Light guide plate

Abstract

The invention relates to the technical field of lamps, and provides a light guide plate. The light guide plate is in a long strip shape, the two ends of the light guide plate in the length direction are provided with a light inlet face and a return structure respectively, and the return structure comprises at least one light return block. The light returning block is provided with a first reflecting surface and a second reflecting surface which are opposite, and the interval between the first reflecting surface and the second reflecting surface is gradually reduced in the direction away from the light incident surface. The two opposite sides of the light guide plate in the thickness direction are provided with a reflection structure and a light-emitting face respectively. Light enters the light guide plate through the light-in surface, part of the light is reflected to the light-out surface through the reflection structure to be emitted, and part of the light reaches the first reflection surface or the second reflection surface and is reflected back into the light guide plate. The first reflecting surface and the second reflecting surface of the light returning block reflect the light reaching the position back into the light guide plate, the first reflecting surface and the second reflecting surface are gradually folded, the light at the tail of the light guide plate is collected and reflected, the energy utilization rate of light is improved, and the brightness of an irradiation area is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of lamps, and in particular to a light guide plate. Background Art

[0002] A light guide plate is a structural component that guides the light emitted by an LED (Light Emitting Diode) to the location where the light is emitted. The light guide plate is made of a material with good light-guiding properties, such as polycarbonate or acrylic. Due to its superior light-guiding properties, the light guide plate is commonly used in lamps, signal indicators and other fields.

[0003] The existing automotive atmosphere light comprises a lamp bead and a light guide plate. After the light emitted by the lamp bead passes through the light guide plate, part of the light is emitted from the irradiated area and part of the light is emitted from the non-irradiated area, resulting in energy waste. Summary of the invention

[0004] The object of the present invention is to provide a light guide plate, aiming to solve the technical problem that the energy utilization rate of the existing light guide plate needs to be improved.

[0005] The present application provides a light guide plate, which is in the shape of a long strip, and has a light incident surface and a return structure at both ends of the length direction, and the return structure includes at least one light return block. The light return block has a first reflection surface and a second reflection surface opposite to each other, and the interval between the first reflection surface and the second reflection surface gradually decreases in the direction away from the light incident surface. The light guide plate has a reflection structure and a light emitting surface at two opposite sides in the thickness direction;

[0006] The light enters the light guide plate through the light incident surface, part of the light is reflected by the reflective structure to be emitted from the light emitting surface, and part of the light reaches the first reflective surface or the second reflective surface and is reflected back into the interior of the light guide plate.

[0007] In one of the embodiments, the acute angle between the first reflective surface and the length direction is substantially smaller than the critical angle of total reflection of light emitted from the light guide plate into the air.

[0008] In one of the embodiments, the acute angle between the second reflective surface and the length direction is substantially smaller than the critical angle of total reflection of light emitted from the light guide plate into the air.

[0009] In one embodiment, the first reflective surface is a plane.

[0010] In one embodiment, the acute angle between the first reflective surface and the length direction is smaller than the critical angle of total reflection of light emitted from the light guide plate into the air.

[0011] In one embodiment, the acute angle between the first reflecting surface and the length direction is greater than 2 / 3 of the critical angle of total reflection.

[0012] In one embodiment, the acute angle between the first reflecting surface and the length direction is greater than 4 / 5 of the critical angle of total reflection.

[0013] In one embodiment, the second reflective surface is a plane.

[0014] In one embodiment, the acute angle between the second reflective surface and the length direction is smaller than the critical angle of total reflection of light emitted from the light guide plate into the air.

[0015] In one embodiment, the acute angle between the second reflection surface and the length direction is greater than 2 / 3 of the critical angle of total reflection.

[0016] In one embodiment, the acute angle between the second reflection surface and the length direction is greater than 4 / 5 of the critical angle of total reflection.

[0017] In one embodiment, the first reflective surface and the second reflective surface are arranged opposite to each other along the width direction of the light guide plate.

[0018] In one embodiment, there are multiple light return blocks, and the multiple light return blocks are distributed in sequence along the width direction.

[0019] In one embodiment, one end of the first reflection surface of the latter light return block is spliced ​​with the second reflection surface of the former light return block, and one end of the first reflection surface of the latter light return block is spliced ​​with the second reflection surface of the light return block.

[0020] In one embodiment, the first reflecting surface and the second reflecting surface are arranged opposite to each other along the thickness direction.

[0021] In one embodiment, the number of the light return block is one, one end of the first reflective surface is spliced ​​with the light emitting surface, and the other end of the first reflective surface is spliced ​​with the second reflective surface.

[0022] In one embodiment, the reflective structure includes a plurality of reflective portions, the plurality of reflective portions are spaced apart along the length direction, and each of the reflective portions has a reflective spherical surface.

[0023] In one embodiment, the reflective arc surface is convexly arranged away from the light emitting surface, or concavely arranged close to the light emitting surface.

