TWI847721B - Light emitting diode display device and its light emitting diode display unit - Google Patents

Abstract

The present invention provides an LED display unit, which includes a circuit board, a plurality of LED elements and a diffusion sheet. The plurality of LED elements are arranged at intervals on the circuit board, and each LED element corresponds to a central line. The diffusion sheet is arranged on the plurality of LED elements. The diffusion sheet defines a reference line and includes a plurality of microstructures. The location of any microstructure corresponds to the location of one of the plurality of LED elements. Each microstructure at least includes a main light-transmitting area and two raised areas, and the main light-transmitting area is located between the two raised areas. Any one of the microstructures changes A minimum distance between the main light-transmitting area of any microstructure and the center line of the LED element corresponding to the microstructure is changed according to a distance between the microstructure and the reference line.

Description

LED display device and LED display unit thereof

The present invention relates to a display unit, in particular to an LED display unit using a filter having a microstructure. The present invention also includes an LED display device formed by the LED display unit.

LED display devices have many advantages over traditional LCD display devices, such as lower energy consumption, smaller size and better picture presentation, etc. Therefore, LED display devices have gradually become the mainstream in the market in recent years.

Conventional LED display devices can provide a multi-angle viewing effect, so that when viewers view the conventional LED display device from different angles, the images they view are all the same. However, this design also causes conventional LED display devices to be somewhat insufficient in the functional application of visual display (such as the display of three-dimensional images or multiple image changes). In addition, conventional LED display devices often produce differences in screen brightness and chromaticity for the same image due to changes in viewing angles, which easily produces a poor visual experience for viewers.

Therefore, how to design a display device to improve the above-mentioned problems is indeed a topic worthy of study.

The purpose of the present invention is to provide an LED display unit using a filter having a microstructure, so that viewers can see different images at different viewing angles.

Another object of the present invention is to provide an LED display device that solves the brightness and chromaticity differences caused by different viewing angles.

Another object of the present invention is to provide an LED display device that can achieve the same illumination on a specified plane in space.

To achieve the above-mentioned purpose, the LED display unit of the present invention includes a circuit board, a plurality of LED elements and a diffusion sheet. The plurality of LED elements are arranged on the circuit board at intervals, and each LED element corresponds to a center line. The diffusion sheet is arranged on the plurality of LED elements, and the diffusion sheet defines a baseline and includes a plurality of microstructures. The setting position of any microstructure corresponds to the setting position of one of the plurality of LED elements. Each microstructure includes at least a main light-transmitting area and two raised areas, and the main light-transmitting area is located between the two raised areas. Any of the microstructures changes the minimum distance between the main light-transmitting area and the center line of the LED element corresponding to the microstructure according to the distance from the baseline.

In one embodiment of the present invention, the farther any microstructure is from the reference line, the greater the minimum distance between the main light-transmitting area and the center line of the LED element corresponding to the microstructure.

In one embodiment of the present invention, each microstructure defines a coverage area, and each LED element is located within the coverage area of the corresponding microstructure.

In one embodiment of the present invention, the coverage area is a rectangular area.

In one embodiment of the present invention, the main light-transmitting area forms a flat structure, and the height of the flat structure is lower than the height of each protruding area.

In one embodiment of the present invention, each raised area includes at least one pyramidal structure.

In one embodiment of the present invention, at least one conical structure includes a first conical structure, a second conical structure and a third conical structure which are continuous in structure, and the widths of the first conical structure, the second conical structure and the third conical structure are sequentially increased or sequentially decreased.

In one embodiment of the present invention, the width of the main light-transmitting area decreases as the distance between the microstructure and the reference line increases.

In one embodiment of the present invention, the plurality of microstructures are divided into a plurality of first microstructures and a plurality of second microstructures, the main light-transmitting region of each first microstructure is aligned with the reference line, and the two raised regions of each first microstructure are structurally symmetrical.

