TWI894056B - Display apparatus - Google Patents

Abstract

A display apparatus including a substrate, a light emitting device and a bank structure is provided. The light emitting device is bonded on the substrate, and has a light emitting surface facing away from the substrate and a first edge and a second edge intersecting each other. A length of the first edge along a first direction is greater than a length of the second edge along a second direction. The bank structure is disposed on the substrate, and surrounds the light emitting device. The bank structure has a first portion and a second portion. The first portion is disposed facing the first edge of the light emitting device along the second direction. The second portion is disposed facing the second edge of the light emitting device along the first direction. The first portion and the second portion of the bank structure respectively have a first top surface and a second top surface facing away from the substrate. In a normal direction of the light emitting surface, the first top surface is lower than the light emitting surface, and the second top surface is higher than the light emitting surface.

Description

Display device

The present invention relates to a display device, and in particular to a display device provided with a light-emitting element.

In self-luminous display devices, the light-emitting element can emit light in both a forward and sideways direction. To increase the frontal brightness of the display, in addition to improving the light-emitting efficiency of the light-emitting element itself, a concept has been proposed to guide the sidelight emitted by the light-emitting element to the forward light-emitting surface.

For example, a high-reflectivity baffle structure can be placed on the side light-emitting surface of a light-emitting device to reflect side light and increase its probability of exiting from the front light-emitting surface. Generally, designing the baffle structure higher than the light-emitting surface of the light-emitting device maximizes the reuse of side light. However, the optical performance of the various film layers on the baffle structure can be easily degraded due to positional offset caused during the bonding process between the light-emitting device and the substrate.

The present invention provides a display device that can take both light extraction efficiency and color performance into consideration.

The display device of the present invention includes a substrate, a light-emitting element and a baffle structure. The light-emitting element is bonded to the substrate and has a light-emitting surface facing away from the substrate and a first edge and a second edge defining the light-emitting surface. The first edge and the second edge extend in a first direction and a second direction, respectively. The length of the first edge along the first direction is greater than the length of the second edge along the second direction. The first direction and the second direction are parallel to the substrate surface of the substrate and intersect with each other. The baffle structure is arranged on the substrate and is arranged around the light-emitting element. The baffle structure has a first part and a second part. The first part is arranged along the second direction facing the first edge of the light-emitting element. The second part is arranged along the first direction facing the second edge of the light-emitting element. The first part and the second part of the baffle structure have a first top surface and a second top surface facing away from the substrate, respectively. In the normal direction of the substrate surface, the first top surface is lower than the light-emitting surface of the light-emitting element, and the second top surface is higher than the light-emitting surface of the light-emitting element.

Based on the above, in a display device according to one embodiment of the present invention, a light-emitting element disposed on a surface of a substrate has a first edge and a second edge defining a light-emitting surface and extending in directions intersecting with each other, and the length of the first edge is greater than the length of the second edge. A baffle structure disposed around the light-emitting element has a first portion and a second portion disposed opposite the first edge and the second edge of the light-emitting element, respectively. Because the second top surface of the second portion of the baffle structure is higher than the light-emitting surface of the light-emitting element, the light-emitting efficiency of the light-emitting element can be effectively improved. On the other hand, by making the first top surface of the first portion of the baffle structure lower than the light-emitting surface of the light-emitting element, the large viewing angle deviation of the display device caused by the positional offset when the light-emitting element is bonded to the substrate can be significantly improved.

As used herein, "about," "approximately," "substantially," or "substantially" include the stated value and the average within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, taking into account the measurement in question and the particular amount of error associated with the measurement (i.e., the limitations of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value, or, for example, within ±30%, ±20%, ±15%, ±10%, ±5%. Furthermore, as used herein, "about," "approximately," "substantially," or "substantially" can be used to select an acceptable range of deviation or standard deviation depending on the measured property, cutting property, or other property, and may not apply to all properties without using a single standard deviation.

In the accompanying drawings, the thickness of layers, films, panels, regions, etc., is exaggerated for clarity. It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element, or intervening elements may also exist. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements. As used herein, "connected" can refer to physical and/or electrical connections. Furthermore, "electrically connected" can mean the presence of other elements between two elements.

