CN100444000C - Backlight module and its light source structure - Google Patents

Abstract

The invention discloses a backlight module and a light source structure thereof. The light-emitting element is arranged on the surface of the optical plate and has a light emitting direction. The light emitting direction and the surface of the optical plate form an included angle theta. The light-emitting element further comprises a light-emitting body and an encapsulating material, wherein the encapsulating material encapsulates the light-emitting body. The lens body is arranged on the surface and is connected with the optical plate and the light-emitting element. The lens body also comprises an inclined plane, one end of the inclined plane is connected with the light-emitting element, and the other end of the inclined plane is connected with the optical plate. The light emitting body is adjacent to the optical plate and the lens body. The invention overcomes the defects of the prior art, and provides a backlight module which uses light emitting diodes to make a light guide plate structure light-weight and thin and a light source structure thereof.

Description

Backlight module and its light source structure

technical field

The present invention relates to a backlight module and its light source structure, and in particular to a backlight module and its light source structure which use light emitting diode (LED, Light Emitting Diode) to make the light guide plate structure lightweight and thin.

Background technique

Since the light guide plate occupies a large proportion in the thickness and weight of the entire backlight module, facing the demand for thinner and lighter panels in the current panel market, the thinning of the light guide plate is an inevitable trend. However, with the current technology, the backlight module using light-emitting diodes as the light source cannot keep up with the speed of thinning the light guide plate. Diode thickness is 0.4mm. In particular, when the thinned light guide plate adopts the side light input method, the height of the light-emitting area of the LED will be greater than the thickness of the light guide plate, so that part of the light cannot enter the light guide plate, reducing the efficiency of light energy use. In addition, if the light guide plate is made by rolling or extrusion process, and each light guide plate of appropriate size is cut, the knife marks formed on the side of the light guide plate, and/or the dislocation or gap caused between the assembled LED and the light guide plate etc., will reduce the efficiency of incident light.

In view of the above situation, there is a light source structure of a thinned light guide plate in the known technology, as shown in FIG. 1 . The known light source structure 10 includes a light guide plate 12 , LEDs 14 and a wedge structure 16 . The wedge structure 16 is formed between the surface of the light guide plate 12 and the LED 14 . In other words, the light-incident side of the light-emitting diode 14 is designed to be wedge-shaped, so that the thickness of the light guide plate 12 and the thickness of the light-emitting diode 14 match each other, so as to avoid the problem of lower light energy usage efficiency.

However, the above structure will encounter a big difficulty in the manufacture of the thin light guide plate. In terms of injection molding, the thickness of the current injection technology is limited to 0.3mm, and the size of the thickness less than 0.3mm cannot be molded. In addition, if rolling or extruding is adopted, it is obviously impossible to achieve a finished product with a relatively thin flat plate on one side and a wedge-shaped structure on the other side.

Contents of the invention

The technical problem to be solved by the present invention is to provide a backlight source group and its light source structure which can effectively reduce the thickness and weight of the light guide plate.

Another object of the present invention is to provide a backlight group and a light source structure thereof which can increase the light energy usage efficiency.

Another object of the present invention is to provide a backlight module and its light source structure, which have the characteristics of improving the convenience of assembly and being easy to implement.

Another object of the present invention is to provide a backlight module capable of total reflection of light in the light guide plate and a light source structure thereof.

Another object of the present invention is to provide a backlight module and its light source structure for use with light emitting diodes.

The light source structure of the present invention includes an optical plate, a light emitting element and a lens body. The light emitting element is arranged on the surface of the optical plate. The light emitting element has a light emitting direction, and the light emitting direction forms an angle θ with the surface of the optical plate. The lens body is arranged on the surface and connected with the light emitting element. The lens body further includes a slope, one end of the slope is connected with the light-emitting element, and the other end is connected with the optical plate.

