TW200426450A - Backlight and LCD device using the same - Google Patents

Abstract

The invention is to suppress the non-uniform brightness and color of display device and to provide higher display quality. A backlight consists of a frame (3), a first diffusion plate (1) that is installed on a opening part adjacent to the frame (3), a second diffusion plate (2) that is installed between a light source (4) and the first diffusion plate, a reflection plate (7) that is installed on the bottom and side of the frame (3), and a reflection component that is installed on the second diffusion plate (2) corresponding to the light source (4) position and reflects the light emitted from the light source (4).

Description

200426450 V. Description of the invention (1) [Technical field to which the invention belongs: Ming is a display device that is used as a light source to supply a backlight source to a display device, an i-source, or a display device. It is particularly suitable for directly arranging the light source directly below the light source. Backlight and LCD using the backlight [prior art]

Dwdeli uses LED (Ught ^ out 11 ^ DlQde) or secret coffee point light source as the backlight of liquid crystal display devices and other display devices. Compared with the conventional backlight source such as bee rc: 2: light source Without the use of mercury, you can achieve high color reproducibility by using red, red, and red primary color LEDs, as well as the light ::: Qiming Temple. 3 On the one hand, using a point light source as the brightness of the display device is easier than the brightness at a position far from the point light source. 4 :: 7C degrees ^ uniformity, color unevenness does not occur, there is a problem of lowering the display level. In order to directly arrange the point light source with uneven brightness and uneven color of the backlight directly below the display panel, in the previous backlight, the frame was arranged above and below the substrate with the point light source in a predetermined manner. The first, second, and second light-diffusing sheets are supported, and one of the light-diffusing sheets: # is placed according to the fluorescent substance of the fluorescent light emitted by the light of the aforementioned point light source to suppress ^ degree unevenness. (See, for example, Japanese Patent Application Laid-Open Nos. 2000-1 3 3 0 0 (Figure 2)). ~ There are other conventional technologies. The structure of the backlight device is a diffusing light-transmitting sheet, a light-emitting element disposed behind the light-transmitting sheet, and

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200426450 V. Description of the invention (2) The surface between the light-emitting element and the light-transmitting sheet and having a substantially V-shaped cross-section is formed on the side opposite to the surface # 无 杜 ΐ Τ The cymbals of the ministry are directed toward the light-emitting element side so that the light-emitting film is arranged at a distance from each other to suppress uneven brightness and uneven color (for example, refer to JP 20 02-493 24). (Fig.})). However, the above-mentioned Japanese Patent Application Laid-Open No. 2000-1 1 3 3 0 0 (second): It is configured to have two light diffusion sheets provided above the point light source.

St. However, the first and second light diffusion sheets of this structure also have corresponding point light sources ^ 4 The brightness at the near position becomes stronger, causing uneven brightness and uneven color.

In the prior art of the above-mentioned Japanese Patent Application Laid-Open No. 2 002-49324 (figure i), f is configured to reduce unevenness in brightness between a cymbal and a light-transmitting sheet above a point light source, but two of them cannot be provided. The diffusive function of the diaphragm, so that the diaphragm and the light-transmitting film of this structure also have a corresponding increase in brightness near the point light source, resulting in uneven brightness and color unevenness. The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a backlight with a higher display level capable of suppressing uneven brightness and uneven color, and a display device using the backlight. " SUMMARY OF THE INVENTION The backlight source of the present invention includes a frame supporting the light source and having an opening at least a portion thereof; a first diffusion plate disposed adjacent to the opening of the frame; and a second diffusion plate, Disposed between the light source and the first diffusion plate; and a reflective plate disposed on the bottom and side surfaces of the frame;

