TWI410681B - Liquid crystal display and light guide plate thereof - Google Patents

Abstract

The present invention provides a liquid crystal display and a light guide plate thereof, the light guide plate having a light emitting surface and a light incident surface. On the light emitting surface, a micro structure module, comprising a plurality of taper micro structures, is disposed along the direction perpendicular to the light incident surface. The width of one end of the taper micro structure is smaller than the width of the other end of the taper micro structure. Moreover, the linking line of one ends of the taper micro structures is a curved line, while the linking line of the other ends of the taper micro structures is a straight line or a curved line.

Description

Liquid crystal display and light guide plate thereof

The present invention relates to a light guide plate, and more particularly to a light guide plate suitable for a liquid crystal display panel.

The liquid crystal display is not a display device capable of self-illuminating source, and mainly uses the light emitted by the external light source to illuminate the liquid crystal display through the display panel, so an external light source and a corresponding light guiding device, such as a backlight module, are usually required to externally The light from the light source is directed to the display panel.

At present, the Light Emitting Diode (LED) has a low operating voltage, high luminance, fast response, and long life, and is therefore widely used as a light source for a backlight module of a liquid crystal display. However, the emitted light emitted by the light-emitting diode has strong optical directivity, that is, the emitted light has a certain divergence angle, and when it is directly involved in the light guide plate of the backlight module, the light-incident side of the light guide plate is made. It is prone to optical dark areas and it is not easy to obtain better light uniformity.

The light source of the edge-lit LED backlight structure is an air layer emitted from the light-emitting diode from the outside of the light guide plate, incident on the light guide plate, and then scattered from the light-emitting surface of the light guide plate to the liquid crystal display panel. However, because the refractive index of the light guide plate is larger than the refractive index of the air layer, under the influence of the light refraction effect, after the LED light enters the light guide plate, adjacent to the light incident surface of the light guide plate, the light of the LED will be collected to The smaller angle range makes it easier for dark areas with weaker light between the two LEDs, while dark spots of light are generated on the liquid crystal display panel, while the light guide area located directly in front of the LED produces bright spots, making it adjacent to The light distribution in the portion of the light incident surface of the light guide plate is uneven, and the display area available on the liquid crystal display panel must be reduced.

Therefore, the light guide plate of the LED backlight structure of the conventional liquid crystal display still has room for improvement.

In view of this, the main object of the present invention is to provide a light guide plate disposed near the upper surface of the light guide plate near the light incident surface, and a plurality of microstructures are disposed to pass the light through the microstructure to fill the dark band between the LEDs. Considering the LED illuminating characteristics, the appropriate microstructure length is designed to achieve uniform light distribution.

The light guide plate of the present invention comprises at least a main body and a microstructure module, wherein the main body has a light emitting surface and a light incident surface connected to the light emitting surface; and the microstructure module comprises a plurality of microstructures, which are mutually Alternatingly arranged tapered microstructures disposed on the light exit surface of the light guide plate in a direction opposite to the light incident surface, each microstructure comprising a first end; and a second end opposite to the first end, second The width of the end is less than the width of the first end. Wherein the connection of the first ends of the microstructure is a curve, and the connection of the second end of the microstructure is a straight line or a curve.

The plurality of microstructures on the light guide plate of the present invention are both tapered microstructures, and can be divided into a main tapered microstructure and a secondary tapered microstructure. The main tapered microstructure and the secondary tapered microstructure are alternately arranged with each other, and the angle of the top rounded corner of the primary tapered microstructure is different from the angle of the top rounded corner of the secondary tapered microstructure. Each microstructure is a narrow cone, but its width is gradually reduced along the first end toward the second end.

Therefore, with the structure of the light guide plate of the present invention, since the connection of the microstructures near the first end of the light incident surface of the light guide plate is a periodic function curve, the light source that enters the light entering the light guide surface of the light guide plate The position of the peak of the periodic function curve is set such that the light incident on the light incident surface of the light guide plate, through the refraction and reflection of the microstructures, exhibits a uniform light distribution on the light exit surface of the light guide plate.