Furthermore, relative terms such as "lower" or "bottom" and "upper" or "top" may be used herein to describe the relationship of one element to another element, as illustrated in the figures. It will be understood that relative terms are intended to encompass different orientations of a device in addition to the orientations illustrated in the figures. For example, if a device in one of the figures were flipped over, an element described as being on the "lower" side of the other elements would be oriented on the "upper" side of the other elements. Thus, the exemplary term "lower" can encompass both "lower" and "upper" orientations, depending on the particular orientation of the figure. Similarly, if a device in one of the figures were flipped over, an element described as being "below" or "beneath" other elements would be oriented "above" the other elements. Thus, the exemplary terms "above" or "below" can encompass both "above" and "below" orientations.

Exemplary embodiments are described herein with reference to cross-sectional illustrations that are schematic representations of idealized embodiments. Therefore, variations in the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, the embodiments described herein should not be construed as limited to the specific shapes of regions as illustrated herein, but rather include deviations in shape that result, for example, from manufacturing. For example, regions illustrated or described as flat may typically have rough and/or nonlinear features. Furthermore, sharp corners that are illustrated may be rounded. Therefore, the regions illustrated in the figures are schematic in nature, and their shapes are not intended to illustrate the precise shape of the regions and are not intended to limit the scope of the claims.

Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals are used in the drawings and the description to refer to the same or like parts.

FIG1 is a schematic front view of a display device according to a first embodiment of the present invention. FIG2A and FIG2B are enlarged schematic views of a local area of the display device of FIG1. FIG3A and FIG3B are schematic cross-sectional views of the display device of FIG2A. FIG4 is an enlarged schematic view of a local area of the display device of FIG2A. FIG5A to FIG5J and FIG6A to FIG6J are schematic cross-sectional views of the manufacturing process of the display device of FIG3A and FIG3B. FIG3A corresponds to the section line A-A’ of FIG2A and FIG2B. FIG3B corresponds to the section line B-B’ of FIG2A and FIG2B. For clarity of presentation, FIG2B omits the illustration of the light-shielding structure 170 in FIG2A.

Referring to Figures 1 and 2A , the display device 10 includes a substrate 100 and a plurality of light-emitting elements 120. In this embodiment, the substrate 100 is, for example, a circuit board having a pixel circuit layer (not shown) and a plurality of bonding pads 105. The light-emitting elements 120 are adapted to be bonded to the bonding pads 105 to electrically connect to the substrate 100. The plurality of light-emitting elements 120 may be bonded to a plurality of pixel areas PA on the substrate 100, respectively, to form a plurality of display pixels of the display device 10. In this embodiment, each display area PA may be bonded with three light-emitting elements 120 of different luminous colors (e.g., red, green, and blue, but not limited thereto), such as light-emitting element 121, light-emitting element 122, and light-emitting element 123.

In this embodiment, the display device 10 further includes a plurality of light-transmitting areas TA. These light-transmitting areas TA are, for example, arranged in multiple rows and columns along directions X and Y, and are spaced apart from one another, where direction X intersects with (e.g., is perpendicular to) direction Y. In other words, these light-transmitting areas TA may be arranged in an array on the substrate 100. Of particular note is that a plurality of pixel areas PA are disposed in the spacing regions between these light-transmitting areas TA. In this embodiment, the aforementioned spacing regions are defined by the light-shielding structure 170 of the display device 10. The light-shielding structure 170 includes a plurality of openings OP2 within each pixel area PA, and these openings OP2 overlap with the light-emitting element 121, the light-emitting element 122, and the light-emitting element 123 along direction Z, respectively.

Referring to Figures 2A, 3A, and 3B, in this embodiment, the light-emitting element 120 may be a micro light-emitting diode (micro-LED) and include a first electrode E1, a second electrode E2, and an epitaxial structure layer. The epitaxial structure layer may include a first-type semiconductor layer SCL1, a second-type semiconductor layer SCL2, and a light-emitting layer LEL, wherein the light-emitting layer LEL is disposed between the first-type semiconductor layer SCL1 and the second-type semiconductor layer SCL2. The first electrode E1 and the second electrode E2 are electrically connected to the first-type semiconductor layer SCL1 and the second-type semiconductor layer SCL2, respectively. The first electrode E1 and the second electrode E2 of the light-emitting element 120 may be bonded to the two bonding pads 105 respectively to achieve electrical connection between the light-emitting element 120 and the substrate 100 .

