TWI795162B - Light emitting device - Google Patents

Abstract

A light emitting device includes a secondary lens, a substrate, a light emitting unit and a shading layer. The secondary lens includes a light emitting surface and a bottom surface opposite to the light emitting surface. The light emitting surface and the bottom surface define a first thickness therebetween. The secondary lens has a through hole. The through hole communicates with the light emitting surface and the bottom surface. The substrate is disposed on the bottom surface and covers the through hole. The light emitting unit is disposed on the substrate and is at least partially located inside the through hole. The shading layer is disposed on the light emitting surface and covers the through hole. A shortest vertical distance of the shading layer relative to the bottom surface is equal to the first thickness.

Description

Light emitting element

The invention relates to a light emitting element.

In the existing flat panel display device, the liquid crystal module needs to cooperate with the surface light source provided by the backlight module so that the liquid crystal display device can display clear images. Basically, the existing backlight modules can be divided into two types: edge-lite and direct. Among them, the direct-lit backlight module provides a more uniform surface light source brightness and can provide area lighting. function, so it has been widely used in household and commercial display devices. Moreover, mid-to-high-end liquid crystal display devices with local dimming technology have been widely used recently. This mid-to-high-end liquid crystal display device can improve the image contrast to that close to that of organic light-emitting diode display devices, which is the current development of liquid crystal display devices. one of the trends.

However, in the above-mentioned direct-lit backlight module used in the liquid crystal display device, light-emitting elements such as light-emitting diodes (Light-Emitting Diode, LED) need to be distributed behind the liquid crystal panel. The direct-lit backlight module in the prior art also arranges a lens between the light-emitting diode and the liquid crystal panel, and also requires an additional light mixing space, so it is difficult to reduce the size of the display device. In other words, due to the longer optical distance (Optical Distance, OD) required by the direct-lit backlight module, and the volume of the light-emitting element itself and the lens, the thickness of the display device cannot be reduced. Therefore, how to further maintain the uniformity of the surface light source and reduce the thickness of the display device is undoubtedly an important issue that the industry pays close attention to.

One of the objectives of the present invention is to provide a light-emitting element that provides good uniformity in brightness.

According to an embodiment of the present invention, a light emitting element includes a secondary lens, a substrate, a light emitting unit, and a light shielding layer. The secondary lens includes an opposite light-emitting surface and a bottom surface, a first thickness is defined between the light-emitting surface and the bottom surface, the secondary lens has a perforation, and the perforation connects the light-emitting surface and the bottom surface. The substrate is arranged on the bottom surface and covers the through hole. The light emitting unit is disposed on the substrate and at least partially located in the through hole. The light-shielding layer is arranged on the light-emitting surface and covers the perforation, and the shortest vertical distance between the light-shielding layer and the bottom surface is the same as the first thickness.

In one or more embodiments of the present invention, the above-mentioned light-emitting unit has a certain height, which is less than 1.5 times the first thickness and greater than 50 microns.

In one or more embodiments of the present invention, the above-mentioned light-shielding layer has a second thickness, and the second thickness is constant.

In one or more embodiments of the present invention, the above-mentioned light-emitting unit includes a light-emitting chip and encapsulant. The light emitting chip is arranged on the substrate. The encapsulation adhesive covers the light-emitting chip and is at least partially located between the light-emitting chip and the light-shielding layer, and the light-emitting chip is at least partially located between the encapsulation adhesive and the substrate.

In one or more embodiments of the present invention, the above-mentioned light emitting unit and the secondary lens are separated from each other.

In one or more embodiments of the present invention, the above-mentioned encapsulant has a first width, the secondary lens has a second width, and the ratio of the second width to the first width ranges from 5 times to 10 times.

In one or more embodiments of the present invention, the above-mentioned light-shielding layer is made of soft material.

In one or more embodiments of the present invention, the above-mentioned secondary lens includes a lens body and a reflective layer. The light emitting surface is located on the lens body. The reflection layer is arranged on the side of the lens body away from the light-emitting surface, and the bottom surface is located on the side of the reflection layer away from the lens body.

In one or more embodiments of the present invention, the aforementioned reflective layer is a reflective coating.

In one or more embodiments of the present invention, the above-mentioned reflective layer is a reflective sheet structure.

