TWM449281U - Light guide plate structure - Google Patents

Abstract

A light guide plate structure includes a light guide plate, a first medium layer, a micro structure, a second medium layer, and a reflection layer. The light guide plate has a light exit surface and a bottom surface opposite to the light exit surface. The first medium layer is formed on the light exit surface. The micro structure is formed on the bottom surface for redirecting light inside the light guide plate to emit from the light exit surface. The second medium layer is formed on the micro structure. The refractive index of the first medium layer and the refractive index of the second medium layer are less than the refractive index of the light guide plate but greater than the refractive index of air. The reflection layer is formed on the second medium layer for reflecting light inside the light guide plate to emit from the light exit surface.

Description

Light guide plate structure

The present invention relates to a light guide plate structure, and more particularly to a light guide plate structure in which a refractive index of a dielectric layer formed on a light exit surface and a bottom surface of a light guide plate is between a refractive index of a light guide plate and an air refractive index.

Please refer to FIG. 1, which is a partial cross-sectional view of the keyboard 1 of the prior art. As shown in FIG. 1 , the keyboard 1 includes a bottom plate 10 , a plurality of buttons 12 , and a backlight module 14 . Each of the buttons 12 is disposed on the bottom plate 10 for the user to press, thereby performing the function that the user desires to input. The backlight module 14 is disposed under the bottom plate 10 to provide a light source for the keyboard 1 to emit light. The backlight module 14 includes a visor 140, a light guide 142, a metal plate 144, a reflective sheet 146, and a light emitting unit 148. The light shielding plate 140 is disposed under the bottom plate 10, the light guide plate 142 is disposed under the light shielding plate 140, the metal plate 144 is disposed under the light guide plate 142, and the reflective sheet 146 is disposed on the metal plate 144 and under the light guide plate 142. The light emitting unit 148 is disposed on one side of the light guide plate 142, so that the light emitted by the light emitting unit 148 can be uniformly emitted from the light guide plate 142 by utilizing a design in which the total reflection occurs in the light guide plate 142 and reflected by the reflective sheet 142, and then The button 12 is projected through the visor 140 in the direction of the bottom plate 10, thereby producing the effect of the keyboard 1 being illuminated.

In the above design, the total reflection of light is caused by the large refractive index of the light guide plate 142. The design of the refractive index (which can be regarded as 1) of the air located in the gap between the visor 140 and the light guide plate 142 is generated. However, since the surface of the light guide plate 142 is not properly protected, the light guide plate 142 is assembled to During the process of the keyboard 1, the surface of the light guide plate 142 is often attached or scratched by foreign matter (such as grease, dust, etc.), which causes the total reflection of light in the light guide plate 142 to be broken and light leakage occurs. Or the phenomenon that the light transmission distance is not long, thereby affecting the light use efficiency and the uniformity of light emission of the light guide plate 142. In addition, as can be seen from FIG. 1 , the backlight module 14 is designed such that the light guide plate 142 is disposed between the light shielding plate 140 and the reflection sheet 146 to guide the light to be uniformly emitted from the position of the corresponding button 12 , but the light guide plate 142 , The arrangement of the visor 140 and the reflective sheet 146 may occupy too much internal space of the keyboard, which is disadvantageous for the thin design of the keyboard 1.

One of the purposes of the present invention is to provide a light guide plate structure in which the refractive index of the dielectric layer formed on the light-emitting surface and the bottom surface of the light guide plate is between the refractive index of the light guide plate and the refractive index of the air to solve the above problem.

According to an embodiment, the light guide plate structure of the present invention comprises a light guide plate, a first dielectric layer, an optical microstructure, a second dielectric layer, and a reflective layer. The light guide plate has a light emitting surface and a bottom surface, and the light emitting surface and the bottom surface are opposite to each other. The first dielectric layer is formed on the light exit surface. The optical microstructure is formed on the bottom surface for emitting light from the light guide plate from the light exit surface. The second dielectric layer is formed on the optical microstructure, and the refractive index of the first dielectric layer and the second dielectric layer is smaller than the refractive index of the light guide plate Rate is greater than the refractive index of air. The reflective layer is formed on the second dielectric layer for reflecting light from the light guide plate to be emitted from the light exit surface.