Another object of the present invention is to provide a liquid crystal display having the above-mentioned light guide plate, and further comprising a plurality of light sources and a liquid crystal panel. A plurality of light sources are disposed on a light incident surface corresponding to the light guide plate, and may be a plurality of light emitting diodes disposed at a peak of a periodic function curve arranged for one of the ends of the microstructures The position is such that after the light of the light sources is incident on the light incident surface of the light guide plate, a uniform light distribution is exhibited on the light exit surface through the refraction and reflection of the microstructures. The liquid crystal panel is disposed corresponding to the light emitting surface of the light guide plate, and the liquid crystal panel has a display area and a non-display area adjacent to the display area. The display area is adjacent to the boundary of the light incident surface, corresponding to the position of the microstructures on the light guide plate, so that the edge of the display area of the liquid crystal panel is just above the microstructures on the light guide plate, so that the entire display area can be The uniform light distribution transmitted to the light-emitting surface of the light guide plate is utilized.

Referring to Fig. 1, there is shown a plan view of a light guide plate according to an embodiment of the present invention. As shown in FIG. 1 , the light guide plate 10 of the present invention includes at least a main body 100 and a microstructure module 150. The main body 100 has a light-emitting surface 110 and a light-incident surface 120. The light-incident surface 120 is connected to the light-emitting surface 110. For example, The light incident surface 120 intersects the light exit surface 110 at right angles. The microstructure module 150 is composed of a plurality of microstructures 130, for example, a tapered microstructure, a semi-cylindrical structure, a semi-elliptical spherical microstructure, or a prismatic dimensional structure, etc., disposed on the light-emitting surface 110, and Adjacent to the light incident surface 120. The line 152 of the plurality of microstructures 130 near the end of the first end 132 of the light incident surface 120 is a periodic function curve, preferably a curve of a sine function or a cosine function, or an exponential type of a sine or cosine. Function curve. The plurality of microstructures 130 are in a straight line at the line 154 away from the second end 134 of the light incident surface 120. The distance D between the one end of the microstructure 130 near the light incident surface 120 and the light incident surface 120 (see FIG. 12) is generally defined as a blank area of the light guide plate, and the purpose is to make the light of the light source, for example, illuminate. The light of the diode enters the light guide plate 10 before it hits the microstructure 130, and has a large lateral width, that is, reduces the directivity of the light, so that when the light hits the microstructure 130 on the light guide plate to emit light, the light and dark bands can be reduced. The difference is that the distance is theoretically larger as possible; but it cannot enter the display area 622 of the liquid crystal panel 620 (see FIG. 12), or overlaps with the display area 622 of the liquid crystal panel 620, and needs to reserve the difference between the brightness and the darkness. The structural change space, for example: structure size, depth, and so on. Therefore, the distance D may be due to the distance between two adjacent light sources, for example, the distance between two adjacent light-emitting diodes (LED Pitch) B (see FIG. 12), or the light-incident surface 120 to the display area. The distance between 622 has a minimum (eg, greater than 0 mm) and a maximum (eg, less than or equal to 7 mm) limit, preferably between 3 mm (mm) and 4.5 mm (mm). between. In this embodiment, the distance B between the corresponding two adjacent light-emitting diodes is 8.8 mm (mm), please refer to FIG.

