UV LED edge exposure lamp and multi-channel UV LED edge exposure assembly

Abstract

The invention relates to the field of UV edge exposure, in particular to a UV LED edge exposure lamp and a multi-channel UV LED edge exposure assembly. The UV LED edge exposure lamp comprises a UV LED lamp bead, a light guide element and a focusing lens; wherein the light guide element is in a prismatic table shape, the small end face of the light guide element is an incident face, the large end face of the light guide element is an emergent face, the incident face right faces the UV LED lamp beads, and the emergent face right faces the focusing lens; the light guide element is used for dodging light emitted by the UV LED lamp beads; the focusing lens is used for focusing the light emitted by the light guide element, and the focusing surface of the focusing lens is used as an exposure area. The UV LED edge exposure lamp disclosed by the invention has the advantages of high energy density, high uniformity, high parallelism, capability of realizing multiple channels through splicing, compact structure and high flexibility, and is suitable for edge exposure of areas with different sizes.

Description

Technical Field

[0001] The invention relates to the field of UV edge exposure, and in particular to a UV LED edge exposure lamp and a multi-channel UV LED edge exposure component. Background Art

[0002] In the LCD and other display panel industries, UV edge exposure lamps play a vital role. The essence of edge exposure lamps is a high-power exposure light source with a specified UV wavelength with high uniformity. Its purpose is to remove the photoresist at the edge of the substrate to prevent the edge photoresist from affecting the panel performance in subsequent processes, thereby helping to improve the yield and quality of LCD panels.

[0003] Traditional edge exposure lamps use high-pressure mercury lamps as exposure light sources, but with the continuous development of UV LED (ultraviolet light emitting diode) technology, edge exposure lamps with UV LED as light source have become increasingly popular because of their obvious advantages in exposure effects, spectral characteristics, production efficiency, process control and consistency, system integration and flexibility, life and maintenance, and environmental protection.

[0004] For example, in the Chinese patent with application number CN201620303103.X and patent name UV LED light source structure and parallel light exposure machine, the light source module involved uses a UV LED lamp bead array as the lighting light source. A free-form surface collimating lens is placed in front of each UV LED lamp bead on the array to generate a parallel light beam and solve the problem of large divergence angle of the UV LED light source. The light then passes through the compound eye lens homogenization system and the main reflector in turn to improve the uniformity and parallelism of the parallel light.

[0005] In the Chinese patent with application number CN201810458606.8 and patent name UV-LED optical system and exposure machine, the mercury lamp in the original exposure equipment is replaced with a UV-LED light source; after the UV-LED light source is collimated by an optical lens, the compound eye homogenization component achieves illumination uniformity. After the homogenized ultraviolet light is projected onto the curved mirror, it will irradiate the film at a nearly vertical angle.

[0006] Both of the above patents involve surface exposure light source technology with a specified UV wavelength with high uniformity, but there are still the following shortcomings:

[0007] Both patents are based on the optical path layout and optical elements of the original equipment to achieve the conversion and replacement of "mercury lamp" to "UV LED lamp beads". The implementation idea is roughly as follows: replace the original mercury lamp with "UV LED lamp bead array + collimating lens array" to obtain parallel light; then the parallel light is incident on the compound eye lens + main reflector (curved mirror) combination in the original optical path to achieve the two indicators of uniformity and parallelism. The core of the entire design lies in how to obtain parallel light from the UV LED end, and does not involve energy evaluation. And the optical path structure is neither compact nor has sufficient working distance. Therefore, these two patents are not suitable for the flexible scanning edge exposure application scenarios of edge exposure machines, especially for edge exposure applications in the large-format panel industry. Summary of the invention

[0008] The technical problem to be solved by the present invention is: in order to solve the deficiencies in the prior art, a UV LED edge exposure lamp is provided, which has high energy density, high uniformity, high parallelism, and can achieve multi-channel through splicing, has a compact structure, high flexibility, and is suitable for edge exposure of areas of different sizes.

[0009] In order to solve the above technical problems, the technical solution of the present invention is: a UV LED edge exposure lamp, comprising a UV LED lamp bead, a light guide element and a focusing lens; wherein,

[0010] The light guide element is in a prism shape, with a small end surface being an incident surface and a large end surface being an exit surface, the incident surface facing the UV LED lamp bead, and the exit surface facing the focusing lens;

[0011] The light guide element is used to homogenize the light emitted by the UV LED lamp bead; the focusing lens is used to focus the light emitted by the light guide element, and the focusing surface of the focusing lens is used as the exposure area.