In this embodiment, the first electrode E1 and second electrode E2 of the light-emitting element 120 may be disposed on the same side of the epitaxial structure layer facing the substrate 100. More specifically, the light-emitting element 120 may be a flip-chip type micro-light-emitting diode. In this embodiment, the light-emitting element 120 has a front light-emitting surface 120es1 facing away from the substrate 100, a side light-emitting surface 120es2 connected to the front light-emitting surface 120es1, and a first edge 120e1, a second edge 120e2, a third edge 120e3, and a fourth edge 120e4 defining the front light-emitting surface 120es1. The side light-emitting surface 120es2 may surround the front light-emitting surface 120es1. The first edge 120e1 and the third edge 120e3 extend in direction X. The second edge 120e2 and the fourth edge 120e4 extend in direction Y. In this embodiment, the length L1 of each of the first edge 120e1 and the third edge 120e3 along direction X is greater than the length L2 of each of the second edge 120e2 and the fourth edge 120e4 along direction Y (as shown in FIG. 4 ).

For example, the display device 10 may further include a pixel definition layer 110 on the substrate surface 100s of the substrate 100. The pixel definition layer 110 has a plurality of openings defining a plurality of pixel areas PA, and these openings expose a plurality of bonding pads 105 on the substrate 100.

To increase the intensity of light emitted from the light-emitting element 120 at the front light-emitting surface 120es1, the display device 10 further includes a baffle structure 140 on the substrate 100. Baffle structure 140 covers the side light-emitting surface 120es2 of the light-emitting element 120. Baffle structure 140 is adapted to reflect light emitted from the light-emitting layer (LEL) of the light-emitting element 120 toward the side light-emitting surface 120es2 back toward the epitaxial structure layer, thereby increasing the chance of light being emitted from the front light-emitting surface 120es1. Baffle structure 140 is made of, for example, white or highly reflective material.

Referring to Figures 2B, 3A, and 3B, the barrier structure 140 has an opening OP1 that overlaps the light-emitting element 120 along direction Z. For example, in this embodiment, the barrier structure 140 has only one opening OP1 in each pixel area PA. This opening OP1 extends in direction Y and overlaps three light-emitting elements 121-123 in the pixel area PA. However, the present invention is not limited to this. In an embodiment (not shown), the barrier structure may have three openings in each pixel area PA, overlapping three light-emitting elements 120, respectively, and these three openings are spaced apart from each other.

Specifically, the baffle structure 140 includes a first baffle 141 and a second baffle 142. The first baffle 141 is disposed on the pixel definition layer 110, with a passivation layer 115 optionally disposed therebetween. The first baffle 141 surrounds the light-emitting element 120 and covers the lateral light-emitting surface 120es2 of the light-emitting element 120. The second baffle 142 is disposed on the first baffle 141 and does not overlap with the plurality of light-emitting elements 120 along the direction Z. More specifically, the second baffles 142 are disposed on opposite sides of the light emitting element 120 along direction X (ie, the first direction), but are not disposed on opposite sides of the light emitting element 120 along direction Y (ie, the second direction).

In this embodiment, a light-transmitting layer 160 is disposed between the first baffle 141 and the second baffle 142. The material of the light-transmitting layer 160 may include, but is not limited to, a transparent photoresist material. Furthermore, the second baffle 142 defines an opening OP1 of the baffle structure 140. A scattering layer 165 may be disposed within the opening OP1. The scattering layer 165 may be, for example, made of a transparent photoresist material doped with scattering particles. It should be noted that the provision of the scattering layer 165 can further improve color shift caused by positional misalignment when the light-emitting element 120 is bonded to the substrate 100 at wide viewing angles in the display device 10. However, the present invention is not limited to this embodiment. In other embodiments, the scattering layer 165 may be replaced by another light-transmitting layer, and the material of the other light-transmitting layer and the light-transmitting layer 160 may be selectively the same.

