CN114695331A

CN114695331A - Backlight device

Info

Publication number: CN114695331A
Application number: CN202210335011.XA
Authority: CN
Inventors: 林斯岩; 黄馨谆
Original assignee: AU Optronics Corp
Current assignee: AU Optronics Corp
Priority date: 2021-11-19
Filing date: 2022-03-31
Publication date: 2022-07-01
Also published as: TWI777858B; TW202321616A

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 arranged on the first surface of the printed circuit board, and each light emitting diode circuit comprises a first row of light emitting diode circuits and a second row of light emitting diode circuits. The conductive structure is disposed on the second surface of the printed circuit board and electrically coupled to the led circuits, and includes a first conductor and a plurality of wires, wherein the first conductor is electrically coupled to the first row of led circuits, and a projection on the first surface of the printed circuit board at least covers the first row of led circuits. The wires are electrically coupled to the first conductors, wherein the impedances of the wires are substantially matched to each other.

Description

Backlight device

Technical Field

The present disclosure relates to backlight devices, and particularly to a backlight device having a conductive structure.

Background

Backlight devices are widely used in various electronic products, and the backlight devices generally include light emitting diode circuits. In the conventional led circuit, the layout and routing manner (e.g., X-Y line manner) of the led circuit may be affected by impedance mismatch, which may cause different light emitting degrees when the led circuits at different positions receive different power signals, thereby causing the problem of uneven brightness of the backlight device. Therefore, how to develop a related art capable of overcoming the above problems is an important issue in the art.

Disclosure of Invention

The present invention is directed to a backlight device to solve at least one of the problems set forth above.

One embodiment of the 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 row of light emitting diode circuits and a second row of light emitting diode circuits, and the first row of light emitting diode circuits and the second row 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, and is electrically coupled to the plurality of led circuits for transmitting a power supply to the plurality of led circuits, wherein the conductive structure comprises a first conductor and a conductive wire, wherein the first conductor is electrically coupled to the first row of led circuits, and a projection on the first surface of the printed circuit board at least covers the first row of led circuits. The plurality of wires are electrically coupled to the first conductor, wherein the impedances of the wires are substantially matched with each other.

Another embodiment of the present invention is a backlight device comprising a printed circuit board, a plurality of 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. The multiple rows of light emitting diode circuits are arranged on the first surface of the printed circuit board. The copper spreading structure is arranged on the second surface of the printed circuit board and at least electrically coupled to a first row of light emitting diode circuits in the multiple rows of light emitting diode circuits, wherein the copper spreading structure comprises a first copper spreading layer and multiple copper wires, the first copper spreading layer is electrically coupled to the first row of light emitting diode circuits, and a projection on the first surface of the printed circuit board at least covers the first row of light emitting diode circuits. A plurality of copper wires are electrically coupled between the first copper spreading layer and the input terminal, wherein the lengths of the copper wires between the first copper spreading layer and the input terminal are substantially equal to each other.

The invention has the advantages that the conducting wire in the conducting structure is matched in impedance through the configuration of the conducting structure, so that the brightness difference between different light-emitting positions of the backlight device is reduced, and the problem of uneven brightness of the backlight device is solved.

Drawings

FIG. 1 is a schematic diagram of a backlight apparatus shown in accordance with some embodiments.

FIG. 2 is a schematic diagram of a portion of the backlight apparatus of FIG. 1 shown in accordance with some embodiments.

FIG. 3 is a schematic diagram of a portion of the backlight apparatus of FIG. 1 shown in accordance with some embodiments.

FIG. 4 is a schematic diagram of a portion of the backlight apparatus of FIG. 1 shown in accordance with some embodiments.

FIG. 5 is a schematic diagram of a portion of the backlight apparatus of FIG. 1 shown in accordance with some embodiments.

FIG. 6 is a schematic diagram of a backlight apparatus shown in accordance with some embodiments.

