Lateral backlight module LED lamp arrangement method and backlight module thereof

Abstract

The invention discloses an LED lamp arrangement method of a side-entry backlight module and the backlight module thereof, and the method comprises the following steps: (1) measuring to obtain the width L of a visible area of the backlight module, and determining the number N of LED lamps needing to be arranged; (2) calculating the lamp spacing P according to a formula P = L / (N + 0.25), and calculating according to P = L / 2 when N is equal to 1; and (3) arranging the LED lamps, centering the whole group of LED lamps in an area below the visible area, and finishing arrangement according to the arrangement rule of even-number lamps or odd-number lamps. By means of the method, the design efficiency can be greatly improved, the light-emitting angle dark area of the LED lamp is uniform, lattice points of the light guide plate can be conveniently and easily arranged and debugged, and therefore the visual effect that the brightness and the darkness of a product are not uniform is improved.

Description

Technical Field

[0001] This invention belongs to the field of backlight module technology, specifically relating to an LED lamp arrangement method for a side-lit backlight module and the backlight module thereof. Background Technology

[0002] With the widespread use of LCD screens, backlight modules are applied in a wide range of industries, including industrial equipment, banking terminals, office automation, communications, electronic toys, and consumer products such as home appliances, telephones, mobile phones, laptops, MP3 players, MP4 players, PDAs, instruments, electronic dictionaries, electronic notebooks, and learning machines. These LCD screens are provided with a light source by the backlight module. The backlight module works by converting the incident line or point light source into a uniformly emitted surface light source. Depending on the placement of the light source, backlight modules can be divided into edge-lit backlight modules and direct-lit backlight modules. Edge-lit structures are generally suitable for small to medium-sized backlight modules and are mainly used in mobile phones, laptops, automotive panels, and monitors, featuring lightweight and thin designs.

[0003] For edge-lit backlight modules, the number of LEDs used in the backlight varies depending on performance requirements; some have more, some fewer. Therefore, the spacing between the LEDs differs accordingly. The light guide plate is adjusted based on the LED spacing to improve the optical effect of the bright and dark areas between the backlight LEDs and the overall visible area. Currently, LED spacing calculations are often arbitrarily designed based on the designer's experience (e.g., ...). Figure 1 As shown, the three backlight modules (a, b, and c) lack a guiding method, resulting in inconsistent LED spacing. This leads to variations in the size of the dark areas in the LED emission angle, making it difficult to arrange and adjust the dot pattern on the light guide plate. Ultimately, this results in uneven brightness and darkness in the LCD screen's visual effect. Therefore, there is an urgent need to provide a method for calculating the LED spacing of backlight modules to more efficiently and uniformly place LEDs and improve the quality of the LCD screen. Summary of the Invention

[0004] The purpose of this invention is to provide a method for arranging LEDs in a side-lit backlight module and a backlight module thereof, so as to improve design efficiency and product quality.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] On the one hand, a method for arranging LEDs in a side-lit backlight module is provided, including the following steps:

[0007] (1) Measure and obtain the width L of the visible area of ​​the backlight module, and determine the number N of LEDs to be arranged;

[0008] (2) The lamp spacing P is calculated using the formula P=L / (N+0.25). When N=1, it is calculated using P=L / 2.

[0009] (3) Arrange the LED lights,

[0010] (3.1) When N is odd,

[0011] a. Draw a center line M along the vertical direction of the visible area width L;

[0012] b. Place an LED light at the position of center line M on the edge of the light guide plate as a reference light;

[0013] c. With the reference light as the center, arrange (N-1) / 2 LEDs symmetrically on the left and right sides of the light guide plate edge and center line M, according to the LED spacing P.

[0014] (3.2) When N is even,

[0015] a. Draw a center line M along the vertical direction of the visible area width L;

[0016] b. Arrange the first and second LED lights at positions P / 2 distances from the center line M on the left and right sides of the light guide plate edge;

[0017] c. At the edge of the light guide plate, using the first and second LEDs as a reference, arrange (N-2) / 2 LEDs symmetrically on both sides of the center line M, according to the lamp spacing P.

[0018] Preferably, the backlight module is a square, window-like backlight module.

[0019] On the other hand, a side-lit backlight module is also provided, including a substrate, LEDs fixed on the substrate, a light guide plate, light guide dots, and an optical film. The substrate is located on the light-incident surface of the light guide plate, the light guide dots are disposed on the light-guiding surface of the light guide plate, and the optical film is disposed on the light-emitting surface of the light guide plate. The LEDs are arranged on the substrate according to the method of claim 1 or 2.

[0020] The principle of this invention is to precisely control the lamp spacing through a standardized formula, thereby achieving a uniform distribution of the dark area of ​​the LED lamp's luminous angle, and thus optimizing the dot arrangement of the light guide plate and improving the optical effect of the backlight module.