In a preferred embodiment, the refractive index n2 of the lens body is preferably between the refractive index n1 of the optical plate and the refractive index n3 of the light-emitting element, and the refractive index n1 of the optical plate is preferably greater than or equal to the light-emitting element. The refractive index n3 of the element. The light-emitting element further includes a luminous body and a packaging part, and the packaging part covers the luminous body. The luminous body is adjacent to the optical plate and the lens body. Preferably, the light source structure further includes a reflector. The reflection plate is preferably disposed on the bottom surface of the optical plate. There is a low refractive index layer between the optical plate and the reflection plate. The low refractive index layer is preferably air, and its refractive index is n4=1. The optical plate is preferably a light guide plate. According to Snall's law, the included angle θ is preferably less than or equal to sin ^-1 (n4/n1), so that the light emitting direction is totally reflected in the optical plate.

In addition, the light source structure further includes a frame, a circuit module and at least one microstructure. The frame is arranged on one end of the reflective plate, and is connected with the reflective plate through the adhesive layer. The circuit module is coupled to the light emitting element. Due to the design of different light source structures, the circuit module can be arranged on the upper surface, the side surface or the lower surface of the light emitting element. What's more, the circuit module can be arranged between the surface of the light-emitting element and the optical plate. The circuit modules described herein are preferably copper films. The microstructure is arranged on the inner surface of the reflecting plate, and is used for reflecting the light emitting direction. The surface preferably refers to the bottom surface or the light emitting top surface of the optical plate.

Another preferred embodiment of the present invention further provides a backlight module, including an optical plate, a light emitting element and a lens body. The light emitting element is arranged on the surface of the optical plate, and the light emitting element has a light emitting direction. The light emitting direction forms an angle θ with the surface of the optical plate. The light-emitting element further includes a light-emitting body and an encapsulation material, and the encapsulation material covers the light-emitting body. The lens body is arranged on the surface and connected with the optical plate and the light emitting element. The lens body further includes a bevel. One end of the slope is connected to the light-emitting element, and the other end is connected to the optical plate. The luminous body is further adjacent to the optical plate and the lens body.

Through the above structure, the present invention is a light emitting diode (LED, Light Emitting Diode) to make the light guide plate structure light and thin backlight module and its light source structure, which can effectively reduce the thickness and weight of the light guide plate, and can The use efficiency of light energy is increased, and the convenience of assembly can also be improved, so it has the characteristics of easy construction; in addition, the light can be fully reflected in the light guide plate, which is convenient for use with light-emitting diodes.

Description of drawings

FIG. 1 is a schematic diagram of a light source structure of a known thin light guide plate;

2 is a top view of the backlight module and its light source structure of the present invention;

Fig. 3 is A-A sectional view of Fig. 2;

Fig. 4 is the schematic diagram of total reflection in the optical plate in the light incident direction of the present invention;

FIG. 5 is a schematic diagram of adding microstructures to increase light use efficiency in the present invention;

Fig. 6 is the comparative figure that the present invention carries out optical simulation experiment result to lens body;

Fig. 7a is a diagram of the first embodiment of the present invention setting the circuit module;

Fig. 7b is a diagram of a second embodiment of a circuit module provided by the present invention;

Fig. 7c is a diagram of a third embodiment of a circuit module provided in the present invention;

Fig. 7d is a diagram of a fourth embodiment of the present invention with a circuit module;

FIG. 8 is a diagram of another preferred embodiment of the backlight module and its light source structure of the present invention;

FIG. 9 is a schematic diagram of the backlight module and its light source structure combined frame of the present invention; and

FIG. 10 is a diagram of an embodiment of the backlight module and its light source structure combined with the frame of the present invention.