[0012] In order to further match the square exposure surface and take into account the compactness of multiple UV LED edge exposure lamps after splicing, the light guide element is in the shape of a quadrangular pyramid, and the light-transmitting surface of the focusing lens is rectangular.

[0013] In order to better match the light guide element, the light emitting surface of the UV LED lamp bead is rectangular.

[0014] In order to further compress the divergence angle of the light source, allow the energy to enter the subsequent optical elements as much as possible, and ensure the uniform light performance of the light guide element at a reasonable length, the exit surface of the light guide element is proportionally enlarged relative to the incident surface, and the side length magnification factor is ≥3.

[0015] Furthermore, in order to allow as much energy radiated by the UV LED lamp beads as possible to enter the light guide element, the incident surface of the light guide element is a concave surface.

[0016] In order to further avoid the energy loss of the UV LED lamp bead radiation as much as possible, the incident surface of the light guide element is in close contact with the UV LED lamp bead and completely covers the light emitting surface of the UV LED lamp bead.

[0017] In order to further improve energy utilization and avoid excessive energy reflection to the UV LED lamp beads, the incident surface and the exit surface are respectively coated with UV anti-reflection films.

[0018] Furthermore, the focusing lens is coated with a UV anti-reflection film layer.

[0019] In order to further reduce costs while ensuring performance, the focusing lens is a plano-convex lens.

[0020] In order to solve the problem of large-area exposure, the present invention also relates to a multi-channel UV LED edge exposure assembly, comprising a plurality of UV LED edge exposure lamps, and focusing lenses of the plurality of UV LED edge exposure lamps are spliced ​​with each other.

[0021] After adopting the above technical solution, a prism-shaped light guide element is set behind each UV LED lamp bead to improve the uniformity of radiation and exposure. Then, a focusing lens is set behind each light guide element to achieve exposure at a specified working distance. The focusing surface of each focusing lens contributes to the exposure of a small area at the corresponding position. If large-area exposure is required, it is only necessary to splice multiple UVLED edge exposure lamps into multiple channels to achieve edge exposure of areas of different sizes, meeting technical requirements such as uniformity, radiation power density, and working distance. The length of the spliced ​​structure mainly depends on the length of the light guide element, and the width and height mainly depend on the size of the focusing lens array, and the overall space is compact. Moreover, because of the compact structure and high flexibility of use, in addition to being convenient for coordinating the mechanism to realize the scanning function, it is also convenient to replace light source modules of different wavelengths. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic structural diagram of the UV LED edge exposure lamp of the present invention;

[0023] Figure 2 is a schematic structural diagram of a light guide element of the present invention;

[0024] Figure 3 It is a schematic structural diagram of a multi-channel UV LED edge exposure assembly of the present invention;

[0025] Figure 4 is a radiation power density diagram of a multi-channel UV LED edge exposure assembly in a 5x5 array in an embodiment of the present invention;

[0026] In the figure, 1, UV LED lamp beads; 2, light guide element; 21, incident surface; 22, exit surface; 3, focusing lens;

[0027] Figure 4 (a) is the light radiation illumination diagram;

[0028] Figure 4 (b) is the contour curve of light radiation illumination. DETAILED DESCRIPTION

[0029] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention, and directions and references (e.g., up, down, left, right, etc.) may only be used to help describe the features in the drawings. Therefore, the following specific embodiments are not to be taken in a limiting sense, and the scope of the subject matter claimed is limited only by the attached claims and their equivalents.

[0030] like Figure 1 and Figure 2 As shown, a UV LED edge exposure lamp includes a UV LED lamp bead 1, a light guide element 2 and a focusing lens 3; wherein,

[0031] The light guide element 2 is in a prism shape, with a small end surface being an incident surface 21 and a large end surface being an exit surface 22. The incident surface 21 faces the UVLED lamp bead 1, and the exit surface 22 faces the focusing lens 3.

[0032] The light guide element 2 is used to homogenize the light emitted by the UV LED lamp bead 1; the focusing lens 3 is used to focus the light emitted by the light guide element 2, with the focusing surface of the focusing lens 3 serving as the exposure area.

