Backlight unit

Abstract

A backlight device includes a printed circuit board, a plurality of light-emitting diode circuits, and a conductive structure. The printed circuit board has a first surface and a second surface opposite to each other. The plurality of light-emitting diode circuits are disposed on the first surface of the printed circuit board, and the light-emitting diode circuits include a first column of light-emitting diode circuits and a second column of light-emitting diode circuits. The conductive structure is disposed on the second surface of the printed circuit board and electrically coupled to the light-emitting diode circuits. The conductive structure includes a first conductor and a plurality of wires. The first conductor is electrically coupled to the first column of light-emitting diode circuits, and a projection on the first surface of the printed circuit board at least covers the first column of light-emitting diode circuits. The wires are electrically coupled to the first conductor, and the impedances of the wires are substantially matched to each other.

Description

Technical Field

[0001] The present invention relates to a backlight device, and more particularly to a backlight device having a conductive structure. Background Art

[0002] Backlight devices are widely used in various electronic products, and a backlight device usually includes a light-emitting diode circuit. In a known light-emitting diode circuit, the layout and routing method of the light-emitting diode circuit (for example, the X-Y line method) may be affected by impedance mismatch, resulting in different power supply signals received by the light-emitting diode circuits at different positions and different light-emitting degrees, thereby causing the problem of uneven brightness of the backlight device. Therefore, how to develop related technologies that can overcome the above problems is an important topic in this field. Summary of the Invention

[0003] An object of the present invention is to provide a backlight device to solve at least one of the above problems.

[0004] One embodiment of the present invention is a backlight device, including a printed circuit board, a plurality of light-emitting diode circuits, and a conductive structure. The printed circuit board has a first surface and a second surface opposite to each other. The plurality of light-emitting diode circuits are disposed on the first surface of the printed circuit board, wherein the plurality of light-emitting diode circuits include a first column of light-emitting diode circuits and a second column of light-emitting diode circuits, and the first column of light-emitting diode circuits and the second column of light-emitting diode circuits are disposed adjacent to each other. The conductive structure is disposed on the second surface of the printed circuit board, electrically coupled to the plurality of light-emitting diode circuits, and used to transmit a supply power to the plurality of light-emitting diode circuits, wherein the conductive structure includes a first conductor and a wire, wherein the first conductor is electrically coupled to the first column of light-emitting diode circuits, and the projection on the first surface of the printed circuit board at least covers the first column of light-emitting diode circuits. A plurality of wires are electrically coupled to the first conductor, and the impedances of the wires are substantially matched to each other.

[0005] Another embodiment of the present invention is a backlight device, including a printed circuit board, multiple columns of light-emitting diode circuits, and a copper-clad structure, wherein the printed circuit board has a first surface and a second surface opposite to each other. Multiple columns of light-emitting diode circuits are disposed on the first surface of the printed circuit board. The copper-clad structure is disposed on the second surface of the printed circuit board and electrically coupled to at least the first column of light-emitting diode circuits in the multiple columns of light-emitting diode circuits, wherein the copper-clad structure includes a first copper-clad layer and a plurality of copper wires, wherein the first copper-clad layer is electrically coupled to the first column of light-emitting diode circuits, and the projection on the first surface of the printed circuit board at least covers the first column of light-emitting diode circuits. A plurality of copper wires are electrically coupled between the first copper-clad layer and the input terminal, and the lengths of the copper wires between the first copper-clad layer and the input terminal are substantially equal to each other.

[0006] The beneficial effects of the present invention are as follows. Through the conductive structure configuration mentioned in the present invention, the wire impedance in the conductive structure is matched, thereby reducing the brightness difference between different light-emitting positions of the backlight device and improving the problem of uneven brightness of the backlight device. Description of the Drawings

[0007] Figure 1 is a schematic diagram of a backlight device shown according to some embodiments.

[0008] Figure 2 is shown according to some embodiments Figure 1 schematic diagram of a partial backlight device.

[0009] Figure 3 is shown according to some embodiments Figure 1 schematic diagram of a partial backlight device.

[0010] Figure 4 is shown according to some embodiments Figure 1 schematic diagram of a partial backlight device.

