TWI747573B - Backlight module and manufacturing method of light guiding film - Google Patents

Abstract

A backlight module includes a light guiding film, an optical structural layer and a plurality of light sources. The light guiding film has a light emitting surface, a first side and a second side. The first side and the second side are opposite to each other. The light emitting surface is connected between the first side and the second side. The first side of the light guiding film has a degree of surface roughness which ranges between about SA 0.06 and about SA 0.075. The optical structural layer is disposed on the light emitting surface. The light sources are located at the first side of the light guiding film. The light sources are configured to emit light towards the second side through the first side of the light guiding film. The light entering into the light guiding film emits towards the optical structural layer through the light emitting surface.

Description

Backlight module and manufacturing method of light guide film

The invention relates to a backlight module and a method for manufacturing a light guide film used in the backlight module.

With the continuous improvement of people's living standards, the application of electronic products has become an indispensable part of life. Among them, electronic products with display functions are becoming more and more popular. In contrast, with the rapid development of technology, people have higher and higher requirements and expectations for electronic products.

Therefore, for manufacturers, in addition to reducing the production cost of electronic products, how to improve the quality of electronic products at the same time is undoubtedly an important development direction.

One of the objectives of the present invention is to provide a backlight module, which can make the brightness of the edge display area more uniform, thereby improving the quality of the brightness provided by the backlight module.

According to an embodiment of the present invention, a backlight module includes a light guide film, an optical structure layer, and a plurality of light-emitting sources. The light guide film has a light exit surface, a first side, and a second side. The first side and the second side of the light guide film are opposite to each other. The light exit surface of the light guide film is connected between the first side and the second side. The first side has a surface roughness, and the range of the surface roughness is between about SA 0.06 and about SA 0.075. The optical structure layer is arranged on the light exit surface of the light guide film. The light source is located on the first side of the light guide film, and is configured to emit light toward the second side through the first side of the light guide film, and the light entering the light guide film is emitted to the optical structure layer through the light exit surface.

In one or more embodiments of the present invention, the aforementioned light-emitting source is a light-emitting diode.

In one or more embodiments of the present invention, the above-mentioned light guide film has a plurality of microstructures, the microstructures are formed on the first side, and the microstructures define the surface roughness.

In one or more embodiments of the present invention, the aforementioned microstructures are at least partially protruding structures.

In one or more embodiments of the present invention, the aforementioned microstructures are at least partially recessed structures.

In one or more embodiments of the present invention, the above-mentioned light guide film has two opposite long sides and two opposite short sides, and the long side and the short side are connected to each other to define the light exit surface of the light guide film, One side and the second side are respectively connected to the corresponding long sides.

In one or more embodiments of the present invention, the above-mentioned light guide film has two opposite long sides and two opposite short sides, and the long side and the short side are connected to each other to define the light exit surface of the light guide film, One side and the second side are respectively connected to the corresponding short sides.

One of the objectives of the present invention is to manufacture a light guide film, which can make the brightness of the edge display area of the backlight module more uniform, thereby improving the quality of the brightness provided by the backlight module.

According to an embodiment of the present invention, a method for manufacturing a light guide film includes: (1) providing a light guide film, the light guide film has a light exit surface, a first side and a second side, the first side and the second side of the light guide film The sides are opposite to each other, the light-emitting surface of the light guide film is connected between the first side and the second side, and the first side of the light guide film is configured to allow light to pass through and enter the light guide film; and (2) a pair of light guide films The first side of the light guide film is cut and polished, so that the first side of the light guide film has a surface roughness, and the range of the surface roughness is between about SA 0.06 and about SA 0.075.

In one or more embodiments of the present invention, the step of cutting and polishing the first side of the light guide film includes: forming a plurality of microstructures on the first side of the light guide film, and the microstructures define the guide The surface roughness of the first side of the light film.

In one or more embodiments of the present invention, the aforementioned microstructures are at least partially protruding structures.

In one or more embodiments of the present invention, the aforementioned microstructures are at least partially recessed structures.

In one or more embodiments of the present invention, the above-mentioned light guide film has two opposite long sides and two opposite short sides, and the long side and the short side are connected to each other to define the light exit surface of the light guide film, One side and the second side are respectively connected to the corresponding long sides.

In one or more embodiments of the present invention, the above-mentioned light guide film has two opposite long sides and two opposite short sides, and the long side and the short side are connected to each other to define the light exit surface of the light guide film, One side and the second side are respectively connected to the corresponding short sides.