The foregoing embodiments of the present invention have at least the following advantages:

(1) Since the light-emitting element only includes a single layer of light-shielding layer, and the second thickness of the light-shielding layer is constant, by simply and easily setting the transmittance of the light-shielding layer, the user can accurately control the light-emitting element to pass through the light-shielding layer The brightness of the light emitted by the layer is beneficial to make the brightness provided by the light-emitting element have good uniformity.

(2) Since the light-shielding layer is not located in the perforation of the secondary lens, and the light-shielding layer only needs to be placed on the light-emitting surface of the secondary lens, the manufacturing process of the light-emitting element is simple and easy, which is beneficial to reduce the production cost, and can also effectively improve the light emission. component yield.

(3) Since the ratio of the second width of the secondary lens to the first width of the light-emitting unit is between 5 times and 10 times, the brightness provided by the light-emitting element from the light-emitting surface has good uniformity.

Several embodiments of the present invention will be disclosed in the following figures. For the sake of clarity, many practical details will be described together in the following description. It should be understood, however, that these practical details should not be used to limit the invention. That is, in some embodiments of the present invention, these practical details are unnecessary. In addition, for the sake of simplifying the drawings, some commonly used structures and elements will be shown in a simple schematic way in the drawings, and in all the drawings, the same reference numerals will be used to represent the same or similar elements . And if possible in practice, the features of different embodiments can be used interchangeably.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have their ordinary meanings that can be understood by those skilled in the art. Furthermore, the definitions of the above-mentioned words in the commonly used dictionaries should be interpreted in the content of this specification as meanings consistent with the relevant fields of the present invention. Unless specifically defined, these terms are not to be interpreted in an idealized or overly formal sense.

Please refer to Figures 1 and 2. FIG. 1 is a schematic perspective view showing a light emitting device 100 according to an embodiment of the present invention. FIG. 2 is a partially enlarged schematic diagram showing the area A in FIG. 1 , where the light-shielding layer 140 is omitted. In this embodiment, as shown in FIGS. 1 to 2 , the light emitting element 100 includes a secondary lens 110 , a light emitting unit 130 , and a light shielding layer 140 . The secondary lens 110 includes a light-emitting surface 111 , and the secondary lens 110 has a perforation P, and the perforation P communicates with the light-emitting surface 111 . The light emitting unit 130 is at least partly located in the perforation P of the secondary lens 110 , and the light-shielding layer 140 can be made of soft material or hard material according to the actual situation, and is disposed on the light-emitting surface 111 of the secondary lens 110 and covers the perforation P.

Specifically, as shown in FIG. 2 , the secondary lens 110 includes an inner surface 113 , the inner surface 113 is adjacent to the light-emitting surface 111 , and defines a through hole P around it. According to actual conditions, the inner surface 113 of the secondary lens 110 can be a smooth surface, a rough surface or a surface with microstructures. When the light-emitting element 100 is in operation, the light-emitting unit 130 emits light toward the inner surface 113 of the secondary lens 110 and the light-shielding layer 140 (see FIGS. 1 , 3-4 ). The light emitted toward the inner surface 113 enters the secondary lens 110 through the inner surface 113 . Except for part of the light emitted towards the light shielding layer 140 passing through the light shielding layer 140 , the rest is reflected by the light shielding layer 140 , and then enters into the secondary lens 110 through the inner surface 113 . Furthermore, the light entering the secondary lens 110 will pass through the light-emitting surface 111 and exit the secondary lens 110 .

Please refer to Figures 3 and 4. Fig. 3 is a schematic cross-sectional view along line B-B in Fig. 1 . FIG. 4 is a partially enlarged schematic diagram showing the area C in FIG. 3 . In this embodiment, as shown in Figures 3 to 4, the secondary lens 110 further includes a bottom surface 112, the bottom surface 112 is opposite to the light-emitting surface 111, and a first thickness TK1 is defined between the light-emitting surface 111 and the bottom surface 112, that is, two The thickness of the secondary lens 110. Moreover, the light-emitting element 100 further includes a substrate 120, the substrate 120 is disposed on the bottom surface 112 of the secondary lens 110 and covers the perforation P, that is, the perforation P is located between the light shielding layer 140, the inner surface 113 of the secondary lens 110 and the substrate 120, The light emitting unit 130 is disposed on the substrate 120 and located in the through hole P. As shown in FIG. It should be noted that the shortest vertical distance DS of the light shielding layer 140 relative to the bottom surface 112 is the same as the first thickness TK1 of the secondary lens 110 . In other words, in this embodiment, the side of the light-shielding layer 140 facing the secondary lens 110 is coplanar with the light-emitting surface 111 of the secondary lens 110 , that is, the light-shielding layer 140 is located outside the perforation P of the secondary lens 110 but not outside the perforation P. Inside P.