Please refer to Figures 2 to 4 together. Fig. 2 is a partial perspective view of a light guide plate 10 according to an embodiment of the present invention, and Figs. 3 and 4 are a side view along the direction V1 and a side view along the direction V2, respectively, in Fig. 1 . As shown in FIG. 2 and FIG. 4, the plurality of microstructures 130 disposed on the light-emitting surface 110 are tapered protrusions protruding from the light-emitting surface 110, and can be divided into a main microstructure 130a and a secondary microstructure 130b. The angle of the included angle 138a of the top end of the main microstructure 130a is different from the angle 138b of the top rounded corner of the secondary microstructure 130b. For example, the angle 138a is smaller than the angle 138b, respectively, for providing the light exit surface in front of the light source and The brightness of the light exiting surface between the light sources. The main microstructure 130a and the secondary microstructure 130b are alternately arranged side by side to complement each other to reduce the occurrence of bright and dark bands. In this embodiment, the main microstructure 130a, the secondary microstructure 130b, the main microstructure 130a, the secondary microstructure 130b, ... are alternately arranged side by side in a ratio of 1:1, but the main microstructure 130a and The secondary microstructures 130b may also be alternately arranged side by side in a 1:2 or 3:2 ratio, and the invention is not limited thereto. However, the width of each microstructure 130 decreases in a direction away from the light incident surface 120, that is, from the width W1 of the first end 132 to the width W2 of the second end 134, to gradually slow down the amount of light, and is connected to The microstructure-free block reduces the optical difference between the second end 134 and the adjacent microstructure-free block, and can further homogenize the light. In the embodiment where the microstructure 130 is a tapered protrusion, the width W2 The system is 0, so that the optical difference between the second end 134 and the adjacent microstructure-free block is minimized to achieve a better optical effect. As shown in FIG. 3, each microstructure 130 protrudes from the top end 136 of the light exiting surface 110 to a distance D1 of the microstructure 130 near the first end 132 of the light incident surface 120, and is smaller than the top end 136 to the microstructure 130 away from the light incident surface. The distance D2 of the second end 134 of the 120 is used to make the slope of the microstructure 130 corresponding to the distance D2 or the slope slower, that is, the depth of the light incident structural surface gradually becomes shallower, and gradually reduce the corresponding position at the distance D2. The amount of light. In addition, the plurality of microstructures 130 described above, as shown in FIG. 2, wherein the main microstructure 130a and the secondary microstructure 130b have a maximum lateral width W1 close to the light incident surface 120 preferably between 39.5 micrometers (μm). Between 48.5 micrometers (μm), based on forming considerations, can be used to provide higher microstructure heights. As shown in FIG. 4, the top corner fillet 138a of the main microstructure 130a has an angle ranging between 90° and 110° for providing the brightness of the light exit surface directly in front of the light source, and the radius of curvature of the top fillet 138a. The range is between 16 micrometers (μm) and 20 micrometers (μm) to mitigate the phenomenon that the light directivity may be caused by the microstructure; the distance D3 of the top corner fillet 138a of the main microstructure 130a to the light exit surface 110 The range is between 11.5 micrometers (μm) and 14.5 micrometers (μm) to provide a high microstructure height, as shown in Figure 4.

The minor microstructure 130b has a top fillet 138b having an angular range of between 126° and 155° for reinforcing the brightness of the light exiting surface between the light source and the light source, and the radius of curvature of the top fillet 138b is between 22.5 microns ( Between μm) and 27.5 micrometers (μm), to mitigate the phenomenon of excessive optical directivity caused by the microstructure; the distance from the top rounded corner 138b of the secondary microstructure 130b to the light exiting surface 110 is in the range of 5.5 μm. (μm) and 7 microns (μm) to provide a lower microstructure height.

Referring again to Figures 5 through 7. Fig. 5 is a partial perspective view of a light guide plate 20 according to an embodiment of the present invention, and Fig. 6 and Fig. 7 are side views along the direction V1 and a side view along the direction V2, respectively, as in Fig. 1. As shown in FIG. 5 and FIG. 7, the plurality of microstructures 230 disposed on the light-emitting surface 210 are tapered recesses recessed in the light-emitting surface 210, and can be divided into a main microstructure 230a and a secondary microstructure 230b. The angle 238a of the bottom end of the main microstructure 230a is different from the angle 238b of the bottom end of the secondary microstructure 230b. For example, the angle 238a is smaller than the angle 238b, respectively, for providing the front surface of the light source. The brightness of the exit surface between the light source and the secondary microstructure 230a alternates side by side with each other to complement the deficiency and reduce the generation of bright and dark bands. In this embodiment, the main microstructure 230a, the secondary microstructure 230b, the main microstructure 230a, the secondary microstructure 230b, ... are alternately arranged side by side in a ratio of 1:1, but the main microstructure 230a and The secondary microstructures 230b may also be alternately arranged side by side in a ratio of 2:1 or 3:5, and the invention is not limited thereto. However, the width of each of the microstructures 230 decreases in a direction away from the light incident surface 220, that is, from the width W3 of the first end 232 to the width W4 of the second end 234, to reduce the amount of light, and to connect without any In the embodiment of the block, in the embodiment where the microstructure 230 is a tapered groove, the width W4 is zero for better optical effects. As shown in FIG. 6, each microstructure 230 is recessed from the bottom end 236 of the light exit surface 210 to a distance D5 of the microstructure 230 near the first end 232 of the light incident surface 220, less than the bottom end 236 to the microstructure 230 away from the entrance. The distance D6 of the second end 234 of the smooth surface 220 is used to make the light incident on the structural surface gradually shallower and reduce the amount of light emitted.