[0024] In one of the embodiments, the reflective structure comprises a cylindrical groove extending along the length direction, and a groove bottom of the cylindrical groove is provided with a plurality of arc grooves spaced apart along the length direction.

[0025] In one of the embodiments, the width dimension of the light guide plate is greater than three times the thickness dimension of the light guide plate, the number of the reflective structures is more than two, and all the reflective structures are spaced apart and distributed along the width direction.

[0026] The beneficial effect of the light guide plate provided by the present invention is as follows: compared with a case where the light guide plate is not provided with a return structure, when the light reaches the end of the light guide plate away from the light incident surface, it will be directly refracted out, and the exit position is not the irradiation area, resulting in a waste of light energy. The light guide plate provided by the present application is provided with a return structure, and the first reflection surface and the second reflection surface of the light return block reflect the light reaching this position back to the interior of the light guide plate, and then directly through the light exit surface, or first through the reflection structure and then finally through the light exit surface to the irradiation area, thereby improving the energy utilization rate of the light, solving the technical problem that the energy utilization rate of the existing light guide plate needs to be improved, and increasing the brightness of the irradiation area. The first reflection surface and the second reflection surface gradually close together, collect and reflect the light at the tail of the light guide plate, and further improve the utilization rate of light energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 A schematic diagram of the use of the first light guide plate provided by an embodiment of the present invention;

[0029] Figure 2 for Figure 1 A local enlarged view of point A;

[0030] Figure 3 for Figure 1 A schematic diagram of the structure of the light guide plate in FIG.

[0031] Figure 4 for Figure 3 A local enlarged view of point B in FIG.

[0032] Figure 5 for Figure 1 Another perspective view of the light guide plate in FIG.

[0033] Figure 6 for Figure 1 Schematic diagram of light spot simulation of the light guide plate;

[0034] Figure 7 A schematic diagram of the use of a second light guide plate provided in an embodiment of the present invention;

[0035] Figure 8 for Figure 7 A local enlarged view of point C in FIG.

[0036] Fig. 9 for Figure 7 A schematic diagram of the structure of the light guide plate in FIG.

[0037] Fig.10 for Fig. 9 A local enlarged view of point D in FIG.

[0038] Fig.11 for Figure 7 Another perspective view of the light guide plate in FIG.

[0039] Fig.12 for Figure 7 Schematic diagram of light spot simulation of the light guide plate;

[0040] Fig.13 is a structural schematic diagram of a first light guide plate in the related art;

[0041] Fig.14 for Fig.13 Schematic diagram of light spot simulation of the light guide plate;

[0042] Fig.15 A partial schematic diagram of a third light guide plate provided by an embodiment of the present invention;

[0043] Fig.16 for Fig.15 A cross-sectional view of the light guide plate along line NN;

[0044] Fig.17 for Fig.15 A cross-sectional view of the light guide plate along line MM;

[0045] Fig.18 for Fig.15 Schematic diagram of light spot simulation of the light guide plate;

[0046] Fig.19 A partial schematic diagram of a fourth light guide plate provided by an embodiment of the present invention;

[0047] Fig. 20 for Fig.19 Schematic diagram of light spot simulation of the light guide plate;

[0048] Fig.21 is a structural schematic diagram of a second light guide plate in the related art;

[0049] Fig. 22 for Fig.21Schematic diagram of light spot simulation of the light guide plate in FIG.

[0050] Among them, the reference numerals in the figure are:

[0051] X, length direction; Y, width direction; Z, thickness direction;

[0052] 1. Light guide plate; 2. Lamp beads; 3. Target surface;

[0053] 10. Light incident surface; 20. Return structure; 21. Return light block; 22. First reflection surface; 23. Second reflection surface; 24. First auxiliary block; 25. Third reflection surface; 26. Second auxiliary block; 27. Fourth reflection surface; 30. Reflection structure; 31. Reflection part; 32. Reflection spherical surface; 33. Cylindrical groove; 34. Arc groove; 40. Light emitting surface; 50. First side surface; 60. Second side surface. DETAILED DESCRIPTION

[0054] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0055] Reference throughout the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, when the phrases "in one embodiment" or "in some embodiments" appear in various places throughout the specification, not all references are to the same embodiment. Furthermore, in one or more embodiments, the particular features, structures, or characteristics may be combined in any suitable manner.

[0056] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0057] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0058] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] Figure 1 A schematic diagram of the use of the first light guide plate 1 provided in an embodiment of the present invention, Figure 6 This is a schematic diagram of the use of the second light guide plate 1 provided in an embodiment of the present invention.

[0060] Combination Figure 1 and Figure 6 The light guide plate 1 provided in the present application is in the shape of a long strip, and a light incident surface 10 and a return structure 20 are respectively provided at both ends of the light guide plate 1 in the length direction X, and the return structure 20 includes at least one light return block 21. The light return block 21 has a first reflection surface 22 and a second reflection surface 23 opposite to each other, and the light guide plate 1 has a reflection structure 30 and a light emitting surface 40 on opposite sides in the thickness direction Z.

