CN114420828A - light-emitting device - Google Patents

Abstract

A light-emitting device includes a substrate, a plurality of semiconductor solid-state light sources, a light guide layer, and a plurality of brightness adjustment structures. The semiconductor solid state light source is arranged on the substrate. The light guide layer covers the semiconductor solid state light source and the substrate, and the light guide layer has a roughened upper surface. The roughened upper surface has a concave-convex microstructure. The brightness adjustment structure is disposed on the light guide layer or embedded in the light guide layer. The brightness adjustment structures are respectively located above the semiconductor solid-state light sources for adjusting the brightness of the light emitted by the semiconductor solid-state light sources. The light-emitting device disclosed herein has excellent brightness and uniformity, and can reduce the usage of light-emitting diodes, thereby reducing the manufacturing cost.

Description

light-emitting device

This application is a divisional application of a patent application with an application date of December 27, 2018, an application number of 201811608248.0, and an invention name of "light-emitting device".

technical field

The present invention relates to a light-emitting device.

Background technique

Light-emitting diodes (Light-Emitting diodes, LEDs) have gradually replaced traditional light sources in recent years due to their advantages of small size, high brightness, and low energy consumption. Light emitting diodes have been widely used in backlight modules.

The existing LED backlight module design mainly includes a plurality of LED package components mounted on a circuit board, which has the disadvantage of a short light transmission path. Dark areas appear, resulting in poor visual experience. Although the above problems can be improved by reducing the spacing between the light-emitting diodes, the number of the light-emitting diodes must be increased when the spacing is reduced, which leads to an increase in cost. In addition, since the LED is a point light source, it is often necessary to cover the LED through a plurality of lenses one by one to expand the light-emitting angle of the LED.

Therefore, there is a need for a light emitting module structure that can solve the above problems.

SUMMARY OF THE INVENTION

One aspect of the present invention is to provide a light-emitting device including a substrate, a plurality of semiconductor solid-state light sources, a light guide layer, and a plurality of brightness adjustment structures. The semiconductor solid-state light source is arranged on the substrate. The light guide layer covers the semiconductor solid state light source and the substrate, and the light guide layer has a roughened upper surface. The roughened upper surface has a concave-convex microstructure. The brightness adjustment structure is disposed on the light guide layer or embedded in the light guide layer. The brightness adjustment structures are respectively located above the semiconductor solid-state light sources, and are used for adjusting the brightness of the light emitted by the semiconductor solid-state light sources.

According to some embodiments of the present invention, the roughened upper surface of the light guide layer has an arithmetic mean roughness of 0.08-2 microns.

According to some embodiments of the present invention, the light transmittance of the brightness adjustment structure is 40%-70%.

According to some embodiments of the present invention, the brightness adjustment structure includes a first resin material layer, wherein a plurality of first scattering particles are dispersed in the first resin material layer.

According to some embodiments of the present invention, the first scattering particles comprise _TiO2 .

According to some embodiments of the present invention, the brightness adjustment structure further includes a second resin material layer. The second resin material layer surrounds the first resin material layer, and the plurality of second scattering particles are dispersed in the second resin material layer.

According to certain embodiments of the present invention, the first scattering particles comprise _TiO2 and the second scattering particles comprise _SiO2 .

According to some embodiments of the present invention, the light emitting device further includes a bottom reflection layer and at least one bottom scattering structure. The bottom reflection layer is disposed on the substrate. The bottom scattering structure is disposed on the bottom reflection layer or embedded in the bottom reflection layer.

According to some embodiments of the present invention, the bottom scattering structure includes a third resin material layer, and a plurality of third scattering particles are dispersed in the third resin material layer.

According to some embodiments of the present invention, the light emitting device further includes a plurality of anti-crosstalk structures. The anti-crosstalk structure is arranged on the substrate, and each anti-crosstalk structure is located between the semiconductor solid-state light sources.

According to some embodiments of the present invention, the area of each brightness adjustment structure is larger than the light emitting area of each semiconductor solid-state light source.

According to some embodiments of the present invention, a distance between two adjacent semiconductor solid-state light sources is D1, which satisfies:

Wherein L1 is the length of the semiconductor solid-state light source.

According to some embodiments of the present invention, the light-emitting device further includes a plurality of light-transmitting covers. The light-transmitting cover is disposed on the light-guiding layer, and the light-transmitting cover has a second refractive index lower than the first refractive index of the light-guiding layer. Each light-transmitting cover covers each brightness adjusting structure respectively.