In one embodiment of the present invention, each second microstructure is far away from the reference line, and the two raised areas of each second microstructure are in a circular structure separated by the main light-transmitting area.

In one embodiment of the present invention, each second microstructure further includes a secondary light-transmitting region, and one of the two raised regions is located between the primary light-transmitting region and the secondary light-transmitting region.

The present invention further includes an LED display device. The LED display device includes a plurality of LED display units as described above. Any LED display unit in the plurality of LED display units is adjacent to another adjacent LED display unit.

Accordingly, the LED display unit of the present invention utilizes a plurality of microstructures of a diffusion sheet to correspond to a plurality of LED elements, so that each LED element can emit light in different directions through the corresponding microstructure design, so that the viewer can see different images at different angles, or can see different images with both eyes, and can maintain sufficient brightness and chromaticity of the image presentation, so as to improve the functional applicability of the LED display unit of the present invention and meet different design requirements.

Since the various aspects and embodiments are only exemplary and non-restrictive, after reading this specification, a person with ordinary knowledge may also have other aspects and embodiments without departing from the scope of the invention. According to the following detailed description and patent application scope, the features and advantages of these embodiments will be more prominent.

In this document, "a" or "an" is used to describe the elements and components described herein. This is only for convenience of explanation and to provide a general meaning for the scope of the present invention. Therefore, unless it is obvious that it is otherwise intended, such description should be understood to include one or at least one, and the singular also includes the plural.

As used herein, the terms "include," "have," or any other similar terms are intended to cover a non-exclusive inclusion. For example, a component or structure having plural elements is not limited to those elements listed herein but may include other elements that are not expressly listed but are generally inherent to the component or structure.

Please refer to Figures 1 and 2, where Figure 1 is a side view of the LED display unit of the present invention, and Figure 2 is a front view of the LED display unit of the present invention. As shown in Figures 1 and 2, the LED display unit 1 of the present invention includes a circuit board 10, a plurality of LED elements 20 and a diffusion sheet 30. The plurality of LED elements 20 are arranged on one side of the circuit board 10 at intervals, and the other opposite side of the circuit board 10 can be arranged on a base or a frame (not shown). Each LED element 20 corresponds to a center line C, and the center line C passes through the center point of the LED element 20. The diffusion sheet 30 is arranged on the plurality of LED elements 20. The diffusion sheet 30 can be stacked and fixed on the circuit board 10 by additionally provided snap-fit parts or other fastening components, or the diffusion sheet 30 and the circuit board 10 can be provided with a snap-fit or fixed effect by the aforementioned base or frame; and the plurality of LED elements 20 are sandwiched between the circuit board 10 and the diffusion sheet 30.

In the present invention, the diffusion sheet 30 defines a reference line B, and the diffusion sheet 30 can be divided into two equal parts, left and right, based on the reference line B. The diffusion sheet 30 includes a plurality of microstructures 31. The location of any microstructure 31 corresponds to the location of one of the plurality of LED elements 20, that is, a corresponding microstructure 31 is stacked on top of each LED element 20. In one embodiment of the present invention, each microstructure 31 can define a coverage area A, and the coverage area A can be regarded as the boundary of the microstructure 31. Each LED element 20 is located within the coverage area A of the corresponding microstructure 31. The aforementioned coverage area A may present different shapes according to the design of the microstructure 31. For example, in the present invention, the coverage area A is illustrated by taking a rectangular area as an example, but the coverage area may also present a circular area, a polygonal area or an area of other shapes.

In the following example, the plurality of LED elements 20 are arranged in a 5×5 matrix on the circuit board 10, and the plurality of microstructures 31 on the diffusion sheet 30 are also arranged in a 5×5 matrix to match the plurality of LED elements 20, but the present invention is not limited thereto, and the number and arrangement of the LED elements 20 and the corresponding microstructures 31 can be adjusted according to design requirements (for example, a 3×3, 7×4 or other matrix arrangement or non-matrix arrangement). The number of the plurality of microstructures 31 arranged in any horizontal row (i.e., along the line segment N-N1 or other horizontal row positions parallel to the line segment N-N1) is not less than 3.

