TWI554726B - Light guide plate and manufacturing method thereof - Google Patents

Description

Light guide plate and method of manufacturing same

The present invention relates to a light guide plate and a method of fabricating the same, and more particularly to a light guide plate for a backlight module and a method of fabricating the same.

Since the liquid crystal of the liquid crystal display panel itself does not have the illuminating property, in order to achieve a sufficient brightness display effect, the liquid crystal display panel needs to be provided with an auxiliary light source, that is, a so-called backlight module. The function of the backlight module is to supply a surface light source with sufficient brightness and uniform distribution to the liquid crystal display panel. At present, the backlight module has two types: a direct type and a side light type. Since the edge type backlight module is easier to realize a thin design, it is widely used in small and medium-sized electronic products.

A conventional edge-lit backlight module includes a light source and a light guide plate. The light guide plate includes a light incident surface, a light emitting surface connected to the light incident surface, and a reflective surface opposite to the light emitting surface. The light incident surface is a side surface of the light guide plate, and the light source is disposed adjacent to the light incident surface. a plurality of dots are disposed on the reflective surface, and the light emitted by the light source enters the light guide plate through the light incident surface of the side surface and is reflected upward through the reflective surface of the bottom portion, and is emitted from the light exit surface to provide a surface light source. The upper LCD panel.

As described above, the light guide plate utilizes total reflection to trace light to various positions in the light guide plate to achieve the effect of transmitting the light. However, the light incident surface is usually A smooth transparent mirror has a high light transmittance. Therefore, if the mirror surface is processed to produce a slight tilt angle, after the external parallel light enters the light guide plate vertically from the mirror surface, most of the light can be used after entering the light. The printing dot of the reflecting surface reflects the light supply upward, but it is easy to generate a dark band region with insufficient light at some edges of the light guiding plate, thereby affecting the light-emitting quality of the light guiding plate.

Therefore, it is necessary to provide a light guide plate and a method of manufacturing the same to solve the problems of the above conventional techniques.

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a light guide plate that is formed into an optical milling surface to avoid dark band regions as is known in the edge of the entrance surface.

Another object of the present invention is to provide a method for manufacturing a light guide plate, which performs milling on a light incident surface to improve the light guide plate by forming a milling line with an angle of less than 90 degrees between the light exit surface. The quality of light.

In order to achieve the above objective, the present invention provides a light guide plate comprising a light emitting surface, a reflecting surface, a plurality of mesh points, and at least one light-input milling surface, wherein the reflecting surface is opposite to the light emitting surface; the dots are formed in the The surface of the light-cut surface is rough, and the surface of the light-cut surface has a plurality of milling lines, and each of the milling lines and the light-emitting surface has an angle of less than 90 degrees.

In an embodiment of the invention, the light transmission milling surface has a transmittance of 60% to 90%.

In an embodiment of the invention, the light-transmitting and milling surface has a transmittance of 60%, and a radius of each of the dots is 0.15 mm, and the dots adjacent to the light-cut surface have 0.14/square. The distribution density of the metric.

In an embodiment of the invention, the light-transmitting and milling surface has a transmittance of 90%, and a radius of each of the dots is 0.2 mm, and the dots adjacent to the light-cut surface have 0.12/square. The distribution density of the metric.

In an embodiment of the invention, the distribution densities of the dots adjacent to the optical milling face are smaller than the distribution densities of the mesh points away from the optical milling face.

In an embodiment of the invention, the angle between each of the milling lines and the light exiting surface is between 30 degrees and 85 degrees.

In one embodiment of the invention, the milling lines are parallel and equidistantly arranged.

In order to achieve the above object, the present invention provides a method of manufacturing a light guide plate, the method comprising: providing a substrate having at least one processing portion at a side edge; and cutting the processed portion by using a milling cutter to form at least a surface of the optical milling surface is rough, and the surface of the optical milling surface has a plurality of milling lines, and each of the milling lines and the light emitting surface has an angle of less than 90 degrees; And printing a reflective surface of the substrate to form a plurality of dots.

In one embodiment of the invention, the substrate is made of polymethyl methacrylate (PMMA).

