CN112987391A

CN112987391A - Light source module and display device

Info

Publication number: CN112987391A
Application number: CN201911291210.XA
Authority: CN
Inventors: 林士逸; 杨文勋; 黄于铵
Original assignee: Coretronic Corp
Current assignee: Coretronic Corp
Priority date: 2019-12-16
Filing date: 2019-12-16
Publication date: 2021-06-18

Abstract

A light source module includes a substrate, a plurality of light-emitting elements, an encapsulation layer and a cover layer. The substrate has a bearing surface. The light-emitting element is disposed on the carrying surface of the substrate, wherein the light-emitting element has a light-emitting surface away from the carrying surface. The encapsulation layer covers the bearing surface and the light-emitting element, wherein the encapsulation layer has a first surface away from the bearing surface. The cover layer covers the first surface, wherein a second surface of the cover layer away from the first surface is provided with a plurality of pillar structures, and each of the pillar structures extends along an extension direction parallel to the second surface. Another display device is provided, including the above-mentioned light source module and a display panel. The display panel is arranged on the second surface of the cover layer and is opposite to the light source module. The light source module and the display device of the present invention are used to provide a surface light source with uniform brightness to improve display quality.

Description

Light source module and display device

[ technical field ] A method for producing a semiconductor device

The present invention relates to a light source module and a display device, and more particularly, to a light source module having a cylindrical structure on a light emitting surface of a cover layer and a display device having the same.

[ background of the invention ]

The structure of the liquid crystal display mainly comprises a backlight module, a display panel, an outer frame and other components. The backlight module is used for providing a surface light source for display of the display panel. The backlight module can be divided into an edge-type backlight module and a direct-type backlight module according to different light source directions. The direct type backlight module has the advantage of better uniformity of the surface light source, and is favorable for achieving the function of local dimming. Therefore, in the market, a direct type backlight module is mostly used in a large-medium-sized liquid crystal display using a Light Emitting Diode (LED) as a light source.

However, the direct type backlight module is limited by the factors such as size and power requirements, and the number and position of the light emitting elements of the direct type backlight module cannot be flexibly adjusted, so that the distance between the light emitting elements on the horizontal axis is different from the distance between the light emitting elements on the vertical axis, and thus, the surface light source provided by the direct type backlight module has a problem of uneven brightness.

This background section is provided merely to aid in understanding the present disclosure, and thus the disclosure in the background section may include art that does not constitute a part of the common general knowledge of those skilled in the art. Furthermore, the disclosure in the "background" does not represent a material or problem to be solved by one or more embodiments of the present invention, nor is it intended to be known or recognized by one of ordinary skill in the art prior to the filing of the present application.

[ summary of the invention ]

The invention provides a light source module which is used for providing a surface light source with uniform brightness.

The invention provides a display device for improving display quality.

Other objects and advantages of the present invention will be further understood from the technical features disclosed in the present invention.

To achieve one or a part of or all of the above or other objects, a light source module according to an embodiment of the invention includes a substrate, a plurality of light emitting elements, an encapsulation layer, and a cover layer. The substrate is provided with a bearing surface. The light emitting element is arranged on the bearing surface of the substrate, wherein the light emitting element is provided with a light emitting surface far away from the bearing surface. The packaging layer covers the bearing surface and the light-emitting element, wherein the packaging layer is provided with a first surface far away from the bearing surface. The covering layer covers the first surface, wherein a second surface of the covering layer, which is far away from the first surface, is provided with a plurality of column structures, and each of the column structures extends along an extending direction parallel to the second surface.

To achieve one or a part of or all of the above or other objects, a display device according to an embodiment of the invention includes the light source module and the display panel. The display panel is arranged on the second surface of the covering layer and is opposite to the light source module.

According to the light source module provided by the embodiment of the invention, the covering layer with the plurality of cylinder structures is arranged on the packaging layer, so that part of light rays emitted from the packaging layer originally are totally reflected between the covering layer and an air interface, and the light source module is beneficial to transmitting part of light rays farther in the light source module and then emitting the light rays, further the emitting position of the light rays from the light source module is changed, and the cylinder structures have different emitting effects on the light rays in different directions. Therefore, the light source module of the embodiment of the invention can provide a surface light source with uniform brightness without increasing the number of the light emitting elements. The display device of the embodiment of the invention has good display quality due to the adoption of the light source module.