In addition, the plurality of microstructures 230 are as shown in FIG. 5, wherein the main microstructure 230a and the secondary microstructure 230b have a maximum lateral width W3 close to the light incident surface 220 of 39.5 micrometers (μm) and Between 48.5 micrometers (μm) to provide deeper microstructure depth. As shown in FIG. 7, the bottom end rounded corner 238a of the main microstructure 230a has an angle ranging between 90° and 110° for providing brightness of the light exiting surface directly in front of the light source, and the bottom end is rounded 238a. The radius of curvature ranges between 16 micrometers (μm) and 20 micrometers (μm) to mitigate the phenomenon that the structure causes excessive optical directivity; the distance from the bottom end of the main microstructure 230a to the light-emitting surface 210 is D7. Between 11.5 micrometers (μm) and 14.5 micrometers (μm) to provide deeper microstructure depth. The bottom end of the secondary microstructure 230b has an angle of between 126° and 155° to provide brightness of the front surface of the light source, and the radius of curvature of the bottom end 238b ranges from 22.5 microns ( Between μm) and 27.5 micrometers (μm), to mitigate the phenomenon of excessive optical directivity caused by the microstructure; the distance from the bottom end of the secondary microstructure 230b to the light-emitting surface 210, D8, is in the range of 5.5. Between micrometers (μm) and 7 micrometers (μm) for shallower microstructure depth.

Next, with reference to FIGS. 8 and 9, a partial plan view of the light guide plate 30 and the light guide plate 40 according to different embodiments of the present invention is separately illustrated. In the embodiment shown in FIG. 8, a plurality of microstructures 330 disposed on the light-emitting surface 310 on the light guide plate 30, and a line 352 near the first end 332 of the light-incident surface 320 are a periodic function. The curve, the periodic function curve is a combination of the partial curve line segment 3521 and the straight line segment 3522, and the minor curve segment 3521 and the straight segment 3522 are alternately arranged with each other and connected by two, and the plurality of microstructures 330 are far away from the light. The line 354 of the second end 334 of the face 320 is a straight line for reducing the occurrence of uneven brightness on the left and right when the microstructure extends to the display area.

In the embodiment shown in FIG. 9, a plurality of microstructures 430 disposed on the light-emitting surface 410 on the light guide plate 40, and a line 452 near the first end 432 of the light-incident surface 420 are a periodic function. The curve, and the plurality of microstructures 430 at the second end 434 remote from the light incident surface 420 has another periodic function curve having an opposite wave phase to the periodic function curve of the line 452 of the first end 432, Therefore, it is used to reinforce the dark band between adjacent light sources, for example, a dark band formed between adjacent light-emitting diodes.