In the present invention, each microstructure 31 of the LED display unit includes at least a main light-transmitting area 311 and two raised areas 312, and the main light-transmitting area 311 is located between the two raised areas 312. The main light-transmitting area 311 forms a flat structure, and the main light-transmitting area 311 mainly allows the light emitted by the corresponding LED element 20 to pass through in a straight line without obvious refraction. The height of the main light-transmitting area 311 is lower than the height of each raised area 312. Each raised area 312 forms a three-dimensional structure, and the direction of light emission is limited by the combination of the main light-transmitting area 311 and the two raised areas 312. In terms of structural configuration, the center line C corresponding to each LED element 20 will pass through the center point of the corresponding microstructure 31, but the present invention is not limited to this.

As shown in FIG. 1 and FIG. 2 , as the distance between any microstructure 31 and the reference line B varies, the location of the main light-transmitting area 311 and the two raised areas 312 of the microstructure 31 will also change accordingly. In the design of the present invention, any microstructure 31 will change the distance between its main light-transmitting area 311 and the center line C of the LED element 20 corresponding to the microstructure 31 according to the distance from the reference line B (for example, the straight line distance along the line segment N-N1 in FIG. 2 ). In one embodiment of the present invention, the farther any microstructure 31 is from the reference line B, the greater the minimum distance between the main light-transmitting area 311 and the center line C of the LED element 20 corresponding to the microstructure 31.

In addition, in one embodiment of the present invention, the width of the main light-transmitting area 311 (e.g., the straight line distance along the line segment N-N1 in FIG. 2 ) decreases as the distance between the microstructure 30 and the reference line B increases. In other words, the farther any microstructure 31 is from the reference line B, the smaller the width of the main light-transmitting area 311 becomes.

Please refer to Figures 1 to 4 together, wherein Figure 3 is a schematic diagram of the first microstructure of the LED display unit of the present invention after the cross-section is taken along the line segment N-N1 in Figure 2, and Figure 4 is a schematic diagram of the second microstructure of the LED display unit of the present invention after the cross-section is taken along the line segment N-N1 in Figure 2. As shown in FIG. 2 , in one embodiment of the present invention, the plurality of microstructures 31 in FIG. 1 can be divided into a plurality of first microstructures 31 a within a dotted block G1 ( FIG. 3 shows any first microstructure 31 a in the vertical row of the dotted block G1 in FIG. 2 ) and a plurality of second microstructures 31 b within a dotted block G2 ( FIG. 4 shows any second microstructure 31 b in the vertical row of the dotted block G2 in FIG. 2 farthest from the baseline B of the diffusion sheet 30 ). That is, the plurality of first microstructures 31a are disposed corresponding to the reference line B of the diffusion sheet 30, and the plurality of second microstructures 31b are symmetrically disposed on both sides of the reference line B of the diffusion sheet 30 (or the plurality of first microstructures 31a).

As shown in FIG. 3 , each first microstructure 31a of the LED display unit of the present invention includes a main light-transmitting area 311a and two raised areas 312a, and the main light-transmitting area 311a is located between the two raised areas 312a. In terms of structural configuration, the center line C corresponding to the LED element 20 will pass through the center point of the corresponding first microstructure 31a and also pass through the main light-transmitting area 311a. Therefore, the light emitted by the LED element 20 is limited by the two raised areas 312a, so that the light remains roughly vertical through the main light-transmitting area 311 without affecting the brightness or illumination of the light.

In one embodiment of the present invention, each raised area 312a includes a first cone structure 3121a, a second cone structure 3122a and a third cone structure 3123a which are continuous in structure, and the widths of the first cone structure 3121a, the second cone structure 3122a and the third cone structure 3123a increase or decrease in sequence as they are away from the center line C.