In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

[ description of the drawings ]

Fig. 1 is a schematic perspective view of a light source module according to an embodiment of the invention.

Fig. 2 is a schematic top view of the substrate and the light emitting device in fig. 1.

Fig. 3A is a partial cross-sectional view taken along line a-a of fig. 1.

Fig. 3B is a schematic sectional view taken along line B-B of fig. 1.

Fig. 4A is a partial cross-sectional view of a light source module according to another embodiment of the invention.

Fig. 4B is a partial cross-sectional view of a light source module according to another embodiment of the invention.

Fig. 5 is a schematic perspective view of a light source module according to another embodiment of the invention.

Fig. 6 is a schematic diagram of a display device according to an embodiment of the present invention.

[ detailed description ] embodiments

The foregoing and other technical and other features and advantages of the invention will be apparent from the following detailed description of a preferred embodiment, taken in conjunction with the accompanying drawings. Directional terms as referred to in the following examples, for example: up, down, left, right, front or rear, etc., are simply directions with reference to the drawings. Accordingly, the directional terminology is used for purposes of illustration and is in no way limiting.

Fig. 1 is a schematic perspective view of a light source module according to an embodiment of the invention, and fig. 2 is a schematic top view of the substrate and the light emitting device in fig. 1. Referring to fig. 1 and fig. 2, a light source module 10 of the present embodiment includes a substrate 11, a plurality of light emitting elements 12, an encapsulation layer 13, and a cover layer 14. The substrate 11 has a carrying surface 110. The light emitting element 12 is disposed on the carrying surface 110 of the substrate 11, and the light emitting element 12 has a light emitting surface 120 far away from the carrying surface 110. The encapsulant layer 13 covers the carrier surface 110 and the light emitting device 12, and the encapsulant layer 13 has a first surface 130 far away from the carrier surface 110. In one embodiment, the encapsulation layer 13 covers the light emitting device 12 by directly contacting the surfaces of the light emitting device 12 exposed on the carrying surface 110, so as to prevent the light emitting device 12 from being deteriorated by air and moisture due to gaps. The covering layer 14 covers the first surface 130, wherein a second surface 140 of the covering layer 14 away from the first surface 130 is provided with a plurality of pillar structures 141, and each of the pillar structures 141 extends along an extending direction E parallel to the second surface 140. In one embodiment, the covering layer 14 covers the first surface 130 in a manner of directly contacting the first surface 130.

The substrate 11 may be a circuit board, and the carrying surface 110 may be a surface of the substrate 11 on which a plurality of conductive patterns (not shown) are disposed, and the conductive patterns are used for electrically connecting the light emitting elements 12. For example, when the substrate 11 is a Printed Circuit Board (PCB), the conductive patterns may be metal lines on the PCB, but the invention is not limited thereto. In addition, the light source module 10 further includes a light reflecting layer (not shown) disposed on the supporting surface 110 where the light emitting device 12 is not disposed. The light reflecting layer can reflect the light incident on the carrying surface 110 into the packaging layer 13, so as to improve the light utilization rate.

The light emitting element 12 may be a light emitting diode, or may be another type of light emitting element. In addition, the light emitting device 12 can be an unpackaged light emitting chip, such as a light emitting diode chip, directly cut from a wafer. For example, the led chip is a die-level nitride led chip emitting blue light with dominant wavelength, but the invention is not limited thereto.

The encapsulating layer 13 is, for example, a light-transmitting layer. In one embodiment, the refractive index of the encapsulation layer 13 is about 1.40-1.59, such as 1.41. For example, the material of the encapsulation layer 13 may be selected from Silicone resin (Silicone), Epoxy resin (Epoxy), ultraviolet curable resin, or other materials that can be used to encapsulate the light emitting element 12.