[0033] Specifically, a prism-shaped light guide element 2 is set behind each UV LED lamp bead 1 to improve the uniformity of radiation and exposure, and then a focusing lens 3 is set behind each light guide element 2 to achieve exposure at a specified working distance. The focusing surface of each focusing lens 3 contributes to the exposure of a small area at the corresponding position. If large-area exposure is required, it is only necessary to splice multiple UV LED edge exposure lamps into multiple channels to achieve edge exposure of areas of different sizes, meeting technical requirements such as uniformity, radiation power density, and working distance. The length of the spliced ​​structure mainly depends on the length of the light guide element 2, and the width and height mainly depend on the size of the focusing lens 3 array, and the overall space is compact. In addition, because of the compact structure and high flexibility of use, it is not only convenient to cooperate with the mechanism to realize the scanning function, but also convenient to replace light source modules of different wavelengths.

[0034] In this embodiment, the material of the light guide element 2 can be quartz glass, and the incident surface 21 matches the light emitting surface of the UV LED lamp bead 1, that is, the incident surface 21 just covers the light emitting surface of the UV LED lamp bead 1, and the center lines of the two are aligned. The incident surface 21 of the light guide element 2 can be a plane or a concave surface, preferably a concave surface, so that the energy radiated by the UV LED lamp bead can enter the light guide element 2 as much as possible.

[0035] In this embodiment, based on the characteristics of the prism structure, the exit surface 22 of the light-guiding element 2 is proportionally enlarged relative to the incident surface 21. The side length magnification factor is preferably greater than or equal to 3, which can not only compress the divergence angle of the light source so that the energy can enter the subsequent optical elements as much as possible; but also ensure the uniform light performance of the light-guiding element 2 at a reasonable length (there is a concept of "optical expansion" in the optical system, and the optical expansion is a constant quantity, which refers to the product of the area through which the light beam passes and the solid angle of the light beam at this area. This spatial concept can be transferred to the plane to understand that: when the light travels from the incident surface 21 of the light-guiding element 2 to the exit surface 22, because the side length of the exit surface 22 is proportionally enlarged by N times, the light angle of the exit surface 22 in this direction is compressed by N times. In order to allow more light to enter the focusing lens 3, it is necessary to compress the angle The smaller the better, but this means that the exit surface 22 needs to be magnified more times, which will make the size of the subsequent optical element (focusing lens 3) larger, sacrificing the system volume. Therefore, from the comprehensive compromise of angle compression, system volume, and lighting performance, it is more appropriate to have a side length magnification of at least 3 times, and 3 times is the most preferred. In addition, the light-guiding element 2 can achieve uniform light, which requires the incident light to be fully reflected multiple times in the light-guiding element 2 to form a virtual multi-light source array. When the ratio of the incident surface 21 and the exit surface 22 is too different, in order to satisfy the multiple total reflections, the length of the light-guiding element will be too long, thereby increasing the length of the entire exposure system, again sacrificing the system volume. ).

[0036] It should be noted that when the incident surface of the light-guiding element 21 is a concave surface, the exit surface 22 of the light-guiding element 21 is still a plane. In this case, since the concave surface of the incident surface 21 is processed based on the rectangular plane, the concave surface contour is the inscribed circle of the rectangular plane. Therefore, proportional enlargement refers to the relationship between the concave circumscribed rectangle and the exit surface 22.

[0037] In this embodiment, the focal length of the focusing lens 3 is determined by the working distance, and its focal length can be adjusted according to the focus position. The focal length and other parameters of the focusing lens 3 can be flexibly modified according to different working distances without affecting other parameters such as uniformity. The material of the focusing lens 3 can also be quartz glass. Considering the cost, performance and other factors, a plano-convex lens is generally used.

[0038] It should be noted that in order to make the energy emitted by the light guide element 2 enter the focusing lens 3 as much as possible and improve the energy utilization rate, the distance between the light guide element 2 and the focusing lens 3 should not be too far. The distance depends on the size of the light passing surface of the two and the light angle of the light guide element 2 exit surface 22.

[0039] In one embodiment, Figure 2 As shown, the light guide element 2 is in the shape of a quadrangular pyramid, and the light passing surface of the focusing lens 3 is rectangular. In this way, the need for a square exposure surface can be met. If large-area exposure is required, it is only necessary to arrange multiple UV LED edge exposure lamps in an array, and multiple focusing lenses 3 can be spliced ​​to achieve space compactness.

[0040] It should be noted that the light-transmitting surface of the focusing lens 3 can be of various shapes, but for the rectangular exposure surface requirement, the rectangular light-transmitting surface is the optimal solution. Here, the light-guiding element adopts a four-sided pyramid structure because the exposure surface is rectangular; and the rectangular light-transmitting surface of the focusing lens 3 is to a certain extent to adapt to the rectangular exit surface 22 of the light-guiding element 2. There is no restriction on the shape of the exit surface 22 and the shape of the light-transmitting surface of the focusing lens 3 under normal circumstances, as long as the light-transmitting surface of the focusing lens 3 is larger than the exit surface 22. The purpose is to allow as much light from the exit surface 22 carrying the luminous angle as possible to enter the focusing lens 3 to achieve the power density requirement. In this embodiment, the light-transmitting surface of the focusing lens 3 and the exit surface 22 have the same shape, which is also determined by comprehensive considerations such as volume, processing factors, and cost.