In summary, the present invention utilizes a design in which the refractive index of the dielectric layer formed on the light-emitting surface and the bottom surface of the light guide plate is between the refractive index of the light guide plate and the refractive index of the air, so that the light can be surely guided. Total reflection occurs in the light plate, thereby increasing the light transmission distance of the light in the light guide plate and improving the light energy transfer effect. In addition, the optical microstructure and the reflective layer are directly formed on the light guide plate to replace the arrangement of the light shielding plate and the reflective sheet respectively disposed on the light guide plate in the prior art, and the light guide plate provided by the present invention The overall thickness of the structure can be effectively reduced to facilitate subsequent thin keyboard design. In addition, through the interlayer protection design formed by the first dielectric layer and the second dielectric layer and the reflective layer, and the second dielectric layer formed on the isolation between the light guide plate and the reflective layer, the present invention can also effectively prevent the light guide plate structure from being formed. During the assembly into the keyboard, the surface of the light guide plate is exposed or scratched by foreign matter (such as grease, dust, etc.), and the light in the light guide plate is directly absorbed by the reflective layer, thereby further enhancing the light guide plate. The light use efficiency of the structure and the uniformity of illumination.

The advantages and spirit of the present invention can be further understood by the following embodiments and the drawings.

Please refer to FIG. 2 , which is a partial cross-sectional view of a light guide plate structure 100 disposed in a keyboard 102 according to an embodiment of the present invention, as shown in FIG. 2 . The light panel structure 100 is applied to the illumination design of the keyboard 102, but is not limited to this application. In this embodiment, the light guide plate structure 100 is disposed at a position corresponding to the plurality of buttons 104 in the keyboard 102, and one of the light emitting units 106 (such as a Light Emitting Diode (LED)) in the keyboard 102 is It is disposed on one side of the light guide plate structure 100, so that the light emitted by the light emitting unit 106 can be projected through the light guide plate structure 100 toward the button 104, thereby exerting the effect that the keyboard 102 has a light emitting function.

For a detailed description of the structural design of the light guide plate structure 100, please refer to FIG. 3, which is a partially enlarged schematic view of the light guide plate structure 100 of FIG. As shown in FIG. 3, the light guide plate structure 100 includes a light guide plate 108, a first dielectric layer 110, an optical microstructure 112, a second dielectric layer 114, and a reflective layer 116, wherein the optical microstructure 112 is in the first In the figure, only the concave-convex structure is simply shown, but it is not limited thereto, and other common optical microstructure designs, such as an ink pattern layer, etc., can also be used. The light guide plate 108 has a light emitting surface 118 and a bottom surface 120. The light emitting surface 118 and the bottom surface 120 are opposite to each other. The first dielectric layer 110 is formed on the light-emitting surface 118, and the optical microstructures 112 are formed on the bottom surface 120 for scattering or diffusing light in the light guide plate 108 to be emitted from the light-emitting surface 118. The second dielectric layer 114 is formed on the light-emitting surface 118. On the optical microstructure 112, a reflective layer 116 is formed on the second dielectric layer 114 for reflecting light from the light guide plate 108 from the light exit surface 118. In this embodiment, the first dielectric layer 110 and the second dielectric layer The 114-layer is preferably formed on the light-emitting surface 118 and the optical microstructure 112 by surface coating or co-extrusion. The reflective layer 116 is preferably painted, printed, bronched, sputtered or Physical Vapor Deposition (PVD) is formed on the second dielectric layer 114, and the optical microstructure 112 is preferably Hot pressing, ink printing, or ultraviolet curing is formed on the bottom surface 120, but is not limited thereto, in other words, as long as it can be used to transfer the first dielectric layer 110, the optical microstructure 112, the second dielectric layer 114, and the reflection. The forming process of the layer 116 on the light guide plate 108 can be used for the creation of the present invention. The descriptions of the forming processes of the first dielectric layer 110, the optical microstructures 112, the second dielectric layer 114, and the reflective layer 116 are common in the prior art, and thus are not described herein.

In more detail, the present invention adopts a design in which the refractive indices of the first dielectric layer 110 and the second dielectric layer 114 are smaller than the refractive index of the light guide plate 108 and greater than the refractive index of the air, so that the light can be surely achieved in the light guide plate 108. The purpose of total reflection occurs within. For example, in this embodiment, the light guide plate 108 may be made of a polycarbonate (PC) material having a refractive index of about 1.5, and the first dielectric layer 110 and the second dielectric layer 114 may be two. It is composed of yttria material and its refractive index is approximately equal to 1.2. It should be noted that the selection of the materials of the light guide plate 108 and the first dielectric layer 110 and the second dielectric layer 114 is not limited to the above embodiment, and may be changed according to the practical application requirements of the light guide plate structure 100.