The cover layer 14 is, for example, a light-transmitting layer. In one embodiment, the index of refraction of the cover layer 14 is less than the encapsulant layer 13. In detail, the refractive index of the covering layer 14 may be between 1.2 and 1.3, for example, 1.3. For example, the material of the cover layer 14 may be selected from silicone resin, epoxy resin, ultraviolet curing resin, or other materials that can be used to encapsulate the light emitting element 12.

The pillar structure 141 and the covering layer 14 may be integrally formed, for example, by injection molding to form the pillar structure 141 and the covering layer 14 simultaneously. In addition, the column structure 141 can also be a prism sheet disposed on the second surface 140, for example, the prism sheet is attached on the second surface 140 of the cover layer 14. The pillar structure 141 has a top 141a and a side 141b, and the shape of the pillar structure 141 may be a corner pillar structure with the side 141b being a slope and the top 141a being a pointed top, but the invention is not limited thereto.

In the present embodiment, the light emitting elements 12 are arranged in an array along a first direction X and a second direction Y perpendicular to each other, for example. The light emitting elements 12 are arranged at intervals in the first direction X at a first pitch D1, and arranged at intervals in the second direction Y at a second pitch D2. The second spacing D2 is, for example, greater than the first spacing D1. The extending direction E is, for example, parallel to the second direction Y. For example, when the light source module 10 is disposed in a rectangular display panel (e.g., a display panel with an aspect ratio of 4: 3 or 16: 9), the light emitting elements 12 are arranged at different intervals in the first direction X and the second direction Y, respectively, according to the size of the display panel. Generally, since the light emitting angles of the light emitting elements 12 in the first direction X and the second direction Y are the same, if the light emitting angles of the light emitting elements 12 are suitable for the first distance D1, the light emitting elements 12 can uniformly emit light in the first direction X, but in the second direction Y, because the second distance D2 between the light emitting elements 12 is large, a dark region is easily formed between two adjacent light emitting elements 12. In order to improve this situation, the light source module 10 of the present embodiment adds the cover layer 14 on the package layer 13 to adjust the transmission paths of the light emitting element 12 in the first direction X and the second direction Y. See description below for details.

Fig. 3A is a partial cross-sectional view taken along line a-a of fig. 1. Referring to fig. 3A, as mentioned above, when the cover layer 14 is not added, there is a dark area W between two adjacent light-emitting elements 12. In the embodiment, due to the arrangement of the cover layer 14, a part of the light ray with a larger light-emitting angle (for example, the light ray L1) is totally reflected by the first surface 130, then reflected to the first surface 130 of the package layer 13 through the carrying surface 110, enters the cover layer 14 from the first surface 130, and then exits from the cover layer 14. In other words, the light L1 can be totally reflected at the first surface 130 due to the cover layer 14. Although not shown, since the refractive index of the encapsulation layer 13 is greater than that of the cover layer 14, the angle of refraction of the light L1 entering the cover layer 14 is greater than the angle of incidence, and thus the light L passes further in the second direction Y, and exits from the dark area W. On the other hand, after a part of the light (e.g., the light L2) with a smaller light-emitting angle provided by the light emitting device 12 enters the cover layer 14 from the encapsulant layer 13, since the traveling direction of the light L2 transmitted is the same as or substantially the same as the extending direction E of the pillar structure 141, and since the refractive index of the pillar structure 141 is greater than that of air, the light L2 will be totally reflected back to the encapsulant layer 13 at the interface between the pillar structure 141 and air, and then reflected by the supporting surface 110 to sequentially pass through the encapsulant layer 13 and the cover layer 14, and then exit from the dark area W. Although not shown, since the refractive index of the encapsulation layer 13 is greater than that of the cover layer 14, the refraction angle of the light L2 entering the cover layer 14 from the encapsulation layer 13 is greater than the incident angle, which also helps the light L2 to transmit further. Based on the above, since the cover layer 14 is disposed to enable more light to exit from the dark area W, the problem of insufficient brightness of the dark area W can be solved, and the uniformity of the surface light source provided by the light source module 10 can be improved.