[0041] In addition, the light-emitting surface of the UV LED lamp bead 1 may be a sphere with a lamp bead, or it may be a plane, which is not limited here. As long as the light-guiding element 2 can cover the light-emitting surface of the UV LED lamp bead 1 at a close distance, the shape of its incident surface 21 and the exit surface 22 can be used to shape the lamp bead. In this embodiment, because the exit surface 22 of the light-guiding element 2 is a rectangle, the UV LED lamp bead 1 can eventually become a rectangle.

[0042] In one embodiment, the incident surface 21 and the exit surface 22 are respectively coated with UV anti-reflection films. In this way, the energy utilization rate is improved, and the incident surface 21 of the light guide element 2 is reduced due to excessive energy reflected to the UV LED lamp bead 1, which causes energy burden on the UV LED lamp bead 1 and affects the heat dissipation of the UV LED lamp bead 1; at the same time, the system stray light can be reduced.

[0043] In one embodiment, the focusing lens 3 is coated with a UV anti-reflection film layer, so that the energy utilization rate can be improved.

[0044] like Figure 3 As shown, a multi-channel UV LED edge exposure assembly includes a plurality of UVLED edge exposure lamps as in any of the above embodiments, and the focusing lenses 3 of the plurality of UV LED edge exposure lamps are spliced ​​with each other.

[0045] Specifically, each UV LED edge exposure lamp contributes to the exposure of a small area at a corresponding position on the focusing surface of its focusing lens 3, and a multi-channel UV LED edge exposure assembly formed by splicing multiple UV LED edge exposure lamps realizes large-area exposure. The length of the entire multi-channel UV LED edge exposure assembly mainly depends on the length of the light guide element 2, and the width and height mainly depend on the size of the plane formed by splicing the focusing lenses 3 of multiple UV LED edge exposure lamps.

[0046] In addition, multiple UV LED edge exposure lamps can be flexibly arranged according to the different needs of the required lighting shapes. In order to achieve square area lighting, an NxN channel layout is adopted. If an Nx1 channel layout is adopted, linear area lighting can be achieved. Similarly, lighting of other specific areas can also be achieved.

[0047] In addition, this multi-channel design has a high degree of multiplexing of optical components, which can effectively reduce costs.

[0048] In this embodiment, a plurality of UV LED lamp beads 1 can form a lamp bead array, and the entire multi-channel UV LED edge exposure assembly uses the lamp bead array as a radiation source, thereby avoiding the compromise matching of parameters between optical illumination uniformity, illumination area and energy. A plurality of focusing lenses 3 can form a focusing lens array.

[0049] Among them, the lens is processed into a circular aperture, and then it is cut and polished into a rectangle as required to obtain the focusing lens 3 in this embodiment, and then the array layout is obtained by gluing two by two to form an integral part for assembly; the process is conventional and space-saving. During assembly, the lamp bead array is fixed as a whole at the bottom of the rectangular frame; a rectangular grid piece is installed at the front end of the lamp bead array, and inserted to fix the incident end of the light guide element 2; similarly, a rectangular grid piece is also installed near the exit surface 22 of the light guide element 2 to fix the exit end. Both grid pieces are fixed in the rectangular frame. The focusing lens 3 is fixed in the rectangular frame through the holes on the frame after pressing a circle of acrylic frame around it.

[0050] The solutions involved in the above embodiments are described in detail below in conjunction with specific embodiments.

[0051] like Figure 3 As shown, the UV LED lamp bead 1 used in a single UV LED edge exposure lamp has a divergence angle of about 70°, a radiation power of more than 5W, a light guide element 2 used in a quadrangular pyramid structure, and a light-transmitting surface of a focusing lens 3 used in a rectangular shape. After the UV light emitted by the UV LED lamp bead 1 with a divergence angle of about 70° passes through the light guide element 2, the exit angle is compressed to about 20°, and the energy utilization rate of the exit surface 22 reaches more than 80%.