[0061] Specifically, the lamp bead 2 is arranged on the light incident surface 10. The light emitted by the lamp bead 2 enters the light guide plate 1 through the light incident surface 10, part of the light is reflected by the reflective structure 30 to the light emitting surface 40, and part of the light reaches the first reflective surface 22 or the second reflective surface 23 and is reflected back to the inside of the light guide plate 1, and then directly passes through the light emitting surface 40, or first passes through the reflective structure 30 and then finally passes through the light emitting surface 40 to the irradiation area, thereby improving the energy utilization rate of the light and increasing the brightness of the irradiation area.

[0062] Among them, the interval between the first reflecting surface 22 and the second reflecting surface 23 gradually decreases in the direction away from the light incident surface 10, and the first reflecting surface 22 and the second reflecting surface 23 gradually close together. The first reflecting surface 22 and the second reflecting surface 23 collect and reflect the light reaching the tail of the light guide plate 1, further improving the utilization rate of light energy.

[0063] Fig.11 FIG. 1 is a schematic diagram of the structure of a light guide plate 1 in the related art. Fig.11 If the return structure 20 is not provided at the tail of the light guide plate 1, that is, the end of the light guide plate 1 away from the light incident surface 10 is a plane. For a shorter light guide plate 1 structure, a portion of the energy will be directly emitted from the light guide plate 1, resulting in energy waste. The irradiation area directly facing the light exiting surface 40 has a reduced brightness due to light loss.

[0064] Fig.14The simulation results of the light guide plate 1 without the return structure 20 are shown, and the average illumination of the irradiated area is 2178.66 lx, and the luminous flux is 9.58609 lm. Figure 6 The display sets the return structure 20 as a simulation structure of multiple return light blocks 21, only the tail is modified to multiple return light blocks 21, Figure 6 The light guide plate 1 and Fig.14 There is no other difference in the light guide plate 1. The average illumination of the illuminated area of ​​the same area is 2354.63lx, and the luminous flux is 10.3604lm. Fig.12 The display shows the simulated structure of setting the return structure 20 as a single return light block 21, only the tail is modified to a single return light block 21, Fig.12 The light guide plate 1 and Fig.14 The light guide plate 1 has no other difference, and the average illumination of the irradiated area of ​​the same area is 2379.58 lx, and the luminous flux is 10.4701 lm. It can be concluded that the light guide plate 1 is designed with the return structure 20, and the energy utilization rate is improved by 8% to 9%.

[0065] In this embodiment, the first reflection surface 22 and the second reflection surface 23 of the light return block 21 are gradually closed within the original thickness range of the light guide plate 1, so no extra space is occupied. The return structure 20 is slightly modified, and the modification occupies little space, and no extra space is occupied.

[0066] In some embodiments, in combination Figure 3 and Fig. 9 , the light guide plate 1 is made of transparent resin. The transparent resin has good optical properties, can effectively transmit light, reduce light loss, and help improve the light energy utilization rate of the light guide plate 1. The resin material can be formed by injection molding, extrusion and other processes, and can achieve complex shape design.

[0067] In some embodiments, in combination Figure 5 and Fig.11 , the light guide plate 1 is integrally formed. The integrally formed light guide plate 1 has no seams or splicing, which can improve the overall structural strength and stability, reduce light leakage or structural weaknesses that may occur at the seams, and improve the energy utilization of light. The integrally formed light guide plate 1 can maintain consistent optical performance and physical properties during the production process, reducing performance fluctuations caused by assembly errors.

[0068] In some embodiments, in combination Figure 5 and Fig. 9 The light incident surface 10 is a plane, which simplifies the introduction of light. The plane can reduce the scattering and reflection of light, so that more light can be effectively guided into the light guide plate 1. It can be understood that in other embodiments, the light incident surface 10 can also be a curved surface, such as an inner concave curved surface or an outer convex curved surface, which is not limited here.

[0069] In some embodiments, in combination Figure 3 and Figure 6 , the light guide plate 1 has a first side surface 50 and a second side surface 60 on both sides in the width direction Y, respectively. The first side surface 50 and the second side surface 60 are connected to the light emitting surface 40 and the bottom surface in the thickness direction Z, respectively. The bottom surface is provided with a reflective structure 30, and is connected to the light incident surface 10 and the return structure 20 in the length direction X. The light guide plate 1 has a first side surface 50 and a second side surface 60 on both sides in the width direction Y, respectively. The first side surface 50 and the second side surface 60 are connected to the light emitting surface 40 and the bottom surface in the thickness direction Z, respectively. The bottom surface is provided with a reflective structure 30, and is connected to the light incident surface 10 and the return structure 20 in the length direction X. Based on this, the light emitting surface 40 and the bottom surface occupy the entire width dimension, realizing the maximum area design of the light emitting surface 40 and increasing the irradiation area. The two sides of the width of the return structure 20 abut the first side surface 50 and the second side surface 60, respectively, realizing the maximum area of ​​light return utilization and increasing the energy utilization rate.