The reference numbers are as follows:

100: backlight device

101: printed circuit board

103: first surface

105: second surface

110: conductive structure

120: light emitting diode circuit

122: first column light emitting diode circuit

124: second row LED circuit

126: third column LED circuit

150,151,152,153: unit cell

211: conductor

213: wire 230: hole(s)

311: long side 314,315,316: conducting wire

320: input terminal

324,325,326: endpoint

410: conductive structure

411,412: conductor

413: conducting wire

430: hole(s)

450,451,452: unit cell

511,512: long side

514,515,516,517,518,519: conducting wire

520: input terminal

524,525,526,527,528,529: endpoint

VLED, VLED1, VLED2, VLED3, VLED 4: supply power

Detailed Description

When an element is referred to as being "connected" or "coupled," it can be referred to as being "electrically connected" or "electrically coupled. "connected" or "coupled" may also be used to indicate that two or more elements are in mutual engagement or interaction. Moreover, although terms such as "first," "second," …, etc., may be used herein to describe various elements, these terms are used merely to distinguish one element or operation from another element or operation described in similar technical terms. Unless the context clearly dictates otherwise, the terms do not specifically refer or imply an order or sequence nor are they intended to limit the invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms, including "at least one", unless the content clearly indicates otherwise. "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 will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions integers, steps, operations, elements, components, and/or groups thereof.

FIG. 1 is a schematic diagram of a backlight apparatus 100 shown according to some embodiments. As shown in fig. 1, the backlight device 100 includes a printed circuit board 101, a conductive structure 110 and a plurality of led circuits 120, wherein the printed circuit board 101 has a first surface 103 and a second surface 105 opposite to each other, the led circuits 120 are disposed on the first surface 103 of the printed circuit board 101, the conductive structure 110 is disposed on the second surface 105 of the printed circuit board 101, and the conductive structure 110 is electrically coupled to the led circuits 120 for transmitting a supply power VLED to the led circuits 120. It should be noted that fig. 1 only shows a single led circuit 120 for convenience and clarity of illustration, but the number of led circuits is not limited to that shown in fig. 1. In other words, the number of the conductive structures 110 and the led circuits 120 shown in fig. 1 may be more or less, and is not limited to that shown in fig. 1.

As shown in fig. 1, in some embodiments, the combination of the led circuit 120 and the conductive structure 110 may be used as a unit 150, and one or more units 150 may be disposed on the printed circuit board 101, that is, more or less similar units 150 may be disposed on the printed circuit board 101, and each of the one or more units 150 is electrically coupled to different power supplies, for example, as shown in fig. 1, three units 151-153 are respectively electrically coupled to different power supplies, the unit 151 is electrically coupled to the VLED1, the unit 152 is electrically coupled to the VLED2, and the unit 153 is electrically coupled to the VLED 3. FIG. 1 is merely an example, and is not intended to limit the present invention.

As shown in FIG. 1, in some embodiments, the LED circuits 120 are arranged in rows and columns, and the LED circuits 120 include a first column 122 and a second column 124 configured adjacent to each other. In some embodiments, there may be more or fewer similar rows and columns of LED circuits 120 on the first surface 103 of the printed circuit board 101, which are not shown for clarity of illustration.

FIG. 2 is a schematic diagram illustrating a portion of the backlight apparatus 100 of FIG. 1, according to some embodiments. As shown in fig. 2, the conductive structure 110 includes a first conductor 211 and a plurality of conductive lines 213. The first conductor 211 is electrically coupled to the first row of led circuits 122, and a projection onto the first surface 103 of the printed circuit board 101 at least covers the first row of led circuits 122. The conductive lines 213 are electrically coupled to the first conductor 211, wherein the impedances of the conductive lines 213 are substantially matched to each other.

In some embodiments, the first conductor 211 and the conductive line 213 of the conductive structure 110 are used for transmitting the supply power VLED to the led circuit 120, and may be made of copper, aluminum, silver, or other suitable conductive materials. In some embodiments, the first conductor 211 and the conductive line 213 are implemented by copper, but the invention is not limited thereto.

In some embodiments, the printed circuit board 101 has a plurality of holes 230, wherein the first conductor 211 is electrically coupled to the first row of led circuits 122 and the second row of led circuits 124 through the holes 230. In some embodiments, as shown in fig. 2, the projection of the first conductor 211 on the first surface 103 of the printed circuit board 101 also covers the hole 230 electrically coupling the first conductor 211 and the second row of led circuits 124.