[0052] When a 70mmx70mm illumination exposure is required at a working distance of 100mm, 25 UV LED edge exposure lamps are arranged in a 5x5 array channel to form a Figure 3 The multi-channel UV LED edge exposure assembly shown in the figure has a length of about 70mm from the UV LED lamp bead 1 to the focusing lens array optical part, and a width and height of about 80mmx80mm; the overall space is compact.

[0053] Figure 4 for Figure 3 The simulation results of the multi-channel UV LED edge exposure component are shown in the figure. Figure 4 In Figure 4 (a) and Figure 4 (b) is simulated using Tracepro software to measure the radiant illumination distribution on the exposed surface. Figure 4 (a) is an intuitive picture of the light radiation illumination. The color area represents the irradiated area of ​​70mmx70mm, and the left side of the color area is the color bar of energy. Figure 4 (b) is the contour curve of the light radiation illumination, the horizontal axis is the area size, and the vertical axis is the energy density value at different positions.

[0054] From the simulation results, the energy uniformity of the exposure area 70mmx70mm is greater than 90%, and the uniformity of the central area 50mmx50mm can be as high as 95%. At the exposure surface with a distance of 100mm from the focusing lens 3, the radiation power density can be as high as 1900mw / cm 2 above.

[0055] Among them, the key optical parameters of the edge exposure equipment are radiation power density, uniformity and illumination area. The radiation power density affects the intensity and speed of exposure. A higher radiation power density can shorten the exposure time and improve production efficiency. However, if the radiation power density is too high, it may cause overexposure of the photoresist, affecting product quality. Conversely, if the radiation power density is too low, it may cause underexposure, which also affects product quality. Therefore, the radiation power density needs to be precisely controlled according to the specific photoresist and process requirements to ensure the best exposure effect. Uniformity refers to the difference in exposure intensity at different positions from the center to the edge. Generally, uniformity ≥ 90% can ensure that the light intensity at each point during the edge exposure process is consistent, which is crucial to maintaining product quality and consistency. The size of the exposure area directly affects the efficiency and output of the exposure. A larger exposure area can improve production efficiency, but at the same time, a higher radiation power density is required to ensure exposure performance. These main optical parameters and indicators jointly ensure the accuracy and efficiency of edge exposure during the display panel manufacturing process. It can be seen from the above simulation that the radiation power density, uniformity and illumination area of ​​the multi-channel UV LED edge exposure component in this embodiment meet the requirements.

[0056] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A UV LED edge exposure lamp, characterized in that: It comprises a UV LED lamp bead (1), a light guide element (2) and a focusing lens (3); wherein: The light guide element (2) is in the shape of a prism, with a small end surface being an incident surface (21) and a large end surface being an exit surface (22), the incident surface (21) facing the UV LED lamp bead (1), and the exit surface (22) facing the focusing lens (3); The light guide element (2) is used to homogenize the light emitted by the UV LED lamp bead (1); the focusing lens (3) is used to focus the light emitted by the light guide element (2), with the focusing surface of the focusing lens (3) serving as an exposure area.

2. The UV LED edge exposure lamp according to claim 1, characterized in that: The light guide element (2) is in the shape of a quadrangular pyramid, and the light passing surface of the focusing lens (3) is rectangular.

3. The UV LED edge exposure lamp according to claim 2, characterized in that: The light-emitting surface of the UV LED lamp bead (1) is rectangular.

4. The UV LED edge exposure lamp according to claim 1, characterized in that: The exit surface (22) of the light-guiding element (2) is proportionally enlarged relative to the incident surface (21), and the side length enlargement factor is ≥3.

5. The UV LED edge exposure lamp according to claim 1, characterized in that: The incident surface (21) of the light guide element (2) is a concave surface.

6. The UV LED edge exposure lamp according to claim 1, characterized in that: The incident surface (21) of the light guide element (2) is in close contact with the UV LED lamp bead (1) and completely covers the light emitting surface of the UV LED lamp bead (1).

7. The UV LED edge exposure lamp according to claim 1, characterized in that: The incident surface (21) and the exit surface (22) are respectively coated with UV anti-reflection films.

8. The UV LED edge exposure lamp according to claim 1, characterized in that: The focusing lens (3) is coated with a UV anti-reflection film layer.

9. The UV LED edge exposure lamp according to claim 1, characterized in that: The focusing lens (3) is a plano-convex lens.

10. A multi-channel UV LED edge exposure assembly, characterized in that: It comprises a plurality of UV LED edge exposure lamps as described in any one of claims 1 to 9, wherein the focusing lenses (3) of the plurality of UV LED edge exposure lamps are spliced ​​with each other.

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