CN1317591C - Direct Type Backlight Assembly - Google Patents

Abstract

A direct-type backlight assembly comprises: a diffusion plate; a reflection plate connected to the diffusion plate to form a cavity; a light source arranged in the cavity; and a light guide plate arranged between the light source and the reflection plate.

Description

Direct Type Backlight Assembly

technical field

The present invention relates to a direct-type backlight assembly, in particular to a direct-type backlight assembly as follows: a light guide plate is arranged between a light source and a reflector to change the light path of the light emitted from the lower half of the light source to increase the optical efficiency .

Background technique

FIG. 1 shows a schematic structural view of a known direct-lit backlight assembly disclosed in Japanese Patent Publication Nos. 2001-059961 and 07-045114. In the known direct-type backlight assembly 100, a cavity 130 is formed by a back plate 110 and a diffuser plate 120, and a plurality of lamp tubes are arranged in the cavity 130 as light sources 140. , a reflective plate 150 is also provided; the reflective plate 150 is plated with silver, and the reflective plate 150 is stamped and bent to form a wave shape (or other various shapes) that facilitates light reflection, and then attached to the back plate 110.

Although the above-mentioned direct-type backlight assembly 100 increases the partial utilization rate of the light from the lower half of the light source 140, the light emitted from the vicinity directly below the light source 140, as shown by the arrow a, hits the reflector 150 and will be absorbed by the light source. 140 is blocked by the light source 140, but still cannot pass through the diffusion plate 120 and emit out of the direct-type backlight assembly 100, so part of the light is still wasted.

Contents of the invention

In view of this, the object of the present invention is to provide a direct-lit backlight assembly. The assembly uses a light guide plate between the light source and the reflector to change the light path of the light emitted from the lower half of the light source to increase the optical efficiency. Direct type backlight assembly.

In order to achieve the above object, the present invention provides a direct-lit backlight assembly, which includes: a diffuser plate; a reflector plate, the reflector plate is connected with the diffuser plate to form a cavity; a light source arranged in the cavity ; and a light guide plate disposed between the above-mentioned light source and the above-mentioned reflecting plate.

According to the present invention, since the light guide plate has the function of changing the light path, the light source emitted from the lower half of the light source can use the light guide plate to avoid the position of the light source, be reflected by the reflection plate, and reach the diffusion plate, and at the same time compensate for the brightness and darkness between the light source arrangement positions In addition, the present invention simplifies the manufacturing method and cost of the reflector because it does not need to stamp the reflector into a corrugated shape in the known technology.

In order to make the above-mentioned and other purposes, features, and advantages of the present invention more obvious and understandable, a preferred embodiment is specifically cited below, and in conjunction with the accompanying drawings, the detailed description is as follows:

Description of drawings

FIG. 1 is a cross-sectional view of a known direct-lit backlight assembly.

FIG. 2 is a cross-sectional view of the first embodiment of the direct type backlight assembly of the present invention.

FIG. 3 is a cross-sectional view of a second embodiment of the direct type backlight assembly of the present invention.

FIG. 4 is a cross-sectional view of a third embodiment of the direct type backlight assembly of the present invention.

FIG. 5 is a cross-sectional view of a fourth embodiment of the direct type backlight assembly of the present invention.

Symbol Description:

100, 200, 300, 400～direct type backlight assembly;

110～backboard;

120, 210, 310, 410 ~ diffusion plate;

130, 250, 350, 450 ~ cavity;

140, 230, 330, 430 ~ light source;

150, 220, 320, 420～reflector;

240, 340, 440 ~ light guide plate;

341, 441 ~ protruding part;

360～light diffusion device;

460 ~ light diffusion material.

Detailed ways

first embodiment

2 is a cross-sectional view of a direct-lit backlight assembly 200 according to the first embodiment of the present invention. A cavity 250 is formed by connecting a diffuser plate 210 and a reflector plate 220. A plurality of lamp tubes are arranged in the cavity 250 as light sources 230, wherein , a light guide plate 240 is disposed between the light source 230 and the reflection plate 220 to change the path of light.

After the light is emitted from the light source 230, the light b emitted from the upper part of the light source 230 directly passes through the diffusion plate 210 and exits the direct-lit backlight assembly 200; while the light c emitted from the lower part of the light source 230 first Entering the light guide plate 240, in the light guide plate 240, the optical path of the light c is changed, and then utilizes the reflection of the reflection plate 220, leaves the light guide plate 240, passes through the diffusion plate 210, and exits the direct type backlight assembly 200. In this embodiment, the upper surface of the light guide plate 240 is a plane.

In this embodiment, the light c is guided by the light guide plate 240 so that it deviates from the position directly below the light source 230 to prevent the reflected light from being blocked by the light source 230 , so it can pass through the diffusion plate 210 and emit the direct-type backlight assembly 200 At the same time, the light emitted from the lower half of the light source 230 can compensate for the dark bands that may be generated between the configurations of the light source 230 through the function of the light guide plate 240, so that the overall light emitting surface of the direct type backlight assembly 200 is more uniform.

second embodiment

3 is a cross-sectional view of a direct-lit backlight assembly 300 according to the second embodiment of the present invention. A cavity 350 is formed by connecting a diffuser plate 310 and a reflector plate 320. A plurality of lamp tubes are arranged in the cavity 350 as light sources 330, wherein , a light guide plate 340 is arranged between the light source 330 and the reflection plate 320 to change the traveling route of light, wherein the upper surface of the light guide plate 340 is designed as a mountain-shaped bulge between the light sources 330 according to the position of the light source 330, In this embodiment, the shape of the upper surface of the light guide plate 340 is an arc surface.