According to some embodiments of the present invention, a cross-sectional shape of the light-transmitting cover is a rectangle, a semicircle or a semiellipse.

According to some embodiments of the present invention, the brightness adjustment structures are embedded in the light guide layer, and the top surface of each brightness adjustment structure is exposed outside the light guide layer.

According to some embodiments of the present invention, the cross-sectional shape of the brightness adjustment structure is a rectangle or an approximately inverted triangle.

According to some embodiments of the present invention, the cross-sectional shape of the brightness adjustment structure is an approximately inverted triangle, and the two sides adjacent to the bottom vertex of the approximately inverted triangle are recessed inward.

According to some embodiments of the present invention, the light guide layer has at least two side surfaces that are coplanar with the two side surfaces of the substrate, respectively.

According to some embodiments of the present invention, both side surfaces of the light guide layer are smooth and do not have a concave-convex microstructure.

According to some embodiments of the present invention, the substrate is a rectangular substrate.

According to some embodiments of the present invention, the light guide layer includes silicone resin, epoxy resin or acrylic glue.

According to certain embodiments of the present invention, the semiconductor solid state light source is a light emitting diode die or a light emitting diode package or a wafer level package light emitting diode (CSP LED).

Another aspect of the present invention is to provide a light-emitting device including a substrate, a plurality of semiconductor solid-state light sources, a light guide layer, and a plurality of brightness adjustment structures. The semiconductor solid-state light source is arranged on the substrate. The light guide layer covers the semiconductor solid state light source and the substrate, and the light guide layer has a smooth upper surface. The brightness adjustment structure is embedded in the light guide layer. The brightness adjustment structures are respectively located above the semiconductor solid state light sources for adjusting the brightness of the light emitted by the semiconductor solid state light sources, and the top surfaces of the brightness adjustment structures are not exposed to the light guide layer.

According to some embodiments of the present invention, the light transmittance of the brightness adjustment structure is 40%-70%.

According to some embodiments of the present invention, the light emitting device further includes a bottom reflection layer and at least one bottom scattering structure. The bottom reflection layer is disposed on the substrate. The bottom scattering structure is embedded in the bottom reflective layer.

According to some embodiments of the present invention, the area of each brightness adjustment structure is larger than the light emitting area of each semiconductor solid-state light source.

Another aspect of the present invention is to provide a light-emitting device including a substrate, a plurality of semiconductor solid-state light sources, and a light guide layer. The semiconductor solid-state light source is arranged on the substrate. The light guide layer covers a plurality of semiconductor solid-state light sources and the substrate, and the light guide layer has a smooth upper surface. The smooth upper surface has a plurality of concave portions, and each concave portion is respectively located above each semiconductor solid-state light source. The recess is configured to adjust the brightness of light emitted by the semiconductor solid state light source.

According to some embodiments of the invention, the bottom of the recess is pointed.

According to some embodiments of the present invention, the cross-sectional shape of the recess is approximately V-shaped.

According to some embodiments of the present invention, the two sides of the approximately V-shape are inwardly recessed.

Description of drawings

Various aspects of the present disclosure may be better understood from the following detailed description when read in conjunction with the accompanying drawings. It should be noted that in accordance with standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or decreased in order to clarify the discussion.

FIG. 1A is a schematic perspective view of a light-emitting device according to some embodiments of the present disclosure;

1B is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

2A is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

2B is a schematic top view of a light emitting device according to some embodiments of the present disclosure;

3 is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

4 is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

5 is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

6 is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

7 is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

8A is a schematic perspective view of a light-emitting device according to some embodiments of the present disclosure;

8B is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

9 is a schematic cross-sectional view of a light-emitting device according to some embodiments of the present disclosure;

10A-10F illustrate photographs of the light-emitting device in operation according to some embodiments of the present disclosure.

Detailed ways

The following disclosure provides many different embodiments or examples for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. Of course, these are only examples and are not intended to limit the present disclosure. By way of example, embodiments in the ensuing description where forming a first feature over or on a second feature may include forming direct contact between the first feature and the second feature may also include embodiments where the first feature and the second feature are in direct contact. Embodiments in which additional features are formed between the second features so that the first and second features are not in direct contact. Additionally, the present disclosure may repeat reference numerals and/or letters throughout the examples. This repetition is for the purpose of simplicity and clarity, and does not in itself indicate a relationship between the various embodiments and/or configurations discussed.