[0070] Specifically, the first side surface 50 is a plane, and the first side surface 50 with a plane design simplifies the manufacturing and splicing process of the light guide plate 1, thereby helping to reduce production costs. The first side surface 50 with a plane design makes it easy to achieve plane fitting and splicing between two light guide plates 1. In other words, multiple light guide plates 1 can be used in combination, and multiple light guide plates 1 are spaced apart along the width direction Y. The irradiation areas of multiple light guide plates 1 are spliced ​​along the width direction Y, further expanding the irradiation area and improving uniform light emission.

[0071] Specifically, the second side surface 60 is a plane, and the second side surface 60 with a plane design simplifies the manufacturing and splicing process of the light guide plate 1, thereby helping to reduce production costs. The second side surface 60 with a plane design makes it easy to achieve plane fitting and splicing between two light guide plates 1. In other words, multiple light guide plates 1 can be used in combination, and multiple light guide plates 1 are spaced apart along the width direction Y. The irradiation areas of multiple light guide plates 1 are spliced ​​along the width direction Y, further expanding the irradiation area and improving uniform light emission.

[0072] In some embodiments, in combination Figure 4 and Figure 8 The ends of the first reflecting surface 22 and the second reflecting surface 23 are spliced ​​together to form a complete and continuous reflecting surface, thereby ensuring that the light can be more effectively utilized after multiple reflections inside the light guide plate 1, thereby reducing light energy loss.

[0073] The end of the first reflective surface 22 refers to an end of the first reflective surface 22 away from the light incident surface 10 . The end of the second reflective surface 23 refers to an end of the second reflective surface 23 away from the light incident surface 10 .

[0074] Specifically, combined Figure 4 and Figure 8, the first reflection surface 22 and the second reflection surface 23 are symmetrically distributed about the splicing plane. The symmetrically distributed first reflection surface 22 and the second reflection surface 23 can more effectively guide the light to propagate in a predetermined direction, which helps to improve the lighting effect, so that the light can be more accurately irradiated to the irradiation area. Since the light can be more evenly distributed on the light emitting surface 40 after multiple reflections inside the light guide plate 1, the symmetrically distributed first reflection surface 22 and the second reflection surface 23 help to improve the brightness uniformity.

[0075] In some embodiments, in combination Figure 2 and Figure 8 , the acute angle between the first reflection surface 22 and the length direction X is substantially smaller than the critical angle of total reflection of light from the light guide plate 1 into the air. The return structure 20 only utilizes the principle of total reflection of light, that is, when light is incident from a dense medium into a sparse medium, and the incident angle is greater than or equal to the critical angle, the light will be totally reflected at the junction of the two media, and will not enter the sparse medium. Since the direction of the light reaching the first reflection surface 22 is substantially parallel to the length direction X, that is, it can be substantially totally reflected back into the light guide plate 1, fully utilizing the energy and improving the utilization rate of light.

[0076] The first reflective surface 22 can be a curved surface or a flat surface, which is not limited here. When the first reflective surface 22 is a curved surface, substantially less than the critical angle of total reflection means that the acute angle between more than 60% of the area of ​​the first reflective surface 22 and the length direction X is less than the critical angle of total reflection.

[0077] In one embodiment, in combination Figure 4 and Fig.11 The first reflection surface 22 is a plane. First, the light can be reflected back into the light guide plate 1 more effectively without losing energy due to scattering or refraction caused by the curved surface. Second, it is relatively easy to predict and control, which is conducive to simplifying the optical path design of the light guide plate 1. Third, it reduces the production cost.

[0078] Specifically, the acute angle between the first reflection surface 22 and the length direction X is smaller than the critical angle of total reflection of light emitted from the light guide plate 1 into the air. Light incident parallel to the length direction X will be totally reflected on the first reflection surface 22, thereby improving the utilization rate of light and allowing more light to reach the light output surface 40, thereby enhancing the lighting effect.

[0079] Specifically, the acute angle between the first reflection surface 22 and the length direction X is greater than 2 / 3 of the critical angle of total reflection. That is, the first reflection surface 22 has a large inclination angle toward the second reflection surface 23, and can quickly close with the second reflection surface 23, greatly reducing the size of the return light block 21 in the length direction X, so that the added return structure 20 occupies a small space, and Fig.13 The light guide plate 1 in FIG. 1 is almost the same and does not take up additional space.

[0080] Furthermore, the acute angle between the first reflection surface 22 and the length direction X is greater than 4 / 5 of the critical angle of total reflection, thereby greatly reducing the size of the return light block 21 in the length direction X, making the space occupied by the entire return structure 20 smaller, further improving the space utilization. The first reflection surface 22 with a larger inclination angle can more accurately control the propagation path of the light, so that the light can be reflected and propagated in a predetermined direction.