[0021] Preferably, the density of the light guide dots increases in a gradient from the direction away from the light source side, and at the same horizontal position, the density of the light guide dots in the area directly opposite the LED lamp is lower than the density of the light guide dots in the area directly opposite the middle of two adjacent lamps.

[0022] Preferably, the light guide plate is a wedge-shaped light guide plate, with the thickness of its light-incident side being greater than the thickness of its light-outcident side; and the light-incident surface of the light guide plate is provided with a microprism array or a V-cut microstructure.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1. The method of the present invention can greatly improve design efficiency, make the dark area of ​​the LED light emission angle uniform, facilitate the easy arrangement and adjustment of the dot pattern of the light guide plate, and thus improve the visual effect of uneven brightness of the product.

[0025] 2. Regardless of whether the number of LEDs is odd or even, they are arranged symmetrically with the center line of the visible area as the reference to ensure that the optical paths on the left and right sides are completely consistent and to avoid one side being too bright or too dark.

[0026] 3. By introducing a lamp spacing calculation formula with a correction factor of 0.25, the distance between the edge lamp beads and the edge of the light guide plate is made smaller than that of the traditional equal-spacing arrangement scheme, which enhances the brightness of the edge of the visible area and forms a smooth transition with the central area, significantly reducing the bright and dark stripes on the light-incident side.

[0027] 4. By setting the light guide dot density to a non-uniform distribution of "low density in the area directly opposite the lamp beads and high density in the area between the two lamps", the non-uniformity of light intensity distribution can be specifically compensated, further improving the uniformity of light output. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of a traditional LED light;

[0029] Figure 2 A schematic diagram of an LED lamp structure arranged using the method of the present invention;

[0030] Figure 3 This is a schematic diagram of the odd-numbered LED lamp arrangement structure in this invention;

[0031] Figure 4 This is a schematic diagram of the even-numbered LED lamp arrangement structure in this invention;

[0032] Figure 5 This invention relates to a side-lit backlight module.

[0033] Figure label:

[0034] 1. Visible area, 2. LED light, 3. Dark area of ​​the light emission angle, 4. Center line, 5. Light guide plate, 6. Substrate, 7. Light guide dots, 8. Diffuse film, 9. Brightness enhancement film, 10. Reflective film. Detailed Implementation

[0035] To make the objectives and advantages of the present invention clearer, the present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0036] Example 1

[0037] This invention relates to a method for arranging LEDs in a side-lit backlight module, comprising the following steps:

[0038] (1) Measure and obtain the width L of the visible area 1 of the backlight module, and determine the number N of LED lights 2 that need to be arranged;

[0039] (2) The lamp spacing P is calculated using the formula P=L / (N+0.25). When N=1, it is calculated using P=L / 2.

[0040] (3) Arrange the LED lights 2, centering the entire group of LED lights 2 in the area below the width of the visible area 1, such as... Figure 2 As shown, the arrangement is completed according to the even-number or odd-number lamp arrangement rules; the best embodiment of the present invention is the above formula calculation plus the centered symmetrical arrangement method.

[0041] Specifically, (3.1) when N is odd,

[0042] a. Draw a center line 4 along the vertical direction of the visible area 1 width L;

[0043] b. Place an LED light 2 at the edge of the light guide plate 5 and the center line 4 as a reference light;

[0044] c. With the reference light as the center, arrange (N-1) / 2 LED lights 2 symmetrically on the edge of the light guide plate 5 and on both sides of the center line 4, according to the spacing P of the LED lights 2.

[0045] like Figure 3 As shown, taking a 32-inch LCD screen as an example, the width of the visible area 1 of the backlight module is L=708mm. The design uses N=5 LEDs 2.

[0046] According to the formula P=L / (N+0.25)=708 / 5.25≈134.86mm.

[0047] First, the center line 4 of the visible area 1 is drawn, and the first reference lamp is placed at the edge of the light-incident side of the light guide plate 5, at the position of the center line 4. Then, two LEDs 2 are placed on each side of the reference lamp at a spacing of 78.66mm, ultimately forming a symmetrical arrangement of five LEDs. The uniform distribution of the dark area 3 of the LED 2 in the above-mentioned LCD screen optimizes the dot arrangement of the light guide plate 5 and improves the optical effect of the backlight module.

[0048] (3.2) When N is even,

[0049] a. Draw a center line 4 along the vertical direction of the visible area 1 width L;

[0050] b. Arrange the first and second LED lights 2 at the edges of the light guide plate 5 and at the left and right sides of the center line 4, respectively, at a distance of P / 2 from the center line 4;

[0051] c. At the edge of the light guide plate 5, taking the first and second LED lights 2 as a reference, arrange (N-2) / 2 LED lights 2 symmetrically on both sides of the center line 4 according to the light spacing P.

[0052] like Figure 4 As shown, taking a 15.6-inch laptop screen as an example, the width of the viewable area 1 is L=344mm, and N=4 LEDs are selected 2.

[0053] Calculate P = L / (4+0.25) = 344 / 4.25 = 80.94 mm.