In addition, spatially relative terms, such as "below," "below," "lower," "above," "upper," and the like, are used herein to simplify the description of one element or feature shown in the figures compared to another element ( or elements) or feature (or features). In addition to the orientation depicted in the figures, spatially relative terms are intended to encompass different orientations of the device in use or operation. The device may be oriented in different directions (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Please refer to FIG. 1A and FIG. 1B at the same time. 1A illustrates a schematic perspective view of a light-emitting device 10a according to some embodiments of the present disclosure, and FIG. 1B illustrates a schematic cross-sectional view of the light-emitting device 10a taken along the line B-B″ of FIG. 1A . As shown in FIGS. 1A and 1B The light-emitting device 10a includes a substrate 110, a plurality of semiconductor solid-state light sources 200, a light guide layer 300, and a plurality of brightness adjustment structures 400. The light-emitting device 10a may also include other elements, which will be described below.

Substrate 110 may comprise any suitable substrate. In some embodiments, the substrate 110 may be a transparent substrate or an opaque substrate. In some embodiments, the substrate 110 may be a flexible substrate. Therefore, the light emitting device 10a can be applied to a light emitting module in the form of a highly curved backlight. In other embodiments, the substrate 110 may be a rigid substrate. For example, the substrate 110 may be a sapphire substrate, a silicon substrate, a glass substrate, a printed circuit board, a metal substrate, or a ceramic substrate, but is not limited thereto. As shown in FIG. 1A , the substrate 110 may be a rectangular substrate.

In some embodiments, the substrate 110 may also include conductive structures 118 (as shown in FIG. 1B ). Therefore, in some embodiments, the substrate 110 may be electrically connected to the electrode 112 of the semiconductor solid state light source 200 through the conductive structure 118 . In addition, in some embodiments, the substrate 110 may further include an insulating material 116 (as shown in FIG. 1B ) located below the substrate 110 .

A plurality of semiconductor solid-state light sources 200 are disposed on the substrate 110 . In some embodiments, the semiconductor solid state light source 200 is a light emitting diode die that can emit light of any wavelength. For example, the semiconductor solid state light source 200 may be a blue light emitting diode chip or an ultraviolet light emitting light emitting diode chip. Furthermore, the semiconductor solid state light source 200 may be any size LED die. For example, in some embodiments, the semiconductor solid-state light source 200 may be a sub-millimeter light emitting diode chip (Mini LED chip) or a micro light emitting diode chip (Micro LED chip), but not limited thereto. The side length dimension of the "sub-millimeter light emitting diode wafer" may be about 100 microns, 150 microns, 200 microns, 250 microns, 300 microns, 350 microns or 400 microns. The side length dimension of the "micro-LED wafer" is about 100 microns or less, for example, about 30 microns, 40 microns, 50 microns, 60 microns, 70 microns, 80 microns or 90 microns. In addition, in some embodiments, the semiconductor solid-state light source 200 may be a light-emitting diode package (LED package) or a chip-scale package LED (ChipScale Package LED, CSP LED for short).

The light guide layer 300 covers the semiconductor solid state light source 200 and the substrate 110 . Specifically, the light guide layer 300 has a roughened upper surface 300a. It should be noted that the roughened upper surface 300a of the light guide layer 300 provides specific technical effects, which will be described in detail below. As shown in FIG. 1B , the light guide layer 300 has at least two side surfaces 300b and 300c that are coplanar with the two side surfaces 110b and 110c of the substrate 110 , respectively. The light guide layer 300 includes any suitable transparent adhesive. For example, in some embodiments, the light guide layer 300 includes silicone resin, epoxy resin or acrylic adhesive, but not limited thereto. Additionally, in certain embodiments, the refractive index of the light directing layer 300 is about 1.49 to about 1.6.

A plurality of brightness adjustment structures 400 are disposed on the light guide layer 300 . Specifically, each brightness adjustment structure 400 is located above each semiconductor solid state light source 200 , and has the effect of partially transmitting light and partially reflecting light, so as to adjust the brightness of the light emitted by each semiconductor solid state light source 200 . In detail, since the light emitting diode chip has high directivity, in the conventional light emitting device, the brightness of the light directly above the light emitting diode chip is relatively high, so that the light output of the light emitting device is uneven. According to various embodiments of the present disclosure, the brightness of the light located above the semiconductor solid state light source 200 can be adjusted through the setting of the brightness adjustment structure 400 , so that the light output of the light emitting device 10 a is more uniform. In more detail, a part of the light emitted by the semiconductor solid-state light source 200 passes through and transmits the brightness adjustment structure 400 , and another part of the light is reflected when passing through the brightness adjustment structure 400 .