[0081] In some embodiments, in combination Figure 4 and Fig.11 The acute angle between the second reflection surface 23 and the length direction X is substantially smaller than the critical angle of total reflection of light from the light guide plate 1 into the air. Since the direction of the light reaching the second reflection surface 23 is substantially parallel to the length direction X, that is, it can be substantially totally reflected back into the light guide plate 1, the utilization rate of the light is improved.

[0082] The second reflective surface 23 can be a curved surface or a flat surface, which is not limited here. When the second reflective surface 23 is a curved surface, substantially less than the critical angle of total reflection means that the acute angle between more than 60% of the area of ​​the second reflective surface 23 and the length direction X is less than the critical angle of total reflection.

[0083] In some embodiments, in combination Figure 4 and Fig.11 The second reflecting surface 23 is a plane. First, the light can be reflected back into the light guide plate 1 more effectively without losing energy due to scattering or refraction caused by the curved surface. Second, it is relatively easy to predict and control, which is conducive to simplifying the optical path design of the light guide plate 1. Third, it reduces the production cost.

[0084] In one of the embodiments, the acute angle between the second reflection surface 23 and the length direction X is smaller than the critical angle of total reflection of light emitted from the light guide plate 1 into the air, and the light incident parallel to the length direction X will be totally reflected on the second reflection surface 23, thereby improving the utilization rate of the light and allowing more light to reach the light output surface 40, thereby enhancing the lighting effect.

[0085] In one embodiment, the acute angle between the second reflection surface 23 and the length direction X is greater than 2 / 3 of the critical angle of total reflection. That is, the second reflection surface 23 has a large inclination angle toward the first reflection surface 22, and can quickly close with the first reflection surface 22, greatly reducing the size of the return light block 21 in the length direction X, so that the added return structure 20 occupies a small space, and Fig.13 The light guide plate 1 in FIG. 1 is almost the same and does not take up additional space.

[0086] In one embodiment, the acute angle between the second reflection surface 23 and the length direction X is greater than 4 / 5 of the critical angle of total reflection, thereby greatly reducing the size of the light return block 21 in the length direction X, making the space occupied by the entire return structure 20 smaller, further improving the space utilization. The second reflection surface 23 with a larger inclination angle can more accurately control the propagation path of the light, so that the light can be reflected and propagated in a predetermined direction.

[0087] In some embodiments, in combination Figures 1 to 5 Since the width of the light guide plate 1 is greater than its height, the first reflection surface 22 and the second reflection surface 23 are relatively arranged along the width direction Y of the light guide plate 1, so that the light has enough width to design the reflection light path, and finally reaches the light output surface 40 instead of the first side surface 50 or the second side surface 60. At the same time, the reflection uniformity of the return structure 20 in the width direction Y is increased, the occurrence of dark areas is reduced, and the uniformity and comfort of lighting are improved.

[0088] Specifically, the first reflective surface 22 has smooth transitions with the light emitting surface 40 and the reflective structure 30 on both sides in the thickness direction Z. When light is transmitted from the first reflective surface 22 to the light emitting surface 40 or the reflective structure 30, if the transition is not smooth, the light may be scattered or reflected in the transition area, resulting in part of the light being unable to be transmitted along the predetermined path. At the same time, the first reflective surface 22 fully occupies the rear thickness space of the light guide plate 1 to prevent the light in the thickness direction Z from refracting and escaping.

[0089] Specifically, the second reflective surface 23 has smooth transitions with the light emitting surface 40 and the reflective structure 30 on both sides in the thickness direction Z. When light is transmitted from the second reflective surface 23 to the light emitting surface 40 or the reflective structure 30, if the transition is not smooth, the light may be scattered or reflected in the transition area, resulting in part of the light being unable to be transmitted along the predetermined path. At the same time, the second reflective surface 23 fully occupies the rear thickness space of the light guide plate 1 to prevent the light in the thickness direction Z from refracting and escaping.

[0090] In one embodiment, there are multiple light return blocks 21, and the multiple light return blocks 21 are sequentially distributed along the width direction Y. The multiple light return blocks 21 can make the first reflection surface 22 and the second reflection surface 23 alternately distributed, on the one hand, improve the reflection uniformity of the return structure 20 in the width direction Y, and finally improve the emission uniformity of the light output surface 40, on the other hand, due to the large width of the light guide plate 1, the multiple light return blocks 21 can reduce the size of a single first reflection surface 22 and a second reflection surface 23, thereby helping to reduce the size of the return structure 20 and the occupied space.

[0091] Specifically, the left and right sides of the light return block 21 are the first reflection surface 22 and the second reflection surface 23 respectively, and the upper and lower sides of the light return block 21 are smoothly transitioned with the light output surface 40 and the bottom surface respectively, to prevent light in the thickness direction Z from escaping from the return structure 20.

[0092] In one embodiment, in combination Figure 2 and Figure 4 The angle between the first reflecting surface 22 and the second reflecting surface 23 is a right angle, which ensures that the light will not deviate from the predetermined path during reflection, and the light can maintain a high reflection efficiency during the reflection process.

