CN213715498U - Light guide plate - Google Patents

Abstract

The utility model discloses a light guide plate, it has the income light surface to and be adjacent to the light-emitting surface of going into the light surface. The light guide plate comprises a plurality of light guide units. A plurality of light guide units are disposed inside the light guide plate, each of the plurality of light guide units having a lower surface and an upper surface opposite to each other. The lower surface is located between the light emergent surface and the upper surface, and the surface area of the lower surface is larger than that of the upper surface. The utility model discloses a light guide unit sets up in the light guide plate to can borrow the effect in order to realize the guide light by the specific shape of light guide unit.

Description

Light guide plate

Technical Field

The present invention relates to an optical device, and more particularly to a light guide plate for a front light module.

Background

The backlight module includes a light source and a light guide plate, wherein dots are generally printed on the surface or bottom of the light guide plate, and light from the light source is guided by the dots with different densities and sizes. Specifically, light generated by the light source enters the light guide plate from the light incident surface of the light guide plate, and finally leaves the light guide plate from the light emitting surface of the light guide plate by the inner surface of the light guide plate and the guiding direction of the dots on the surface or the bottom surface. That is, the dots are light guiding units for guiding light, and the shape and distance between the dots determine the light guiding effect.

More specifically, the light guide plate can be printed with diffusion dots on the surface or the bottom surface to diffuse the reflected light at various angles, and the total reflection of the light is destroyed by the design of the diffusion dots with different densities and sizes. However, in the subsequent process, the light guide plate needs to be coated with a solid clear optical adhesive (OCA) or a liquid clear optical adhesive (OCR) and bonded to other components. Therefore, the diffused dots will lose the function of destroying the total reflection because of being filled up, further resulting in a dark visual effect of the display, and thus the using effect of the reader is poor.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a light guide plate solves and sets up at the light guide unit on light guide plate surface at present and receives the viscose influence, leads to the problem that optical property descends.

In order to solve the technical problem, the utility model discloses a realize like this:

in a first aspect, a light guide plate is provided, which has a light incident surface and a light emergent surface adjacent to the light incident surface. The light guide plate comprises a plurality of light guide units. A plurality of light guide units are disposed inside the light guide plate, each of the plurality of light guide units having a lower surface and an upper surface opposite to each other. The lower surface is located between the light emergent surface and the upper surface, and the surface area of the lower surface is larger than that of the upper surface.

In a second aspect, a light guide plate is provided, which has a light incident surface and a light emergent surface adjacent to the light incident surface, and the light guide plate includes a plurality of first light guide units and a plurality of second light guide units. The plurality of first light guide units are arranged inside the light guide plate, each of the plurality of first light guide units is provided with a first lower surface and a first upper surface which are opposite to each other, and the first lower surface is positioned between the light emergent surface and the first upper surface. The plurality of second light guide units are positioned in the light guide plate and are respectively arranged on each of the plurality of first light guide units, each of the plurality of second light guide units is provided with a second lower surface and a second upper surface which are opposite to each other, the second lower surface is positioned on the first upper surface, and the surface area of the first lower surface is larger than that of the second upper surface.

The embodiment of the utility model provides an in, borrow inside setting up the light guide unit at the light guide plate to avoid the light guide unit to receive the coating and influence at the surperficial viscose of light guide plate, make the not good problem of leaded light nature. Furthermore, the surface area of the lower surface of the light guide unit is larger than that of the upper surface, so that the light guide plate can effectively guide the light to the light emergent surface.

Drawings

Fig. 1 is a sectional view of a light guide plate according to a first embodiment of the present invention;

fig. 2 is a schematic view of a light guide unit according to a first embodiment of the present invention;

fig. 3 is a sectional view of a light guide plate according to a second embodiment of the present invention;

fig. 4 is a schematic view of a light guide unit according to a second embodiment of the present invention;

fig. 5 is a sectional view of a light guide plate according to a third embodiment of the present invention;

FIGS. 6-8 are schematic views of the light path of the present invention;

FIGS. 9-11 are schematic views of the light guide plate of the present invention; and

fig. 12-14 are schematic views of another process of the light guide plate of the present invention.