In order for the brightness adjustment structure 400 to effectively adjust the brightness of the light emitted by the semiconductor solid state light source 200 , the area of the brightness adjustment structure 400 is larger than the light emitting area of the semiconductor solid state light source 200 , as shown in FIGS. 1A and 1B . In some embodiments, the brightness adjustment structure 400 has a length L (or diameter), which satisfies the following formula:

D1 is the distance between two adjacent semiconductor solid-state light sources 200 ; L1 is the length of the semiconductor solid-state light sources 200 .

In addition, in some embodiments, the light transmittance of the brightness adjustment structure 400 is 40%˜70%, such as 45%, 50%, 55% or 65%. The brightness adjustment structure 400 may be one or more layers of resin material. As shown in FIG. 1B , the brightness adjustment structure 400 includes a first resin material layer 410 . Specifically, a plurality of first scattering particles (not shown) are dispersed in the first resin material layer 410 to scatter or reflect light passing through the first resin material layer 410 . In some embodiments, the first resin material layer 410 includes silicone resin, epoxy resin or acrylic glue, and the refractive index of the first resin material layer 410 is about 1.49 to about 1.6. In some embodiments, the first scattering particles comprise TiO ₂ , but are not limited thereto.

As previously mentioned, the roughened upper surface 300a of the light guide layer 300 provides a specific technical effect. Specifically, the light guide layer 300 is obtained by forming a resin material layer and then roughening the upper surface of the resin material layer by chemical etching or physical polishing. Therefore, the roughened upper surface 300a has a concave-convex microstructure (not shown). In this way, the adhesiveness between the subsequently formed brightness adjustment structure 400 and the light guide layer 300 can be effectively improved, and the risk of peeling off between the two can be reduced. On the other hand, when the light emitted by the semiconductor solid state light source 200 passes through the roughened upper surface 300a, the concave-convex microstructure of the roughened upper surface 300a can scatter the light, thereby making the light output of the light emitting device 10a more uniform. In some embodiments, the roughened upper surface 300a has an arithmetic mean roughness (Ra) of 0.08-2 microns. In some embodiments, roughening is performed only on the upper surface of the resin material layer, so the two side surfaces 300b and 300c of the formed light guide layer 300 are smooth and do not have a concave-convex microstructure.

In some embodiments, the light-emitting device 10a further includes a bottom reflection layer 500 disposed on the substrate 110 (as shown in FIG. 1B ). In some embodiments, the bottom reflection layer 500 includes a specular metal material, such as silver, aluminum, etc., but not limited thereto. It should be understood that, for the sake of clarity, other elements such as the bottom scattering structure and the anti-crosstalk structure are not shown in FIG. 1B , but the light emitting device 10a may also include other elements such as the bottom scattering structure and the anti-crosstalk structure, which will be described below. Describe in detail.

By disposing the brightness adjustment structure 400, the bottom reflective layer 500, and making the light guide layer 300 have a roughened upper surface 300a, the distance that the light emitted by the semiconductor solid state light source 200 transmits in the light guide layer 300 can be increased, and the light-emitting device can be improved. The light output of 10a is more uniform. Accordingly, the brightness of the emitted light can be maintained and the uniformity of the emitted light can be increased without reducing the spacing between the light-emitting diodes. Specifically, as shown in FIG. 1B , a distance between two adjacent semiconductor solid-state light sources 200 is D1, which satisfies the following formula:

Wherein L1 is the length of the semiconductor solid state light source 200 .

Please refer to FIG. 2A and FIG. 2B . 2A is a schematic cross-sectional view of a light emitting device 10b according to some embodiments of the present disclosure, and FIG. 2B is a schematic top view of the light emitting device 10b. It should be noted that, in FIGS. 2A and 2B , the same or similar elements as those in FIGS. 1A and 1B are given the same symbols, and the related descriptions are omitted. The light emitting device 10b of FIGS. 2A and 2B is similar to the light emitting device 10a of FIGS. 1A and 1B , except that the brightness adjustment structure 400 of the light emitting device 10b further includes a second resin material layer 420 .

The second resin material layer 420 surrounds the first resin material layer 410 (as shown in FIG. 2B ). Specifically, a plurality of second scattering particles (not shown) are dispersed in the second resin material layer 420 to scatter or reflect light passing through the second resin material layer 420 . In some embodiments, the second resin material layer 420 includes silicone resin, epoxy resin or acrylic, and the refractive index of the second resin material layer 420 is about 1.49 to about 1.6. In some embodiments, the second scattering particles include SiO2, but not limited thereto.

