TWI247177B - Structure and method for increasing the brightness in the dark area of a backlight module - Google Patents

Abstract

The present invention provides a structure and method for increasing the brightness in the dark area of a backlight module. Cutting the corners of the light guide plate of the backlight module to provide an extra space for leaking light into the dark areas. Thus, the brightness in the dark areas could be enhanced and the whole light output of the backlight module will become more uniform.

Description

1247177

I. [Technical Field] The present invention relates to a structure and a method of a backlight, in particular, relating to a portion close to a lamp electrode to improve light output uniformity of a backlight module. [Prior Art] The dark area of the corner is brightened by a chamfered area of the light guide plate in the backlight module, and by means of the chamfered area.

The components used to provide the back light source can be applied to products such as display H, cell phone panels, film scanners, and slide projectors to provide a uniform surface light source output. A schematic diagram of the three-dimensional structure of the side-lit backlight module of the cold cathode tube can be referred to the first A diagram. The backlight module 100 is mainly composed of a light guide plate (Light Guide)

Plate) 101, a reflective member (Refiecti〇n Film) 103, a symmetrical L-shaped cold cathode tube (L-shape CCFL) 105, a diffusion film (Diffusion Film), and an optical film (Optical film) L〇9 and the frame 1 1 1 , 1 1 3 for arranging the above elements. L type cold cathode tube

The 1 0 5 system is mounted around the light guide plate 1 〇1, so that the generated light can enter the light guide plate 101 in an edge 1 ight manner, and guides the direction of light scattering by the light guide plate 1 〇1 and The fit of the reflector 1 0 3 mounted on the light guide plate 1 0 1 causes the light to be distributed to the upper diffuser 10 7 after being reflected and refracted to make the light distribution more uniform. On the other hand, the diffuser 1 〇 7 can be equipped with other optical films with specific functions 1 〇 9, for example, with a poly

Page 5 1247177 V. INSTRUCTIONS (2) Light-operated cymbals (Pr i sm ) to increase the directivity of the light output, and to improve the brightness of the front surface. Referring to the first B picture, it is a conventional backlight module! The upper light guide plate i i and the L-type cold cathode tube 1 〇 5 are mounted in the upper perspective view of the frame 1丨3. From the above perspective view, it can be observed that the L-type cold cathode tube i 〇 5 disposed in the opposite direction is installed around the light guide plate 1 〇1, but the L-type cold cathode tube i 〇 5 itself cannot emit light at the electrode portion. And the rubber insulation sleeve 5 is put on, so that the light output of the backlight module 100 will be in the corner portion.

The area of the near electrode (such as the circle circled by the broken line )7) produces a dark area '' with insufficient brightness, and the overall light output may be left or right or uneven. Three [Summary content]

In the background of the above invention, the backlight module is in the corner area close to the lamp pad, because of the lack of brightness, the problem of dark areas is generated, and the brightness of the dark area in the backlight module is reduced by two or two kinds. The method, the purpose of which not only creates the opportunity of the dark area in the inner light i μ light group, but also improves the plane illumination efficiency of the backlight module, so that the backlight module can have a uniform brightness structure, not: out. In another aspect, the present invention also provides a backlight module with a complete back; the light source can enter a dark area in the corner of the backlight module to improve the uniformity of the three sets of light output. On the other hand, the backlight module also

Page 6 1247177 V. Description of the Invention (3) According to the above object, the present invention provides a structure and method for improving the brightness of a dark region in a backlight module, and the light guide plate in the backlight module is adjacent to a corner of the electrode portion of the lamp tube. Cutting off, so that the light source can generate natural light leakage through the chamfering area, thereby improving the brightness of the dark area and increasing the uniformity of the overall light output of the backlight module; in addition, the invention provides the chamfering The light guide plate of the area not only can be adjusted according to the range and position of the electrode part of the actual lamp tube, but also because of the chamfered area, the heat dissipation in the backlight module can achieve better results. 4. [Embodiment] The following is a detailed description of the present invention. The description of each component in the backlight module in the following description does not include a complete description of its operation principle and assembly process. The prior art of the present invention is hereby incorporated by reference in its entirety for the purpose of the present disclosure. Further, the related drawings in the following texts are not drawn to actual scales, and their effects are only to express the features of the present invention. According to a first preferred embodiment of the present invention, there is provided a method and structure for improving the brightness of a dark area in a corner of a backlight module. Referring first to FIG. 2A, it is a schematic diagram of a three-dimensional structure of a backlight module to which the present invention is applied. The backlight module 200 is mainly composed of a flat type light guide plate 2 0 1 , a reflection member 2 0 3 , a light source 2 0 5 , a diffusion sheet 2 0 7 , an optical film 2 0 9 , and a device for arranging the above components. The frame consists of 2 1 1 and 2 1 3 . The light source 2 0 5 is selected from two symmetry