FIG. 3 is a schematic diagram of a portion of the backlight apparatus 100 of FIG. 1, according to some embodiments. The conductive lines in the conductive structure 110 include conductive lines 314,315, and 316, wherein the conductive lines 314,315, and 316 correspond to the conductive lines 213 of fig. 2 and are electrically coupled to the input terminal 320, and are used for receiving the supply power VLED from the input terminal 320. In some embodiments, the conductive lines 314-316 are electrically coupled to different ends of the first conductor 211, wherein the conductive line 314 is electrically coupled to a side end 324 of the first conductor 211, the conductive line 315 is electrically coupled to a middle end 325 of the first conductor 211, and the conductive line 316 is electrically coupled to a side end 326 of the first conductor 211. In a further embodiment, the conductive lines 314-316 are each electrically coupled to different ends of the long side 311 of the first conductor 211, such as: the long sides have

side terminals

324 and 326 and middle terminals 325, which are electrically connected to the conductive wires 314-316, respectively. It should be noted that, for the sake of convenience and clarity, fig. 3 only shows three wires 314 to 316, but the number of the wires is not limited to that shown in fig. 3. In other words, the number of the wires 213 in the conductive structure 110 shown in fig. 3 may be three or more, and is not limited to that shown in fig. 3.

As shown in fig. 3, 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, i.e., the distance between different ends of the first conductor 211 electrically coupled to the

wires

314 and 315 is substantially equal to the distance between different ends of the first conductor 211 electrically coupled to the

wires

316 and 315, and the impedances of the wires 314-316 are matched by the arrangement of the wires having substantially equal lengths.

Referring to fig. 1 to 3, in some embodiments, one or more units 150 composed of the led circuits 120 and the conductive structures 110 are disposed on the printed circuit board 101 of the backlight device 100, so that the impedances of the wires 314 to 316 are matched with 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, the conventional layout and routing method (e.g., X-Y routing method) of the led circuit and the power supply circuit may cause the brightness difference between different light-emitting positions of the backlight device to be 40%, and compared with the conventional layout and routing method (e.g., X-Y routing method), the embodiment of the invention may be used to reduce the brightness difference of the entire backlight device to be less than 5%.

FIG. 4 is a schematic diagram of a portion of the backlight apparatus 100 of FIG. 1, according to some embodiments. As shown in fig. 4, the plurality of led circuits 120 further includes a third led circuit 126 disposed adjacent to the second led circuit 124. The conductive structure 410 is similar in arrangement and function to the conductive structure 110 (see fig. 2) discussed above, and is used for transmitting the supply power VLED to the led circuit 120. In some embodiments, the conductive structure 410 includes a first conductor 411, a second conductor 412, and a plurality of conductive lines 413 respectively corresponding to the first conductor 211 and the plurality of conductive lines 213 of the conductive structure 110 (refer to fig. 2), wherein the conductor 411 is electrically coupled to the first row of led circuits 122 and the second row of led circuits 124, and the conductor 412 is electrically coupled to the third row of led 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 row of led 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 row of led circuits 126. The conductive line 413 is electrically coupled to the

conductors

411 and 412, wherein the impedances of the conductive line 413 are substantially matched to each other.

In some embodiments, the

conductors

411 and 412 and the conductive line 413 in the conductive structure 410 are used for transmitting the power VLED to the led circuit 120, and may be made of suitable conductive materials such as copper, aluminum, silver, etc., in some embodiments, the

conductors

411 and 412 and the conductive line 413 are implemented by copper, but the invention is not limited thereto.

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 shown in fig. 4, 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.