[0011] Figure 5 is shown according to some embodiments Figure 1 schematic diagram of a partial backlight device.

[0012] Figure 6 is a schematic diagram of a backlight device shown according to some embodiments.

[0013] The reference numerals are as follows:

[0014] 100: Backlight device

[0015] 101: Printed circuit board

[0016] 103: First surface

[0017] 105: Second surface

[0018] 110: Conductive structure

[0019] 120: Light-emitting diode circuit

[0020] 122: First column light-emitting diode circuit

[0021] 124: Second column light-emitting diode circuit

[0022] 126: Third column light-emitting diode circuit

[0023] 150, 151, 152, 153: Unit

[0024] 211: Conductor

[0025] 213: Wire 230: Hole

[0026] 311: Long side 314, 315, 316: Conductors

[0027] 320: Input terminal

[0028] 324, 325, 326: Endpoints<>

[0029] 410: Conductive structure

[0030] 411, 412: Conductors

[0031] 413: Conductors

[0032] 430: Hole

[0033] 450, 451, 452: Units

[0034] 511, 512: Long sides

[0035] 514, 515, 516, 517, 518, 519: Conductors

[0036] 520: Input terminal

[0037] 524, 525, 526, 527, 528, 529: Endpoints

[0038] VLED, VLED1, VLED2, VLED3, VLED4: Power supplies Detailed implementation manners

[0039] In this document, when an element is referred to as "connected" or "coupled", it may mean "electrically connected" or "electrically coupled". "Connected" or "coupled" can also be used to indicate the mutual cooperation or interaction between two or more elements. In addition, although terms such as "first", "second",... are used in this document to describe different elements, these terms are only used to distinguish elements or operations described with the same technical terms. Unless the context clearly indicates otherwise, these terms do not specifically refer to or imply an order or sequence, nor are they used to limit the present invention.

[0040] The terms used herein are for the purpose of describing particular embodiments only and are not limiting. As used herein, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms, including "at least one". "Or" means "and / or". As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It should also be understood that when used in this specification, the terms "comprises" and / or "comprising" specify the presence and / or components of the stated features, regions, wholes, steps, operations, elements, but do not preclude the presence or addition of one or more other features, regions, wholes, steps, operations, elements, components and / or combinations thereof.

[0041] Figure 1 is a schematic diagram of a backlight device 100 shown according to some embodiments. As Figure 1 shown, the backlight device 100 includes a printed circuit board 101, a conductive structure 110, and a plurality of light-emitting diode circuits 120. The printed circuit board 101 has a first surface 103 and a second surface 105 opposite to each other. The light-emitting diode circuits 120 are disposed on the first surface 103 of the printed circuit board 101, and the conductive structure 110 is disposed on the second surface 105 of the printed circuit board 101. The conductive structure 110 is electrically coupled to the light-emitting diode circuits 120 to transmit a supply power VLED to the above-mentioned light-emitting diode circuits 120. It should be noted that, for convenience and clarity of description, Figure 1 only a single light-emitting diode circuit 120 is labeled, but the number thereof is not limited to Figure 1 that labeled. In other words, Figure 1 the number of the conductive structure 110 and the light-emitting diode circuits 120 shown in combination can be more or less, not limited to Figure 1 that shown.

[0042] As Figure 1 shown, in some embodiments, the combination of the light-emitting diode circuits 120 and the conductive structure 110 can be used as a unit 150. One or more units 150 can be disposed on the printed circuit board 101, that is, there can be more or fewer similar units 150 disposed on the printed circuit board 101, and each of the one or more units 150 is electrically coupled to a different supply power. For example, as Figure 1 shown, three units 151 to 153 are respectively electrically coupled to different supply powers. Unit 151 is electrically coupled to VLED1, unit 152 is electrically coupled to VLED2, and unit 153 is electrically coupled to VLED3. Figure 1 What is depicted is only an example and does not limit the present invention.