For example, FIG3 shows any first microstructure 31a in the vertical row of the dotted line area G1 in FIG2. The main light-transmitting area 311a of the first microstructure 31a is aligned with the reference line B, and the two raised areas 312a of the first microstructure 31a are structurally symmetrical based on the reference line B. For example, in FIG3, the two raised areas 312a located on both sides of the reference line B respectively present a continuous structure arranged in the order of the first pyramidal structure 3121a, the second pyramidal structure 3122a, and the third pyramidal structure 3123a. Therefore, all LED elements 20 corresponding to the first microstructure 31a can emit light perpendicularly through the main light-transmitting area 311a of the first microstructure 31a (for example, the main light-transmitting area 311a is directed toward the arrow direction above the figure) and emit it in a concentrated manner, and the light passing through each protrusion area 312a is refracted and dispersed by the three-dimensional structural design. Accordingly, the viewer standing in front of the LED display unit of the present invention will mainly focus on the lighting effect with the maximum brightness or illumination presented by the main light-transmitting area 311a of the first microstructure 31a.

As shown in FIG. 2 and FIG. 4 , each second microstructure 31b of the LED display unit of the present invention includes a main light-transmitting area 311b and two raised areas 312b, and the main light-transmitting area 311b is located between the two raised areas 312b. In terms of structural configuration, the center line C corresponding to the LED element 20 will not pass through the center point of the corresponding first microstructure 31b, nor will it pass through the main light-transmitting area 311b. The light emitted by the LED element 20 is limited by the two raised areas 312b, so that the light roughly maintains an angle and passes through the main light-transmitting area 311b obliquely, thereby reducing the brightness or illumination of the light.

For example, Fig. 4 shows any second microstructure 31b in the vertical row farthest from the reference line B of the diffusion sheet 30 in the dotted line block G2 of Fig. 2. The main light-transmitting area 311b of the second microstructure 31b is far from the reference line B, and the two raised areas 312b of the second microstructure 31b are cyclic structures separated by the main light-transmitting area 311b. One of the two raised areas 312b presents a continuous structure arranged in the order of the third cone structure 3123b, the second cone structure 3122b and the first cone structure 3121b from the edge of the covered range, and after the two raised areas 312b are separated by the main light-transmitting area 311b, the other raised area 312b also presents a continuous structure arranged in the order of the third cone structure 3123b, the second cone structure 3122b and the first cone structure 3121b from the edge of the main light-transmitting area 311b, so that the two raised areas 312b form a circular structure separated by the main light-transmitting area 311b.

The third conical structure 3123b of one of the two raised areas 312b is aligned with the center line C of the corresponding LED element 20, so that the main light-transmitting area 311b of the second microstructure 31b deviates from the center line C and has a minimum distance from the center line C. Therefore, all LED elements 20 corresponding to the second microstructure 31b in the same row can emit light passing through the main light-transmitting area 311b of the second microstructure 31b at an oblique angle (for example, the main light-transmitting area 311b is directed toward the arrow direction at the upper left of the figure) and emit it in a concentrated manner, while the light passing through each raised area 312b is dispersed by refraction due to the three-dimensional structure design. Accordingly, a viewer standing directly in front of the LED display unit of the present invention will see the main light-transmitting area 311b of the second microstructure 31b presenting a luminous effect with reduced brightness or illumination; while a viewer standing in front of the LED display unit of the present invention at the oblique angle can instead focus on seeing the luminous effect with maximum brightness or illumination presented by the main light-transmitting area 311b of the second microstructure 31b.