From another perspective, in this embodiment, the barrier structure 140 includes a first portion 140p1 and a second portion 140p2. The first portion 140p1 is disposed opposite the first edge 120e1 and the third edge 120e3 of the light-emitting element 120 along the direction Y. The second portion 140p2 is disposed opposite the second edge 120e2 and the fourth edge 120e4 of the light-emitting element 120 along the direction X. In other words, the first portion 140p1 of the barrier structure 140 is located on opposite sides of the light-emitting element 120 along the direction Y and does not overlap with the light-emitting element 120 along the direction X. The second portion 140p2 of the blocking structure 140 is located on two opposite sides of the light emitting element 120 along the direction X and does not overlap with the light emitting element 120 along the direction Y.

More specifically, the portion of the first baffle 141 of the baffle structure 140 that overlaps with the light-emitting element 120 along the direction Y constitutes a first portion 140p1 of the baffle structure 140 (as shown in FIG3B ), and the portions of the first baffle 141 and the second baffle 142 of the baffle structure 140 that overlap with the light-emitting element 120 along the direction X constitute a second portion 140p2 of the baffle structure 140 (as shown in FIG3A ).

In this embodiment, the first portion 140p1 and the second portion 140p2 of the baffle structure 140 respectively have a first top surface 140ts1 and a second top surface 140ts2 facing away from the substrate 100. The top surfaces of these portions are, for example, the surfaces of the baffle structure 140 farthest from the substrate surface 100s. In other words, the portion of the first baffle 141 that constitutes the first portion 140p1 of the baffle structure 140 is defined as the first top surface 140ts1 on the side facing away from the substrate 100, while the portion of the second baffle 142 that constitutes the second portion 140p2 of the baffle structure 140 is defined as the second top surface 140ts2 on the side facing away from the substrate 100.

Of particular note, in the normal direction (e.g., direction Z) of the substrate surface 100s, the first top surface 140ts1 of the barrier structure 140 is lower than the front light-emitting surface 120es1 of the light-emitting element 120, but higher than the light-emitting layer (LEL) of the light-emitting element 120. The second top surface 140ts2 of the barrier structure 140 is higher than the front light-emitting surface 120es1 of the light-emitting element 120. That is, the height of the second portion 140p2 of the second edge 120e2 and the fourth edge 120e4 of the blocking structure 140 facing the light-emitting element 120 relative to the substrate surface 100s is higher than the front light-emitting surface 120es1 of the light-emitting element 120 (as shown in FIG3A ), while the height of the first portion 140p1 of the first edge 120e1 and the third edge 120e3 of the blocking structure 140 facing the light-emitting element 120 and directly covering the lateral light-emitting surface 120es2 relative to the substrate surface 100s is lower than the front light-emitting surface 120es1 of the light-emitting element 120 (as shown in FIG3B ).

3A, 3B, and 4, the light-shielding structure 170 is further described as being disposed on the baffle structure 140 and including a first light-shielding layer 171 and a second light-shielding layer 172. The first light-shielding layer 171 is disposed on the first baffle 141 and overlaps the first portion 140p1 of the baffle structure 140 along the direction Z. The second light-shielding layer 172 is disposed on the second baffle 142 and overlaps the second portion 140p2 of the baffle structure 140 along the direction Z.

In this embodiment, the first light-shielding layer 171 and the second light-shielding layer 172 have heights H1 and H2, respectively, relative to the substrate surface 100s, with height H2 being greater than height H1. Specifically, the height H1 of the first light-shielding layer 171 disposed on the first portion 140p1 of the baffle structure 140 is lower than the height H2 of the second light-shielding layer 172 disposed on the second portion 140p2 of the baffle structure 140. In other words, the height H1 of the portion of the light-shielding structure 170 facing the first edge 120e1 and the third edge 120e3 of the light-emitting element 120 along the direction Y is lower than the height H2 of the other portion of the light-shielding structure 170 facing the second edge 120e2 and the fourth edge 120e4 of the light-emitting element 120 along the direction X.

