JP2012234765A - Double-faced emission display panel by one sheet of light guide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the following problem: when faces are made to emit light with a light guide plate and an edge light, one sides of the light guide plate may be made back-to-back or a light guide plate for double-faced emission and the edge light may be used, but in that case, material expense is about doubled and total cost rises accordingly.SOLUTION: A transparent plate is arranged and fixed to an optical conversion part side of an ordinary light guide plate. When light of the edge light is converted at the optical conversion part, it is dispersed in all directions. If an optical diffusion plate each is provided at a surface and a rear face of the light guide plate, a double-faced light-emitting plate is realized. In this case, just one light guide plate is used, and one sheet of edge light is used. A material to be used is just one sheet portion plus a transparent plate, so that a low-cost double-faced light-emitting plate can be realized with the minimum material cost.

Description

With the development of LED technology, strong light will be generated. Furthermore, it is possible to realize wide surface light emission by changing the direction from the light conversion portion of the light guide plate by utilizing the amount of light. The present invention has been realized by combining the LED edge light manufacturing technology, the conversion efficiency of the light conversion part, and the installation structure of the light diffusing plate that receives the light on both sides.

The present invention is a light emitting plate using an LED edge light and a light guide plate. By improving the light emission efficiency of the LED, it becomes possible to generate a high amount of light with a small light source. The surface can emit light. As a result, a large display panel can be manufactured, and a large and bright display panel can be realized with less power consumption.

In the conventional double-sided light emission by the edge light, as shown in FIG. 2, single-sided light emission is used back to back as shown in FIG. 2, or only double-sided light emission is used as shown in FIG. As a result of repeated trial manufacture and experiment aiming at lighter and lower cost, a double-sided light emitting plate was realized with one light guide plate and one edge light of the present invention.

  The self-luminous display panel using LED edge lights consumes significantly less power than conventional interior lighting signs using fluorescent lamps. In addition, a structure that uses the least amount of power was achieved, with a 35% reduction in power consumption compared to the double-sided light guide plate.

JP 2010-147190 A JP 2009-289506 A JP2008-166120A JP-A-2005-050630

When light is emitted from both sides with a light guide plate and an edge light, as shown in FIG. 2, there is a method of emitting light with the single-sided light emitting plates fixed back to back. In this case, the weight doubles and the thickness doubles.

As shown in FIG. 3, there is a light guide plate and edge light dedicated to double-sided light emission. It can be realized by combining two light guide plates, one reflection sheet, and one dedicated edge light to realize a double-sided light emitting plate, but the material cost to be used increases and the cost increases accordingly.

There are double-sided light guide plates and dedicated edge lights, but the edge lights are arranged in two rows, the number of LEDs is 1.5 to 2 times, and the power consumption increases in proportion to the number. LED edge light that reduces power consumption, but goes against energy-saving purposes.

A transparent plate is arranged and fixed to the light conversion part surface of a normal light guide plate. When the light of the edge light is converted by the light conversion part, the light is dispersed in all directions. If light diffusion plates are provided on the front and back surfaces of the light guide plate, a double-sided light emitting plate can be realized. In this case, there is one light guide plate, and one edge light is used. The material used is just a transparent plate for each sheet, and it is completed with a minimum increase in material costs.
Therefore, as shown in FIG. 4, a thin and lightweight double-sided light emitting plate according to the present invention can be realized.

The double-sided light emitting plate with a combination of one light guide plate and one edge light greatly reduces the material cost to use compared to the double-sided light emitting plate with two light guide plates.
As shown in Table 1, the surface illuminance is reduced by about 29%, but the cost can be reduced by about 50%. The cost is important because the brightness can be gradually improved by improving the performance of the LED. In the actual market, it is not necessary to produce an illuminance higher than the optimum brightness. Therefore, the reduction of the manufacturing cost according to the present invention is very effective.

A double-sided light-emitting plate with one light guide plate and one edge light is very effective in reducing power consumption. Compared with the conventional double-sided light emitting plate, the power consumption is greatly reduced. As shown in Table 2, the power consumption is reduced by about 50% compared to the double-sided single-sided light emitting plate, and it is reduced by about 28% compared with the case of exclusive use for double-sided light emission. This reduction in power consumption is an important factor that meets social needs.

The combination of one light guide plate and one transparent plate sandwiches the light conversion part from both sides, resulting in a robust structure that is not susceptible to external influences. Depending on the application, messy handling is expected, but there is little risk of breakage or dropout of the light conversion section. Exactly, a light conversion part is arranged at the center of the transparent plate, and light is emitted from both sides of the transparent plate. For this reason, double-sided display can be performed simply by placing necessary display objects on both sides.