[Description of main component symbols]

100 light source structure 102 optical boards

104 surface 106 reflector

107 light top surface 108 bottom surface

110 light-emitting elements 112 light-emitting bodies

114 Packaging part 116 Light incident direction

120 lens body 122 bevel

130 circuit module 132 upper surface

134 side 136 lower surface

140 low refractive index layer 142 adhesive layer

150 frame 200 other optical boards

Detailed ways

The invention relates to a backlight module and a light source structure thereof with thinned optical boards and improved light energy utilization rate. In a preferred embodiment, the light emitting elements of the light source structure are light emitting diodes. In particular, the light-emitting diodes are preferably disposed in a manner of incident light at an angle inclined to the surface of the optical plate. In other words, the light emitting diodes are preferably disposed adjacent to the optical plate and the lens respectively. In addition, the additional lens body (lens) is preferably disposed between the optical plate and the light-emitting element by coating. However, in other different embodiments, the lens body can also be manufactured by computer numerical control (CNC) or other methods. Below promptly coordinate accompanying drawing, further illustrate each specific embodiment of the present invention and steps thereof:

As shown in FIG. 2 and FIG. 3 , the light source structure 100 in this embodiment includes an optical plate 102 , a light emitting element 110 and a lens body 120 . The light emitting element 110 is disposed on the surface 104 of the optical plate 102 . In the embodiment shown in FIG. 2 , preferably, a plurality of light emitting elements 110 are separately disposed on one end of the optical plate 102 . However, in other different embodiments, a single light emitting element 110 can also provide light. The optical plate 102 is preferably a light guide plate (LGP) or other transparent plates. The lens body 120 is disposed on the surface 104 and connected to the light emitting element 110 . In the embodiment shown in FIG. 3 , the light-emitting element 110 is preferably a light-emitting body 112 that emits light at an angle obliquely to the surface 104 of the optical plate 102 . The light emitting element 110 further includes an encapsulation portion 114 for encapsulating/encapsulating the light emitting body 112 . Thus, the light emitting element 110 has a light emitting direction 116 , so that the light enters the light at an angle θ with the surface 104 of the optical plate 102 . In addition, several other optical plates 200 are preferably disposed on the surface 104 of the optical plate 102 , such as elements such as diffusion sheets or rhombic sheets.

The lens body 120 preferably has a slope 122 . The slope 122 described here is preferably formed by surface tension when injecting/coating the lens body 120 . One end of the slope 122 is preferably connected to the light emitting element 110 , and the other end is connected to the optical board 102 . However, in other different embodiments, the lens body 120 can also be manufactured by computer numerical control or other methods. However, if the manufacture is controlled by computer numerical control, a high-transmittance adhesive material/layer must be provided between the optical plate 102 and the lens body 120 to increase the fixing force. In the embodiment shown in FIG. 3 , in order to avoid the loss of light efficiency, a lens body 120 structure with an inclined surface 122 is provided, which is mainly used to reflect the light of the illuminant 112 and make the light enter from the optical plate 102 at an angle. Light. In addition, injecting the structure of the lens body 120 can further improve the convenience of product assembly, avoiding the loss of light efficiency caused by misalignment or gaps between the optical plate 102 and the optical plate 102 due to assembly errors or slight tolerances. In particular, reflective materials can also be provided on the inclined surface 122 of the lens body 120 or on the two side surfaces not adjacent to the light emitting element 110 and the optical plate 102 to increase light use efficiency. In other words, when the light is reflected from the optical board 102 , it can be prevented from being emitted from the above position.

It should be noted here that the material of the encapsulation portion 114 can be resin or other transparent encapsulation materials. The material of the lens body 120 is also preferably resin or other high light-transmitting materials, which can be cured through thermal hardening, thermal plasticization, light hardening or room temperature hardening during processing.