Since the display device is susceptible to color shift at wide viewing angles due to positional shift of the light-emitting element 120 when bonded to the substrate 100, and since the length L1 of the light-emitting element 120 along the X direction is greater than its length L2 along the Y direction, the color shift at wide viewing angles caused by the positional shift of the light-emitting element 120 in the Y direction is greater than the color shift at wide viewing angles caused by the positional shift of the light-emitting element 120 in the X direction.

Therefore, by positioning the second top surface 140ts2 of the second portion 140p2 of the baffle structure 140 higher than the front light-emitting surface 120es1 of the light-emitting element 120, and positioning the first top surface 140ts1 of the first portion 140p1 of the baffle structure 140 lower than the front light-emitting surface 120es1 of the light-emitting element 120, this significantly improves the light-extraction efficiency of the light-emitting element 120 and also suppresses color shift caused by positional misalignment when the light-emitting element 120 is bonded to the substrate 100 at wide viewing angles. In other words, both light-extraction efficiency and color performance of the display device 10 are maintained.

In this embodiment, the first light-shielding layer 171 has a light-shielding edge 171e1 and a light-shielding edge 171e2 that define an opening OP2 and extend in the direction X, while the second light-shielding layer 172 has a light-shielding edge 172e1 and a light-shielding edge 172e2 that define an opening OP2 and extend in the direction Y. It is particularly noteworthy that the distance d1 between the light-shielding edge 171e1 and the first edge 120e1 along the direction Y, and the distance d3 between the light-shielding edge 171e2 and the third edge 120e3 along the direction Y, are greater than the distance d2 between the light-shielding edge 172e1 and the second edge 120e2 along the direction X, and the distance d4 between the light-shielding edge 172e2 and the fourth edge 120e4 along the direction X. From another perspective, the difference between the length L4 of the opening OP2 of the light-shielding structure 170 along the direction Y and the length L2 of the light-emitting element 120 along the direction Y is greater than the difference between the length L3 of the opening OP2 of the light-shielding structure 170 along the direction X and the length L1 of the light-emitting element 120 along the direction X. Consequently, the large chromatic aberration in the viewing angle of the display device 10 caused by positional misalignment when the light-emitting element 120 is bonded to the substrate 100 can be further reduced.

In this embodiment, the display device 10 may further include an encapsulation layer 180 covering the light shielding structure 170 and the scattering layer 165. The material of the encapsulation layer 180 may include polydimethylsiloxane (PDMS), for example.

The following is an exemplary description of a method for manufacturing the display device 10.

Referring to Figures 5A and 5B , a bonding process is first performed to bond multiple light-emitting elements 120 to substrate 100. After bonding these light-emitting elements 120 to substrate 100, a first barrier material layer 141M is formed on substrate 100. This first barrier material layer 141M covers the front light-emitting surface 120es1 and the side light-emitting surface 120es2 of the light-emitting element 120, the bonding pad 105, and the pixel definition layer 110.

Next, the first baffle material layer 141M undergoes an exposure and development process to form the first baffle 141 of the baffle structure 140, as shown in Figures 5B and 6B. It should be noted that the exposure process for the first baffle material layer 141M employs, for example, a weak exposure method. Therefore, after the development process, the portion of the first baffle material layer 141M above the front light-emitting surface 120es1 of the light-emitting element 120 is removed, leaving only the portion covering the lateral light-emitting surface 120es2.

Referring to Figures 5C and 6C , after the first baffle 141 is completed, a light-transmitting material layer 160M is formed to cover the first baffle 141 and the front light-emitting surface 120es1 of the light-emitting element 120. An exposure and development process is performed on the light-transmitting material layer 160M to form the light-transmitting layer 160, as shown in Figures 5D and 6D . Next, a first light-shielding material layer 171M is formed on the light-transmitting layer 160 to cover the light-transmitting layer 160 and the first baffle 141, as shown in Figures 5E and 6E .