[0043] As Figure 1 shown, in some embodiments, the light-emitting diode circuits 120 are arranged in rows and columns. The light-emitting diode circuits 120 include a first column of light-emitting diode circuits 122 and a second column of light-emitting diode circuits 124 arranged adjacent to each other. In some embodiments, there can be more or fewer similar arrangements of rows and columns of light-emitting diode circuits 120 on the first surface 103 of the printed circuit board 101. For the sake of concise description, they are not shown in the figure.

[0044] Figure 2 is a schematic diagram of a partial backlight device 100 shown according to some embodiments. As Figure 1 shown Figure 2As shown, the conductive structure 110 includes a first conductor 211 and a plurality of wires 213. The first conductor 211 is electrically coupled to the first column of light-emitting diode circuits 122, and its projection on the first surface 103 of the printed circuit board 101 at least covers the first column of light-emitting diode circuits 122. The above-mentioned wires 213 are electrically coupled to the first conductor 211, and the impedances of the wires 213 are substantially matched to each other.

[0045] In some embodiments, the first conductor 211 and the wires 213 in the conductive structure 110 are used to transmit the supply power VLED to the light-emitting diode circuit 120, and can be composed of suitable conductive materials such as copper, aluminum, silver, etc. In some embodiments, the first conductor 211 and the wires 213 are implemented with copper, but the present invention is not limited thereto.

[0046] In some embodiments, the printed circuit board 101 has a plurality of holes 230, wherein the first conductor 211 electrically couples the first column of light-emitting diode circuits 122 and the second column of light-emitting diode circuits 124 through the above-mentioned holes 230. In some embodiments, as Figure 2 shown, the projection of the first conductor 211 on the first surface 103 of the printed circuit board 101 also covers the holes 230 that electrically couple the first conductor 211 and the second column of light-emitting diode circuits 124.

[0047] Figure 3 is according to some embodiments Figure 1 Schematic diagram of a partial backlight device 100. The wires in the conductive structure 110 include wires 314, 315, and 316, where the wires 314, 315, and 316 correspond to Figure 2 the wires 213 and are electrically coupled to the input terminal 320, and are used to receive the supply power VLED from the input terminal 320. In some embodiments, the wires 314 to 316 are each electrically coupled to different end points of the first conductor 211, where the wire 314 is electrically coupled to the side end point 324 of the first conductor 211, the wire 315 is electrically coupled to the middle end point 325 of the first conductor 211, and the wire 316 is electrically coupled to the side end point 326 of the first conductor 211. In a further embodiment, the wires 314 to 316 are each electrically coupled to different end points of the long side 311 of the first conductor 211. For example, there are side end points 324 and 326 and a middle end point 325 on the long side, which are respectively electrically connected to the wires 314 to 316. It should be noted that for the sake of convenience and clear illustration, Figure 3 only three wires 314 to 316 are marked, but the number thereof is not limited to Figure 3 what is marked. In other words, Figure 3 as shown, the number of the wires 213 in the conductive structure 110 can be three or more, not limited to Figure 3 what is shown.

[0048] AsFigure 3 As shown, in some embodiments, for the first conductor 211, the distance between the side end point 324 and the middle end point 325 is substantially equal to the distance between the side end point 326 and the middle end point 325, that is, the distance between the wire 314 and the wire 315 electrically coupling different end points of the first conductor 211 is substantially equal to the distance between the wire 316 and the wire 315 electrically coupling different end points of the first conductor 211. By arranging the above wires to be substantially equal in length to each other, the impedances of the wires 314 to 316 are matched to each other.

[0049] Referring to Figures 1 to 3 , in some embodiments, on the printed circuit board 101 in the backlight device 100, one or more units 150 composed of the light-emitting diode circuit 120 and the conductive structure 110 are arranged, so that the impedances of the wires 314 to 316 are matched to each other, thereby reducing the overall brightness difference of the backlight device 100 and improving the problem of uneven brightness of the backlight device. Generally speaking, the known layout and routing method of the light-emitting diode circuit and the power supply line (for example, the X-Y line method) will cause the brightness difference between different light-emitting positions of the backlight device to be 40%. Compared with the known layout and routing method (for example, the X-Y line method), the embodiments of the present invention can be used to reduce the overall brightness difference of the backlight device to less than 5%.