As shown in FIG. 4 , the light source structure 100 preferably further includes a reflection plate 106 disposed on the bottom surface 108 of the optical plate 102 . There is a low refractive index layer 140 between the optical plate 102 and the reflection plate 106 . In the embodiment shown in FIG. 4 , the low refractive index layer 140 is preferably air or vacuum, and its refractive index is assumed to be n4=1. However, in other different embodiments, the low refractive index layer 140 can also be an adhesive material. In addition, in order to reduce the reflection energy loss caused by the light passing through two different media, or to minimize the reflection energy loss in the process of guiding the light into the optical plate 102, so as not to cause the light to exit the front end of the optical plate 102, it is assumed that the optical The refractive index of the plate 102 is n1, the refractive index of the lens body 120 is n2, and the refractive index of the light emitting element 110 is n3, then the refractive index n2 of the lens body 120 is preferably between the refractive index n1 of the optical plate 102 and the refractive index n3 of the light emitting element 110 , and the refractive index n1 of the optical plate 102 is preferably greater than or equal to the refractive index n3 of the light emitting element 110 . In other words, the refractive indices of the optical plate 102 , the lens body 120 and the light emitting element 110 must be quite close, ie n3≤n2≤n1.

Since the included angle θ is the included angle between the light emitting direction 116 and the surface 104 of the optical plate 102 , the sum of δ and θ is 90 degrees. In other words, θ+δ=90 degrees, if the incident light direction 116 is expected to form total reflection in the optical plate 102, according to Snall's law, δ≥sin ^-1 (n4/n1)(total critical reflection angle), it is known that the included angle θ is preferably less than or equal to sin ⁻¹ (n4/n1) (ie θ≤sin ⁻¹ (n4/n1)). In the embodiment shown in Figure 4, assuming that the refractive index n1 of the optical plate 102 is 1.48, and the low refractive index layer 140 is air (n4=1), it is confirmed by experimental results that when θ<48 degrees, δ> When the angle is 42 degrees, the light can be totally reflected in the optical plate 102 . However, when θ>48° and δ<42°, the light will emerge from the front of the optical plate 102 (as shown by the dotted line in FIG. 4 ). When the light cannot be transmitted to the other end (ie, the rear section) of the optical plate 102 through total reflection, it will affect the brightness and uniformity of the light source structure or the backlight module.

Although the illuminant 112 preferably enters light at an angle with the surface 104 of the optical plate 102 , it is inevitable that some light incident angles are not as expected. In other words, when the angle of the light incident direction 116 is too large, even perpendicular to the optical plate 102 , the light cannot be guided to the rear of the optical plate 102 . Therefore, as shown in FIG. 5 , the light source structure 100 preferably further includes several microstructures 170, which are respectively arranged on the inner surface of the reflection plate 106, for guiding or reflecting the aforementioned light to the rear of the optical plate 102. , that is, the other end of the light source structure 100, so as to improve the use efficiency of light energy. In the embodiment shown in FIG. 5 , the microstructure 170 is preferably a single dispersed triangular microstructure. However, in other different embodiments, it may also be triangular microstructures arranged continuously, or microstructures of polygonal, circular or other shapes.

As shown in FIG. 6 , regarding whether the lens body 120 is provided, or the influence of the ratio difference between the width a and the length b of the lens body 120 on the light efficiency, it can be known through optical experiment simulation. Obviously, the efficiency of guiding light into the optical plate 102 with or without the lens body 120 is better than that without the lens body 120 . Especially, when the aspect ratio (a:b) of the lens body 120 is 1:2, the highest light utilization efficiency can be obtained. In other words, when the lens body 120 is disposed or coated, the light can indeed be guided into the optical plate 102 .

As shown in FIGS. 7 a to 7 d , the light source structure 100 further includes a circuit module 130 . The circuit module 130 mentioned here especially refers to a flexible circuit board (FPC), a printed circuit board or a combination thereof. The circuit module 130 is coupled to the light emitting element 110 . Due to the design of different backlight modules and their light source structure 100, the circuit module 130 can be disposed on the upper surface 132 of the light emitting element 110, as shown in FIG. 7a. However, in the embodiment shown in FIG. 7 b , the circuit module 130 can also be disposed on the side surface 134 or the lower surface 136 of the light emitting element 110 (as shown in the embodiment of FIG. 7 c ). What's more, the circuit module 130 can also be replaced by copper film (Cu Foil) or copper wire, and the light emitting element 110 is soldered or positioned on it in other ways, as shown in FIG. 7d. In the embodiment shown in FIG. 7 d , the copper film or copper wire is preferably disposed between the light emitting element 110 and the surface 104 of the optical plate 102 . In addition, a material similar to the lens body 120 or an adhesive layer 142 is coated or disposed between the illuminant 112 and the optical plate 102 so as not to prevent light from the illuminant 112 from entering the optical plate 102 .