FIG. 5 is a schematic diagram of a portion of the backlight apparatus 100 of FIG. 1, according to some embodiments. As shown in FIG. 5, the conductive lines of the conductive structure 410 include conductive lines 514-519, wherein the conductive lines 514-519 correspond to the conductive lines 413 of FIG. 4 and are electrically coupled to the input terminal 520, and are used for receiving a supply power VLED from the input terminal 520. In some embodiments, the conductive lines 514-516 are electrically coupled to different ends of the first conductor 411, wherein the conductive line 514 is electrically coupled to a side end 524 of the first conductor 411, the conductive line 515 is electrically coupled to a middle end 525 of the first conductor 411, and the conductive line 516 is electrically coupled to a side end 526 of the first conductor 411. The conductive wires 517-519 are electrically coupled to different ends of the second conductor 412, wherein the conductive wire 517 is electrically coupled to a side end 527 of the second conductor 412, the conductive wire 518 is electrically coupled to a middle end 528 of the second conductor 412, and the conductive wire 519 is electrically coupled to a side end 529 of the second conductor 412. In a further embodiment, the conductive wires 514-516 are electrically coupled to different ends of the long side 511 of the first conductor 411, such as: the long sides have

side terminals

524 and 526 and middle terminals 525 electrically connected to the conductive wires 514-516, respectively. The conductive wires 517-519 are electrically coupled to different ends of the long side 512 of the second conductor 412, for example: the long sides have

side terminals

527 and 529 and a middle terminal 528, which are electrically connected to the conductive wires 517-519 respectively. It should be noted that, for the sake of convenience and clarity, fig. 5 only shows six wires 514-519, but the number of the wires is not limited to that shown in fig. 5. In other words, the number of the conductive lines 413 in the conductive structure 410 shown in fig. 5 may be six or more, and is not limited to that shown in fig. 5.

As shown in fig. 5, 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, i.e., the distance between the conductive line 514 and the conductive line 515 electrically coupled to different ends of the first conductor 411 is substantially equal to the distance between the conductive line 516 and the conductive line 515 electrically coupled to different ends 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, i.e., the distance between the conductive line 517 and the conductive line 518 electrically coupled to different ends of the second conductor 412 is substantially equal to the distance between the conductive line 519 and the conductive line 518 electrically coupled to different ends of the second conductor 412, and the impedances of the conductive lines 514-519 are matched with each other by the arrangement of the conductive lines being substantially equal in length.

Referring to fig. 1 and 4-5, in some embodiments, the combination of the led circuit 120 and the conductive structure 410 may be used as a unit 450, and one or more units 450 may be disposed on the printed circuit board 101, for example, three units 450 formed by the combination of the led circuit 120 and the conductive structure 410 are disposed on the printed circuit board 101, as shown in fig. 1 and 4. In some embodiments, the configuration of the one or more units 450 enables the impedances of the wires 514 to 519 to be matched with each other, thereby reducing the overall brightness difference of the backlight device 100 and improving the problem of non-uniform brightness of the backlight device. In some embodiments, the embodiment of the invention can be used to reduce the overall brightness difference of the backlight device 100 to less than 2% compared to the conventional layout and routing manner (e.g., X-Y line manner) of the led circuit and the power supply circuit.

FIG. 6 is a schematic diagram of a backlight apparatus 100 shown according to some embodiments. As shown in fig. 6, the combination of the led circuit 120 and the conductive structure 110 may be used as the unit 150, and the combination of the led circuit 120 and the conductive structure 410 may be used as the unit 450, two

units

151 and 152 and two units 451 and 452 may be simultaneously disposed on the printed circuit board 101, in other words, two

units

151 and 152 combined by the led circuit 120 and the conductive structure 110 and two units 451 and 452 combined by the led circuit 120 and the conductive structure 410 are simultaneously disposed on the printed circuit board 101, and the 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 may be disposed on the printed circuit board 101, and the illustration in fig. 6 is merely an example and is not intended to limit the present invention.

In summary, the conductive structure configuration of the present invention matches the impedance of the conductive wires in the conductive structure, 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.

Although the present invention has been described with reference to the above embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention.

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 LED circuits disposed on the first surface of the printed circuit board, wherein the plurality of LED circuits includes a first row of LED circuits and a second row of LED circuits, and the first row of LED circuits and the second row of LED 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 led circuits, and configured to transmit a power supply to the plurality of led circuits, wherein the conductive structure comprises:

a first conductor electrically coupled to the first row of LED circuits, wherein a projection on the first surface of the printed circuit board at least covers the first row of LED circuits; and

a plurality of wires electrically coupled to the first conductor, wherein the wires are matched in impedance.