[0050] Figure 4 is according to some embodiments Figure 1 schematic diagram of a partial backlight device 100. As Figure 4 shown, the above-mentioned plurality of light-emitting diode circuits 120 further include a third column of light-emitting diode circuits 126 arranged adjacent to the second column of light-emitting diode circuits 124. The conductive structure 410 is arranged and functions similarly to the conductive structure 110 discussed above (refer to Figure 2 ), and is used to transmit the supply power VLED to the above-mentioned light-emitting diode circuit 120. In some embodiments, the conductive structure 410 includes a first conductor 411, a second conductor 412, and a plurality of wires 413 corresponding to the first conductor 211 and the plurality of wires 213 of the conductive structure 110 (refer to Figure 2 ) respectively, wherein the conductor 411 is electrically coupled to the first column of light-emitting diode circuits 122 and the second column of light-emitting diode circuits 124, and the conductor 412 is electrically coupled to the third column of light-emitting diode circuits 126. The projection of the first conductor 411 on the first surface 103 of the printed circuit board 101 at least covers the first column of light-emitting diode circuits 124, and the projection of the second conductor 412 on the first surface 103 of the printed circuit board 101 at least covers the third column of light-emitting diode circuits 126. The above-mentioned wires 413 are electrically coupled to the conductors 411 and 412, and the impedances of the wires 413 are substantially matched to each other.

[0051] In some embodiments, the conductors 411 and 412 and the wire 413 in the conductive structure 410 are used to transmit the supply power VLED to the light-emitting diode circuit 120, and can be composed of suitable conductive materials such as copper, aluminum, silver, etc. In some embodiments, the conductors 411 and 412 and the wire 413 are implemented by copper, but the present invention is not limited to this.

[0052] In some embodiments, the printed circuit board 101 has a plurality of holes 430, wherein the first conductor 411 is electrically coupled to the first row of LED circuits 122 and the second row of LED circuits 124 through the holes 430, and the second conductor 412 is electrically coupled to the third row of LED circuits 126 through the holes 430. In some embodiments, as Figure 4 As shown, the projection of the first conductor 411 on the first surface 103 of the printed circuit board 101 also covers the hole 430 electrically coupling the first conductor 411 and the second row of LED circuits 124 .

[0053] Figure 5 According to some embodiments Figure 1 Schematic diagram of a portion of the backlight device 100. Figure 5 As shown, the conductive wires in the conductive structure 410 include conductive wires 514 to 519, wherein the conductive wires 514 to 519 correspond to Figure 4 Wire 413 is electrically coupled to input terminal 520 and is used to receive a supply power VLED from input terminal 520. In some embodiments, wires 514-516 are each electrically coupled to a different end of first conductor 411, wherein wire 514 is electrically coupled to a side end 524 of first conductor 411, wire 515 is electrically coupled to a middle end 525 of first conductor 411, and wire 516 is electrically coupled to a side end 526 of first conductor 411. Wires 517-519 are each electrically coupled to a different end of second conductor 412, wherein wire 517 is electrically coupled to a side end 527 of second conductor 412, wire 518 is electrically coupled to a middle end 528 of second conductor 412, and wire 519 is electrically coupled to a side end 529 of second conductor 412. In a further embodiment, the wires 514-516 are each electrically coupled to different endpoints of the long side 511 of the first conductor 411, for example, the long side has side endpoints 524 and 526 and a middle endpoint 525, which are electrically connected to the wires 514-516. The wires 517-519 are each electrically coupled to different endpoints of the long side 512 of the second conductor 412, for example, the long side has side endpoints 527 and 529 and a middle endpoint 528, which are electrically connected to the wires 517-519. It should be noted that for the sake of convenience and clarity of description, Figure 5 Only six wires 514 to 519 are marked, but their number is not Figure 5 In other words, Figure 5The number of wires 413 in the conductive structure 410 shown can be six or more, not limited to Figure 5 shown