_ 1.11 ___ — 丨 丨 丨 丨 _ V. Description of the invention (3) _ It is characterized in that: on the second diffuser plate, a shape-reflection member is arranged to correspond to the light source 1 and has one of the following functions-f issued The convex portion is disposed on the surface corresponding to the aforementioned light source and reflects the light emitted by the aforementioned light source, and is arranged to diffuse the position toward the forward source, and is disposed on the surface corresponding to the aforementioned light source and π = the light source surface; The surface of the concave plate; the concave and convex portion is tight and scattered: into: the surface of the aphid toward the aforementioned "wide diffuse plate". [Embodiment] Implementation Mode 1 The cross-sectional view of the backlight source according to Embodiment 1 of the present invention according to Embodiment 1 of the present invention is shown in Figs. 1 to 4. Fig. 1 is the other figures 2 to 4 of the embodiment 1 of the invention. Fig. 1 is the first diagram. At least a part of the upper surface of the display is formed below. The frame 3 supporting the point light source 4 is connected to the first diffuser.丨. In order to block the opening, the sweat portion is adjacent to the diffuser plate 1 and the point light source 4, and the disc = the second diffuser plate 2 is between the first diffuser plate 1 and the second diffuser plate 2 and the plate 1 interval. The first material is a milky white material having a concave-convex shape on the surface or the early surface, or a diffuser plate 1 and a second diffuser plate 2 that have a light diffusion function. First expansion The supporting member 6 is installed at the ϋ: the supporting member 6 and the frame 3 to support the building. The number of sides of the moon is wide; the approximate center of the moon light source. And 'on the frame 3 line, < on the second side', a reflecting plate 7 is arranged to reflect the light emitted by the point light source 4 and the position of the reflecting plate 7 corresponding to the point light source 4 is configured. 4 light is introduced into the backlight. And, in the second expansion 2066-6288-PF (N2) .Ptd page 8 200426450 V. Description of the invention (4) The position of the point light source 4 on the surface of the diffuser plate 2 opposite to the point light source 4. The reflecting structure: the reflecting member 5 is formed in a corresponding printing method, and it can also be formed in the shape g, and can be attached to the right after the wind i after the second diffusion plate 2 is molded. The reflective structure of the adhesive force is the surface facing the point light source 4 or the second surface 2), as shown in Figure 1, regardless of the position corresponding to the point light source 4, the surface of the plate], as long as To form an efficient reflection, it is preferably as follows: In order to increase the light emitted by the point light source 4. According to the above structure, the second diffuser plate 2 in the area of the point light source 4 is not formed first, and the adjacent point light source 4 is reflected by the secondary reflection member 5 and is not reflected. The second reflecting plate 7 reflects repeatedly, and enters the bottom surface of the second diffuser plate = 3. Therefore, the light is not concentrated in the pair of the second diffuser plate 2 ". According to the setting 'W, the light is dispersed. As a result, after the neighboring bits of == 4 entered the second diffuser plate 2 and the light rays from the first diffuser plate x were scattered, the light emitted from the "wide diffuser plate" was unevenly distributed. It is expanded to become uniform brightness. ☆ Sentence Father Arrives 1 s = Zhebo / Xiongming Picture 2 to Picture 3. In Figures 2 to 3, the same components as in Figure 1 are marked with the same symbols: Brother to Figure 3 are not ancient, and there is a difference in the state of the ice. In FIG. 2, there is a reflecting member 5 in FIG. 2. In the second drawing, the convex portion 8 is formed on the surface of the diffuser plate 2 opposite to the point light source 4, and the concave portion 9 is integrally formed in FIG. 3. The second diffusion plate; = the surface of the small expansion board 1 and corresponds to the position of the point light source 4. According to the structure shown in Figure 2 or Figure 3 above, you can skip the picture i Page 9 2066-6288-PF (N2) .ptd 200426450

V. Description of the invention (5) The reflecting member reduces the manufacturing cost and improves the reliability, and the light emitted by 4 passes through the convex portion 8 or the concave portion 9 without direct ugliness. Or in Figure 3, there are two straight lines =-Light knife shot out 'so < to suppress the light from focusing on the corresponding point light and nearby. As a result, the light emitted from the point light source 4 enters the second extension 2 and arrives. From the time when the first diffusion plate 1 is emitted, it is further diffused, and the emitted light is suppressed in uneven brightness and uneven color: uniform shell degree. Next: the fourth figure is explained. In the fourth figure, The same components / knives in Fig. i to Fig. 3 are marked with the same symbols, and the differences are explained. Fig. 4, the reflecting member 5 or ^ ㈣ formed by the second diffusion plate 2 of rank 1 to 3 Or the concave portion 9, but on the surface of the second diffusion plate 2 opposite to the 丨 diffuser plate, the concave-convex portions 10 are densely formed near the position corresponding to the point light source 4, and the concave-convex portions 11 are scattered away from the corresponding point. The far position of the light source 4. According to the structure of FIG. 4, the reflecting member of FIG. 丨 can be omitted, and the manufacturing cost can be reduced. Reliability can be improved, and dense projections and depressions 10 do not directly emit from the second diffuser plate 2 but scatter the light near the position corresponding to the point light source 4 at a time, for example, in the horizontal direction on the paper as shown in Fig. 4 Therefore, it is possible to suppress light from being concentrated near the position corresponding to the point light source 4 and achieve the same effect as in the above-mentioned FIGS. 1 to 3. In addition, in FIG. 4, it is shown that the uneven portions 10 and 11 are formed on the second diffuser plate 2. The situation on the surface facing the diffuser plate 丨 can achieve the same effect even when it is formed on the surface facing the point light source 4 on the second diffuser plate 2. Also, in the fourth figure, the uneven portion 1 is shown 〇Densely formed at corresponding points