1247177 V. INSTRUCTIONS (4) The L-shaped cold cathode tube is disposed and installed around the light guide plate 2〇1, so that the generated light can enter the light guide plate 2〇1 by means of the end face illumination (this embodiment adopts one The side-input light source is incident, and the light is deflected by the light guide plate 2〇1 and the reflection member 2 〇3 is mounted under the light guide plate 2, so that the light is reflected and refracted and output to the upper side. The square diffuser 2 〇7 makes the light distribution more uniform. On the top of the diffusion sheet 2 〇 7, other optical films 209 having a specific function can be provided. Referring to FIG. 2B, the light guide plate 20 1 in the backlight module 200 and the L-type cold cathode tube 200 are mounted in an upper perspective view in the frame 2 1 3 . Therefore, the backlight module 2 〇〇 provided by the present invention can be clearly observed. One of the features of the backlight module 2 is that the light guide plate 201 is adjacent to the electrode portion of the light source 205 (not shown in the figure, because The corner surrounded by the insulating sleeve 2 15 is removed, and the position of the light guide plate 2 0 1 near the corner of the dark area (such as the circle surrounded by the broken line 2丨7) has a chamfered shape. In this way, the light emitted by the light source 2 〇5 can be naturally leaked through the chamfered area of the light guide plate 〇1, and the light in the dark area can also be reflected by the reflective member 2〇3 and then enter the light guide plate. 2〇丨The upper diffusion sheet 2 0 7 is subjected to subsequent processing; therefore, the brightness of the dark area can be complemented to make the overall light output of the backlight module uniform. In the present embodiment, the light guide plate 201 is a prismatic guide angle at a corner close to the electrode of the light source 205, but the chamfered shape of the light guide plate 2 0 1 is not limited thereto. In the range of the circle 2 1 9 circle in the second C diagram, the light guide plate 2 0 1 may also have a rounded outer shape of the rounded corner; and the other corresponds to the light guide plate 2 〇丨

1247177 V. INSTRUCTIONS (5) I. The chamfered area formed by this dark area should be able to provide the reflection member 203 and the diffusion sheet, and the concrete effect can be achieved only by the ', and the film and 2:=: The direct through structure is the heat dissipation space. Wei Wu also let the Yu Xianyi group more than 200 more than the extra? Come to laugh the third month: light; the thick side of the square source into the 0: the gas sheet 1 Μ /, while referring to the second map, its backlight The wedge 3 0 1 in the module 3 and the light source 3 0 5 are mounted in an upper perspective view in the frame 3 1 3 . By clearly observing, the backlight module 300 provided by the present invention, the second one is the electrode portion of the wedge-shaped light guide plate 310 which is close to the light source 3 〇 5 (Fig. No, because it has been insulated by the insulating sleeve 315 The corner surrounded by it is removed, μ (four)

1247177 V. INSTRUCTIONS (6) The light guide plate 3 0 1 has a chamfered shape at the position near the corner of the dark area (such as the circle circled by 3虚线9) (in this embodiment, the chamfer shape is selected. a rounded structure). In this way, the light source emitted by the light source 3 〇5 can generate natural light leakage through the chamfered area of the wedge-shaped light guide plate 301, and the light in the dark area of the corner is reflected by the reflection member 3 〇3 and enters the building. The diffusion sheet 3〇7 above the type of light guide plate 3〇1 is subjected to subsequent processing; therefore, the dark area can be compensated so that the overall light output of the backlight module can be uniform. It can be seen from the above-mentioned first and second preferred embodiments of the present invention that the light guide plate provided with the chamfering area of the present invention has a chamfered shape which can be a prismatic guide angle or a circular arc shape. The rounded corners or other shapes can also be formed on the flat plate type and the wedge type light guide plate, so the lamp tube used in the backlight module is linear (the four linear lamps constitute a moment) = light source, or a single linear tube), U-type, C-type, and L-type lamp's as long as the light-shielding plate can be formed near the corner or side of the electrode part of the lamp to achieve natural light leakage. The effect is to maximize the luminous efficiency of the lamp; and the invention is not limited to the side-in-the-light source mode (the light incident surface of the light guide plate has a perpendicular angle with the light output surface): For example, a direct type backlight module (light incident surface and light output of the light guide plate)

Parallel) can also be embodied in accordance with the present invention. "I, the above description of the dark area of the backlight module provided by the present invention, 3j first emits at least one light source (including linear type, U type, L plastic and C side edge 4) into a light guide plate Light entry surface (including flat and wedge)