In this embodiment, as shown in FIG. 4 , the light emitting unit 130 has a height H, and the height H of the light emitting unit 130 is greater than 50 micrometers. Furthermore, for example, as shown in FIG. 4, the height H of the light-emitting unit 130 is smaller than the first thickness TK1 between the light-emitting surface 111 and the bottom surface 112, so the light-emitting unit 130 and the light-shielding layer 140 are separated from each other, that is, the light-emitting unit 130 does not touch the light-shielding layer 140 . In other embodiments, the height H of the light emitting unit 130 may be the same as the first thickness TK1 between the light emitting surface 111 and the bottom surface 112 , so that the light emitting unit 130 and the light shielding layer 140 are in contact with each other. Furthermore, as shown in FIG. 4 , the light emitting unit 130 is separated from the inner surface 113 of the secondary lens 110 , that is, the light emitting unit 130 does not contact the secondary lens 110 .

Since the light-shielding layer 140 is not located in the perforation P of the secondary lens 110, and the light-shielding layer 140 only needs to be disposed on the light-emitting surface 111 of the secondary lens 110, the manufacturing process of the light-emitting element 100 is simple and easy, which is beneficial to reduce the production cost, and also The yield rate of the light emitting element 100 can be effectively improved.

In addition, as shown in FIG. 4 , the light shielding layer 140 has a second thickness TK2. In this embodiment, the second thickness TK2 is constant, that is, the second thickness TK2 of the light shielding layer 140 does not change and has a single value. Since the light-emitting element 100 only includes a single layer of light-shielding layer 140, and the second thickness TK2 of the light-shielding layer 140 is constant, the user can accurately control the light-emitting element by simply and easily setting the transmittance of the light-shielding layer 140. The brightness of the light emitted by the 100 through the light-shielding layer 140 is beneficial to make the brightness provided by the light-emitting element 100 have good uniformity. For example, the transmittance range of the light shielding layer 140 is between 20% and 80%, preferably between 40% and 55%, but the present invention is not limited thereto.

On the other hand, for example, as shown in FIG. 2 , the light emitting unit 130 has a shape of a square cylinder. In other embodiments, according to actual conditions, the shape of the light emitting unit 130 may be a cylinder or other polygonal prisms.

Furthermore, in this embodiment, as shown in FIGS. 1 , 3 and 4 , the secondary lens 110 includes a lens body 114 and a reflective layer 115 . The light emitting surface 111 is located on the lens body 114 , the reflective layer 115 is disposed on a side of the lens body 114 away from the light emitting surface 111 , and the bottom surface 112 is located on a side of the reflective layer 115 away from the lens main body 114 . In practical applications, the reflective layer 115 can be a reflective coating or a reflective sheet structure, and the light reflection method of the reflective layer 115 can be specular reflection or diffuse reflection.

In addition, in practical application, the material of the lens body 114 includes, for example, polycarbonate (PC) or poly(methyl methacrylate), PMMA), but the present invention is not limited thereto. In other implementations, according to actual conditions, the material of the lens body 114 may include other transparent materials.

Specifically, as shown in FIG. 3 , when the light-emitting element 100 operates, the light-emitting unit 130 emits light L1 toward the inner surface 113 , and the light L1 enters the lens body 114 of the secondary lens 110 through the inner surface 113 . At the same time, the light emitting unit 130 emits light L2 toward the light-shielding layer 140, part of the light L2 will pass through the light-shielding layer 140 to become light L3, and the rest of the light L2 will be reflected by the light-shielding layer 140 to become light L4, and the light L4 will then pass through The inner surface 113 enters into the lens body 114 of the secondary lens 110 . The light L1 and light L4 entering the lens main body 114 will be reflected by the reflective layer 115 and the light-emitting surface 111 (when the incident angles of the light rays L1 and L4 relative to the light-emitting surface 111 are relatively large) and transmitted in the lens main body 114, and finally The light is emitted from the light emitting surface 111 of the secondary lens 110 to become light L5. It should be understood that the position where light L5 emerges from the light-emitting surface 111 may be far away from the inner surface 113 of the secondary lens 110 , so the brightness provided by the light-emitting element 100 from the light-emitting surface 111 has good uniformity. Moreover, in this embodiment, since the light-emitting element 100 only includes a single layer of light-shielding layer 140, the user can simply and easily adjust the transmittance of the light-shielding layer 140 to make the brightness of light L3 and light L5 similar. Further, the brightness provided by the light emitting element 100 has good uniformity.