Next, referring to Fig. 10, a plan view of a light guide plate 50 according to another embodiment of the present invention is shown. In this embodiment, the light output surface of the light-emitting surface between the light sources is longer, and the light-emitting surface corresponding to the light-emitting surface between the light sources is increased to reduce the occurrence of bright and dark bands on the light-emitting surface. As shown in the figure, the light guide plate 50 of the present invention comprises at least a main body 500 and a microstructure module 550. The main body 500 has a light-emitting surface 510 and a light-incident surface 520. The light-incident surface 520 is connected to the light-emitting surface 510. The face 520 intersects the light exit face 510 at right angles. The microstructure module 550 is composed of a plurality of microstructures 530, such as a pyramidal microstructure, a semi-cylindrical dimension structure, a semi-elliptical spherical microstructure, or a prismatic dimension structure. In the present embodiment, the microstructures 530 are disposed on the light-emitting surface 510 as described above, but the width of each of the microstructures 530 decreases in a direction away from the light-incident surface 520. The plurality of microstructures 530 are in a straight line with the line 552 near the first end 532 of the light incident surface 520, and the plurality of microstructures 530 are connected to the line 554 at the end of the second end 534 of the light incident surface 520. The periodic function curve may preferably be a curve of a sine function or a cosine function, or an exponential function curve of a sine or cosine.

Referring to FIG. 11 again, it is a side view of the light guide plate 50 as shown in FIG. 10 along the direction V1. As shown in the figure, the microstructures 530 on the light guide plate 50 are all in the foregoing embodiment, except for the configuration of the plurality of microstructures 530 on the light exit surface 510. The microstructures 530 protrude from the light exit surface 510 as shown. The elongated tapered protrusion has a distance 536 from the top end 536 of the microstructure 530 to the first end 432 of the microstructure 530 near the light incident surface 520, and is smaller than the tip end 536 to the second end 534 of the microstructure 530 away from the light incident surface 520. Distance D10. Thereby, the light source incident on the light incident surface 420 of the light guide plate 40 can be made to have a uniform light distribution on the light exit surface 510 through the refraction and reflection of the plurality of microstructures 530.

Next, with reference to FIGS. 12 and 13, a partial exploded view of a liquid crystal display according to an embodiment of the present invention is shown. The liquid crystal display 600, the plurality of light sources 610, and the liquid crystal panel 620 of the present invention, and the light guide plate 10, the light guide plate 20, the light guide plate 30, the light guide plate 40 or the light guide plate 50 in any of the above embodiments. As shown in Fig. 12, the light guide plate 10 corresponding to Fig. 1 to Fig. 4 is taken as an example. The length L of the plurality of microstructures 130 on the light guide plate 10 is at most between 4.5 mm (mm) and 7 mm (mm) to adjust the brightness and darkness caused by the light source. A plurality of microstructures 130 on the light-emitting surface 110 of the light guide plate 10 have a curve connecting at least one end thereof, and at least a portion of the curve conforms to the following equation:

The plane defined by the x direction and the y direction is parallel to the light exit surface;

x: a coordinate value parallel to the extending direction of the light incident surface;

y: a coordinate value perpendicular to the extending direction of the light incident surface;

A: The amplitude of one of the curve or the complex curve is between 1.5 mm (mm) and 4.5 mm (mm) to match the light-emitting characteristics of the light source, so that the front of the light source has a short microstructure and a light output. Less; on the contrary, the amount of light emitted between the light sources will be more, in this embodiment, preferably 2 mm;

B: the distance between two adjacent light sources, for example, the distance between two adjacent light-emitting diodes (LED Pitch), which can be between 7.5 mm (mm) and 15 mm, which can be used to match The specifications of the existing products are based on the distance between two adjacent light-emitting diodes of the future light-emitting diode backlight module, preferably 7.5 mm (mm) and 10 mm (mm). Between, and when the distance between two adjacent light-emitting diodes is larger, the phenomenon that the light-emitting diodes are brighter and darker is more difficult to be uniformized;

C: an adjustment constant between 0.2 and 1.1 for appropriately adjusting the light-emitting diode illuminating characteristic and the distance between two adjacent light-emitting diodes, which is 0.4 in this embodiment. .