An exposure and development process is performed on the first light-shielding material layer 171M to form the first light-shielding layer 171, as shown in Figures 5F and 6F. After the development process, the first light-shielding layer 171 has an opening OP2a, and the light-transmitting layer 160 is positioned within the opening OP2a. Referring to Figures 5G and 6G, a second barrier material layer 142M is formed on the first light-shielding layer 171. An exposure and development process is performed on the second barrier material layer 142M to form the second barrier 142 of the barrier structure 140, as shown in Figures 5H and 6H. The second barrier 142 has an opening OP1 that overlaps with the front light-emitting surface 120es1 of the light-emitting element 120 along the direction Z.

Referring to Figures 5I and 6I , after the second barrier 142 is completed, a scattering layer 165 is formed to fill the opening OP1 of the second barrier 142. Next, a second light-shielding material layer 172M is formed on the scattering layer 165 and subjected to an exposure and development process to form a second light-shielding layer 172, as shown in Figures 5J and 6J . After the development process, the second light-shielding layer 172 has an opening OP2b.

Specifically, in the normal direction (e.g., direction Z) of the substrate surface 100s, the overlapping portion of the opening OP2a of the first light-shielding layer 171 and the opening OP2b of the second light-shielding layer 172 defines the opening OP2 of the light-shielding structure 170 in FIG2A . Subsequently, an encapsulation layer 180 is formed on the second light-shielding layer 172 to cover the scattering layer 165 and the second light-shielding layer 172, as shown in FIG3A and FIG3B . This completes the fabrication of the display device 10 of this embodiment.

The following will list some other embodiments to illustrate the present invention in detail, wherein the same components will be marked with the same symbols, and the description of the same technical content will be omitted. For the omitted parts, please refer to the above embodiments and will not be repeated below.

FIG7 is a schematic cross-sectional view of a display device according to a second embodiment of the present invention. Referring to FIG7 , compared to the display device 10 of FIG3A , the display device 10A of this embodiment further includes a color conversion layer 168. For example, in this embodiment, the color conversion layer 168 may be disposed within the opening OP1 of the baffle structure 140 and between the scattering layer 165 and the light-transmitting layer 160, but this is not limiting. In a variant embodiment, the scattering layer 165 may be disposed between the color conversion layer 168 and the light-transmitting layer 160. The provision of the color conversion layer 168 increases the flexibility of selecting the light-emitting element 120 and enhances the color performance of the display device 10A.

Figure 8 is a schematic cross-sectional view of a display device according to a third embodiment of the present invention. Referring to Figure 8 , compared to the display device 10 shown in Figure 3A , the display device 10B of this embodiment further includes a light filter layer 190. In this embodiment, light filter layer 190 can be disposed within opening OP2 of the light-shielding structure 170. The provision of light filter layer 190 further enhances the color rendering of the display device 10B.

Figure 9 is a schematic cross-sectional view of a display device according to a fourth embodiment of the present invention. Referring to Figure 9 , compared to the display device 10 shown in Figure 3A , the display device 10C of this embodiment further includes a color conversion layer 168 and a light filter layer 190. In this embodiment, the light filter layer 190 can be disposed within the opening OP2 of the light shielding structure 170, and the color conversion layer 168 can be disposed within the opening OP1 of the baffle structure 140, and between the scattering layer 165 and the light-transmitting layer 160, but this is not limiting. The provision of the light filter layer 190 and the color conversion layer 168 further enhances the color performance of the display device 10C. In addition, the provision of the color conversion layer 168 can also increase the flexibility of the light-emitting element 120.

Fig. 10 is a schematic cross-sectional view of a display device according to a fifth embodiment of the present invention. Fig. 11 is a schematic cross-sectional view of a display device according to a sixth embodiment of the present invention. Fig. 12 is a schematic cross-sectional view of a display device according to a seventh embodiment of the present invention.

Referring to FIG. 10 , compared to the display device 10 in FIG. 3A , the display device 10D of this embodiment further includes a lens structure 195. Lens structure 195 can be disposed within opening OP2 of the light-shielding structure 170 and covered by the encapsulation layer 180. For example, in this embodiment, lens structure 195 can be a Fresnel lens with collimating, light-collecting, and high gain at normal viewing angles.