[0054] As Figure 5 shown, in some embodiments, for the first conductor 411, the distance between the side end point 524 and the middle end point 525 is substantially equal to the distance between the side end point 526 and the middle end point 525, that is, the distance between the wire 514 and the wire 515 electrically coupling different end points of the first conductor 411 is substantially equal to the distance between the wire 516 and the wire 515 electrically coupling different end points of the first conductor 411, and for the second conductor 412, the distance between the side end point 527 and the middle end point 528 is substantially equal to the distance between the side end point 529 and the middle end point 528, that is, the distance between the wire 517 and the wire 518 electrically coupling different end points of the second conductor 412 is substantially equal to the distance between the wire 519 and the wire 518 electrically coupling different end points of the second conductor 412. By arranging the above wires to be substantially equal in length to each other, the impedances of the wires 514 to 519 are matched to each other

[0055] Referring to Figure 1 and Figures 4 to 5 , in some embodiments, the combination of the light-emitting diode circuit 120 and the conductive structure 410 can be used as a unit 450, and one or more units 450 can be arranged on the printed circuit board 101. For example, three units 450 combined by the light-emitting diode circuit 120 and the conductive structure 410 are arranged on the printed circuit board 101, as Figure 1 and Figure 4 shown. In some embodiments, by arranging the above one or more units 450, the impedances of the wires 514 to 519 therein are matched to each other, thereby reducing the overall brightness difference of the backlight device 100 and improving the problem of uneven brightness of the backlight device. In some embodiments, compared with the known layout routing method of the light-emitting diode circuit and the power supply line (for example, the X-Y line method), the embodiments of the present invention can be used to reduce the overall brightness difference of the backlight device 100 to less than 2%

[0056] Figure 6 is a schematic diagram of the backlight device 100 shown according to some embodiments. As Figure 6As shown, the combination of the light-emitting diode circuit 120 and the conductive structure 110 can serve as the unit 150, and the combination of the light-emitting diode circuit 120 and the conductive structure 410 can serve as the unit 450. Two units 151 and 152 and two units 451 and 452 can be simultaneously arranged on the printed circuit board 101. In other words, two units 151 and 152 combined by the light-emitting diode circuit 120 and the conductive structure 110 and two units 451 and 452 combined by the light-emitting diode circuit 120 and the conductive structure 410 are simultaneously arranged on the printed circuit board 101, and the above four units 151, 152, 451, and 452 are electrically connected to the power supplies VLED1, VLED2, VLED3, and VLED4 respectively. In some embodiments, more or fewer similar units 150 and 450 can be simultaneously arranged on the printed circuit board 101. Figure 6 The drawings are only examples and are not intended to limit the present invention.

[0057] In summary, through the configuration of the conductive structure mentioned in the present invention, the wire impedance in the conductive structure is matched, thereby reducing the brightness difference between different light-emitting positions of the backlight device and improving the problem of uneven brightness of the backlight device.

[0058] Although the present invention has been disclosed above in embodiments, it is not intended to limit the present invention. Those skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to that defined by the appended claims.

Claims

1. A backlight device, comprising: A printed circuit board having a first surface and a second surface opposite to each other; A plurality of light-emitting diode circuits disposed on the first surface of the printed circuit board, wherein the plurality of light-emitting diode circuits includes a first column of light-emitting diode circuits and a second column of light-emitting diode circuits, and the first column of light-emitting diode circuits and the second column of light-emitting diode circuits are disposed adjacent to each other; A conductive structure disposed on the second surface of the printed circuit board, electrically coupled to the plurality of light-emitting diode circuits for transmitting a supply power to the plurality of light-emitting diode circuits, wherein the conductive structure includes: A first conductor electrically coupled to the first column of light-emitting diode circuits, and a projection of the first conductor on the first surface of the printed circuit board at least covers the first column of light-emitting diode circuits; And A plurality of wires electrically coupled to the first conductor, wherein the impedances of the plurality of wires are matched to each other.

2. The backlight device according to claim 1, wherein The plurality of wires includes at least one first wire, at least one second wire, and at least one third wire, wherein the at least one first wire, the at least one second wire, and the at least one third wire are electrically coupled to an input terminal and are used for receiving the supply power from the input terminal, the at least one first wire is electrically coupled to a first side end point of the first conductor, the at least one second wire is electrically coupled to a second side end point of the first conductor, the at least one third wire is electrically coupled to a middle end point of the first conductor, and the first side end point, the second side end point, and the middle end point are located on a long side of the first conductor.