[0093] In one embodiment, one end of the first reflection surface 22 of the next light return block 21 is spliced ​​with the second reflection surface 23 of the previous light return block 21, and one end of the first reflection surface 22 of the next light return block 21 is spliced ​​with the second reflection surface 23 of the corresponding light return block 21. The splicing design reduces the scattering of light during the reflection process, and the splicing design helps to achieve a more uniform light distribution.

[0094] Specifically, combined Figure 3 and Figure 5 The return structure 20 includes a first auxiliary block 24, which is located on the side of the first return block 21 away from other return blocks 21. The first auxiliary block 24 has a first joint surface and a third reflection surface 25 in the width direction Y. The first joint surface and the first side surface 50 have a smooth transition to avoid light leakage, improve the size and coverage of the return structure 20 in the width direction Y, and improve energy utilization. The third reflection surface 25 is close to the first return block 21 and is used to achieve light reflection and energy utilization.

[0095] Optionally, one end of the third reflecting surface 25 is spliced ​​with the end of the first joint surface, and the other end is connected to the first reflecting surface 22 of the first light returning block 21, thereby increasing the coverage of the third reflecting surface 25 in the width direction Y, thereby improving the light returning effect of the returning structure 20 in the width dimension, and ensuring that the light can form a continuous reflection path in the returning structure 20.

[0096] Specifically, combined Figure 3 and Figure 5 The return structure 20 includes a second auxiliary block 26, which is located on the side of the last return block 21 away from other return blocks 21. The second auxiliary block 26 has a second joint surface and a fourth reflection surface 27 in the width direction Y. The second joint surface and the second side surface 60 have a smooth transition to avoid light leakage, improve the size and coverage of the return structure 20 in the width direction Y, and improve energy utilization. The fourth reflection surface 27 is close to the first return block 21 and is used to achieve light reflection and energy utilization.

[0097] Optionally, one end of the fourth reflecting surface 27 is spliced ​​with the end of the second joint surface, and the other end is connected to the second reflecting surface 23 of the last light returning block 21, thereby increasing the coverage of the fourth reflecting surface 27 in the width direction Y, thereby improving the light returning effect of the returning structure 20 in the width dimension, and ensuring that the light can form a continuous reflection path in the returning structure 20.

[0098] In some embodiments, in combination Figures 7 to 11 The first reflecting surface 22 and the second reflecting surface 23 are arranged opposite to each other along the thickness direction Z, so that the first reflecting surface 22 and the second reflecting surface 23 can extend along the width direction Y, thereby expanding the areas of the first reflecting surface 22 and the second reflecting surface 23. Therefore, the large-area first reflecting surface 22 and the second reflecting surface 23 can increase the light returning effect, reduce the light leakage of the splicing gap, and improve the energy utilization rate of light.

[0099] In addition, the first reflection surface 22 and the second reflection surface 23 are distributed in sequence along the thickness direction Z, and the light emitting surface 40 and the reflection structure 30 are also distributed in sequence along the thickness direction Z. The first reflection surface 22 and the second reflection surface 23 can receive the light reflected and deviated by the light emitting surface 40 and the reflection structure 30, and will return it again along the thickness direction Z, so as to finally be uniformly emitted from the light emitting surface 40.

[0100] In one embodiment, in combination Figures 7 to 11 , the number of the light return block 21 is one, one end of the first reflection surface 22 is spliced ​​with the light emitting surface 40, and the other end of the first reflection surface 22 is spliced ​​with the second reflection surface 23, which can minimize the light leakage from between the first reflection surface 22 and the second reflection surface 23. Since the number of the light return block 21 is one, and the splicing design between the first reflection surface 22 and the second reflection surface 23 and between them and the light emitting surface 40 is relatively simple, the number of splicing gaps can be reduced, which helps to reduce the light leakage caused by the splicing gaps and improve the energy utilization rate of light.

[0101] Specifically, the other end of the second reflective surface 23 is spliced ​​with the bottom surface of the light guide plate 1 to achieve a maximized design of the second reflective surface 23 in the thickness direction Z, enhance the light return effect, and the second reflective surface 23 is directly spliced ​​with the bottom surface of the light guide plate 1, reducing additional splicing gaps.

[0102] Specifically, the first reflecting surface 22 is spliced ​​with the first side surface 50 and the second side surface 60 on both sides in the width direction Y, respectively, so as to maximize the width dimension of the first reflecting surface 22 and improve the coverage of the reflection.

[0103] Specifically, the second reflecting surface 23 is spliced ​​with the first side surface 50 and the second side surface 60 on both sides in the width direction Y, respectively, so as to maximize the width dimension of the second reflecting surface 23 and improve the coverage of reflection.