1247177

In the light guide plate, the light can be guided by the light guide plate and then led out from the light output surface of the light guide plate. However, since the electrode portion of the lamp tube cannot emit light and is covered with an insulating sleeve, a dark area with insufficient redundancy is generated in the position of the light guide plate near the electrode portion of the lamp tube, so that the light output uniformity of the entire backlight module is lowered. Therefore, the present invention proposes to form a chamfered position in the light guide plate corresponding to the positions of the dark regions (for example, if two symmetrical L-shaped lamps are used, the light guide plate can form a pair of opposite corners near the electrode portion. If the position of the corresponding electrode portion of the light guide plate is not in the corner of the light guide plate, a groove structure can be formed on the side of the light guide plate to achieve a natural light leakage effect, and thus, the backlight mode is located. The light in the so-called dark area in the group can pass directly through the chamfering area and be diverged by reflection or direct emission (for example, by reflection or directly into the diffuser above the light guide plate), so that it can be improved. The brightness of these dark areas in the backlight module can increase the overall light output uniformity.

Page 11 1247177 Brief description of the diagram V. [Simple description of the diagram] The first diagram A is a schematic diagram of the three-dimensional structure of the conventional backlight module. The first B is a top perspective view of the light guide plate and the light source in the conventional backlight module. Figure 2A is a perspective view showing the structure of a backlight module provided by the first preferred embodiment of the present invention. The second B is a top perspective view of the light guide plate and the light source in the backlight module in the first preferred embodiment. The second C is a light guide plate with a rounded corner structure and an upper perspective view of the light source in the backlight module. The third A is a schematic perspective view of a backlight module provided by the second preferred embodiment of the present invention. The third B is a top perspective view of the light guide plate and the light source in the backlight module in the second preferred embodiment. Component Symbol: 100 Backlight Module 101 Light Guide 103 Reflector 105 Light Source 107 Diffuser 109 Optical Diaphragm 111 Frame 113 Frame

Page 12 1247177 Schematic description 115 Insulation sleeve 117 Location of dark area 200 Backlight module 201 Light guide plate 203 Reflector 205 Light source 207 Diffusion sheet 209 Optical diaphragm 211 Frame 213 Frame 215 Insulation sleeve 217 Leading profile 219 Guide Rounded shape 300 Backlight module 301 Wedge light guide 303 Reflector 305 Light source 307 Diffuser 309 Optical diaphragm 311 Frame 313 Frame 315 Insulation sleeve 319 Leading round shape Φ

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Claims (1)

1247177 -----One case number 93114949 Year Month_Amendment__ VI. Apply for a patent ^ -^~'^ It consists of two linear lamps that are oppositely arranged. The backlight module of claim 1, wherein the light source is composed of four linear lamps, and is disposed around the light guide plate. 9. The backlight module of claim 1, wherein the light guide plate adopts a direct type light source incident mode. 10. The backlight module of claim 9, wherein the light source is composed of a plurality of linear tubes arranged in parallel. The backlight module of claim 9, wherein the light source is composed of at least one U-shaped tube. The backlight module of the light guide plate 12 is a wedge type light guide plate. The light source 13 is a backlight module as described in claim 2, which is composed of a straight-line type lamp. 1 4 - The backlight solar panel according to claim 1 is disposed on one side of the light output surface. The light refracted by the reflection can be reflected back into the light guide plate. , from the side of the 1247177 μ _-- case number g3114fug L 』 · - - 六 六 六 六 六 六 六 六 六 六 六 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光 背光It is a cold cathode tube. 16) A method for improving brightness of a dark area in a backlight module, comprising: emitting at least one light source into a light guide plate, and guiding the light through the light guide plate to be derived from a light output surface of the light guide plate; Wherein, the chamfered area of the light guide plate has a complete cross section, and the light is evaded by the chamfered area to avoid the light guide plate, and is dispersed by means of reflection or direct emission, thereby improving the cutting The brightness of the corner area. 1 7· The method for improving the brightness of the dark area in the backlight module as described in claim 16 of the patent application, wherein when the light source is a lamp, the chamfering area is corresponding to and close to the light guide plate The area of the electrode portion of the tube. "曰~1 8 · The method for improving the dark area in the backlight module as described in Clause 16 of the patent application is 'degree of the angle, wherein the angle outside the chamfered area is a lead angle structure. 3 ° ° 70 1 9 · A method for improving the darkness of a dark region in a backlight module as described in claim 16 of the patent application, wherein the ridge is a rounded corner structure outside the chamfered area. The method for improving the brightness of a dark region in a backlight module, wherein the chamfered region/transparent structure can be achieved by forming a recessed trench structure on the light guide plate. 1247177 _ Case No. 93914949_年月日日__ VI. Patent Application Range 2 1. The method for improving the brightness of the dark area in the backlight module as described in claim 16 of the patent application scope, further includes A reflector is disposed on one side of the light output surface such that light refracted from the side can be reflected back into the light guide plate. Page 17