Fig. 3B is a schematic sectional view taken along line B-B of fig. 1. Referring to fig. 3B, after the light L3 emitted from the light emitting device 12 enters the cover layer 14 from the encapsulation layer 13 in the first direction X, the light L3 can directly exit from the side 141B of the pillar structure 141 because the incident angle when the light L enters the side 141B of the pillar structure 141 is smaller, and the light L will not be totally reflected at the interface between the pillar structure 141 and the air and will not be further transmitted in the first direction X as shown in fig. 3A. That is, the arrangement of the covering layer 14 and the pillar structure 141 does not greatly affect the light emitting of the light L3 in the first direction X, so that the uniformity of the surface light source in the first direction X can be maintained.

In this embodiment, the light source module 10 may further include an optical film (not shown) disposed at a side adjacent to the pillar structure 141. The number of the optical films may be one or more, and the optical films may be a diffusion sheet, a prism sheet, a wavelength conversion sheet, etc., but the present invention is not limited thereto.

Fig. 4A is a partial cross-sectional view of a light source module according to another embodiment of the invention. Referring to fig. 4A, a light source module 10b of the present embodiment is similar to the light source module 10 described above, and the main difference is that the light source module 10b of the present embodiment further includes an optical element with a reflection function. In detail, the light source module 10b further includes a plurality of reflective elements 16 disposed above the supporting surface 110 and respectively opposite to the light emitting surface 120. Specifically, the reflective elements 16 are disposed on the light emitting surfaces 120 of the light emitting elements 12, respectively, and the encapsulation layer 13 covers the reflective elements 16 and the light emitting elements 12. In one embodiment, the encapsulation layer 13 covers the reflective element 16 and the light emitting element 12 by directly contacting the exposed surfaces of the reflective element 16 and the light emitting element 12. In the present embodiment, the reflective element 16 can reflect part of the light and transmit part of the light, for example, but not limited to, the reflective element 16 can be a Distributed Bragg Reflector (DBR). The light pattern provided by the light emitting element 12 through the reflecting element 16 is a light beam with a central area having a lower brightness than the surrounding area, and resembles a bat wing, so that the bright area above the light emitting element 12 can be suppressed, and the brightness of the surrounding area can be improved, thereby further improving the uniformity of the surface light source.

Fig. 4B is a partial cross-sectional view of a light source module according to another embodiment of the invention. Referring to fig. 4B, a light source module 10c of the present embodiment is similar to the light source module 10, and the main difference is that in the light source module 10c of the present embodiment, a first surface 130c of an encapsulation layer 13c has a plurality of reflective grooves 131 respectively corresponding to the light emitting elements 12, and reflective materials 17 are respectively disposed in the reflective grooves 131. In detail, the reflective cavities 131 respectively form reflective cavity openings 131a on the first surface 130c, and the areas of the reflective cavity openings 131a are respectively larger than the area of the light emitting surface 120 of the light emitting element 12. The shape of the reflective cavities 131 is, for example, pyramid, prism, step, hemisphere, semi-ellipsoid, parabolic, or polygon, but the invention is not limited thereto. In the present embodiment, the covering layer 140 covers and directly contacts the reflective material 17 of the reflective trough 131 in addition to the first surface 130 c. In another embodiment, the covering layer 140 covers and directly contacts only the first surface 130c, and has a gap with the reflective material 17 of the reflective groove 131. In one embodiment, the covering layer 14 of the light source module 10a is opened with holes (not shown) at positions corresponding to the reflective troughs 131 to expose the reflective troughs 131, and the top view of the covering layer 14 is shown as being in a grid or checkerboard shape and correspondingly surrounding the light emitting elements 12 and the reflective troughs 131. In another embodiment, the covering layer 14 can be omitted directly, and a pillar structure (not shown) can be formed on the first surface 130c outside the reflective trench 131.

It should be noted that in the embodiment of fig. 4B, the pillar structures 141 can also be directly disposed on the first surface 130c where the reflective grooves 131 are not disposed. In short, the covering layer 14 may include only the pillar structures 141, and the pillar structures 141 on the first surface 130c are shown as being in a grid or a checkerboard shape, and correspondingly surround the reflective slot openings 131a, such that the reflective slot openings 131a are exposed between the pillar structures 141. Since the features of the pillar structure 141 have been described in detail in the foregoing, other details are not repeated here.