[0104] In some embodiments, in combination Figure 4 and Fig.10 The reflective structure 30 includes a plurality of reflective parts 31, and the plurality of reflective parts 31 are spaced apart along the length direction X, and each reflective part 31 has a reflective spherical surface 32. The surface of the reflective spherical surface 32 is smooth, and there are no edge protrusions, so that most of the light is totally reflected and propagates toward the light exiting surface 40. The spherical surface design can more effectively receive and reflect light, and reduce the scattering and loss of light. The plurality of reflective parts 31 are spaced apart along the length direction X, which helps to distribute the light more evenly inside the light guide plate 1. The reflective spherical surface 32 of each reflective part 31 can guide the light to different directions, thereby ensuring that the light can be evenly irradiated to various parts of the light guide plate 1.

[0105] Specifically, the distance between the spherical centers of two adjacent reflecting spherical surfaces 32 in the length direction X is equal to 80% to 120% of the sum of the spherical radii corresponding to the two reflecting spherical surfaces 32. Therefore, in the light-emitting surface 40, the area facing the reflecting spherical surface 32 and the area between the two reflecting spherical surfaces 32 can receive the light reflected by the reflecting part 31, thereby enhancing the uniformity of the light and achieving no difference in brightness or darkness in the illuminated area.

[0106] Specifically, the spherical radius corresponding to the reflecting spherical surface 32 is equal to 40% to 60% of the thickness of the light guide plate 1, that is, the spherical radius of the reflecting spherical surface 32 matches the thickness of the light guide plate 1, avoiding the phenomenon of "darkness under the lamp", and the light can be more evenly irradiated to various parts of the light output surface 40, reducing the generation of dark areas.

[0107] In one embodiment, in combination Figure 4 and Fig.10 , the reflective arc surface is convexly arranged away from the light emitting surface 40. The convexly arranged reflective arc surface will not occupy the internal space of the light guide plate 1, is suitable for a light guide plate 1 with a relatively thin thickness, will not block the propagation of light along the length direction X, and realizes a more uniform light emission of the light guide plate 1 in the length direction X. The convexly arranged reflective arc surface can distribute the light more evenly to the entire lighting area, reduce dark areas and bright spots, and improve the overall quality of lighting.

[0108] It is understood that in other embodiments, the reflective arc surface is recessed toward the light-emitting surface 40. The recessed reflective arc surface does not occupy external space, and avoids damage caused by friction with external components. The light reflected by the concave reflective arc surface is distributed divergently, does not cross each other, and emits light more evenly.

[0109] In some embodiments, in combination Fig.15 , Fig.16 and Fig.17The reflective structure 30 includes a cylindrical groove 33 extending along the length direction X, and a plurality of arc grooves 34 are arranged at the bottom of the cylindrical groove 33 and are spaced apart along the length direction X. The arc groove 34 has a large surface area compared to a plane, which is conducive to reflecting light in all directions. When viewed from the outside of the light guide plate 1, the bottom of the arc groove 34 is concave, but when viewed from the outside of the light guide plate 1, the bottom of the arc groove 34 is concave. Based on this, the cylindrical groove 33 and the arc groove 34 are processed by removing materials, and then a plurality of arc grooves 34 are spaced apart along the length direction X are formed, which simplifies the manufacturing process, helps to reduce manufacturing costs, improve production efficiency, and makes the light guide plate 1 easier to integrate and install.

[0110] In addition, the curvature of the circular arc groove 34 is consistent, which can evenly reflect the light along each radial direction, thereby improving the uniformity of light reflection. Optionally, the arc angle of the circular arc groove 34 is 180°.

[0111] In one embodiment, transition fillets are provided on both sides of the arc groove 34 in the length direction X to reduce the sudden change of light at the edge of the arc groove 34, so that the light reflected by the arc groove 34 is more uniform and soft in the length direction X, and the light reflected to the light emitting surface 40 is evenly distributed in the length direction X. In addition, the transition fillets help reduce light loss and improve light transmission efficiency.

[0112] Fig.15 The light guide plate 1 having the arc groove 34 has two planes on both sides in the width direction Y, and the light emitting surface 40 is a plane, that is, the light guide plate 1 has a square main structure and a bamboo-shaped reflective structure 30 .

[0113] Combination Fig.16 When light is irradiated to the arc groove 34, because the arc groove 34 is arc-shaped, the light will be totally reflected along the plane perpendicular to the arc, presenting a fan-shaped emission area, so that the entire light-emitting surface 40 can be irradiated, forming a uniform illumination on the target surface 3. Further, by appropriately adjusting the radius, depth and other factors of the cylindrical groove 33, the size of the light-emitting surface 40 can be controlled, so that the illumination of the target surface 3 is uniform;

[0114] Combination Fig.17 When the lamp bead 2 emits light into the light guide plate 1, most of the light is totally reflected in the light guide plate 1, causing the light to propagate along the length direction X. The arc groove 34 can change the propagation direction of the light, break the total reflection phenomenon, and allow a small part of the light to be emitted from the light emitting surface 40. By properly adjusting the spacing, size, depth and other factors of the arc grooves 34, the light output of each arc groove 34 is controlled, thereby achieving uniform illumination of the target surface 3.