In practical applications, in order to improve the light emitting effect of the light L5 emitted from the light emitting surface 111 , the light emitting surface 111 of the secondary lens 110 may be a rough surface or a surface with microstructures. For example, the microstructure on the light-emitting surface 111 can be a concentric concavo-convex structure surrounding the perforation P, irregularly distributed laser dots, regularly distributed laser dots, or microstructures arranged along a certain direction, but this The invention is not limited thereto.

Further, as shown in FIG. 3 , the light emitting unit 130 has a first width W1, and the secondary lens 110 has a second width W2. As mentioned above, since the position where light L5 emerges from the light-emitting surface 111 can be far away from the inner surface 113 of the secondary lens 110, so that the brightness provided by the light-emitting element 100 from the light-emitting surface 111 has good uniformity, preferably, the secondary lens The ratio of the second width W2 of 110 to the first width W1 of the light emitting unit 130 ranges from 5 times to 10 times. For example, the ratio range of the second width W2 of the secondary lens 110 to the first width W1 of the light emitting unit 130 may be 5 times, 6 times, 7 times, 8 times, 9 times or 10 times. For example, when the shape of the light emitting unit 130 is a rectangular cylinder, the maximum width of the light emitting unit 130 is regarded as the first width W1.

Please refer to Figure 5. FIG. 5 is a partially enlarged schematic diagram illustrating a light emitting device 100 according to another embodiment of the present invention. In this embodiment, as shown in FIG. 5 , the light emitting unit 130 includes a light emitting chip 131 and an encapsulant 132 . The light-emitting chip 131 is disposed on the substrate 120 , the encapsulant 132 covers the light-emitting chip 131 and is at least partially located between the light-emitting chip 131 and the light-shielding layer 140 , and the light-emitting chip 131 is at least partially located between the encapsulant 132 and the substrate 120 . Therefore, the light emitted from the light-emitting chip 131 passes through the encapsulant 132 and is directed toward the light-shielding layer 140 and the inner surface 113 of the secondary lens 110 . In this embodiment, the first width W1 of the light emitting unit 130 is the width of the encapsulant 132 .

In practical applications, the light emitting chip 131 includes, for example, a light emitting diode chip, such as a flip chip (flip chip) light emitting diode chip, but the present invention is not limited thereto. In other implementations, according to actual conditions, the light emitting chip 131 may include other types of solid-state light sources. On the other hand, the encapsulant 132 includes, for example, light-transmitting resin and phosphor, wherein the phosphor is used to provide the function of wavelength conversion, but the present invention is not limited thereto.

Please refer to Figure 6. FIG. 6 is a partially enlarged schematic view of a light emitting device 100 according to still another embodiment of the present invention. In this embodiment, as shown in FIG. 6, the light-emitting unit 130 is at least partially located in the through hole P of the secondary lens 110, and the height H of the light-emitting unit 130 is greater than the first thickness TK1 between the light-emitting surface 111 and the bottom surface 112. Less than 1.5 times of the first thickness TK1. That is, the light emitting unit 130 protrudes from the secondary lens 110 . As mentioned above, since the light-shielding layer 140 can be made of a soft material, the light-shielding layer 140 can cover the light-emitting unit 130 protruding from the secondary lens 110 and be disposed on the light-emitting surface 111 of the secondary lens 110 at the same time. The shortest vertical distance DS is defined between the part of the light-shielding layer 140 contacting the light-emitting surface 111 and the bottom surface 112, so the shortest vertical distance DS is the same as the first thickness TK1 of the secondary lens 110, and the light-shielding layer 140 is located outside the perforation P of the secondary lens 110 And not in the perforation P. In this embodiment, the second thickness TK2 of the light shielding layer 140 is also constant, that is, the second thickness TK2 of the light shielding layer 140 does not change and has a single value.