However, the present invention is not limited thereto. In the display device 10E of FIG11 , the lens structure 195A may be a lens array. For example, the lens array includes a plurality of microlenses, and these microlenses may be arranged in multiple rows and columns along directions X and Y, but the present invention is not limited thereto. In another modified embodiment of FIG11 , the lens structure may include a plurality of micro-columnar lenses, and these micro-columnar lenses may be arranged along direction X and extend in direction Y. In the display device 10F of FIG12 , the lens structure 195B may be a single lens with a flat top.

It should be noted that the lens structures in Figures 10 to 12 are for exemplary purposes only, and the present invention is not limited to the contents disclosed in the figures. In other embodiments, the configuration and distribution of the lens structure can be adjusted according to the actual light output requirements of the display device.

In summary, in a display device according to one embodiment of the present invention, a light-emitting element disposed on a surface of a substrate has a first edge and a second edge defining a light-emitting surface and extending in directions intersecting with each other, and the length of the first edge is greater than the length of the second edge. A baffle structure disposed around the light-emitting element has a first portion and a second portion disposed opposite the first edge and the second edge of the light-emitting element, respectively. Because the second top surface of the second portion of the baffle structure is higher than the light-emitting surface of the light-emitting element, the light-emitting efficiency of the light-emitting element can be effectively improved. On the other hand, by making the first top surface of the first portion of the baffle structure lower than the light-emitting surface of the light-emitting element, the large viewing angle deviation of the display device caused by the positional offset when the light-emitting element is bonded to the substrate can be significantly improved.

10, 10A, 10B, 10C, 10D, 10E, 10F: Display device 100: Substrate 100s: Substrate surface 105: Bonding pad 110: Pixel definition layer 115: Passivation layer 120, 121, 122, 123: Light-emitting element 120e1: First edge 120e2: Second edge 120e3: Third edge 120e4: Fourth edge 120es1: Front light-emitting surface 120es2: Side light-emitting surface 140: Baffle structure 140p1: First portion 140p2: Second portion 140ts1: First top surface 140ts2: Second top surface 141: First baffle 141M: First baffle material layer 142: Second baffle 142M: Second baffle material layer 160: Transparent layer 160M: Transparent material layer 165: Scattering layer 168: Color conversion layer 170: Light-shielding structure 171: First light-shielding layer 171M: First light-shielding material layer 172: Second light-shielding layer 172M: Second light-shielding material layer 171e1, 171e2, 172e1, 172e2: Light-shielding edges 180: Encapsulation layer 190: Filter layer 195, 195A, 195B: Lens structure d1-d4: Distance E1: First electrode E2: Second electrode H1, H2: Height L1-L4: Length LEL: Light-emitting layer OP1, OP2, OP2a, OP2b: Openings PA: Pixel area SCL1: First type semiconductor layer SCL2: Second type semiconductor layer TA: Transparent area X, Y, Z: Directions A-A', B-B': Section lines

Figure 1 is a schematic front view of a display device according to a first embodiment of the present invention. Figures 2A and 2B are enlarged schematic views of a portion of the display device of Figure 1. Figures 3A and 3B are schematic cross-sectional views of the display device of Figure 2A. Figure 4 is an enlarged schematic view of a portion of the display device of Figure 2A. Figures 5A to 5J and 6A to 6J are schematic cross-sectional views illustrating the manufacturing process of the display device of Figures 3A and 3B. Figure 7 is a schematic cross-sectional view of a display device according to a second embodiment of the present invention. Figure 8 is a schematic cross-sectional view of a display device according to a third embodiment of the present invention. Figure 9 is a schematic cross-sectional view of a display device according to a fourth embodiment of the present invention. Figure 10 is a schematic cross-sectional view of a display device according to a fifth embodiment of the present invention. Figure 11 is a schematic cross-sectional view of a display device according to a sixth embodiment of the present invention. Figure 12 is a schematic cross-sectional view of a display device according to a seventh embodiment of the present invention.