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200426450 V. Description of the invention (7) And the shape and structure of the reflecting plate can also be independently applied to backlights of various implementation types. In this case, the shape and structure of the reflecting plate can be used to disperse the light emitted from the point light source 4. Light can be more diffused by two diffuser plates, reducing uneven brightness and uneven color. In addition, FIG. 4 shows that the shape of the reflection plate 7 includes convex portions at the bottom center portion and the peripheral portion of the bottom surface of the frame 3 (a region where light emitted from a point light source is relatively small), and the bottom portion and the peripheral portions. (The area where the point light source emits a relatively large amount of light) has a recessed portion adjacent to the bottom surface, but it is not limited to this. 'As long as the light emitted from the point light source is directed toward the opening of the housing', it may be emitted from the point light source. A convex portion may be formed in a region with a small amount of light, and a concave shape adjacent to the bottom surface of the frame body may be formed in a region with a relatively large amount of light emitted from the point light source. ° Also, in Figures 1 to 4, the distance between the point light source 4 and the second diffuser plate 2 shown in Figure 丨 is L1, and the distance between the second diffuser plate 2 and the second diffuser plate = L2 Because of the relationship between LI SL2, it can more surely suppress uniformity and color unevenness. In this embodiment, the distance between L1 and L2 is: ;; the position of the diffuser 1 and the second diffuser is the center point in the thickness direction, and the position of the point source 4 is the LED light emitting element (Ic) of the point light source 4 )s position. Compare L with L1 and L2 with less than L1.

The light can be sufficiently diffused between the plates 2 and as a result, unevenness in real production and unevenness in color can be more surely suppressed. In addition, regarding L1, especially the case of using a reflective structure (the case of the figure!) 'Because the setting is small, the reflective member 5 of the light-shielding member can also be formed small or can be attached. Can increase the brightness of the backlight 'so it is best to achieve

200426450

V. Description of the invention (8) The relationship of L 2.实施 式 2 承 #: ί 第 5 图 5 The embodiment 2 of the present invention. FIG. 5 is a cross-sectional view of the backlight source of the second mode. In Figure 5, the same symbols as those of the Ming structure are indicated by the same symbols, and the differences are explained. The structure of the second and fourth oblique two figures 1 'On the second diffuser plate 2, the uneven portion 2 is formed on the surface facing the first diffuser plate 1 to form a smooth surface. There is no unevenness on the face of heading point 4

With this structure, the surface reflects the light emitted by the point light source 4 even on the surface where the reflecting member 5 is not present near the reflecting member 5 disposed opposite to the second diffuser plate 2—partially. Back and forth with the reflecting plate 7 arranged on the bottom surface of the frame body 3:, can reduce the concentration of light near the position corresponding to the point light source 4. As a result, the light emitted from the source 4 enters the second diffuser plate 2 to the first diffuser plate! The light emitted is further diffused, and the light emitted from the first diffusion plate 1 is suppressed from uneven brightness and color unevenness, and becomes uniform brightness.

A light source unit 4 according to the above-mentioned embodiment 1 and this embodiment, as shown in FIG. 6, constitutes a line of light source units 7 arranged on the circuit substrate 16 and is held on the bottom surface of the frame 3. Fig. 6 is a diagram illustrating the arrangement of the point light sources 4 held in the frame body 3 = perspective view. 'The first diffusion plate 1, the second diffusion plate 2, the reflection plate 7, the support member 6, and the like are omitted. In the light source unit 17, by adjusting the arrangement intervals of the arrangement directions of the plurality of point light sources 4, an arbitrary brightness distribution can be easily obtained in the X direction shown in FIG. 6. For example, as shown in FIG. 7, by using the point light source 4, the central part in the X direction is dense, and the end part is evacuated.

