Backlight unit and display device including the same

Patent metadata

Field	Value
Publication number	US-12510784-B2
Application number	US-202418987984-A
Country	US
Kind code	B2
Filing date	Dec 19, 2024
Priority date	Dec 28, 2023
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

Disclosed is a backlight unit in which a PCB and a lens are prevented from lifting off from an edge of a reflective plate and are fixed to the reflective plate when manufacturing an LED array. Further, the display device including the same is provided. To this end, the backlight unit is configured such that the lenes disposed on the PCB and arranged so as to be spaced from each other are fixedly inserted into openings defined in the reflective plate, wherein the openings defined in different areas of the reflective plate have different shapes and widths.

First claim

What is claimed is:

1 . A backlight unit comprising:
a printed circuit board; at least one lens on the printed circuit board; and a reflective plate having at least one opening that corresponds to the at least one lens, wherein the reflective plate is on the printed circuit board such that the at least one lens is inserted into the at least one opening, wherein the at least one opening includes:
a first opening at a first side edge of both opposing side edges in a first direction of the reflective plate;
a second opening located at a second side edge of the both opposing side edges in the first direction of the reflective plate; and
at least one third opening located between the first opening and the second opening,
wherein the reflective plate includes two protrusions that protrude and face each other within the at least one third opening.

2 . The backlight unit of claim 1 , wherein in a plan view of the backlight unit, each of the first opening, the second opening, and the at least one third opening has a first side edge portion, a second side edge portion, and a middle portion between the first side edge portion and the second side edge portion,
wherein a width in a second direction of the first side edge portion of the first opening is smaller than a width in a second direction of each of the second side edge portion and the middle portion of the first opening, wherein the second direction intersects with the first direction, wherein a width in the second direction of the second side edge portion of the second opening is smaller than a width in the second direction of each of the first side edge portion and the middle portion of the second opening, wherein a width in the second direction of the middle portion of the at least one third opening is smaller than a width in the second direction of each of the first side edge portion and the second side edge portion of the at least one third opening.

3 . The backlight unit of claim 2 , wherein the first side edge of the reflective plate is a left side edge of the reflective plate, and the second side edge of the reflective plate is a right side edge of the reflective plate.

4 . The backlight unit of claim 1 , wherein in a plan view of the backlight unit, the first opening, the second opening, and the at least one third opening have different shapes from each other.

5 . The backlight unit of claim 1 , wherein in a plan view of the backlight unit, the first opening and the second opening have shapes that are symmetrical to each other with respect to an imaginary vertical line through a center in the first direction of the reflective plate.

6 . The backlight unit of claim 1 , wherein each of the at least one lens is on the printed circuit board and are arranged so as to be spaced from each other by an equal spacing along the first direction.

7 . The backlight unit of claim 1 , wherein a width in a second direction of each of the at least one lens is larger than a width in the second direction of the printed circuit board, wherein the second direction intersects the first direction.

8 . The backlight unit of claim 1 , wherein each of the at least one lens receives therein each a light-emitting diode.

9 . The backlight unit of claim 1 , further comprising:
a reinforcement frame accommodating therein the reflective plate into which the at least one lens on the printed circuit board is inserted.

10 . The backlight unit of claim 1 , wherein a diffuser sheet is on the reflective plate,
wherein at least one optical sheet is on the diffuser sheet.

11 . A display device comprising:
the backlight unit according to claim 1 ; and a display panel disposed on the backlight unit.

12 . The display device of claim 11 , wherein the backlight unit further includes a reinforcement frame accommodating therein the reflective plate into which the at least one lens on the printed circuit board is inserted,
wherein the reinforcement frame includes four side walls coupled to each other to define an accommodation space of a rectangular shape in a plan view of the display device, wherein the four side walls extend upwardly and respectively from four side edges of a bottom surface of the reinforcement frame.

13 . The display device of claim 12 , wherein a height from the bottom surface of each of a first sidewall and a second sidewall facing each other is larger in each of both opposing side edges thereof than in a center thereof,
wherein a lower surface of each of the first sidewall and the second sidewall is curved to have a first curvature having a value greater than 0, wherein an upper surface of each of the first sidewall and the second sidewall is curved to have a second curvature greater than the first curvature.

14 . The display device of claim 11 , wherein the reflective plate includes:
a first protrusion protruding into the at least one third opening from one of both opposing sides in the second direction of the third opening in a middle area in the first direction of the third opening; and a second protrusion protruding into the third opening from the other of the both opposing sides in the second direction of the third opening in the middle area in the first direction of the third opening.

15 . The display device of claim 11 , further comprising:
at least one curved reinforcing bar of a step structure supporting the backlight unit.

16 . The display device of claim 15 , wherein the at least one curved reinforcing bar includes:
a first vertical portion; a first horizontal portion vertically bent from one end of the first vertical portion; a second vertical portion vertically bent from one end of the first horizontal portion; and a second horizontal portion vertically bent from one end of the second vertical portion.

17 . The display device of claim 16 , wherein a back surface of the second horizontal portion and an outer surface of the second vertical portion form the step structure, and a printed circuit board connected to the display panel is fixed to the step structure.

Assignees

• Lg Display Co Ltd

Inventors

• Seo Jeongho
• Park Kiduck

Classifications

• G02F1/133603

  with LEDs · CPC title

• G02F1/133605 Primary

  including specially adapted reflectors · CPC title

• G02F1/133606

  including a specially adapted diffusing, scattering or light controlling members · CPC title

• G02F1/133608 Primary

  including particular frames or supporting means · CPC title

• G02F1/133607 Primary

  the light controlling member including light directing or refracting elements, e.g. prisms or lenses · CPC title