A plurality of light sources 610 are disposed on the light incident surface 120 corresponding to the light guide plate 10, and the light source 610 is disposed at a position of a peak 156 of a periodic function curve arranged for one end of the plurality of microstructures 130. After the light of the light source 610 is incident on the light incident surface 120 of the light guide plate 10, it can be refracted and reflected through the plurality of microstructures 130. With the configuration of the light guide plate 10 of the present invention, the light source incident on the light incident surface of the light guide plate 10 into the light surface 120 is set at the position of the peak 156 of the periodic function curve, as shown in FIG. 12, so that the incident guide is made. The light entering the light surface 120 of the light plate 10, through the refraction and reflection of the plurality of microstructures 130, can exhibit a uniform light distribution on the light exit surface 110. The liquid crystal panel 620 is disposed corresponding to the light emitting surface 110 of the light guide plate 10 , and the liquid crystal panel 620 has a display area 622 and a non-display area 621 adjacent to the display area 622 . The display area 622 is adjacent to the boundary 6221 of the light incident surface 120, corresponding to the position of the plurality of microstructures 130 on the light guide plate 10, so that the edge of the display area 622 of the liquid crystal panel 620 is located just above the microstructure 130 on the light guide plate 10, so that The entire display area 622 can utilize a uniform light distribution transmitted through the light exit surface 110 of the light guide plate 10. In addition, the light source 610 may be a plurality of light emitting diodes or other light sources having high directivity, such as an organic light emitting diode or a laser diode.

As shown in FIG. 13 , the light guide plate 50 corresponding to FIG. 10 to FIG. 11 is taken as an example. The length L of the plurality of microstructures 530 on the light guide plate 50 is at most between 4.5 mm (mm) and 7 mm (mm). A plurality of microstructures 530 on the light-emitting surface 510 of the light guide plate 50 have a curve connecting at least one end thereof, and at least a portion of the curve conforms to the foregoing equation (Formula 1). A plurality of light sources 610 are disposed on the light incident surface 520 corresponding to the light guide plate 50, and the light source 610 is disposed at a position of a peak 556 of a periodic function curve arranged for one end of the plurality of microstructures 530. After the light of the light source 610 is incident on the light incident surface 520 of the light guide plate 50, it can be refracted and reflected through the plurality of microstructures 530. With the configuration of the light guide plate 50 of the present invention, the light source 610 that is incident on the light incident surface of the light guide plate 50 into the light surface 520 is disposed at a position of the peak 556 of the periodic function curve, as shown in FIG. The light entering the light surface 520 of the light guide plate 50, through the refraction and reflection of the plurality of microstructures 530, can exhibit a uniform light distribution on the light exit surface 510. The liquid crystal panel 620 is disposed corresponding to the light-emitting surface 510 of the light guide plate 50 , and the liquid crystal panel 620 has a display area 622 and a non-display area 621 adjacent to the display area 622 . The display area 622 is adjacent to the boundary 6221 of the light incident surface 520, corresponding to the position of the plurality of microstructures 530 on the light guide plate 50, such that the edge of the display area 622 of the liquid crystal panel 620 is located just above the microstructure 530 on the light guide plate 50, so that The entire display area 622 can utilize the uniform light distribution transmitted through the light exit surface 510 of the light guide plate 50. In addition, the light source 610 described above may be a plurality of light emitting diodes or other light sources having high directivity.

Finally, please refer to Fig. 14 for the light intensity distribution measured by the light guide plate 10 having the microstructure of the different tip fillet angles as shown in Fig. 4. As shown in Fig. 14, the top end fillet 138a of the main microstructure 130a has an angle ranging between 90° and 110°, that is, when the measured value is around 100°; and the top end of the secondary microstructure 130b is rounded 138b. The angle range is between 126° and 155°, that is, when the measured value is about 140°, the optimal combination of the illuminance of the light guide plate 10 can be achieved.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and retouched without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