The reflective material 17 is used to reflect the light incident on the reflective groove 131 to suppress the bright area above the light emitting device 12, and further improve the uniformity of the surface light source. On the other hand, the reflective material 17 may cover the bottom 141c of the reflective groove 131 and not fill the reflective groove 131. The reflective material 17 may include an optical material such as a reflective material, a light diffusing material, or a wavelength conversion material, but the present invention is not limited thereto.

Fig. 5 is a schematic perspective view of a light source module according to another embodiment of the invention. Referring to fig. 5, a light source module 10d of the present embodiment is similar to the light source module 10, and the main difference is that in the light source module 10d of the present embodiment, the light emitting elements 12 are arranged in an array along a first direction X and a second direction Y perpendicular to each other, and an extending direction E' of the pillar structure 141d of the covering layer 14d is not parallel to the first direction X and the second direction Y. For example, the extending direction E' may be located between the first direction X and the second direction Y, and may be included at an angle of about 40 ° to 50 ° (preferably 45 °) with respect to the positive second direction Y. Since the light source module 10d of the present embodiment can adjust the light emitting positions of the light emitting elements 12 in different directions, the uniformity of the surface light source can also be improved.

Fig. 6 is a schematic diagram of a display device according to an embodiment of the present invention. Referring to fig. 6, the display device 20 includes the

light source module

10, 10b, 10c or 10d and the display panel 21 of any of the foregoing embodiments, and related descriptions will be omitted herein.

The display panel 21 is disposed on the second surface 140 of the covering layer 14 and is opposite to the light source module 10. The display panel 21 is, for example, a liquid crystal display panel or other types of display panels, and the light source module 10 is used for providing light to the display panel 21. Since the display device 20 can be disposed in cooperation with the

light source module

10, 10b, 10c, or 10d, it can provide good image quality.

In summary, in the light source module of the embodiment of the invention, the cover layer having the plurality of pillar structures is disposed on the encapsulation layer, so that a part of the light can be totally reflected between the encapsulation layer and the cover layer, and the emergent position from the encapsulation layer is changed, and the pillar structures have different emergent effects on the light in different directions. Therefore, the light source module of the embodiment of the invention can provide a surface light source with uniform brightness without increasing the number of the light emitting elements. The display device of the embodiment of the invention has good display quality due to the adoption of the light source module.

It should be understood that the above description is only a preferred embodiment of the present invention, and that the scope of the present invention should not be limited thereby, and that the appended claims and the description of the invention should be construed as broadly as the present invention includes all the equivalent variations and modifications which fall within the true scope and spirit of the invention. Moreover, not all objects or advantages or features disclosed herein are necessarily achieved by any one embodiment or claim of the invention. In addition, the abstract and the title of the invention are provided for assisting the search of patent documents and are not intended to limit the scope of the invention. Furthermore, the terms "first," "second," and the like in the description or in the claims are used only for naming elements (elements) or distinguishing different embodiments or ranges, and are not used for limiting the upper limit or the lower limit on the number of elements.

Claims

1. A light source module, characterized in that the light source module comprises a substrate, a plurality of light-emitting elements, an encapsulation layer and a cover layer, wherein,

the substrate has a bearing surface;

The plurality of light-emitting elements are disposed on the carrying surface of the substrate, wherein each of the plurality of light-emitting elements has a light-emitting surface away from the carrying surface;

the encapsulation layer covers the carrying surface and the plurality of light emitting elements, wherein the encapsulation layer has a first surface away from the carrying surface; and

The cover layer covers the first surface, wherein a second surface of the cover layer away from the first surface is provided with a plurality of columnar structures, each of the plurality of columnar structures along a direction parallel to the The extension direction of the second surface extends.

2 . The light source module according to claim 1 , wherein the light source module further comprises a plurality of reflective elements, and the plurality of reflective elements are arranged above the bearing surface and are respectively opposite to the plurality of light emitting surfaces. 3 . .