In summary, the technical solutions disclosed in the above embodiments of the present invention have at least the following advantages:

(1) Since the light-emitting element only includes a single layer of light-shielding layer, and the second thickness of the light-shielding layer is constant, by simply and easily setting the transmittance of the light-shielding layer, the user can accurately control the light-emitting element to pass through the light-shielding layer The brightness of the light emitted by the layer is beneficial to make the brightness provided by the light-emitting element have good uniformity.

(2) Since the light-shielding layer is not located in the perforation of the secondary lens, and the light-shielding layer only needs to be placed on the light-emitting surface of the secondary lens, the manufacturing process of the light-emitting element is simple and easy, which is beneficial to reduce the production cost, and can also effectively improve the light emission. component yield.

(3) Since the ratio of the second width of the secondary lens to the first width of the light-emitting unit is between 5 times and 10 times, the brightness provided by the light-emitting element from the light-emitting surface has good uniformity.

Although the present invention has been disclosed above in terms of implementation, it is not intended to limit the present invention. Anyone skilled in this art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope shall be defined by the appended patent application scope.

100: light emitting element 110: secondary lens 111: light emitting surface 112: bottom surface 113: inner surface 114: Lens body 115: reflective layer 120: Substrate 130: Lighting unit 131: Light emitting chip 132: Packaging glue 140: shading layer A: Range B-B: line segment C: range DS: shortest vertical distance H: height L1, L2, L3, L4, L5: Rays P: perforation TK1: first thickness TK2: second thickness W1: first width W2: second width

FIG. 1 is a schematic perspective view showing a light emitting device according to an embodiment of the present invention. Fig. 2 is a partially enlarged schematic diagram showing the area A in Fig. 1, in which the light-shielding layer is omitted. Fig. 3 is a schematic cross-sectional view along line B-B in Fig. 1 . FIG. 4 is a partially enlarged schematic diagram showing the area C in FIG. 3 . FIG. 5 is a partially enlarged schematic view showing a light emitting device according to another embodiment of the present invention. FIG. 6 is a partially enlarged schematic diagram showing a light emitting device according to still another embodiment of the present invention.

Domestic deposit information (please note in order of depositor, date, and number) none Overseas storage information (please note in order of storage country, institution, date, and number) none

100: light emitting element

110: secondary lens

111: light emitting surface

112: bottom surface

113: inner surface

114: Lens body

115: reflective layer

120: Substrate

130: Lighting unit

140: shading layer

C: range

DS: shortest vertical distance

H: height

P: perforation

TK1: first thickness

TK2: second thickness

Claims (9)

A light-emitting element, comprising: a secondary lens, including an opposite light-emitting surface and a bottom surface, a first thickness is defined between the light-emitting surface and the bottom surface, the secondary lens has a perforation, and the perforation communicates the light-emitting surface and the bottom surface The bottom surface; a substrate, arranged on the bottom surface and covering the through hole; a light-emitting unit, at least partially located in the through hole, the light-emitting unit includes: a light-emitting chip, arranged on the substrate; and a packaging glue, covering the light-emitting chip, The light-emitting chip is at least partially located between the encapsulant and the substrate; and a light-shielding layer is arranged on the light-emitting surface and covers the through hole, and the shortest vertical distance of the light-shielding layer relative to the bottom surface is the same as the first thickness. The glue is at least partly located between the light-emitting chip and the light-shielding layer, and the packaging glue and the light-shielding layer are separated from each other. The light-emitting device according to claim 1, wherein the light-emitting unit has a height which is less than 1.5 times the first thickness and greater than 50 microns. The light-emitting device according to claim 1, wherein the light-shielding layer has a second thickness, and the second thickness is constant. The light emitting device according to claim 1, wherein the light emitting unit and the secondary lens are separated from each other. The light-emitting element according to claim 1, wherein the light-emitting unit has a first width, the secondary lens has a second width, and the ratio of the second width to the first width is between 5 times and 10 times . The light-emitting device according to claim 1, wherein the light-shielding layer is made of soft material. The light-emitting element according to claim 1, wherein the secondary lens comprises: a lens body, the light-emitting surface is located on the lens body; and a reflective layer is arranged on the side of the lens body away from the light-emitting surface, and the bottom surface is located on the lens body. The reflective layer is away from one side of the lens body. The light-emitting device according to claim 7, wherein the reflective layer is a reflective coating. The light-emitting device according to claim 7, wherein the reflective layer is a reflective sheet structure.

Images