10: Display device

100:Substrate

100s:Substrate surface

105:Joint pad

110: Pixel Definition Layer

115: Passivation layer

120: Light-emitting element

120e2: Second Edge

120e4: The Fourth Edge

120es1: Forward light-emitting surface

120es2: Side light-emitting surface

140: retaining wall structure

140p2: Part 2

140ts2: Second top

141: The First Barrier

142: Second barrier

160: Translucent layer

165: Scattering layer

170: Shading structure

172: Second light-shielding layer

172e1, 172e2: Shading edge

180: Packaging layer

E1: First electrode

E2: Second electrode

H2: Height

LEL: Luminescent layer

OP1: Opening

SCL1: Type I semiconductor layer

SCL2: Type II semiconductor layer

X, Y, Z: Direction

A-A’: section line

Claims (12)

A display device comprises: a substrate; a light-emitting element bonded to the substrate, the light-emitting element having a front light-emitting surface facing away from the substrate and a first edge and a second edge defining the front light-emitting surface, the first edge and the second edge extending in a first direction and a second direction, respectively, the length of the first edge along the first direction being greater than the length of the second edge along the second direction, the first direction and the second direction being parallel to a substrate surface of the substrate and intersecting with each other; and A baffle structure is disposed on the substrate and surrounds the light-emitting element. The baffle structure has a first portion and a second portion. The first portion is disposed opposite the first edge of the light-emitting element along the second direction, and the second portion is disposed opposite the second edge of the light-emitting element along the first direction. The first portion and the second portion of the baffle structure respectively have a first top surface and a second top surface facing away from the substrate. In a direction normal to the substrate surface, the first top surface is lower than the front light-emitting surface of the light-emitting element, and the second top surface is higher than the front light-emitting surface of the light-emitting element. The display device of claim 1 further comprises: A light-shielding structure disposed on the baffle structure, wherein the baffle structure further comprises a first opening overlapping the light-emitting element, and the light-shielding structure further comprises a second opening overlapping the first opening. The display device of claim 2, wherein the light-shielding structure comprises: a first light-shielding layer disposed on and overlapping the first portion of the baffle structure; and a second light-shielding layer disposed on and overlapping the second portion of the baffle structure, wherein the first light-shielding layer and the second light-shielding layer respectively have a first height and a second height relative to the substrate surface, and the second height is greater than the first height. A display device as described in claim 2, wherein the shading structure further has a first shading edge and a second shading edge defining the second opening, the first shading edge and the second shading edge extend in the first direction and the second direction respectively, and the distance between the first shading edge and the first edge along the second direction is greater than the distance between the second shading edge and the second edge along the first direction. A display device as described in claim 2, wherein the light-emitting element has a first length and a second length along the first direction and the second direction, respectively, and the second opening of the shading structure has a third length and a fourth length along the first direction and the second direction, respectively, the first length is greater than the second length, the third length is greater than the first length, the fourth length is greater than the second length, and the difference between the fourth length and the second length is greater than the difference between the third length and the first length. The display device of claim 1, wherein the baffle structure comprises: a first baffle disposed around the light-emitting element and covering a lateral light-emitting surface of the light-emitting element; and a second baffle disposed on the first baffle and located on opposite sides of the light-emitting element along the first direction, wherein the first baffle has the first top surface, the second baffle has the second top surface, and in a direction normal to the substrate surface, the second baffle does not overlap with the first top surface and the forward light-emitting surface. The display device of claim 6 further comprises: A light-transmitting layer disposed between the first baffle and the second baffle. A display device as described in claim 1, wherein the light-emitting element includes a first type semiconductor layer, a light-emitting layer and a second type semiconductor layer stacked in sequence on the surface of the substrate, the second type semiconductor layer is provided with the forward light-emitting surface on the side opposite to the substrate, and in the normal direction of the substrate surface, the first top surface of the first part of the baffle structure is higher than the light-emitting layer. The display device as described in claim 1, wherein the baffle structure further has a first opening overlapping the light-emitting element, the first opening overlaps the forward light-emitting surface of the light-emitting element, and a scattering layer is disposed in the first opening. The display device as described in claim 9, wherein a color conversion layer is further provided in the first opening. The display device of claim 9 further comprises: A light-shielding structure disposed on the baffle structure and having a second opening overlapping the first opening, wherein a light filter layer is disposed within the second opening. The display device of claim 9 further comprises: A light-shielding structure disposed on the baffle structure and having a second opening overlapping the first opening, wherein a lens structure is disposed within the second opening.