200426450 V. Description of the invention (9) The light source unit 17 allows the luminance distribution in the χ direction of Fig. 6 to be as shown in Fig. 8 & At the end, the degree is high, which can present a high-level display. Therefore, there are 3 areas where the point light source 4 is evacuated. Because of the large distance between the light sources, uneven brightness and uneven color tend to occur particularly near the point light source 4. Therefore, due to the increase in the thickness of the device, the distance between the point light source 4 and the exit surface is increased to promote the mixing of the light emitted from each point light source 4 and it is necessary to change the level of f. However, in the implementation mode and the present embodiment and the liquid crystal display device, the use of the second diffuser plate 2 can promote: political and reflective and can be taken out of the fully mixed photometric size without the need for a large heart, and the brightness can be easily reduced. Uniform, color is not equal to the point light source of the above-mentioned besch type 1 to 2, using LED, you can use the light source and the second point of the blue light and green light, the first point of the third What constitutes it. It emits monochromatic light iLE of red, grain (G), and monitor (B)]), compared with LEDs that emit white light, it has higher luminous efficiency, and because of adjustment of color filters and light sheets for liquid crystal display devices (color h Iter) 's red, green, and blue transmission characteristics and LED's emission spectrum (spectra) can be used to obtain a display with high color reproducibility. Therefore, it is necessary to use the three point light sources in combination. Embodiment 3 The embodiment 3 of the present invention will be described with reference to FIG. 9. Fig. 9 is a cross-sectional view of a backlight source according to an embodiment 3 of the present invention. In Fig. 9, the same components as those in Figs. I to 8 'are marked with the same symbols, and the differences are explained. Figure g, instead of using a point light source as the light source as in Figures 1 to 8, the display is @

200426450 V. Description of the invention (10) = the case of a linear light source 13 such as an electrode. The linear light source 13 is received by the bottom surface of the frame 3-and the diffusion sheet 14 is formed between the u-th diffuser plate ι and the linear light source 邻接 adjacent to the opening formed by at least two of the upper surfaces of the frame 3. This indicates that the thickness of the diffusion sheet is about 0.05 to 0.30 legs. For the support, for example, two 14 support plates 15 'made of transparent acrylic resin or the like are used. The support member 6 and the frame 3 support the diffusion sheet 14 and the support plate i 5. With the above-mentioned structure, it is possible to display a display with a high display level even if it is the same as the above-mentioned embodiment, which can suppress the production of two or two. Uneven redundancies, uneven colors, and hu-qi:;, I ΐ the conventional implementation type 'shows that the diffusion sheet and the support plate constitute the diffusion plate of the implementation modes 1 to 2 described above, even with this ^ =逵 5 If it is composed of diffuser sheet * branch floor, of course, it is unnecessary to achieve the same effect. The 1 plate does not specifically include centimeter 柞 糸, 7 sibetal 1 heart extension and cabinet carving Φ 栲, and at first glance, as long as it has a rigid member that can be supported, it can also be f, even with diffusion The same thin member does not have the following external configuration to me, 々 月 尤 / 原, and the gap corresponding to the opening substrate formed in the frame in the frame #? The middle lambda mixing cage is called "J" and is insulated in 2 pieces.

The combination of dry-grade high-quality / Japanese liquid-holding liquid-day liquid-day plate can obtain a liquid crystal display device of the county I.卞 ,,,! D and even for the above-mentioned implementation modes 2 and 3, as long as the distance between the above-mentioned Yugan second diffusion plate and the expansion plate is reached, and the relationship of L1 is,

200426450 V. Description of the invention (11) As in the first embodiment, uneven brightness and uneven color can be reliably suppressed. In addition, the above-mentioned embodiments 1 to 3 describe the case where the light source is supported by the bottom surface of the frame, but it is not limited. The case where the light source is supported by the side of the frame can also be achieved by the reflection member and the convex portion of the above-mentioned embodiment. Any one of the concave portion, the concave portion, and the concave and convex portion is formed at a position of the second diffusion plate that is most likely to be affected by light emitted from the light source, and the same effect as that of the above embodiment can be achieved. The above description relates to the display device of the above-mentioned embodiment using liquid crystal, but it is not limited, and even if it is applicable to all display devices provided with a so-called backlight source having a light source behind the display surface, of course, it has no effect. ❿ According to the present invention, since a backlight used in a display device can suppress uneven brightness and uneven color, it can exhibit extremely high display such as display.