In the aforementioned embodiments, the light emitting element 110 is disposed on the surface 104 of the optical plate 102 . The aforementioned surface 104 refers to the light-emitting top surface 107 of the optical plate 102 . However, in the embodiment shown in FIG. 8 , the surface 104 on which the light emitting element 110 is disposed refers to the bottom surface 108 of the optical plate 102 . In addition, in this embodiment, the light-emitting top surface 107 of the optical plate 102 is preferably provided with a reflective plate 106 or other reflective materials for guiding light into the optical plate 102 . The rest of the structures are the same as those described above, and will not be repeated here.

As shown in FIG. 9 , the light source structure 100 further includes a frame 150 . The frame 150 is disposed on one end of the reflective plate 106 , and is positioned by bonding with the reflective plate 106 through the adhesive layer 142 . However, in the embodiment shown in FIG. 10 , the frame 150 can also be positioned or disposed on the optical plate 102 . If the frame 150 is fixed on the optical plate 102 , an adhesive layer 142 is preferably provided between the optical plate 102 and the reflection plate 106 . The adhesive layer 142 mentioned here must be a material with a low refractive index, such as silica gel, resin or other colloids. This facilitates the total reflection of the light in the optical plate 102 , reducing the energy loss caused by the light penetrating through the adhesive layer 142 and then reflected by the reflection plate 106 .

The present invention has been described by the above-mentioned related embodiments, however, the above-mentioned embodiments are only examples for implementing the present invention. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention. The modifications and equivalent arrangements made according to the spirit and principles of the present invention are included in the appended patent scope.

Claims (46)