Please refer to Figure 3. FIG. 3 is a schematic cross-sectional view of a light emitting device 10c according to some embodiments of the present disclosure. It should be noted that, in FIG. 3 , the same or similar elements as those in FIGS. 1A and 1B are given the same symbols, and the related descriptions are omitted. The light-emitting device 10c of FIG. 3 is similar to the light-emitting device 10a of FIGS. 1A and 1B , except that the light-emitting device 10c further includes a plurality of bottom scattering structures 600 disposed on the bottom reflection layer 500 .

In some embodiments, the bottom scattering structure 600 includes a third resin material layer. Specifically, a plurality of third scattering particles are dispersed in the third resin material layer to scatter light passing through the third resin material layer. In some embodiments, the third resin material layer includes silicone resin, epoxy resin or acrylic, and the refractive index of the third resin material layer is about 1.49 to about 1.6. In some embodiments, the third scattering particles include TiO ₂ or SiO ₂ , but are not limited thereto.

As shown in FIG. 3 , the sizes of the bottom scattering structures 600 may be different. In detail, the size of the bottom scattering structure 600 that is closer to the semiconductor solid-state light source 200 may be smaller, and the size of the bottom scattering structure 600 that is farther from the semiconductor solid-state light source 200 may be larger. This is because, at a position closer to the semiconductor solid-state light source 200 , the less light is reflected therethrough by the brightness adjustment structure 400 . On the contrary, the farther away from the semiconductor solid-state light source 200 is (ie, the middle of the two semiconductor solid-state light sources 200 in FIG. 3 ), the more light is reflected by the brightness adjustment structure 400 . Accordingly, adjusting the size of the bottom scattering structure 600 to increase the light receiving area can increase the scattering efficiency of the bottom scattering structure 600 . However, it should be understood that the positions, numbers and sizes of the bottom scattering structures 600 shown in FIG. 3 are only examples, and the sizes of the plurality of bottom scattering structures 600 may also be the same, and the number and size of the bottom scattering structures 600 may be selected according to requirements. Location.

Please refer to Figure 4. FIG. 4 is a schematic cross-sectional view of a light emitting device 10d according to some embodiments of the present disclosure. It should be noted that, in FIG. 4 , the same or similar elements as those in FIGS. 1A and 1B are given the same symbols, and the related descriptions are omitted. The light-emitting device 10d of FIG. 4 is similar to the light-emitting device 10a of FIGS. 1A and 1B , except that the light-emitting device 10d further includes a plurality of light-transmitting covers 800 disposed on the light guide layer 300 .

As shown in FIG. 4 , each light-transmitting cover 800 covers each brightness adjusting structure 400 respectively. In other words, each light-transmitting cover 800 is located above each of the semiconductor solid-state light sources 200 , respectively. The light-transmitting cover 800 can make the light output of the light-emitting device 10d more uniform. Specifically, after a part of the light emitted by the semiconductor solid-state light source 200 passes through the brightness adjustment structure 400 and is transmitted into the light-transmitting cover 800, it can be totally reflected at the interface between the light-transmitting cover 800 and the air, so as to further adjust the light in the semiconductor solid-state light source. The brightness of the light above the light source 200 makes the light output of the light emitting device 10d more uniform.

Furthermore, in some embodiments, the refractive index of the light transmissive cover 800 is lower than the refractive index of the light guide layer 300 . In certain embodiments, the refractive index of the light transmissive cover 800 is about 1.39 to about 1.48. Accordingly, when the light emitted by the semiconductor solid-state light source 200 enters the light-transmitting cover 800 with a lower refractive index from the light-guiding layer 300 with a higher refractive index, the light has the opportunity to be totally reflected to increase the intensity of the light in the light-guiding layer 300 . The transmission distance is increased, thereby making the light output of the light-emitting device 10d more uniform.

Please refer to Figure 5. FIG. 5 is a schematic cross-sectional view of a light emitting device 10e according to some embodiments of the present disclosure. It should be noted that, in FIG. 5 , the same or similar elements as those in FIG. 4 are given the same symbols, and the related descriptions are omitted. The light-emitting device 10e of FIG. 5 is similar to the light-emitting device 10d of FIG. 4 , except that the cross-sectional shape of the light-transmitting cover 800 of the light-emitting device 10d is a rectangle, while the cross-sectional shape of the light-transmitting cover 800 of the light-emitting device 10e is a semi-ellipse ( Viewed from the schematic cross-sectional views shown in Figures 4 and 5).