10. . . Light guide

100. . . main body

110. . . Glossy surface

120. . . Glossy surface

130. . . microstructure

130a. . . Main cone microstructure

130b. . . Secondary tapered microstructure

132. . . First end

134. . . Second end

136. . . top

138a. . . Top fillet

138b. . . Top fillet

150. . . Microstructure module

152. . . First end connection

154. . . Second end connection

156. . . crest

20. . . Light guide

200. . . main body

210. . . Glossy surface

220. . . Glossy surface

230. . . microstructure

230a. . . Main cone microstructure

230b. . . Secondary tapered microstructure

232. . . First end

234. . . Second end

236. . . top

238a. . . Top fillet

238b. . . Top fillet

30. . . Light guide

300. . . Light guide body

310. . . Glossy surface

320. . . Glossy surface

330. . . microstructure

332. . . First end

334. . . Second end

352. . . First end connection

3521. . . Secondary curve segment

3522. . . Straight line segment

354. . . Second end connection

40. . . Light guide

400. . . Light guide body

410. . . Glossy surface

420. . . Glossy surface

430. . . microstructure

432. . . First end

434. . . Second end

452. . . First end connection

454. . . Second end connection

50. . . Light guide

500. . . main body

510. . . Glossy surface

520. . . Glossy surface

530. . . microstructure

532. . . First end

534. . . Second end

536. . . top

550. . . Microstructure module

552. . . First end connection

554. . . Second end connection

556. . . crest

600. . . LCD Monitor

610. . . light source

620. . . LCD panel

621. . . Non-display area

622. . . Display area

6221. . . boundary

D, D1, D2, D3, D4, D5, D6, D7, D8, D9, D10. . . length

L. . . distance

V1, V2. . . direction

W1, W2, W3, W4. . . width

1 is a plan view showing a light guide plate according to Embodiment 1 of the present invention;

2 is a partial perspective view of a light guide plate according to Embodiment 1 of the present invention;

Figure 3 is a side view along the direction V1 as in Figure 1;

Figure 4 is a side view along the direction V2 as in Figure 1;

Figure 5 is a partial perspective view of a light guide plate according to Embodiment 2 of the present invention;

Figure 6 is a side view along the direction V1 as in Figure 1;

Figure 7 is a side view along the direction V2 as in Figure 1;

Figure 8 is a partial plan view showing a light guide plate according to Embodiment 3 of the present invention;

Figure 9 is a partial plan view showing a light guide plate according to Embodiment 4 of the present invention;

Figure 10 is a plan view showing a light guide plate according to Embodiment 5 of the present invention;

Figure 11 is a side view taken along the direction V1 as in Figure 10;

Figure 12 is a partial exploded view of a liquid crystal display according to an embodiment of the present invention;

Figure 13 is a partial exploded view of a liquid crystal display according to another embodiment of the present invention;

Figure 14 is a light intensity distribution measured by a light guide having microstructures having different rounded corners as shown in Fig. 4.

10. . . Light guide

100. . . main body

110. . . Glossy surface

120. . . Glossy surface

130. . . microstructure

132. . . First end

134. . . Second end

150. . . Microstructure module

152. . . First end connection

154. . . Second end connection

D. . . distance

V1, V2. . . direction

Claims (35)