The following table is a measurement of the A side of a single-sided light emitting plate, a double-sided initial light-emitting plate, and a single-sided double-sided light emitting plate, and the light emission conditions are as follows.
Voltage: 24V
Light guide plate: 5mm
Light guide plate size: 300mm x 300mm
LED ;; NSSW123T manufactured by Nichia Corporation

The effect of the present invention contributes to the reduction of energy consumption and production cost. In particular, the reduction of energy consumption meets the social needs, and the spread of the present invention seems to contribute to energy saving.

Figure 1 shows the front and back surfaces of a surface light-emitting plate Figure 2 shows a double-sided light-emitting plate with single-sided light-emitting plates back to back Figure 3 shows a light-emitting plate dedicated to both sides Fig. 4 is a structural diagram that emits light from both sides with a single light guide plate. FIG. 5 is an enlarged view of a structure in which light is emitted from both sides with a single light guide plate.

In the implementation of the double-sided light emitting display plate, since the light diffusion plates on both sides emit light uniformly, a light-transmitting film is attached to the surface for display. Examples of the light transmissive film include a color film, a silk-printed film, and an ink-jet printing film. By shining light from the back side of the light transmissive film, a display surface with visibility and design is realized.

The light conversion section provided on the light guide plate normally performs dot conversion to perform light conversion. In some cases, instead of dot printing, digital cutting or laser cutting is applied to change the light. The dot shape has a small diameter near the light source and a large diameter as the distance from the light source increases, and the light conversion efficiency is changed to adjust the light emitting surface to be uniform.

FIG. 1 shows the surface state of the double-sided light emitting plate, and the display on the A side (front) and the display on the B side (back) can display completely different contents. The illuminance is almost the same, and both sides can be displayed with a single issuing board.

FIG. 4 is a cross-sectional view of a structure that emits light on both sides with a single light guide plate. The light emitted from the light conversion portion provided on one side of the light guide plate is emitted with substantially the same amount of light to the front and back surfaces of the light guide plate. The light is dispersed by the light diffusion plate on the front surface and the light diffusion plate on the back surface to create a uniform light surface. A display object is attached to the surface of the uniform light surface to form a double-sided display board.

FIG. 5 is an enlarged view showing the direction of the LED light, the light traveling in the light guide hill, and the light dispersed from the light conversion unit to both sides. The light that has traveled in the light guide hill is dispersed on both sides by the light conversion section, and is dispersed by a light diffusing plate provided at the tip of the light to create a uniform light surface.

Fig. 2 shows a device that issues both sides of a single-sided light-emitting plate back to back. It requires twice as many members as the single-sided member and twice as many LED edge lights. FIG. 3 shows a light-emitting plate structure designed exclusively for double-sided light emission. Although slightly simplified compared to FIG. 2, two light guide plates and two rows of LED edge lights are required. As shown in FIG. 4, the present invention is composed of one light guide plate and one LED edge light, and uses fewer members, greatly reducing production costs.

A double-sided light-emitting plate with a single light guide plate consumes very little power, and is therefore suitable for lighting fixtures and light sources that light for a long time. For example, there are a wide variety of emergency lights in buildings, emergency guide lights on highways, and guide lights in tunnels. It uses LEDs and has a single-row edge light that consumes less power, has a lower failure rate, and is easier to maintain.

1 LED
2 Light guide plate 3 Transparent plate 4 Light diffusion plate 5 Light conversion unit 6 Printed circuit board 7 Metal frame 8 Reflective sheet 10 Light traveling in the light guide plate 11 Light redirected by the light conversion unit 12 Light traveling from the light diffusion plate to the outside

Claims (3)

An LED double-sided light-emitting display board that is a light-emitting board that combines LED edge light and a light-guide plate, and allows the front and back surfaces of the light-emitting plate to emit light simultaneously by light emitted from the light conversion section of one light-guide plate. A double-sided light emitting display plate with one light guide plate and one LED edge light. The light conversion part provided in the light guide plate is sandwiched between transparent plates, suppressing uneven light conversion due to external pressure and contact, and stable 2. The LED double-sided light emitting display board as described in 1 above, which makes it possible to emit light. A transparent plate was provided to reduce the difference in illuminance between the front and back surfaces, so that the distance between the light diffusing plate on the surface of the light emitting plate and the light converting portion and the distance from the light converting portion to the light diffusing plate on the back surface were brought close to approximate values. 2. The LED double-sided light emitting display board as described in 1 above.