In an embodiment of the invention, after the ink is printed, the dots are dried.

As described above, the machining portion is removed by milling cutters, so that the light-cut surface of the light guide plate is formed with a plurality of milling lines, and each of the milling lines and the light-emitting surface has an angle of less than 90 degrees. The light transmittance of the light-cut surface is reduced, and the incident light-cut surface can scatter the incident parallel light into the multi-directional soft light through the rough microstructure of the milling line, so It can be advantageously avoided that the conventional dimming surface processing of a small dip angle tends to cause a problem of a dark band region at some edges, thereby improving the light-emitting quality of the light guide plate.

100‧‧‧Light guide plate

100'‧‧‧ substrate

101‧‧‧Processing Department

2‧‧‧Glossy surface

3‧‧‧reflecting surface

4‧‧‧ outlets

5‧‧‧Into the light milling section

51‧‧‧ Milling and cutting line

A‧‧‧ angle

Fig. 1 is a perspective view of a light guide plate according to an embodiment of the present invention.

Fig. 2 is a partial view of a light guide plate according to an embodiment of the present invention.

Fig. 3 is a schematic view showing a method of manufacturing a light guide plate according to an embodiment of the present invention.

The above and other objects, features and advantages of the present invention will become more <RTIgt; Furthermore, the directional terms mentioned in the present invention, such as upper, lower, top, bottom, front, rear, left, right, inner, outer, side, surrounding, central, horizontal, horizontal, vertical, longitudinal, axial, Radial, uppermost or lowermost, etc., only refer to the direction of the additional schema. Therefore, the directional terminology used is for the purpose of illustration and understanding of the invention.

As shown in the first and second embodiments, the light guide plate 100 of the embodiment of the present invention is matched with a light source (not shown) and assembled in a backlight module (not shown). The light guide plate 100 is a rectangular transparent plate, and the light guide plate 100 has four, for example, four light-emitting surfaces 2, a reflective surface 3, a plurality of mesh points 4, and at least one light-cut milling surface 5. In the light-cut milling surface 5, the detailed structure, assembly relationship and operation principle of each component of the light guide plate 100 will be described in detail below.

Continuing with reference to Figures 1 and 2, the light guide plate 100 may be copolymerized with polymethyl methacrylate (PMMA, acrylic), polycarbonate, polystyrene, or styrene-methyl methacrylate. A material such as a material is injection molded, and the reflecting surface 3 is opposed to the light emitting surface 2.

With reference to the first and second figures, the dots 4 can be formed on the reflecting surface 3. In the embodiment, the dots 4 are irregularly distributed, and the closer the mesh point 4 is to the light-cut milling surface 5 The more the regions are arranged, the more densely the regions are arranged, and the more densely spaced from the region of the light-cut milling surface 5, that is, the distribution density of the dots 4 close to the light-cut milling surface 5 is smaller than those far from the light-cut milling surface 5. The distribution density of the dots 4. The dots 4 are printed on the reflecting surface 3 by means of reflective ink, wherein each dot 4 is substantially partially spherically convex. In addition, in other embodiments, the dots 4 may also be chemically etched or laser printed, and the manner of forming thereof is not limited by this embodiment.

Continuing with reference to Figures 1 and 2, the surfaces of the light-cut milling faces 5 are rough, and the surface of each of the light-cut milling faces 5 has a plurality of milling lines 51, and the milling lines 51 are parallel and An equidistant arrangement, wherein each of the milling line 51 and the light-emitting surface 2 has an angle a of less than 90 degrees. In the embodiment, the angle a is 60 degrees, but in other preferred embodiments, each The angle between the milling line 51 and the light exit surface 2 is between 30 degrees and 85 degrees. The position and the number of the light-cut milling surfaces 5 depend on the position and the number of the side-entry light sources (such as LED light bars), so the light guide plate 100 can have one, two, three or four light-cut milling surfaces 5 . The light guide plate 100 can form a smooth transparent mirror surface on the side where the side-in type light source is not provided.