Description of reference numerals:

1 light guide plate

110 incident light surface

120 light exit surface

130 light reflecting surface

140 light guide unit

141 lower surface

142 upper surface

143 side surface

2A light guide plate

2B light guide plate

210 incident light surface

220 light exit surface

230 light reflecting surface

240 first light guide unit

241 first lower surface

242 first upper surface

243 first side surface

250 second light guide unit

251 second lower surface

252 second upper surface

253 second side surface

260 second light guide unit

261 second lower surface

262 second upper surface

263 second side surface

d 1-d 7 thickness

Theta 1 first angle

Theta 2 second angle

Theta 3 third angle

Theta 4 fourth angle

Detailed Description

For further understanding and appreciation of the features and effects achieved by the present invention, the following detailed description is provided only by way of example and in conjunction with the accompanying drawings, in which:

please refer to fig. 1 and fig. 2, which are a cross-sectional view of a light guide plate and a schematic diagram of a light guide unit according to a first embodiment of the present invention. As shown, the light guide plate 1 has a light incident surface 110 and a light emergent surface 120 adjacent to the light incident surface. When applied to a front light module, the light source is disposed on the light incident surface 110 side of the light guide plate 1, and is disposed on the left side of the light guide plate 1, taking fig. 1 as an example. Light generated by the light source enters the light guide plate 1 through the light incident surface 110. The light guide plate light exit surface 120 is typically designed to be close to the display. The guided light leaves the light guide plate 1 by the light exit surface 120.

In this embodiment, the light guide plate 1 may further include a light reflecting surface 130, and the light reflecting surface 130 is adjacent to the light incident surface 110 and opposite to the light emergent surface 120. The light reflecting surface 130 is used to reflect light inside the light guide plate 1, so that the light can be guided within the light guide plate 1 and exit from the light exit surface 120. In some embodiments, the reflective surface 130 may comprise a thin film with high reflectivity, for example, the thin film with high reflectivity may be composed of a metal or a nitride of a metal. The metal or metal nitride can transmit light and have high reflectivity even at an extremely thin thickness. Alternatively, the high-reflectivity film may be formed of epoxy and formed on the light reflecting surface 130 by coating.

The light guide plate 1 includes a plurality of light guide units 140. A plurality of light guide units 140 are disposed inside the light guide plate 1, and each light guide unit 140 has a lower surface 141 and an upper surface 142 opposite to each other. The lower surface 141 is close to the light exit surface 120, or between the light exit surface 120 and the upper surface 142, and the surface area of the lower surface 141 is larger than that of the upper surface 142. Therefore, in the present embodiment, by disposing the light guide unit 140 with a specific geometric shape inside the light guide plate 1, the light guide effect can be achieved, and the problem of performance reduction and even failure of the light guide unit caused by the optical adhesive on the surface or bottom surface of the light guide plate can be avoided.

In the present embodiment, the lower surface 141 and the upper surface 142 of the light guide unit 140 are parallel to the light exit surface 120, so as to improve the light guide effect. However, in some embodiments, the lower surface 141 and the upper surface 142 of the light guide unit 140 may not be parallel to the light exit surface 120.

In the present embodiment, the lower surface 141 and the upper surface 142 of the light guide unit 140 are quadrangles with four sides having the same length. Lower surface 141 has a first side length and upper surface 142 has a second side length, with the first side length being greater than the second side length. In some embodiments, the lower surface 141 and the upper surface 142 of the light guide unit 140 may also be quadrilateral with four sides having different lengths, and are configured according to practical use situations. In the present embodiment, each light guiding unit 140 further has a side surface 143, the side surface 143 is adjacent to the lower surface 141 and the upper surface 142, and the side surface 143 and the upper surface 142 form a first angle θ 1. In practical applications, when light enters the light guide plate 1 from the light incident surface 110 and contacts the side surface 143, the light is refracted, reflected, and scattered. These refractions and reflections follow the relationship between the angle of incidence and the normal. That is, the first angle θ 1 between the side surface 143 and the upper surface 142 also affects the inclination of the side surface 143, i.e., the normal direction of the side surface 143, and further affects the light guiding function. In addition, since the surface area of the lower surface 141 of the light guide unit 140 is larger than that of the upper surface 142, the first angle θ 1 between the side surface 143 and the upper surface 142 cannot be 90 degrees. More specifically, the first angle θ 1 between the side surface 143 and the upper surface 142 is greater than 90 degrees and less than 180 degrees. For example, the first angle θ 1 may be between 120 degrees and 150 degrees. When it is desired that the side surface 143 is more nearly parallel to the light incident surface 110, the first angle θ 1 may be smaller, such as 120 degrees. When the more inclination between the side surface 143 and the light incident surface 110 is required, the first angle θ 1 may be larger, such as 150 degrees. It should be noted that the range of the first angle θ 1 is only exemplary and should not be taken as a limitation of the present invention, and the above-described function can be realized as long as the first angle θ 1 is greater than 90 degrees and less than 180 degrees.

