CN1612019A - Back light system and its manufacturing method - Google Patents

Abstract

The invention is a backlight system, comprising a frame body, a light guide plate and at least a light source, where the frame body has a concave region with a mouth upward and at least a cavity connected with the concave region, the light source is arranged in the cavity, and the light guide plate is arranged in the concave region b the buried-in ejection forming technique, thus forming an integrated structure together with the frame body.

Description

Backlight system and manufacturing method thereof

【Technical field】

The invention relates to a backlight system, in particular to a backlight system for a liquid crystal display device.

【Background technique】

Due to the advantages of lightness, thinness, and low power consumption, liquid crystal display devices are widely used in modern information equipment such as notebook computers, mobile phones, and personal digital assistants. However, since the liquid crystal itself does not have luminous properties, it is necessary to provide a backlight system for it to realize the display function.

Please refer to FIG. 1 , which is a structural schematic diagram of a backlight system in the prior art. The backlight system 1 includes a light guide plate 4 , a light source 5 , a light source cover 6 , a reflection sheet 7 and a frame 8 . The light guide plate 4 includes two opposite light incident surfaces 4A, a light exit surface 4B, a bottom surface 4C and a plurality of side surfaces (not marked), the bottom surface 4C is provided with a plurality of dots 9, and the function of the light guide plate 4 is to guide the light source 5 The light emitted is emitted from the light exit surface 4B to improve the uniformity of the brightness of the liquid crystal panel (not shown); the light source 5 is arranged relative to the light incident surface 4A of the light guide plate 4 and emits light to the light guide plate 4, which can be a cold cathode Fluorescent lamps (Cold Cathode Fluorescence Lamp, CCFL), light-emitting diodes (Light-Emitting Diode, LED) or electroluminescent lamps (Electroluminescent Lamp, EL); the reflective sheet 7 is arranged between the bottom surface 4C of the light guide plate 4 and the frame body 8, Its function is to reflect light from the bottom surface 4C of the light guide plate 4 to enhance the light output brightness of the backlight system 1; the frame body 8 is generally a polymer resin material, and its main function is to protect the light guide plate 4, the reflection sheet 7 and the light source 5, etc. components.

The backlight system 1 is assembled by a light guide plate 4, a light source 5, a light source cover 6, a reflector 7 and a frame 8. In addition, U.S. Patents No. 6,163,350, No. 6,502,945, No. 6,513,943, No. 6,590,626 and No. 6,593,980 The disclosed backlight system is assembled from components such as a light guide plate, a light source, a light source cover, a reflector, and a frame.

However, the above-mentioned assembled backlight system is mainly assembled by manual operation, and the assembly process is complicated, which consumes man-hours and labor costs. Moreover, there are instability and differences in proficiency in manual operations, so large tolerances need to be reserved between components. After assembly, there is a large gap between the components. When light travels between the components, light leakage occurs in the gap between the components, resulting in low brightness of the LCD panel and affecting product performance. Although in actual engineering, mechanical automation is used instead of manual operation to reduce the reserved tolerance, but it has not completely solved the problem of low light output brightness of the backlight system panel caused by light leakage.

【Content of invention】

In order to overcome the defects of low light emitting brightness, complex structure and high cost of the backlight system panel in the prior art, the present invention provides a backlight system with simple structure, high light emitting brightness and low cost.

The present invention also provides a manufacturing method of the above-mentioned backlight system.

The technical solution adopted by the present invention to solve the technical problem is to provide a backlight system, which includes a frame body, a light guide plate and at least one light source, the frame body has a concave area with an upward opening, and at least one The cavity, the light source is set in the cavity, wherein the light guide plate is set in the concave area by using embedded injection molding technology, so as to form an integrated structure with the frame.

The manufacturing method of the backlight system of the present invention includes the following steps: providing a light guide plate, placing the light guide plate into a mold; injecting molten frame material into the mold, curing the frame material, and forming the frame and the light guide plate The integrated structure forms at least one cavity on the frame body opposite to the light guide plate; takes out the frame body and the light guide plate; and sets at least one light source in the cavity of the frame body to form a backlight system.

Compared with the prior art, the advantage of the backlight system of the present invention is that: the embedded injection molding technology is adopted, and the frame body and the light guide plate form an integrated structure, so there is no gap between the components, which can effectively reduce or eliminate the light leakage phenomenon, and the liquid crystal panel emits light. The brightness is improved; the frame body is made of high-reflectivity materials, so there is no need to use reflectors and light source covers, the structure is simple, and the cost is reduced.

【Description of drawings】

FIG. 1 is a schematic structural diagram of a backlight system in the prior art.

Fig. 2 is a perspective view of the backlight system of the present invention.

Fig. 3 is a cross-sectional view along III-III direction of the backlight system of the present invention.

FIG. 4 is a flow chart of the manufacturing method of the backlight system of the present invention.