Specifically, the cross-sectional shape of the transparent cover 800 is configured as a semi-elliptical shape (ie the transparent cover 800 is in the shape of a lens and has a curved surface) to increase the chance of total reflection of light at the interface between the transparent cover 800 and the air. In some other embodiments, the cross-sectional shape of the light-transmitting cover 800 may also be a semicircle or other shapes.

Please refer to Figure 6. 6 is a schematic cross-sectional view of a light emitting device 10f according to some embodiments of the present disclosure. It should be noted that, in FIG. 6 , the same or similar elements as those in FIGS. 1A and 1B are given the same symbols, and the related descriptions are omitted. The light-emitting device 10f of FIG. 6 is similar to the light-emitting device 10a of FIGS. 1A and 1B , except that the brightness adjustment structure 400 of the light-emitting device 10f is embedded in the light guide layer 300 . In addition, the light emitting device 10f further includes a plurality of bottom scattering structures 600 and a plurality of anti-crosstalk structures 700 .

Specifically, the top surface 400 a of the brightness adjustment structure 400 of the light emitting device 10 f is exposed to the outside of the light guide layer 300 . In some embodiments, the top surface 400a of the brightness adjustment structure 400 is coplanar with the roughened top surface 300a of the light guide layer 300 .

As shown in FIG. 6 , the bottom scattering structure 600 is embedded in the bottom reflection layer 500 . The anti-crosstalk structure 700 is disposed on the substrate 110 , and the anti-crosstalk structure 700 is located between the semiconductor solid-state light sources 200 . The anti-crosstalk structure 700 can scatter and/or reflect the light from the semiconductor solid-state light source 200 to prevent the light from interfering with each other. In some embodiments, the anti-crosstalk structure 700 includes cones or pillars, but is not limited thereto. In some embodiments, the height of the anti-crosstalk structure 700 is greater than or equal to the height of the semiconductor solid state light source 200 .

In some embodiments, a plurality of fourth scattering particles are dispersed in the anti-crosstalk structure 700 to scatter and/or reflect light passing through the anti-crosstalk structure 700 . In some embodiments, the anti-crosstalk structure 700 includes silicone, epoxy, or acrylic, and the refractive index of the anti-crosstalk structure 700 is about 1.49 to about 1.6. In some embodiments, the fourth scattering particles include TiO ₂ , SiO ₂ , etc., but are not limited thereto.

Please refer to Figure 7. 7 is a schematic cross-sectional view of a light emitting device 10g according to some embodiments of the present disclosure. It should be noted that, in FIG. 7 , the same or similar elements as those in FIGS. 1A and 1B are given the same symbols, and the related descriptions are omitted. The light emitting device 10g of FIG. 7 is similar to the light emitting device 10a of FIGS. 1A and 1B , except that the brightness adjustment structure 400 of the light emitting device 10g is embedded in the light guide layer 300 , and the top surface 400a of each brightness adjustment structure 400 is not exposed outside the light guide layer 300 . The light emitting device 10g further includes a plurality of bottom scattering structures 600 embedded in the bottom reflective layer 500 .

In addition, compared to the light guide layer 300 of the light emitting device 10a having a roughened upper surface 300a (as shown in FIG. 1B ), the light guide layer 300 of the light emitting device 10g has a smooth upper surface 300a ″ (as shown in FIG. 7 ). That is, when the light guide layer 300 of the light emitting device 10g is formed (for example, formed by molding), chemical etching or physical polishing is not performed to roughen the upper surface of the light guide layer 300. The reason for this is that the inventors found through research that , when the brightness adjustment structure 400 is embedded in the light guide layer 300, and the top surface 400a of the brightness adjustment structure 400 is not exposed outside the light guide layer 300, the smooth upper surface 300a" can adjust the light above the semiconductor solid-state light source 200 brightness. Specifically, compared with the rough upper surface, when light is transmitted from the smooth upper surface 300 a ″ to the air, total reflection is more likely to occur. Therefore, after passing through the brightness adjustment structure 400 , a part of the light emitted by the semiconductor solid-state light source 200 can be The smooth upper surface 300a" is totally reflected, thereby increasing the transmission distance of light, and making the light output of the light emitting device 10g more uniform.