As shown in FIG. 2 and FIG. 4 , the plurality of second microstructures 31b are symmetrically arranged on both sides of the base line B (or the plurality of first microstructures 31a) based on the base line B of the diffusion sheet 30. The main light-transmitting area 311b and the two ridges 312b of each second microstructure 31b and the main light-transmitting area 311b and the two ridges 312b of another symmetrical second microstructure 31b also present a mirror-symmetrical structure, that is, when any second microstructure 31b presents the structural configuration of the main light-transmitting area 311b and the two ridges 312b as shown in FIG. 4 , the other second microstructure 31b symmetrical thereto presents the mirror-symmetrical structural configuration of the main light-transmitting area 311b and the two ridges 312b as shown in FIG. 4 (i.e., the opposite structural configuration).

In addition, as shown in Figures 2 to 4, the minimum distance (which should be 0 in this case) between the main light-transmitting area 311a of any first microstructure 31a and the center line C of the LED element 20 corresponding to the first microstructure 31 will be smaller than the minimum distance between the main light-transmitting area 311b of any second microstructure 31b and the center line C of the LED element 20 corresponding to the second microstructure 31b. Moreover, for any second microstructure 31b in the straight row that is farthest from the baseline B of the diffusion sheet 30 in the dotted block G2 of Figure 2, assuming that the minimum distance between its main light-transmitting area 311b and the center line C of the LED element 20 corresponding to the second microstructure 31 is d1, and for any second microstructure 31b in the straight row that is closest to the baseline B of the diffusion sheet 30 in the dotted block G2 of Figure 2, assuming that the minimum distance between its main light-transmitting area 311b and the center line C of the LED element 20 corresponding to the second microstructure 31b is d2, then d2 will be smaller than d1.

Furthermore, the width of the main light-transmitting region 311a of any first microstructure 31a is greater than the width of the main light-transmitting region 311b of any second microstructure 31b. For example, if the width of the main light-transmitting region 311b of any second microstructure 31b in the vertical row farthest from the reference line B of the diffusion sheet 30 in the dotted line block G2 of FIG. 2 is w1, and if the width of the main light-transmitting region 311b of any second microstructure 31b in the vertical row closest to the reference line B of the diffusion sheet 30 in the dotted line block G2 of FIG. 2 is w2, then w2 is greater than w1.

With this design, the present invention can utilize a plurality of LED display units to be spliced in pairs to form an overall display device of the required size. When a viewer stands directly in front of the display device, he or she will mainly see the light rays emitted vertically by all the first microstructures 31a of each LED display unit of the present invention, and the image presented after being combined, while the light rays emitted obliquely by all the second microstructures 31b of each LED display unit of the present invention are not easily seen by the viewer directly in front. As the viewer moves from directly in front of the display device and presents different oblique angles with the display device, he or she will mainly see the light rays emitted obliquely by all the second microstructures 31 of different vertical rows of each LED display unit of the present invention (for the viewer in the oblique front, this is equivalent to seeing the light rays emitted vertically), and the image presented after being combined. Therefore, by changing the angle at which the viewer views the display device, different images can be seen from the display device, and these images can all present sufficient brightness and color.

In addition, since human eyes have parallax due to different distances, the design of the display device described above can enable the viewer's eyes to see different images at the same time, thereby providing the display device with an effect similar to naked-eye 3D images.

Please refer to FIG5 for a schematic diagram of the LED display device of the present invention. As shown in FIG5 , the present invention further includes an LED display device 500. The LED display device 500 includes a plurality of LED display units 1 as described above. Any LED display unit 1 among the plurality of LED display units 1 is adjacent to another adjacent LED display unit 1, so that the plurality of LED display units 1 are assembled into an integral LED display device 500 by splicing them in pairs. The number of the plurality of LED display units 1 included in the LED display device 500 can be adjusted according to design requirements or different sizes. Each LED display unit 1 is an independent module unit corresponding to a single pixel, and the LED display device 500 providing a multi-pixel display is formed by combining a plurality of LED display units 1.

