitted by the LED 12 relative to the refractive surface 22 is α, and the second incident angle and the refractive index satisfy: α > arcsin(1 / n). This setting ensures that the light can be refracted as much as possible, without being reflected into the interior of the lens structure 20, thereby further improving the light energy utilization rate.

[0052] Please see Figures 1 to 3This application also provides a barcode reading device, including a barcode reading module and the aforementioned supplementary lighting module, wherein the supplementary lighting module is disposed on the object side of the barcode reading module. The barcode reading module includes at least a lens and an image acquisition unit. The lens is mounted on the object side of the image acquisition unit. The supplementary lighting module can form a ring light source through multiple LEDs 12 to illuminate the target area to be read. In this process, the cooperation of the reflective surface 21 and the refractive surface 22 can be used to increase the brightness of the light spot at the center of the target area, thereby facilitating the image acquisition unit to acquire the encoded information through the lens.

[0053] Here, "object side" refers to the side facing the encoding.

[0054] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0055] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. A supplementary lighting module, characterized in that, include: The lighting structure (10) includes a lamp board (11) and a plurality of lamp beads (12) disposed on the lamp board (11). The lamp board (11) is provided with a first light-transmitting hole (1101) for the lens to acquire image information. The plurality of lamp beads (12) are arranged circumferentially at intervals along the first light-transmitting hole (1101). The lens structure (20) is stacked and connected with the lamp plate (11). Along the radial direction of the first light-transmitting hole (1101), the lens structure (20) is provided with a reflective surface (21) near the edge. The reflective surface (21) is inclined from the inside to the outside along the direction of the lamp plate (11) toward the lens structure (20).

2. The supplementary lighting module according to claim 1, characterized in that, The reflective surface (21) is arranged in a continuous ring around the outer periphery of the plurality of lamp beads (12); or, The lens structure (20) has a plurality of reflective surfaces (21) arranged circumferentially along the first light-transmitting hole (1101), and the plurality of reflective surfaces (21) correspond one-to-one with the plurality of lamp beads (12).

3. The supplementary lighting module according to claim 1, characterized in that, The lens structure (20) is provided with a refractive surface (22), which is located inside the reflective surface (21). The refractive surface (22) is a curved surface that curves from the inside out and toward the lamp plate (11).

4. The supplementary lighting module according to claim 3, characterized in that, The lens structure (20) is provided with an annular light-transmitting groove (23) surrounding the outer periphery of the first light-transmitting hole (1101). The light-transmitting groove (23) is recessed from the side of the lens structure (20) facing the lamp plate (11) toward the side away from the lamp plate (11). The reflective surface (21) and the refractive surface (22) are respectively disposed on both sides of the light-transmitting groove (23) along the radial direction of the first light-transmitting hole (1101).

5. The supplementary lighting module according to claim 4, characterized in that, Along the axial direction of the first light-transmitting hole (1101), the projection of each of the lamp beads (12) is within the projection of the light-transmitting groove (23).

6. The supplementary lighting module according to claim 5, characterized in that, The lamp bead (12) is located in the middle of the light-transmitting groove (23) along the width direction of the groove.

7. The supplementary lighting module according to claim 6, characterized in that, The lamp bead (12) has a light source point, and the light source point has a first distance h from the wall of the light-transmitting groove (23). The lens structure (20) has a first sidewall (26) facing the lamp plate (11), and the first sidewall (26) has a second distance d from the top of the lamp bead (12). The light emission angle of the light source point is θ. The first distance, the second distance, and the light emission angle satisfy: arctan(h / d) ≥ θ / 2.

8. The supplementary lighting module according to claim 3, characterized in that, The refractive index of the lens structure (20) is n; The first incident angle of the light emitted by the lamp bead (12) relative to the reflecting surface (21) is β, and the first incident angle and the refractive index satisfy: β > arcsin(1 / n); and / or, the second incident angle of the light emitted by the lamp bead (12) relative to the refractive surface (22) is α, and the second incident angle and the refractive index satisfy: α > arcsin(1 / n).

9. The supplementary lighting module according to any one of claims 1 to 8, characterized in that, The lens structure (20) has a second light-transmitting hole (24) in the middle, and the second light-transmitting hole (24) is coaxially arranged with the first light-transmitting hole (1101); and / or, The lens structure (20) is engaged with the lamp plate (11).

10. An encoding and reading device, characterized in that, It includes a code reading module and a supplementary light module as described in any one of claims 1 to 9, wherein the supplementary light module is disposed on the object side of the code reading module.

Images