The surface of the light guide unit 140 may be coated with a reflective material. These reflective materials may be the same as the reflective materials described above for the reflective surface 130 and therefore will not be described in detail. The light path can be more accurately controlled by the additionally coated reflecting material, so that the light guide effect is better.

Please refer to fig. 3 and 4, which are a cross-sectional view of a light guide plate and a schematic view of a light guide unit according to a second embodiment of the present invention. As shown, the light guide plate 2A has a light incident surface 210 and a light emergent surface 220 adjacent to the light incident surface 210. The light guide plate 2A includes a plurality of light guide units, each of which is composed of a first light guide unit 240 and a second light guide unit 250. The first light guiding units 240 are disposed inside the light guiding plate 2A, each of the first light guiding units 240 has a first lower surface 241 and a first upper surface 242 opposite to each other, and the first lower surface 241 is located between the light emitting surface 220 and the first upper surface 242. The plurality of second light guide units 250 are located inside the light guide plate 2A and respectively disposed on each of the plurality of first light guide units 240, each of the plurality of second light guide units 250 has a second lower surface 251 and a second upper surface 252 opposite to each other, the second lower surface 251 is located on the first upper surface 242, and a surface area of the first lower surface 241 is greater than a surface area of the second upper surface 252. As described above, each of the plurality of first light guide units 240 is spatially closer to the light exit surface 220 than each of the plurality of second light guide units 250.

In this embodiment, the light guide plate 2A may be made of the same material as the light guide plate 1. Similarly, the light guide plate 2A may further include a light reflecting surface 230, and the light reflecting surface 230 is adjacent to the light incident surface 210 and opposite to the light emergent surface 220. The details thereof are not repeated.

Compared with the first embodiment, the light guide unit for guiding light in this embodiment is further divided into an upper layer and a lower layer, where the lower layer is the first light guide unit 240 and the upper layer is the second light guide unit 250. As shown in fig. 3 and 4, the first lower surface 241 of the first light guide unit 240 is a quadrangle with four sides having the same length, and has a third side. The second upper surface 252 of the second light guiding unit 250 is also a quadrilateral with four sides having the same length, and the fourth side length is smaller than the third side length. For the light guide unit of the present invention, the function of the present embodiment can be realized as long as the condition that the surface area of the first lower surface 241 is larger than the surface area of the second upper surface 252 is satisfied. In other words, the light guide units of the first and second embodiments are configured according to the feature that the surface area of the lowest surface is larger than the surface area of the highest surface, so that the light can be effectively guided to the light exit surface of the light guide plate.

In the present embodiment, the first light guiding units 240 further have first side surfaces 243, the first side surfaces 243 are adjacent to the first lower surfaces 241 and the first upper surfaces 242, the first side surfaces 243 and the first upper surfaces 242 form a second angle θ 2, each of the second light guiding units 250 further has second side surfaces 253, the second side surfaces 253 are adjacent to the second lower surfaces 251 and the second upper surfaces 252, and the second side surfaces 253 and the second upper surfaces 252 form a third angle θ 3. In the present embodiment, the second angle θ 2 is 90 degrees, that is, the first light guiding unit 240 is a rectangular parallelepiped, and the surface area of the first lower surface 241 is equal to the surface area of the first upper surface 242. In addition, the third angle θ 3 is also 90 degrees, that is, the second light guiding unit 250 is a rectangular parallelepiped, and the surface area of the second lower surface 251 is equal to the surface area of the second upper surface 252. From a cross-sectional view, the stack of the first light guiding unit 240 and the second light guiding unit 250 looks like a "convex" shape.