3. The backlight device according to claim 2, wherein The plurality of light-emitting diode circuits further includes: A third column of light-emitting diode circuits disposed adjacent to the second column of light-emitting diode circuits; Wherein the conductive structure further includes: A second conductor electrically coupled to the third column of light-emitting diode circuits, and a projection of the second conductor on the first surface of the printed circuit board at least covers the third column of light-emitting diode circuits.

4. The backlight device according to claim 3, wherein The plurality of wires further includes at least one first wire, at least one second wire, and at least one third wire, wherein the at least one first wire, the at least one second wire, and the at least one third wire are electrically coupled to the input terminal and are used for receiving the supply power from the input terminal, the at least one first wire is electrically coupled to a first side end point of the second conductor, the at least one second wire is electrically coupled to a second side end point of the second conductor, the at least one third wire is electrically coupled to a middle end point of the second conductor, and the first side end point, the second side end point, and the middle end point are located on a long side of the second conductor.

5. The backlight device according to claim 1, wherein the printed circuit board has a plurality of holes, the first conductor electrically couples the first column of light-emitting diode circuits and the second column of light-emitting diode circuits through the plurality of holes, and a projection of the first conductor on the first surface of the printed circuit board further covers the plurality of holes.

6. A backlight device, comprising: A printed circuit board having a first surface and a second surface opposite to each other; Multiple column light-emitting diode circuits are disposed on the first surface of the printed circuit board; A copper-clad structure is disposed on the second surface of the printed circuit board and is electrically coupled to at least a first column light-emitting diode circuit among the multiple column light-emitting diode circuits. The copper-clad structure includes: A first copper-clad layer that is electrically coupled to the first column light-emitting diode circuit and, in a projection on the first surface of the printed circuit board, at least covers the first column light-emitting diode circuit; And Multiple copper wires that are electrically coupled between the first copper-clad layer and an input terminal, and lengths of the multiple copper wires between the first copper-clad layer and the input terminal are equal to each other.

7. The backlight device according to claim 6, wherein The multiple copper wires include at least a first copper wire, at least a second copper wire, and at least a third copper wire. The at least a first copper wire is electrically coupled to a first side end point of the first copper-clad layer, the at least a second copper wire is electrically coupled to a second side end point of the first copper-clad layer, the at least a third copper wire is electrically coupled to a middle end point of the first copper-clad layer, and the first side end point, the second side end point, and the middle end point are located on a long side of the first copper-clad layer, and a distance between the first side end point and the middle end point is equal to a distance between the second side end point and the middle end point.

8. The backlight device according to claim 6, wherein A second column light-emitting diode circuit among the multiple column light-emitting diode circuits is disposed adjacent to the first column light-emitting diode circuit, and a third column light-emitting diode circuit among the multiple column light-emitting diode circuits is disposed adjacent to the second column light-emitting diode circuit; Wherein the copper-clad structure further includes: A second copper-clad layer that is electrically coupled to the third column light-emitting diode circuit and, in a projection on the first surface of the printed circuit board, at least covers the third column light-emitting diode circuit.

9. The backlight device according to claim 8, wherein The multiple copper wires further include at least a first copper wire, at least a second copper wire, and at least a third copper wire. The at least a first copper wire is electrically coupled to a first side end point of the second copper-clad layer, the at least a second copper wire is electrically coupled to a second side end point of the second copper-clad layer, the at least a third copper wire is electrically coupled to a middle end point of the second copper-clad layer, and the first side end point, the second side end point, and the middle end point are located on a long side of the second copper-clad layer, and a distance between the first side end point and the middle end point is equal to a distance between the second side end point and the middle end point.

10. The backlight device according to claim 8, wherein the printed circuit board has multiple holes, the first copper-clad layer electrically couples the first column light-emitting diode circuit and the second column light-emitting diode circuit through the multiple holes, and in a projection on the first surface of the printed circuit board, the first copper-clad layer further covers the multiple holes.

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