2. The backlight device as claimed in claim 1, wherein

The plurality of wires include 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 configured to receive the power supply from the input terminal, the at least one first wire is electrically coupled to a first side end of the first conductor, the at least one second wire is electrically coupled to a second side end of the first conductor, the at least one third wire is electrically coupled to a middle end of the first conductor, and the first side end, the second side end, and the middle end are located on a long side of the first conductor.

3. The backlight as claimed in claim 2, wherein

A plurality of the light emitting diode circuits further comprise:

a third row of LED circuits disposed adjacent to the second row of LED circuits;

wherein the conductive structure further comprises:

a second conductor electrically coupled to the third row of LED circuits, wherein the projection on the first surface of the printed circuit board at least covers the third row of LED circuits.

4. A backlight as claimed in claim 3, in which

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 used for receiving the power supply from the input terminal, the at least one first wire is electrically coupled to a first side end of the second conductor, the at least one second wire is electrically coupled to a second side end of the second conductor, the at least one third wire is electrically coupled to a middle end of the second conductor, and the first side end, the second side end and the middle end are located on a long side of the second conductor.

5. The backlight apparatus of claim 1, wherein the printed circuit board has a plurality of holes, the first conductor is electrically coupled to the first row of led circuits and the second row of led circuits through the plurality of holes, and a projection of the first conductor onto the first surface of the printed circuit board further covers the plurality of holes.

6. A backlight device, comprising:

a plurality of row light emitting diode circuits configured on the first surface of the printed circuit board;

a copper spreading structure disposed on the second surface of the printed circuit board and electrically coupled to at least a first row of the plurality of rows of led circuits, wherein the copper spreading structure comprises:

a first copper-spreading layer electrically coupled to the first row of LED circuits, wherein a projection on the first surface of the printed circuit board at least covers the first row of LED circuits; and

and a plurality of copper wires electrically coupled between the first copper-clad layer and an input terminal, wherein the lengths of the plurality of copper wires between the first copper-clad layer and the input terminal are equal to each other.

7. The backlight device as claimed in claim 6, wherein

The plurality of copper wires comprise at least one first copper wire, at least one second copper wire and at least one third copper wire, wherein the at least one first copper wire is electrically coupled with a first side end point of the first copper-clad layer, the at least one second copper wire is electrically coupled with a second side end point of the first copper-clad layer, the at least one third copper wire is electrically coupled with a middle end point of the first copper-clad layer, the first side end point, the second side end point and the middle end point are positioned on a long side of the first copper-clad layer, and the distance between the first side end point and the middle end point is equal to the distance between the second side end point and the middle end point.

8. The backlight device as claimed in claim 6, wherein

A second row of the plurality of rows of LED circuits is disposed adjacent to the first row of LED circuits, and a third row of the plurality of rows of LED circuits is disposed adjacent to the second row of LED circuits;

wherein the copper-laying structure further comprises:

a second copper layer electrically coupled to the third row of LED circuits, wherein the projection on the first surface of the printed circuit board at least covers the third row of LED circuits.

9. The backlight device as claimed in claim 8, wherein

The plurality of copper wires further includes at least one first copper wire, at least one second copper wire and at least one third copper wire, wherein the at least one first copper wire is electrically coupled to a first side end of the second copper-clad layer, the at least one second copper wire is electrically coupled to a second side end of the second copper-clad layer, the at least one third copper wire is electrically coupled to a middle end of the second copper-clad layer, the first side end, the second side end and the middle end are located on a long side of the second copper-clad layer, and a distance between the first side end and the middle end is equal to a distance between the second side end and the middle end.

10. The backlight apparatus of claim 8 wherein the printed circuit board has a plurality of holes, the first copper spreading layer is electrically coupled to the first row of led circuits and the second row of led circuits through the plurality of holes, and a projection of the first copper spreading layer onto the first surface of the printed circuit board further covers the plurality of holes.