The above embodiments are essentially only for auxiliary explanation and are not intended to limit the embodiments of the application subject or the application or use of such embodiments. In addition, although at least one exemplary embodiment has been proposed in the aforementioned embodiments, it should be understood that the present invention can still exist in a large number of variations. It should also be understood that the embodiments described herein are not intended to limit the scope, use or configuration of the claimed application subject in any way. On the contrary, the aforementioned embodiments will provide a simple guide for those with ordinary knowledge in the field to implement one or more of the embodiments described. Furthermore, various changes can be made to the function and arrangement of the components without departing from the scope defined by the scope of the patent application, and the scope of the patent application includes known equivalents and all foreseeable equivalents at the time of filing the present patent application.

1:LED display unit

10: Circuit board

20:LED components

30: Diffuse tablets

31, 31a, 31b: Microstructure

311, 311a, 311b: main light transmission area

312, 312a, 312b: uplift area

3121a, 3121b: first cone structure

3122a, 3122b: Second cone structure

3123a, 3123b: The third cone structure

A: Coverage

C: Centerline

B: Baseline

500:LED display device

FIG. 1 is a side view of the LED display unit of the present invention. FIG. 2 is a front view of the LED display unit of the present invention. FIG. 3 is a schematic diagram of the first microstructure of the LED display unit of the present invention after the section is taken along the line segment N-N1 in FIG. 2. FIG. 4 is a schematic diagram of the second microstructure of the LED display unit of the present invention after the section is taken along the line segment N-N1 in FIG. 2. FIG. 5 is a schematic diagram of the LED display device of the present invention.

1:LED display unit

10: Circuit board

20:LED components

30: Diffusion film

31: Microstructure

311: Main light transmission area

312: Uplift area

C: Center line

B: Baseline

Claims (11)

An LED display unit includes: a circuit board; a plurality of LED elements arranged on the circuit board at intervals, each of the LED elements corresponding to a center line; and a diffusion sheet arranged on the plurality of LED elements, the diffusion sheet defines a baseline and includes a plurality of microstructures, the arrangement position of any of the microstructures corresponds to the arrangement position of one of the plurality of LED elements, each of the microstructures includes at least a main light-transmitting area and two ridges, and the main light-transmitting area is located between the two ridges; any of the microstructures changes a minimum distance between the main light-transmitting area and the center line of the LED element corresponding to the microstructure according to the distance from the baseline. The LED display unit as described in claim 1, wherein the farther any microstructure is from the baseline, the greater the minimum distance between the main light-transmitting area and the center line of the LED element corresponding to the microstructure. The LED display unit as described in claim 1, wherein each microstructure defines a coverage range, and each LED element is located within the coverage range of the corresponding microstructure. An LED display unit as described in claim 3, wherein the coverage area is a rectangular area. The LED display unit as described in claim 1, wherein the main light-transmitting area forms a flat structure, and the height of the flat structure is lower than the height of each of the raised areas. An LED display unit as described in claim 5, wherein each of the raised areas includes at least one cone-shaped structure. The LED display unit as described in claim 6, wherein the at least one conical structure includes a first conical structure, a second conical structure and a third conical structure in a continuous structure, and the widths of the first conical structure, the second conical structure and the third conical structure increase or decrease in sequence. The LED display unit as described in claim 1, wherein the width of the main light-transmitting area decreases as the distance between the microstructure and the baseline increases. The LED display unit as described in claim 1, wherein the plurality of microstructures are divided into a plurality of first microstructures and a plurality of second microstructures, the main light-transmitting area of each of the first microstructures is aligned with the reference line, and the two raised areas of each of the first microstructures are structurally symmetrical. The LED display unit as described in claim 9, wherein each of the second microstructures is far away from the baseline, and the two raised areas of each of the second microstructures are in a circular structure separated by the main light-transmitting area. An LED display device, comprising: a plurality of LED display units as described in any one of claims 1 to 10, wherein any LED display unit in the plurality of LED display units is adjacent to another adjacent LED display unit.

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