After the light is emitted from the light source 330, the light b emitted from the upper part of the light source 330 directly passes through the diffusion plate 310 and exits the direct-lit backlight assembly 300; while the light c emitted from the lower part of the light source 330 first Entering the light guide plate 340, in the light guide plate 340, the optical path of the light c is changed, and then utilizes the reflection of the reflection plate 320, leaves the light guide plate 340, passes through the diffuser plate 310, and exits the direct type backlight assembly 300.

In this embodiment, the light c emitted from the lower part of the light source 330 is guided by the light guide plate 340 to make it deviate, so that the reflected light is prevented from being blocked by the light source 330 and can be emitted through the diffuser plate 310 Direct-down backlight assembly 300; at the same time, the convex portion 341 of the surface of the light guide plate 340 is designed with a mountain-shaped bulge, and has a light-collecting effect. The output part 341 then emits through the diffuser plate 310 to leave the direct-type backlight assembly 300. Since the protruding part 341 is located between the positions of the light sources 330, and its light collecting function can form a virtual lamp tube, it compensates for the gap between the positions of the light sources in the past. The possible disadvantage of dark bands is to increase the number and density of lamp tubes to achieve the purpose of uniform surface light source.

third embodiment

In this embodiment, in order to make the light more evenly distributed to achieve effective use, a diffuser 360 can be installed between the light guide plate 340 and the reflector 320 in the second embodiment as a light diffusion device, so that the light distribution is more efficient. uniform, as shown in FIG. 4 , light c is incident on the light guide plate 340, and then incident on the diffusion sheet 360, due to the diffusion of the diffusion sheet 360, the light c is deviated, reflected by the reflector 320, and then passes through the diffusion sheet 360, The light guide plate 340 passes through the diffuser plate 310 and emits out of the direct type backlight assembly 300 .

Fourth embodiment

5 is a cross-sectional view of a direct-lit backlight assembly 400 according to Embodiment 4 of the present invention. A cavity 450 is formed by connecting a diffuser plate 410 and a reflector plate 420. A plurality of lamp tubes are arranged in the cavity 450 as light sources 430, wherein, A light guide plate 440 is arranged between the light source 430 and the reflection plate 420 to change the traveling route of the light. The upper surface of the light guide plate 440 is arranged as a mountain-shaped bulge between the light sources 430 according to the position of the light source 430. The cross-sectional shape of the light panel 440 may be a curved surface or a plane, and in this embodiment, it is a curved surface.

In this embodiment, the light-diffusing material 460 is doped in the light guide plate 440, and the light-diffusing material 460 is generally distributed directly under the lamp tube 430, and the light c emitted from the lower part of the light source 430 passes through the light guide plate. The light guide function of 440 and the diffusion function of the light diffusion material 460 make it deviate, thus avoiding the reflected light from being blocked by the light source 430, and can pass through the diffusion plate 410 and emit out of the direct-type backlight assembly 400; at the same time, the light guide plate The protruding part 441 is designed with a mountain-shaped bulge on the surface of 440, and it has a light-collecting effect at the same time. When the light enters the light guide plate 440, it is easy to concentrate the light on the protruding part 441 through light guide and reflection, and then emits through the diffuser plate 410 to leave In this direct type backlight assembly 400, since the protruding part 441 is located between the positions of the light sources 430, and its light collecting effect can form a virtual lamp tube, it makes up for the shortcomings of the dark bands that may be caused between the positions of the light sources in the past. The number and density of lamp tubes are used to achieve the purpose of uniform surface light source.

According to the present invention, since the light guide plate has the function of changing the light path, the light emitted from the lower half of the light source can use the light guide plate to avoid the position of the light source, be reflected by the reflector, and reach the diffuser plate, and at the same time compensate for the brightness and darkness between the positions of the light sources. In addition, because the present invention does not need to stamp the reflecting plate into the corrugated shape of the known technology, it simplifies the manufacturing method and cost of the reflecting plate.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore The scope of protection of the present invention should be defined by the scope of the claims of the application.

Claims (9)

1. direct type backlight assembly comprises:

One diffuser plate;

One reflecting plate, described reflecting plate is connected with described diffuser plate, forms a cavity;

Be arranged at a plurality of light sources of described cavity; And

One is arranged at the light guide plate between described a plurality of light source and the described reflecting plate.

2. direct type backlight assembly as claimed in claim 1 is characterized in that: described a plurality of light sources are fluorescent tube.

3. direct type backlight assembly as claimed in claim 1 is characterized in that: described light guide plate has a plurality of protuberances, and these protuberances are arranged at respectively between described a plurality of light source.

4. direct type backlight assembly as claimed in claim 3 is characterized in that: described light guide plate also has a plurality of arc sections, and these arc sections are located between described a plurality of protuberance.

5. direct type backlight assembly as claimed in claim 1 is characterized in that: described light guide plate directly contacts with described reflecting plate.

6. direct type backlight assembly as claimed in claim 1 is characterized in that: comprise that also one is arranged at the light disperser between described light guide plate and the described reflecting plate.

7. direct type backlight assembly as claimed in claim 6 is characterized in that: described smooth disperser is a diffusion sheet.

8. direct type backlight assembly as claimed in claim 1 is characterized in that: be doped with photodiffusion material in the described light guide plate.

9. direct type backlight assembly as claimed in claim 8 is characterized in that: described photodiffusion material concentrate be distributed in described a plurality of light sources under.

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