3 . The light source module according to claim 1 , wherein the plurality of light-emitting elements are arranged in an array along a first direction and a second direction perpendicular to each other, and the plurality of light-emitting elements are arranged in the first direction. 4 . They are arranged at intervals with a first pitch, and are arranged at intervals in the second direction with a second pitch, the second pitch is greater than the first pitch, and the extending direction is parallel to the second direction.

4 . The light source module according to claim 1 , wherein the plurality of light-emitting elements are arranged in an array along a first direction and a second direction that are perpendicular to each other, and the extending direction is not parallel to the first direction. 5 . with the second direction.

5 . The light source module according to claim 1 , wherein the plurality of column structures and the cover layer are integrally formed. 6 .

6 . The light source module according to claim 1 , wherein the plurality of column structures are prism sheets disposed on the second surface. 7 .

7 . The light source module according to claim 1 , wherein the refractive index of the cover layer is smaller than the refractive index of the encapsulation layer. 8 .

8 . The light source module according to claim 2 , wherein the plurality of reflection elements are respectively disposed on the plurality of light-emitting surfaces, and the encapsulation layer covers the plurality of reflection elements. 9 .

9 . The light source module according to claim 1 , wherein the first surface has a plurality of reflective grooves corresponding to the plurality of light-emitting elements, and reflective materials are respectively provided in the plurality of reflective grooves. 10 .

10 . The light source module according to claim 9 , wherein the plurality of reflection grooves respectively form reflection groove openings on the first surface, and the areas of the plurality of reflection groove openings are respectively larger than those of the plurality of reflection grooves. 11 . areas of the plurality of light-emitting surfaces of the light-emitting element.

11. A display device, characterized in that the display device comprises a light source module and a display panel, wherein,

The light source module includes a substrate, a plurality of light-emitting elements, a plurality of reflective elements, an encapsulation layer and a cover layer, wherein,

the substrate has a bearing surface;

The plurality of reflective elements are disposed above the bearing surface and are respectively opposite to the plurality of light emitting surfaces;

The cover layer covers the first surface, wherein a second surface of the cover layer away from the first surface is provided with a plurality of columnar structures, each of the plurality of columnar structures along a direction parallel to the the extension direction of the second surface extends; and

The display panel is disposed on the second surface of the cover layer and is opposite to the light source module.

12 . The display device according to claim 11 , wherein the light source module further comprises a plurality of reflective elements, and the plurality of reflective elements are disposed above the bearing surface and are respectively opposite to the plurality of light-emitting surfaces. 13 . .

13. The display device according to claim 11, wherein the plurality of light emitting elements are arranged in an array along a first direction and a second direction perpendicular to each other, and the plurality of light emitting elements are arranged in the first direction They are arranged at intervals with a first pitch, and are arranged at intervals in the second direction with a second pitch, the second pitch is greater than the first pitch, and the extending direction is parallel to the second direction.

14. The display device according to claim 11, wherein the plurality of light emitting elements are arranged in an array along a first direction and a second direction perpendicular to each other, and the extending direction is not parallel to the first direction with the second direction.

15 . The display device according to claim 11 , wherein the plurality of column structures and the cover layer are integrally formed. 16 .

16 . The display device of claim 11 , wherein the plurality of pillar structures are prism sheets disposed on the second surface. 17 .

17. The display device of claim 11, wherein a refractive index of the cover layer is smaller than a refractive index of the encapsulation layer.

18 . The display device of claim 12 , wherein the plurality of reflective elements are respectively disposed on the plurality of light-emitting surfaces, and the encapsulation layer covers the plurality of reflective elements. 19 .

19 . The display device according to claim 11 , wherein the first surface has a plurality of reflective grooves corresponding to the plurality of light-emitting elements respectively, and reflective materials are respectively provided in the plurality of reflective grooves. 20 .

20 . The display device according to claim 19 , wherein the plurality of reflection grooves respectively form a reflection groove opening on the first surface, and the areas of the plurality of reflection groove openings are respectively larger than those of the plurality of reflection grooves. 21 . areas of the plurality of light-emitting surfaces of each light-emitting element.