【Detailed ways】

Please refer to FIG. 2 and FIG. 3 together, which are schematic structural diagrams of the backlight system 2 of the present invention. The backlight system 2 includes a light guide plate 21 , a frame body 22 and a plurality of light sources 23 . The frame body 22 is box-shaped, which includes a lower surface 221, a plurality of side surfaces 222 intersecting with the lower surface 221, and an upper surface 223 opposite to the lower surface 221, and the upper surface 223 is provided with a concave area with an upward opening. 224 and a plurality of cavities 225 connected to the concave region 224, the material of the frame body 22 is a highly reflective polycarbonate (Polycarbonate, PC) material with a reflectivity greater than 95%, such as MitsubishiHPR3000, GE BFL2000, etc.; light guide plate 21 is set in the concave area 224 and forms an integrated structure with the frame body 22, which includes a light incident surface 211, a light exit surface 212 adjacent to the light incident surface 211, and a bottom surface opposite to the light exit surface 211 213 and a plurality of side surfaces 214, the bottom surface 213 of the light guide plate 21 is provided with a plurality of light diffusion network points 215; The incident surface 211 is opposite to each other.

The light guide plate 21 and the frame body 22 form an integrated structure using an insert molding (Insert Molding) technology.

Please refer to FIG. 4 together, which shows the manufacturing method of the backlight system 2 of the present invention. First use the injection molding process to form a light guide plate 21, which includes a light incident surface 211, a light exit surface 212, a bottom surface 213 and a plurality of side surfaces 214, the bottom surface 213 is provided with a plurality of light diffusion network points 215 (step 101); The mechanical arm puts the light guide plate 21 into a mold, which includes a female mold, a male mold matched with the female mold, and a mold core between the male mold and the female mold, wherein the mold core has multiple Convex pattern, the convex pattern is a semi-cylinder, the surface roughness of the semi-cylinder is Ra<0.08um, and its convex height is consistent with the thickness of the light incident surface 211 of the light guide plate 21. When the light guide plate 21 is placed, the light guide The light incident surface 211 of the light plate 21 is in contact with the plane portion of the semi-cylindrical body, and the molten high-reflection PC material is injected into the mold, and the PC material is solidified into a frame body 22, and the frame body 22 and the light guide plate 21 form an integrated structure ( Step 102); take out the frame body 22 of the integrated structure and the light guide plate 21, and form a plurality of cavities 225 on the side where the frame body 22 and the light incident surface 211 of the light guide plate 21 are connected, and insert a light source 23 into the cavity 225 to form Backlight system 2 (step 103).

The light guide plate is made of transparent materials such as acrylic resin, polycarbonate, polyethylene resin or glass; the bottom surface of the light guide plate is provided with light diffusion points to make the light transmit in different directions in the light guide plate, which can make the outgoing light more uniform. The light-diffusing dots can be in the shape of microprisms, dots, squares, spheres, cylinders, cubes or pyramids.

Compared with the existing manual assembly backlight system technology, the backlight system of the present invention adopts embedded injection molding technology, and the frame body and the light guide plate form an integrated structure, so there is no gap between the components, which can effectively reduce or eliminate light leakage. The light output brightness of the panel is improved; the frame is made of high-reflectivity materials, so there is no need to use reflective sheets and light source covers, the structure is simple, and the cost is reduced.

Claims (9)

1. A backlight system, comprising a frame body, a light guide plate and at least one light source, the frame body has a concave area with an upward opening, and at least one cavity connected to the concave area, the light source is arranged in the cavity , is characterized in that: the light guide plate is arranged in the concave area by using the embedded injection molding technology, so as to form an integrated structure with the frame body. 2. The backlight system as claimed in claim 1, wherein the material of the frame body is a material with high reflectivity. 3. The backlight system according to claim 1, wherein a plurality of light diffusing dots are arranged on the bottom surface of the light guide plate. 4. The backlight system as claimed in claim 1, wherein the light source is a light emitting diode. 5. The backlight system as claimed in claim 1, wherein the material of the light guide plate is acrylic resin, polycarbonate, polyethylene resin or transparent glass. 6. A manufacturing method of a backlight system, comprising the following steps: providing a light guide plate, placing the light guide plate in a mold; injecting molten frame material into the mold, solidifying the frame material, and making the frame and the The light guide plate forms an integrated structure, and at least one cavity is formed on the frame body opposite to the light guide plate; the frame body and the light guide plate are taken out; and at least one light source is arranged in the cavity of the frame body to form a backlight system . 7. The manufacturing method of the backlight system as claimed in claim 6, wherein the material of the frame body is a material with high reflectivity. 8 . The manufacturing method of the backlight system according to claim 6 , further comprising a step of forming a plurality of light-diffusing dots on the bottom surface of the light guide plate, and the step is before putting the light guide plate into the mold. 9. The manufacturing method of the backlight system according to claim 6, wherein the material of the light guide plate is acrylic resin, polycarbonate, polyethylene resin or transparent glass.

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