Please refer to FIG. 8A and FIG. 8B at the same time. 8A shows a schematic perspective view of a light-emitting device 10h according to some embodiments of the present disclosure, and FIG. 8B shows a schematic cross-sectional view of the light-emitting device 10h taken along the line B-B″ of FIG. 8A . It should be noted that in FIG. 8A And in Fig. 8B, the same or similar elements with Fig. 1A and Fig. 1B are given the same symbol, and omit the relevant description.The light-emitting device 10h of Fig. 8A and Fig. 8B is similar to the light-emitting device 10a of Fig. 1A and Fig. 1B, the difference lies in , the roughened upper surface 300a of the light guide layer 300 of the light-emitting device 10h has a plurality of concave portions 310. Each concave portion 310 is located above each semiconductor solid-state light source 200, and the bottom of the concave portion 310 is pointed. Specifically, the cross-sectional shape of the concave portion 310 It is an approximately V-shape (viewed from the schematic cross-sectional view shown in FIG. 8B ). More specifically, the two sides S1 and S2 of the approximately V-shape are recessed inward.

Each brightness adjustment structure 400 is embedded in each concave portion 310 of the light guide layer 300 , and the top surface 400 a of the brightness adjustment structure 400 is exposed outside the light guide layer 300 . In some embodiments, the top surface 400a of the brightness adjustment structure 400 is coplanar with the roughened top surface 300a of the light guide layer 300 . It should be noted that, compared with the cross-sectional shape of the brightness adjustment structure 400 of the light emitting device 10a being a rectangle (viewed from the schematic cross-sectional view shown in FIG. 1B ), the cross-sectional shape of the brightness adjustment structure 400 of the light emitting device 10h is an approximately inverted triangle ( Viewed from the schematic cross-sectional view shown in FIG. 8B ). Specifically, the two sides S1 and S2 adjacent to the bottom vertex of the approximately inverted triangle are concave inward. Accordingly, the brightness adjustment structure 400 is configured in a cone shape as shown in FIG. 8A and FIG. 8B , which increases the scattering or reflection effect of the brightness adjustment structure 400 .

Please refer to Figure 9. FIG. 9 is a schematic cross-sectional view of a light emitting device 10i according to some embodiments of the present disclosure. It should be noted that, in FIG. 9 , the same or similar elements as those in FIG. 8B are given the same symbols, and the related descriptions are omitted. The light emitting device 10i of FIG. 9 is similar to the light emitting device 10h of FIGS. 8A and 8B, except that, compared with the light guide layer 300 of the light emitting device 10h having a roughened upper surface 300a (as shown in FIG. 8B ), the light emitting device 10i has a roughened upper surface 300a. The light guide layer 300 has a smooth upper surface 300a" (as shown in FIG. 9). That is, when the light guide layer 300 of the light emitting device 10i is formed (eg, formed by molding), chemical etching or physical grinding is not performed to roughen it the upper surface of the light guide layer 300 .

As mentioned above, compared with the rough upper surface, when light is transmitted from the smooth upper surface 300a" to the air, total reflection is more likely to occur. Therefore, the light emitting device 10i may not have the brightness adjustment structure. Instead, the light emitting device 10i may be The light guide layer 300 is configured to have a smooth upper surface 300a", and the plurality of concave portions 310 of the smooth upper surface 300a" are respectively located above the semiconductor solid-state light sources 200 to adjust the brightness of the light above the semiconductor solid-state light sources 200, so as to emit light. The light output of the device 10i is more uniform. Specifically, as shown in Figure 9, the cross-sectional shape of the concave portion 310 is approximately V-shaped (viewed from the schematic cross-sectional view shown in Figure 9). More specifically, the approximately V-shaped two sides S3 , S4 is recessed inward.

Please refer to FIGS. 10A to 10F . 10A-10F illustrate photographs of the light-emitting device in operation according to some embodiments of the present disclosure. FIG. 10A is a photo of the light-emitting device without the brightness adjustment structure during operation. 10B and FIG. 10C are photos of two light-emitting devices with brightness adjustment structures in operation, wherein the brightness adjustment structures are embedded in the light guide layer, and the top surfaces of the brightness adjustment structures are exposed outside the light guide layer. It can be clearly seen from FIGS. 10A to 10C that the light-emitting devices of FIGS. 10B and 10C have better brightness and uniformity than the light-emitting device of FIG. 10A . In addition, the light emitting device of FIG. 10C has the best brightness and uniformity because the light emitting device of FIG. 10C has a larger area of the brightness adjustment structure, so that the brightness of the light above the semiconductor solid state light source can be adjusted more effectively.