A light guide plate comprising: a main body having a light emitting surface and a light incident surface connected to the light emitting surface; and a plurality of microstructures disposed on the light emitting surface in a direction facing the light incident surface, including each other Alternating a plurality of primary microstructures and a plurality of secondary microstructures, each of the microstructures having: a first end being the end of the microstructure adjacent to the light incident surface; and a second end At the first end, the end of the microstructure away from the light incident surface, the width of the second end is smaller than the width of the first end. The light guide plate of claim 1, wherein the connecting lines of the first ends are a curve, and the connecting lines of the second ends are straight lines. The light guide plate of claim 2, wherein the curve further comprises a plurality of curve line segments and a plurality of straight line segments. The light guide plate of claim 3, wherein the straight line segments and the minor curve segments are alternately arranged and connected to each other. The light guide plate of claim 2, wherein the curve is a periodic function curve. The light guide plate of claim 5, wherein the periodic function comprises any one or a combination of the following functions: a sine function, a cosine function, a sine exponential type function, and a cosine exponential type function. The light guide plate of claim 1, wherein the connecting lines of the first ends and the connecting lines of the second ends are respectively a periodic function curve having an opposite wave phase. The light guide plate of claim 7, wherein the periodic function comprises any one or a combination of the following functions: a sine function, a cosine function, a sine exponential type function, and a cosine exponential type function. The light guide plate of claim 1, wherein the connecting lines of the first ends are in a straight line, and the connecting lines of the second ends are a curve. The light guide plate of claim 9, wherein the curve is a periodic function curve. The light guide plate of claim 10, wherein the periodic function comprises any one or a combination of the following functions: a sine function, a cosine function, a sine exponential type function, and a cosine exponential type function. The light guide plate of claim 1, wherein the microstructures are a tapered protrusion protruding from the light-emitting surface, wherein a distance from a top end of each of the tapered protrusions to a side of the tapered protrusion near the light-incident surface is smaller than the distance from the top end to the tapered protrusion The distance from one end of the light incident surface, and the width of each of the tapered protrusions decreases in a direction away from the light incident surface. The light guide plate of claim 12, wherein the angle of the taper angle of the main microstructures is between 90° and 110°. The light guide plate of claim 12, wherein the distance from the top end of the main microstructures to the light exiting surface is between 11.5 microns and 14.5 microns. The light guide plate of claim 12, wherein the major microstructures have a maximum lateral width of between one of 39.5 microns and 48.5 microns adjacent to one of the light incident faces. The light guide plate of claim 12, wherein a radius of curvature of the top end of one of the main microstructures is between 16 micrometers and 20 micrometers. The light guide plate of claim 12, wherein an angle of the minor microstructures adjacent to a cone angle of the light incident surface ranges between 126° and 155°. The light guide plate of claim 12, wherein the secondary microstructures The distance from the tip to the illuminating surface ranges between 5.5 microns and 7 microns. The light guide plate of claim 12, wherein the minor microstructures have a maximum lateral width of between one of 39.5 microns and 48.5 microns adjacent to one of the light incident faces. The light guide plate of claim 12, wherein the radius of curvature of the top end of one of the secondary microstructures ranges between 22.5 microns and 27.5 microns. The light guide plate of claim 1, wherein the microstructures are recessed into the tapered grooves of the light-emitting surface, wherein one of the bottom ends of each of the tapered grooves is adjacent to the light-incident surface of the tapered groove The distance of one end is smaller than the distance from the bottom end to the one end of the tapered groove away from the light incident surface, and the width of each of the tapered grooves decreases in a direction away from the light incident surface. The light guide plate of claim 21, wherein the angle of the taper angle of the main microstructures is between 90° and 110°. The light guide plate of claim 21, wherein the distance from the bottom end of the main microstructures to the light exiting surface is between 11.5 microns and 14.5 microns. The light guide plate of claim 21, wherein a maximum lateral width of the one of the main microstructures adjacent to the light incident surface is between 39.5 microns and 48.5 microns. The light guide plate of claim 21, wherein the bottom end of one of the main microstructures has a radius of curvature ranging between 16 micrometers and 20 micrometers. The light guide plate of claim 21, wherein an angle of the minor microstructures near a taper angle of the light incident surface ranges between 126° and 155°. The light guide plate of claim 21, wherein the distance from the bottom end of the secondary microstructures to the light exiting surface ranges between 5.5 microns and 7 microns. The light guide plate of claim 21, wherein a range of the maximum lateral width of the secondary microstructures adjacent to the light incident surface is between 39.5 microns and 48.5 microns. The light guide plate of claim 21, wherein the bottom end of one of the secondary microstructures has a radius of curvature ranging between 22.5 microns and 27.5 microns. The light guide plate of claim 1, wherein the first ends and the The distance between the entrance faces is between 3 mm and 4.5 mm. A liquid crystal display, comprising: the light guide plate according to any one of claim 1 to claim 30; a plurality of light sources corresponding to the light incident surface of the light guide plate; and a liquid crystal panel corresponding to the The light exit surface of the light guide plate is disposed. The liquid crystal display of claim 31, wherein the microstructures have a length of at most between 4.5 mm and 7 mm. The liquid crystal display of claim 31, wherein the light sources are a plurality of light emitting diodes. The liquid crystal display of claim 31, wherein the liquid crystal panel comprises a display area and a non-display area adjacent to the display area. The liquid crystal display of claim 34, wherein the display area is adjacent to a boundary of the light incident surface and corresponds to a position of the microstructures on the light guide plate.