In the present embodiment, the stack of the first light guide unit 240 and the second light guide unit 250 is hollow. Similarly, each surface of the first light guiding unit 240 and the second light guiding unit 250 may also be coated with a reflective material, and the path of light can be more precisely controlled by the additionally coated reflective material, so that the light guiding effect is better.

Please refer to fig. 5, which is a cross-sectional view of a light guide plate according to a third embodiment of the present invention. As shown in the figure, the light guide plate 2B and the light guide plate 2A are different only in the second light guide unit, and other elements have similar or identical functions, and thus are not described again. In the present embodiment, the light guide plate 2B includes a first light guide unit 240 and a second light guide unit 260. In the first light guide unit 240, the second angle θ 2 between the first upper surface 242 and the first side surface 243 is 90 degrees, that is, the first light guide unit 240 is a rectangular parallelepiped, and the surface area of the first lower surface 241 is equal to the surface area of the first upper surface 242. However, in the second light guiding unit 260, the fourth angle θ 4 between the second upper surface 262 and the second side surface 263 is greater than 90 degrees and less than 180 degrees, that is, the surface area of the second lower surface 261 is not equal to the surface area of the second upper surface 262, so that the second light guiding unit 260 has a pyramid shape. Further, in this embodiment, compared with the first and second embodiments described above, the light guide unit for guiding light also has a feature that the surface area of the lowermost lower surface is larger than the surface area of the uppermost upper surface, and the difference is only the design on the side surface of the light guide unit. That is, in actual use, one of the light guide plate 1, the light guide plate 2A, and the light guide plate 2B may be arranged according to different situations.

Please refer to fig. 6 to 8, which are schematic views of light paths according to the present invention. The present embodiment is a simulation of a light-guiding path, which refers to the light-guiding plate 2A of the second embodiment in fig. 3. In addition, in order to make the simulation process simple and easy to understand, only one first light guide unit 240 and one second light guide unit 250 are considered. As shown in fig. 6, after the light L enters from the light entrance surface 210, the light L is reflected by the first light guide unit 240 and the second light guide unit 250 stacked inside. The reflected light L is incident toward the light reflecting surface 230 and exits the light exit surface 220 in a nearly vertical direction by reflection from the light reflecting surface 230. As shown in fig. 7, after entering from the light entrance surface 210, the light L is refracted by the first light guiding unit 240 and then directly exits from the light exit surface 220. As shown in fig. 8, after entering from the light entrance surface 210, the light L is refracted by the first light guiding unit 240, reflected by the light exit surface 220, and finally reflected by the light reflection surface 230 and exits from the light exit surface 220.

Specifically, when the light L enters the light guide plate 2A and is diffused upward, the light L is totally reflected in the light guide plate 2A and reused as long as the included angle between the light L and the light reflecting surface 230 is greater than 41.5 °. In addition, the light L is refracted by the light guide units (i.e., the first light guide unit 240 and the second light guide unit 250) and then emitted upward, which has the same effect. That is, when the refraction angle is greater than 41.5 ° for the light guide unit, or when the incidence angle is greater than 41.5 ° for the light reflection surface 230, the light L is totally reflected and emitted back to the light guide plate 2A for recycling. In addition, when the light L enters the light guide plate 2A and then scatters light downward, the light L leaves the light guide plate 2A and is projected on the reflective layer of the display, and then enters the eyes of the user upward, so that the user can see the characters or images on the display.