FIGS. 10D to 10F are respectively photos of the three light-emitting devices with brightness adjustment structures in operation, wherein the brightness adjustment structures are embedded in the light guide layer, and the top surfaces of the brightness adjustment structures are not exposed outside the light guide layer. In detail, the light emitting device of FIG. 10F has the brightness adjustment structure with the largest area, the light emitting device of FIG. 10E has the brightness adjustment structure of the second largest area, and the light emitting device of FIG. 10D has the brightness adjustment structure of the smallest area. It can be clearly seen from FIGS. 10A and 10D to 10F that the light-emitting device of FIGS. 10D to 10F has better brightness and uniformity than the light-emitting device of FIG. 10A . In addition, the light emitting device of FIG. 10F (which has the largest area brightness adjustment structure) has the best brightness and uniformity.

As described above, according to embodiments of the present disclosure, the optical design of the light guide layer of the light emitting device (eg, the light guide layer has a recess above the semiconductor solid state light source, the light guide layer upper surface is a smooth upper surface or a roughened upper surface surface), and the arrangement of various optical elements (such as brightness adjustment structure, bottom reflective layer, bottom scattering structure, and anti-crosstalk structure, etc.), so that the light emitted by the semiconductor solid-state light source can be more uniformly distributed and the light can be transmitted. farther. Therefore, the light emitting device of the present disclosure can reduce the usage amount of the light emitting diode, thereby reducing the manufacturing cost.

The foregoing outlines the features of several embodiments so that those skilled in the art may better understand aspects of the present disclosure. Those skilled in the art should appreciate that the present disclosure may be readily utilized as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments described herein. Those skilled in the art should also realize that such equivalent structures do not depart from the spirit and scope of the present disclosure, and that various changes, substitutions and alterations herein can be made without departing from the spirit and scope of the present disclosure.

Claims (14)

1. A light-emitting device, characterized in that, comprising: a substrate; a plurality of semiconductor solid-state light sources, disposed on the substrate; a light guide layer directly covering the plurality of semiconductor solid-state light sources and the substrate, the light guide layer has a roughened upper surface, wherein the roughened upper surface has a concave-convex microstructure; and a plurality of brightness adjustment structures disposed on the light guide layer, wherein each of the brightness adjustment structures is located above each of the semiconductor solid-state light sources, respectively, for adjusting the brightness of the light emitted by each of the semiconductor solid-state light sources; Wherein, the plurality of brightness adjustment structures include a first resin material layer and a second resin material layer, a plurality of first scattering particles are dispersed in the first resin material layer, and the second resin material layer surrounds the first resin material layer A resin material layer, and a plurality of second scattering particles are dispersed in the second resin material layer, the plurality of first scattering particles include TiO ₂ , and the plurality of second scattering particles include SiO ₂ . 2 . The light-emitting device of claim 1 , wherein the roughened upper surface of the light guide layer has an arithmetic mean roughness of 0.08˜2 μm. 3 . 3 . The light-emitting device according to claim 1 , wherein the light transmittance of the plurality of brightness adjustment structures is 40% to 70%. 4 . 4. The light-emitting device of claim 1, further comprising: a bottom reflective layer disposed on the substrate; and At least one bottom scattering structure is disposed on the bottom reflection layer or embedded in the bottom reflection layer. 5 . The light-emitting device of claim 4 , wherein the at least one bottom scattering structure comprises a third resin material layer, and a plurality of third scattering particles are dispersed in the third resin material layer. 6 . 6. The light-emitting device of claim 1, further comprising: A plurality of anti-crosstalk structures are disposed on the substrate, and each of the anti-crosstalk structures is located between the plurality of semiconductor solid-state light sources. 7 . The light-emitting device of claim 1 , wherein an area of each of the brightness adjustment structures is larger than a light-emitting area of each of the semiconductor solid-state light sources. 8 . 8. The light-emitting device according to claim 1, wherein a distance between two adjacent semiconductor solid-state light sources is D1, which satisfies the following formula:

Wherein L1 is a length of the semiconductor solid state light source. 9 . The light-emitting device of claim 1 , wherein a cross-sectional shape of the plurality of brightness adjustment structures is a rectangle. 10 . 10 . The light-emitting device of claim 1 , wherein the light guide layer has at least two side surfaces that are coplanar with the two side surfaces of the substrate, respectively. 11 . 11 . The light-emitting device of claim 10 , wherein the at least two side surfaces of the light guide layer are smooth and do not have concave-convex microstructures. 12 . 12. The light-emitting device of claim 1, wherein the substrate is a rectangular substrate. 13 . The light-emitting device of claim 1 , wherein the light guide layer comprises silicone resin, epoxy resin or acrylic glue. 14 . 14. The light emitting device of claim 1, wherein the plurality of semiconductor solid state light sources are a plurality of light emitting diode chips or a plurality of light emitting diode packages or a plurality of wafer level package light emitting diodes (CSP LEDs).

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