The light transmittance of the light-cut milling surface 5 shown in Figures 1 and 2 is preferably 60% to 90%. In the embodiment, the light-transmissive cutting surface 5 preferably has a transmittance of 60%, and the radius of each of the dots is 0.15 mm, and the dots 4 adjacent to the light-cut surface 5 have 0.14/ The distribution density of square millimeters. In addition, in other embodiments, the light transmission milling surface 5 preferably has a transmittance of 90%, and each of the dots 4 has a radius of 0.2 mm, and is adjacent to the light-cut milling surface 5. Dot 4 has a distribution density of 0.12 / mm ^ 2 .

Referring to FIGS. 1 to 3, a method of manufacturing a light guide plate according to an embodiment of the present invention mainly includes the following steps: (1) providing a substrate 100' (the light guide plate 100 of FIGS. 1 and 2), the substrate 100 'having at least one processing portion 101 at the side edge; (2) milling and removing the processing portion 101 by a milling cutter (not shown) to form at least one light-cut milling surface 5 as shown in FIG. 2, wherein The surface of the light-cut surface 5 is rough, and the surface of the light-cut surface 5 has a plurality of milling lines 51, and each of the milling lines 51 and the light-emitting surface 2 has an angle of less than 90 degrees; 3) printing a reflective ink on the reflective surface 3 of the substrate 100' to form a plurality of dots 4; and (4) drying the dots 4 to form the light guide plate 100 as shown in FIG. .

As described above, the processing portion 101 is removed by milling the cutter, and the light-cut surface 5 of the light guide plate 100 is formed with a plurality of milling lines 51, and each of the milling lines 51 and the light-emitting surface 2 are interposed therebetween. The angle of less than 90 degrees reduces the light transmittance of the light-cut milling surface 5, and the incident light milling surface 5 can scatter the incident parallel light rays through the rough microstructure of the milling line 51 into a multi-directional soft light. Light, therefore, can advantageously avoid the problem that the slight inclination of the light-incident surface is easy to cause a dark band area at some edges, and the light-emitting quality of the light guide plate 100 can be improved.

The present invention has been disclosed in its preferred embodiments, and is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

100‧‧‧Light guide plate

2‧‧‧Glossy surface

3‧‧‧reflecting surface

5‧‧‧Into the light milling section

Claims (10)

a light guide plate comprising: a light emitting surface; a reflecting surface opposite to the light emitting surface; a plurality of mesh dots formed on the reflecting surface; and at least one light milling surface, the surface of the light milling surface is rough And the surface of the light-cut surface has a plurality of milling lines, and each of the milling lines and the light-emitting surface has an angle of less than 90 degrees. According to the light guide plate of the first aspect of the patent application, the light transmittance of the light-cut surface is 60% to 90%. According to the light guide plate of claim 2, wherein the light-transmissive cutting surface has a transmittance of 60%, and the radius of each of the dots is 0.15 mm, and the dots close to the light-cut surface have 0.14. Distribution density per square millimeter. According to the light guide plate of claim 2, wherein the light transmission milling surface has a transmittance of 90%, and the radius of each of the dots is 0.2 mm, and the dots close to the optical milling surface have 0.12. Distribution density per square millimeter. The light guide plate of claim 1, wherein the distribution points of the dots adjacent to the light-cut milling surface are smaller than the distribution density of the dots away from the light-cut milling surface. According to the light guide plate of claim 1, the angle between each of the milling lines and the light exiting surface is between 30 degrees and 85 degrees. A light guide plate according to item 6 of the patent application, wherein the milling lines are arranged in parallel and equidistantly. A method for manufacturing a light guide plate, comprising: providing a substrate having at least one processing portion at a side edge; and cutting the processed portion by using a milling cutter to form at least one light-cut milling surface, the light-cut milling surface The surface of the light-cut surface has a plurality of milling lines, each of which has an angle of less than 90 degrees with the light-emitting surface; and ink printing on a reflective surface of the substrate To form several outlets. A method of manufacturing a light guide plate according to the eighth aspect of the invention, wherein the substrate is made of polymethyl methacrylate. A method of manufacturing a light guide plate according to item 8 of the patent application, wherein the ink is dried after the ink is printed.