2066-6288-PF (N2) .ptd Page 16 200426450 Brief Description of Drawings Figure 1 is a cross-sectional view of a backlight source according to embodiment 1 of the present invention. FIG. 2 is a cross-sectional view of another backlight source according to Embodiment 1 of the present invention. FIG. 3 is a cross-sectional view of another backlight source according to Embodiment 1 of the present invention. FIG. 4 is a cross-sectional view of another backlight source according to Embodiment 1 of the present invention. FIG. 5 is a cross-sectional view of a backlight source according to a second embodiment of the present invention. Fig. 6 is a perspective view illustrating the arrangement of a point light source according to the second embodiment of the present invention. FIG. 7 is a perspective view of a light source unit according to a second embodiment of the present invention.

FIG. 8 is a schematic diagram of the brightness distribution in the array direction of the point light sources in which plural backlight sources are arranged in the second embodiment of the present invention. FIG. 9 is a sectional view of a backlight source according to a third embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ~ 1 diffuser plate; 3 ~ frame body; 5 ~ reflection member; 7 ~ reflector plate; 9 ~ recessed part; 11 ~ concave part; 1 ~ 3 ~ line light source; 1 ~ 5 ~ support plate; 1 ~ 7 ~ light source unit L1 ~ 2nd diffuser plate and L2 ~ 1st diffuser plate and 2 ~ 2nd diffuser plate; 4 ~ light source; 6 ~ support member; 8 ~ convex part; 10 ~ uneven part; 1 ~ 2 uneven part; 1 4 ~ Diffuser; 16 ~ circuit board; distance between light sources; distance between second diffuser.

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Claims (1)

200426450 VI. Scope of patent application 1 · A backlight source, including: a frame body, supporting light source, and a portion; at least a part of the above has an opening 1 diffuser plate, and a neighboring diffuser 2 diffuser plate is arranged in front of the :: frame An opening portion of the body; and, between the light source and the first diffusion plate; a reflection plate disposed on the frame, wherein: the bottom surface and the side surface of the M-shaped, on the second diffusion plate, a reflecting member, Arranged at / 1% + with any of the following · The light emitted by the source;, f should reflect the position of the light source to reflect the aforementioned light convex portion, placed at p, +, and out of the light, and set the position to Diffusion of the aforementioned light source is straight, and the opposite direction of the light source is described, and the light source recessed portion is disposed at the speaking position ^ Γ, +, and! The surface of the diffuser plate; The position of the light source just described is set to face the aforementioned concave-convex portion, and a ^ ^ ^ ^ ^ surface is formed tightly and sparsely. From the opposite to the first description of the diffuser plate 2. If the member shot in item 1 of the scope of the patent application is in the aforementioned second source, the above-mentioned inverse πL, 丄, expansion board, corresponding to The position of the light source is formed or attached to a surface facing the light source. 3. If the second diffuser plate of the scope of the patent application, or the backlight, the surface facing the light source is a non-slip surface. As described in any one of claims 1 to 3 of the scope of application for a patent, wherein the reflecting plate has a concave-convex portion on the bottom surface of the frame. ", '2066-6288-PF (N2) .ptd page 18 200426450 VI. Patent application scope 52. The backlight as described in any one of the patent application scope items 1 to 4, except the first diffusion The plate and / or the second diffusion plate are formed by combining diffusion. 6 、 Same board 6 · As in the first patent application, where the aforementioned light source is a point light source. The backlight according to any one of 5 to 7. The backlight according to item 6 of the scope of patent application, wherein in the arrangement direction of the point light sources, the respective arrangement intervals of the point light sources are at the center For tightness, the ends are evacuated. As described in t, the backlight according to any one of items 1 to 7, wherein the distance u between the second diffusion plate and the light source is described, and the distance between the first diffusion plate and the second diffusion plate is described. The distance of 12 satisfies the relationship of u gL2. t A liquid crystal display device, comprising: a backlight source, as described in any one of claims 1 to 8 of the scope of patent application; and a liquid crystal panel, which is disposed on the outside of the aforementioned casing and correspondingly formed in the aforementioned casing. The position of the opening, and the liquid crystal is held between the two insulating substrates.