[0115] Fig.18It is a simulation schematic diagram of a light guide plate 1 having a single row of arc grooves 34 . Fig.18 The right picture in the figure is the illumination analysis of the slice at the vertical white line position in the left picture.

[0116] Fig.21 A cylindrical light guide plate 1 is shown, the bottom surface of which is a plane and a strip-shaped convex reflective structure 30 is provided. Fig. 22 A simulated schematic diagram of a light guide plate 1 having a cylindrical body. Fig. 22 The right picture in the figure is the illumination analysis of the slice at the vertical white line position in the left picture.

[0117] contrast Fig.18 and Fig. 22 It can be seen that the light guide plate 1 with a single row of arc grooves 34 has a wider area corresponding to the irradiation region and a more uniform illumination, which has obvious advantages in near-field applications.

[0118] In some embodiments, in combination Figure 3 , Fig. 9 and Fig.19 , the width of the light guide plate 1 is greater than three times the thickness of the light guide plate 1, and the number of the reflective structures 30 is more than two. All the reflective structures 30 are spaced apart along the width direction Y, which helps to distribute the light more evenly over the entire target surface 3, reduces the possibility of light overlap or dark areas in the width direction Y, and makes the lighting more uniform and soft.

[0119] Fig.19 The light guide plate 1 in FIG. 1 includes five reflective structures 30 distributed at intervals along the width direction Y. As shown in FIG. Fig. 20 is a simulation schematic diagram of the light guide plate 1, Fig. 20 It shows that the expanded area still has uniform illumination, so uniform illumination can be achieved in a rectangular area of ​​a certain area. Based on this, the light guide plate 1 can achieve the expansion of the illuminated target surface 3 by properly adjusting the spacing between the reflective structures 30 without uneven illumination.

[0120] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A light guide plate, characterized in that: The light guide plate is in the shape of a long strip, and a light incident surface and a return structure are respectively arranged at two ends of the light guide plate in the length direction, and the return structure includes at least one light return block; the light return block has a first reflection surface and a second reflection surface opposite to each other, and the interval between the first reflection surface and the second reflection surface gradually decreases in the direction away from the light incident surface; the light guide plate has a reflection structure and a light emitting surface at two opposite sides in the thickness direction; The light enters the light guide plate through the light incident surface, part of the light is reflected by the reflective structure to be emitted from the light emitting surface, and part of the light reaches the first reflective surface or the second reflective surface and is reflected back into the interior of the light guide plate.

2. The light guide plate according to claim 1, characterized in that: The acute angle between the first reflecting surface and the length direction is substantially smaller than the critical angle of total reflection of light emitted from the light guide plate into the air; And / or, the acute angle between the second reflective surface and the length direction is substantially smaller than the critical angle of total reflection of light emitted from the light guide plate into the air.

3. The light guide plate according to claim 1, characterized in that: The first reflecting surface is a plane; the acute angle between the first reflecting surface and the length direction is smaller than the critical angle of total reflection of light emitted from the light guide plate into the air; The acute angle between the first reflecting surface and the length direction is greater than 2 / 3 of the critical angle of total reflection.

4. The light guide plate according to claim 1, characterized in that: The second reflecting surface is a plane; the acute angle between the second reflecting surface and the length direction is smaller than the critical angle of total reflection of light emitted from the light guide plate into the air; The acute angle between the second reflection surface and the length direction is greater than 2 / 3 of the critical angle of total reflection.

5. The light guide plate according to claim 1, characterized in that: The first reflecting surface and the second reflecting surface are arranged opposite to each other along a width direction of the light guide plate.

6. The light guide plate according to claim 5, characterized in that: There are multiple light return blocks, and the multiple light return blocks are distributed in sequence along the width direction; One end of the first reflection surface of the next light return block is spliced ​​with the second reflection surface of the previous light return block, and one end of the first reflection surface of the next light return block is spliced ​​with the second reflection surface of the light return block.

7. The light guide plate according to claim 1, characterized in that: The first reflecting surface and the second reflecting surface are arranged opposite to each other along the thickness direction.

8. The light guide plate according to claim 7, characterized in that: The number of the light return block is one, one end of the first reflective surface is spliced ​​with the light emitting surface, and the other end of the first reflective surface is spliced ​​with the second reflective surface.

9. The light guide plate according to any one of claims 1 to 8, characterized in that: The reflective structure comprises a plurality of reflective parts, the plurality of reflective parts are spaced apart along the length direction, and each of the reflective parts has a reflective spherical surface; the reflective arc surface is convexly arranged away from the light emitting surface, or concavely arranged close to the light emitting surface; Alternatively, the reflective structure comprises a cylindrical groove extending along the length direction, and a groove bottom of the cylindrical groove is provided with a plurality of arc grooves spaced apart along the length direction.

10. The light guide plate according to any one of claims 1 to 8, characterized in that: The width dimension of the light guide plate is greater than three times the thickness dimension of the light guide plate, the number of the reflective structures is more than two, and all the reflective structures are distributed at intervals along the width direction.

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