1. A light source structure, characterized in that, comprising: an optical plate; A light-emitting element, disposed on a surface of the optical plate, the light-emitting element has a light emitting direction, and the light emitting direction forms an angle θ with the surface of the optical plate; and A lens body is arranged on the surface and connected with the light-emitting element, and the lens body includes a slope, one end of the slope is connected with the light-emitting element, and the other end is connected with the optical plate. 2. The light source structure according to claim 1, wherein the relationship between the refractive index n2 of the lens body and the refractive index n1 of the optical plate and the refractive index n3 of the light-emitting element satisfies: n1≥n2≥n3 . 3 . The light source structure according to claim 1 , wherein the light emitting element further comprises a luminous body and a packaging portion, and the packaging portion covers the luminous body. 4 . 4. The light source structure according to claim 3, wherein the illuminant is adjacent to the optical plate and the lens. 5. The light source structure according to claim 3, wherein the illuminant comprises a light emitting diode. 6. The light source structure according to claim 2, further comprising a reflective plate disposed on a bottom surface of the optical plate. 7. The light source structure according to claim 6, further comprising a low refractive index layer located between the optical plate and the reflector, the low refractive index layer has a refractive index n4, and the included angle θ≤sin ^-1 (n4/n1). 8. The light source structure according to claim 6, wherein the refractive index n1 of the optical plate is 1.48. 9. The light source structure according to claim 6, further comprising a frame, one side of the frame is disposed on the reflector, wherein the frame is bonded to the reflector by an adhesive layer. 10. The light source structure as claimed in claim 7, wherein the low refractive index layer further comprises an air medium. 11. The light source structure according to claim 6, further comprising at least one microstructure disposed on the reflector. 12. The light source structure according to claim 11, wherein the microstructure comprises a triangular microstructure. 13. The light source structure according to claim 1, wherein the included angle θ is smaller than 48 degrees. 14. The light source structure according to claim 1, wherein the surface is located on a bottom surface of the optical plate. 15. The light source structure according to claim 1, wherein the surface is located on a light emitting top surface of the optical plate. 16. The light source structure according to claim 1, further comprising a circuit module coupled to the light emitting element. 17. The light source structure according to claim 16, wherein the circuit module is disposed on an upper surface of the light emitting element and is disposed opposite to the optical plate. 18. The light source structure according to claim 16, wherein the circuit module is disposed on one side of the light-emitting element and opposite to the lens body. 19. The light source structure as claimed in claim 16, wherein the circuit module is disposed on the lower surface of the light emitting element and adjacent to the optical board. 20. The light source structure according to claim 16, wherein the circuit module is disposed between the light emitting element and the surface of the optical plate. 21. The light source structure as claimed in claim 16, wherein the circuit module comprises a copper film. 22. The light source structure according to claim 1, wherein the optical plate further comprises a light guide plate. 23. The light source structure according to claim 1, wherein the optical plate comprises a light-transmitting plate. 24. The light source structure according to claim 1, wherein the lens body material comprises resin. 25. A backlight module, characterized in that it comprises: an optical plate; A light emitting element is arranged on a surface of the optical plate, the light emitting element has a light emitting direction, and the light emitting direction forms an angle θ with the surface of the optical plate, wherein the light emitting element also includes a light emitting body and an encapsulation material, the encapsulation material wraps the luminous body; and A lens body, arranged on the surface and connected to the optical plate and the light-emitting element, the lens body includes a slope, one end of the slope is connected to the light-emitting element, and the other end is connected to the optical plate, wherein the light-emitting body and the light-emitting element The optical plate and the lens body are adjacent to each other. 26. The backlight module according to claim 25, wherein the relationship between the refractive index n2 of the lens body, the refractive index n1 of the optical plate, and the refractive index n3 of the light-emitting element satisfies: n1≥n2≥ n3. 27. The backlight module as claimed in claim 25, wherein the illuminant comprises a light emitting diode. 28. The backlight module as claimed in claim 26, further comprising a reflective plate, wherein the reflective plate is disposed on a bottom surface of the optical plate. 29. The backlight module according to claim 28, wherein there is a low refractive index layer between the optical plate and the reflector, the low refractive index layer has a refractive index n4, and the included angle θ≤sin ^-1 (n4/n1). 30. The backlight module as claimed in claim 28, further comprising a frame, the frame is disposed on one end of the reflective plate, and is bonded to the reflective plate through an adhesive layer. 31. The backlight module of claim 28, wherein the included angle θ is smaller than 48 degrees. 32. The backlight module as claimed in claim 29, wherein the low refractive index layer comprises an air medium. 33. The backlight module as claimed in claim 25, wherein the refractive index n1 of the optical plate is 1.48. 34. The backlight module of claim 28, further comprising at least one microstructure disposed on the reflective plate. 35. The backlight module as claimed in claim 34, wherein the microstructures comprise triangular microstructures. 36. The backlight module of claim 25, wherein the surface is located on a bottom surface of the optical board. 37. The backlight module of claim 25, wherein the surface is located on a light emitting top surface of the optical board. 38. The backlight module as claimed in claim 25, further comprising a circuit module coupled to the light emitting element. 39. The backlight module as claimed in claim 38, wherein the circuit module is disposed on an upper surface of the light-emitting element and opposite to the optical board. 40. The backlight module as claimed in claim 38, wherein the circuit module is disposed on one side of the light-emitting element and opposite to the lens body. 41. The backlight module as claimed in claim 38, wherein the circuit module is disposed on the lower surface of the light-emitting element and adjacent to the optical board. 42. The backlight module as claimed in claim 38, wherein the circuit module is disposed between the light emitting element and the surface of the optical plate. 43. The backlight module as claimed in claim 38, wherein the circuit module comprises a copper film. 44. The backlight module as claimed in claim 25, wherein the optical plate comprises a light guide plate. 45. The backlight module as claimed in claim 25, wherein the optical plate comprises a light-transmitting plate. 46. The backlight module as claimed in claim 25, wherein the lens material comprises resin.

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