Through the above configuration, after the light is incident into the light guide plate 108, the light can travel in the light guide plate 108, and when incident on the bottom surface 120 of the light guide plate 108, the optical reflection design by the reflective layer 116 and the optical microstructure 112 The optical scattering or diffusing design projects out of the keyboard 102 from the position of the button 104 of the corresponding keyboard 102 via the light exit surface 118, thereby causing the keyboard 102 to illuminate. In the above process, since the light-emitting surface 118 of the light guide plate 108 and the bottom surface 120 are respectively formed with refractive indices greater than the refractive index of the air. The first dielectric layer 110 and the second dielectric layer 114 are smaller than the refractive index of the light guide plate 108. Therefore, the light emitted by the light emitting unit 106 can surely generate a total reflection phenomenon in the light guide plate 108, thereby increasing the light on the light guide plate. The light within 108 transmits the distance and enhances the energy transfer of the light.

In addition, in the design of directing the light from the position of the button corresponding to the keyboard through the light exit surface of the light guide plate, the present invention uses the optical microstructure 112 and the reflective layer 116 to be directly formed on the light guide plate 108. In place of the arrangement of the light shielding plate and the reflection sheet respectively disposed on the light guide plate as mentioned in the prior art, the same light guiding effect is produced. In this way, by omitting the design of the visor and the reflective sheet, the overall thickness of the light guide plate structure 100 can be effectively reduced to facilitate the subsequent thin design of the keyboard.

In addition, the interlayer protection design formed by the first dielectric layer 110 and the second dielectric layer 114 and the reflective layer 116 is formed, and the second dielectric layer 114 is formed on the isolation between the light guide plate 108 and the reflective layer 116. Preventing the surface of the light guide plate 108 from being attached or scratched by foreign matter (such as grease, dust, etc.) during the assembly of the light guide plate structure 100 into the keyboard 102, and avoiding direct light in the light guide plate 108. The reflective layer 116 absorbs, thereby further improving the light use efficiency and the uniformity of light emission of the light guide plate structure 100.

The above descriptions are only preferred embodiments of the present invention, and all changes and modifications made by the scope of the patent application of the present invention should be covered by the present invention.

1, 102‧‧‧ keyboard

10‧‧‧floor

12, 104‧‧‧ button

14‧‧‧Backlight module

100‧‧‧Light guide plate structure

106, 148‧‧‧Lighting unit

108, 142‧‧‧Light guide plate

110‧‧‧First dielectric layer

112‧‧‧Optical microstructure

114‧‧‧Second dielectric layer

116‧‧‧reflective layer

118‧‧‧Glossy

120‧‧‧ bottom

140‧‧ ‧ visor

144‧‧‧Metal plate

146‧‧‧reflector

Figure 1 is a partial cross-sectional view of a prior art keyboard.

FIG. 2 is a partial cross-sectional view showing the structure of the light guide plate according to an embodiment of the present invention.

Fig. 3 is a partially enlarged schematic view showing the structure of the light guide plate of Fig. 2.

100‧‧‧Light guide plate structure

108‧‧‧Light guide plate

110‧‧‧First dielectric layer

112‧‧‧Optical microstructure

114‧‧‧Second dielectric layer

116‧‧‧reflective layer

118‧‧‧Glossy

120‧‧‧ bottom

Claims (5)

A light guide plate structure comprising: a light guide plate having a light exit surface and a bottom surface, wherein the light exit surface and the bottom surface are opposite to each other; a first dielectric layer formed on the light exit surface; an optical microstructure Forming on the bottom surface, the light in the light guide plate is emitted from the light exit surface; a second dielectric layer is formed on the optical microstructure, and the refractive index of the first dielectric layer and the second dielectric layer is smaller than The refractive index of the light guide plate is greater than the refractive index of the air; and a reflective layer is formed on the second dielectric layer for reflecting light from the light guide plate to be emitted from the light exit surface. The light guide plate structure of claim 1, wherein the light guide plate is made of a polycarbonate material, and the first dielectric layer and the second dielectric layer are made of a cerium oxide material. The light guide plate structure of claim 1, wherein the first dielectric layer and the second dielectric layer are respectively formed on the light-emitting surface and the optical microstructure by surface coating or co-extrusion molding. on. The light guide plate structure according to claim 1, wherein the reflective layer is painted, printed, bronzing, sputtered, or physically vapor-deposited (PVD). The method is formed on the second dielectric layer. The light guide plate structure of claim 1, wherein the optical microstructure is formed on the bottom surface by hot pressing, ink printing, or ultraviolet curing.