It should be noted that the light L does not necessarily have 100% reflection or 100% refraction when contacting various interfaces of the transparent light guide unit, that is, the three paths are part of all possible conducting paths, and will also vary according to various factors such as the size, shape, filler, surface-coated reflective layer, and the light-reflecting surface 230 of the light guide plate 2A of the first light guide unit 240 and the second light guide unit 250. Further, the relative distance between two adjacent light guide units also affects the path of light. Please refer to fig. 9 to 11, which are schematic views of the manufacturing process of the light guide plate according to the present invention. As shown in fig. 9, a base portion of the light guide plate 1 is formed by disposing a photo-curable resin and irradiating light of a specific wavelength through 3D printing. For example, the thickness d1 may be 0.25 mm. As shown in fig. 10, a groove of a specific shape is formed on the base portion of the light guide plate 1, and the thickness d2 of this groove may be 0.05 mm. As shown in fig. 11, finally, the upper cover portion of the light guide plate 1 is continuously formed over these grooves, resulting in the light guide plate 1. In addition, the thickness d3 may be 0.25 mm. The light guide plate 1 is formed by stacking the layers one by one in a 3D printing manner, so that the light guide plate 1 for the front light module can be effectively and simply obtained, and the light guide unit 140 is prevented from being arranged on the surface of the light guide plate 1 and being influenced by the adhesive.

Please refer to fig. 12 to 14, which are schematic views of another process stage of the light guide plate 2A according to the present invention. As shown in fig. 12, after the base portion of the light guide plate 2A is formed by 3D printing, a first groove of a specific shape is formed on the base portion of the light guide plate 2A. For example, the thickness d4 may be 0.25 mm. The thickness d5 of this groove may be 0.05 mm. As shown in fig. 13, a second specific-shaped groove is formed on the first specific-shaped groove of the light guide plate 2. The thickness d6 of this groove may also be 0.05mm, for example. As shown in fig. 14, the upper cover portion of the light guide plate 2 is finally formed continuously over these grooves, resulting in a light guide plate 2A. In addition, the thickness d7 may be 0.25 mm.

To sum up, the utility model provides a light guide plate and contain its display module borrows by setting up the leaded light unit inside the light guide plate to avoid the leaded light unit to receive the coating and influence at the viscose on the light guide plate surface, make the not good problem of leaded light nature. Furthermore, the surface area of the lower surface of the light guide unit is larger than that of the upper surface, so that the light guide plate can effectively guide the light to the light emergent surface.

The above-mentioned embodiments are only examples of the present invention, and are not intended to limit the scope of the present invention, and all equivalent changes and modifications of the shape, structure, characteristics and spirit described in the claims of the present invention should be included in the scope defined by the claims of the present invention.

Claims (9)

1. A light guide plate having a light incident surface and a light exiting surface adjacent to the light incident surface, the light guide plate comprising:

the light guide unit comprises a light guide plate and a plurality of light guide units, wherein the light guide units are arranged in the light guide plate, each light guide unit is provided with a lower surface and an upper surface which are opposite to each other, the lower surface is positioned between the light emergent surface and the upper surface, and the surface area of the lower surface is larger than that of the upper surface.

2. The light guide plate according to claim 1, wherein each of the light guide units further has a side surface adjacent to the lower surface and the upper surface, and the side surface forms a first angle with the upper surface.

3. The light guide plate according to claim 2, wherein the first angle is greater than 90 degrees and less than 180 degrees.

4. The light guide plate according to claim 1, further comprising a light reflecting surface adjacent to the light incident surface and opposite to the light exit surface.

5. A light guide plate having a light incident surface and a light exiting surface adjacent to the light incident surface, the light guide plate comprising:

a plurality of first light guide units arranged inside the light guide plate, each of the plurality of first light guide units having a first lower surface and a first upper surface opposite to each other, the first lower surface being located between the light exit surface and the first upper surface; and

and the second light guide units are positioned in the light guide plate and are respectively arranged on each of the first light guide units, each of the second light guide units is provided with a second lower surface and a second upper surface which are opposite to each other, the second lower surface is positioned on the first upper surface, and the surface area of the first lower surface is larger than that of the second upper surface.

6. The light guide plate according to claim 5, wherein each of the first light guiding units further has a first side surface adjacent to the first lower surface and the first upper surface at a second angle, and each of the second light guiding units further has a second side surface adjacent to the second lower surface and the second upper surface at a third angle.

7. The light guide plate according to claim 6, wherein the second angle is equal to 90 degrees and the third angle is equal to 90 degrees.

8. The light guide plate according to claim 6, wherein the second angle is equal to 90 degrees, and the third angle is greater than 90 degrees and less than 180 degrees.

9. The light guide plate according to claim 5, further comprising a light reflecting surface adjacent to the light entrance surface and opposite to the light exit surface.

Images