[0054] The first and second LED lights 2 are placed at a distance of 40.47 mm (P / 2) on each side of the center line 4. Then, using these two lights as a reference, the remaining two lights are symmetrically arranged outwards at a spacing of 80.94 mm.

[0055] Example 2

[0056] like Figure 5 As shown, the present invention also provides a side-lit backlight module, including a substrate 6, LEDs 2 fixed on the substrate 6, a light guide plate 5, light guide dots 7, and an optical film. The optical film includes a diffusion film 8 and a brightness enhancement film 9 sequentially disposed on one side of the light-emitting surface of the light guide plate 5, and a reflective film 10 is also disposed on one side of the light-guiding surface of the light guide plate 5. The substrate 6 is located on the light-incident surface of the light guide plate 5, the light guide dots 7 are disposed on the light-guiding surface of the light guide plate 5, the optical film is disposed on the light-emitting surface of the light guide plate 5, and the LEDs 2 are arranged on the substrate 6 according to the method described above.

[0057] The density of the light guide dots 7 increases gradually with the direction away from the light-incident side. At the same horizontal position, the density of the light guide dots 7 in the area directly opposite the LED 2 is lower than the density in the area directly opposite the middle of two adjacent LEDs. The light guide plate 5 is wedge-shaped overall, with its thickness on the light-incident side greater than that on the light-outcident side. Specifically, the thickness on the light-incident side is 1.2 mm, and the thickness on the light-outcident side (far end) is 0.6 mm. The wedge-shaped structure helps to break the total internal reflection condition, allowing more light to escape from the light-outcident surface. The light-incident surface of the light guide plate 5 is provided with a microprism array or a V-cut microstructure; specifically, the light-incident surface is processed with a V-cut microstructure, with the apex angle of the V-shaped groove being 90°~120°, the groove depth 0.05 mm~0.1 mm, and the groove spacing 0.1 mm~0.3 mm. This microstructure can bend large-angle light emitted from the LED towards the normal direction, improving the efficiency of light coupling into the light guide plate 5. Actual measurements show an increase in light coupling efficiency of over 15%.

[0058] The above embodiments are merely specific examples to further illustrate the purpose, technical solution, and beneficial effects of the present invention, and the present invention is not limited thereto. Any modifications, equivalent substitutions, improvements, etc., made within the scope of the disclosure of the present invention are included within the protection scope of the present invention.

Claims

1. A method for arranging LEDs in a side-lit backlight module, characterized in that: Includes the following steps: (1) Measure and obtain the width L of the visible area of ​​the backlight module, and determine the number N of LED lights (2) to be arranged; (2) The lamp spacing P is calculated using the formula P=L / (N+0.25). When N=1, it is calculated using P=L / 2. (3) Arrange LED lights (2), (3.1) When N is odd, a. Draw a center line (4) along the longitudinal direction of the width L of the visible area (1); b. Place an LED light (2) at the edge of the light guide plate (5) and the center line (4) as a reference light; c. With the reference lamp as the center, arrange (N-1) / 2 LED lamps (2) symmetrically on the edge of the light guide plate (5) and on both sides of the center line (4) according to the spacing P of the LED lamps (2); (3.2) When N is even, a. Draw a center line (4) along the longitudinal direction of the width L of the visible area (1); b. Arrange the first and second LED lights (2) at the edges of the light guide plate (5) and at the left and right sides of the center line (4) at a distance of P / 2 from the center line (4); c. At the edge of the light guide plate (5), with the first and second LED lights (2) as the reference, arrange (N-2) / 2 LED lights (2) symmetrically on the left and right sides of the center line (4) according to the light spacing P.

2. The LED lamp arrangement method for a side-lit backlight module according to claim 1, characterized in that: The backlight module is a square, window-like backlight module.

3. A side-lit backlight module, comprising a substrate (6), an LED lamp fixed on the substrate (6), a light guide plate (5), light guide dots (7), and an optical film, wherein the substrate (6) is located on the light-incident surface of the light guide plate (5), the light guide dots (7) are disposed on the light guide surface of the light guide plate (5), and the optical film is disposed on the light-emitting surface of the light guide plate (5), characterized in that: The LED lamp (2) is arranged on the substrate (6) according to the method of claim 1 or 2.

4. The side-lit backlight module according to claim 3, characterized in that: The arrangement density of the light guide dots (7) increases in a gradient from the direction away from the light source side. At the same horizontal position, the density of the light guide dots (7) in the area directly opposite the LED lamp (2) is lower than the density of the light guide dots (7) in the area directly opposite the middle of the two adjacent lamps.

5. The side-lit backlight module according to claim 3, characterized in that: The light guide plate (5) is a wedge-shaped light guide plate (5), with the thickness of the light-incident side being greater than the thickness of the light-outcident side; and the light-incident surface of the light guide plate (5) is provided with a microprism array or a V-cut microstructure.

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