The above-mentioned embodiments of the present invention have at least the following advantages:

(1) The first side of the light guide film has surface roughness, and the range of the surface roughness is between about SA 0.06 and about SA 0.075. Therefore, when the light emitted from the light source passes through the first side of the light guide film , The light will be more refracted, and the light entering the light guide film can also improve the uniformity. In this way, the brightness provided by the light in the edge display area can be more uniform, that is, the quality of the brightness provided by the backlight module is also improved.

(2) According to the actual situation, the user can choose to cut and polish the side of the light guide film connecting the long side, so that the side connecting the long side reaches the surface between about SA 0.06 and about SA 0.075 Roughness, or, the user can also choose to cut and polish the side of the light guide film connecting the short sides, so that the side connecting the short sides reaches a surface roughness between about SA 0.06 and about SA 0.075 Spend. Therefore, the method of processing the light guide film by the manufacturing method has considerable flexibility.

Hereinafter, a plurality of embodiments of the present invention will be disclosed in drawings. For clear description, many practical details will be described in the following description. However, it should be understood that these practical details should not be used to limit the present invention. That is to say, in some embodiments of the present invention, these practical details are unnecessary. In addition, in order to simplify the drawings, some conventionally used structures and elements will be drawn in a simple schematic manner in the drawings, and in all the drawings, the same reference numerals will be used to represent the same or similar elements. . And if it is possible in implementation, the features of different embodiments can be applied interactively.

Unless otherwise defined, all words (including technical and scientific terms) used in this article have their usual meanings, and their meanings can be understood by those familiar with the field. Furthermore, the definitions of the above-mentioned words in commonly used dictionaries should be interpreted as meaning consistent with the relevant fields of the present invention in the content of this specification. Unless specifically defined, these terms will not be interpreted as idealized or overly formal meanings.

Please refer to Figures 1-2. FIG. 1 is a schematic cross-sectional view of a backlight module 100 according to an embodiment of the present invention. Figure 2 is a schematic cross-sectional view along the line A-A in Figure 1. In this embodiment, as shown in FIGS. 1 to 2, the backlight module 100 includes a light guide film 110, an optical structure layer 120 and a plurality of light emitting sources 130. The light guide film 110 has a light exit surface 113, a first side 111, and a second side 112. The first side 111 and the second side 112 of the light guide film 110 are opposite to each other, and the light exit surface 113 of the light guide film 110 is connected to the first side 111 and the second side 112. The optical structure layer 120 is disposed on the light exit surface 113 of the light guide film 110. The light source 130 is located on the first side 111 of the light guide film 110 and is configured to emit light toward the second side 112 through the first side 111 of the light guide film 110, that is, the light source 130 is configured to pass through the light guide film 110. The first side 111 emits light into the light guide film 110, and when the light enters the light guide film 110, the light at least partly leaves the light guide film 110 through the light exit surface 113 of the light guide film 110 and is directed toward the optical structure layer 120, so that The light guide film 110 can provide brightness to the optical structure layer 120. In practical applications, the light source 130 may be light emitting diodes (LED), but the invention is not limited thereto.

Please refer to Figure 3. FIG. 3 is a schematic side view showing the application of the backlight module 100 of FIG. 1. In practical applications, as shown in FIG. 3, the backlight module 100 has an effective display area EA. Specifically, the effective display area EA is located on the brightness display surface of the optical structure layer 120 away from the light guide film 110. More specifically, there is a certain distance X between the effective display area EA and the first side 111 in the arrangement direction of the first side 111 and the second side 112.

Furthermore, as shown in FIG. 3, the effective display area EA of the backlight module 100 is equally divided into 16 equal parts, and the one closest to the light source 130 is named the edge display area EE for explanation. It is worth noting that in this embodiment, the first side 111 of the light guide film 110 has a surface roughness, and the surface roughness ranges between about SA 0.06 and about SA 0.075. Therefore, when the light emitting source 130 emits When the light passing through the first side 111 of the light guide film 110, the light will be more refracted, and the light entering the light guide film 110 can also improve the uniformity. In this way, the brightness provided by the light in the edge display area EE can be more uniform, that is, the quality of the brightness provided by the backlight module 100 can also be improved. For example, the difference between the brightest brightness and the darkest brightness of the edge display area EE may be less than 18.9.

In practical applications, for example, the surface roughness of the first side 111 of the light guide film 110 may be SA 0.060, SA 0.061, SA 0.062, SA 0.063, SA 0.064, SA 0.065, SA 0.066, SA 0.067, SA 0.068, SA 0.069, SA 0.070, SA 0.071, SA 0.072, SA 0.073, SA 0.074, or SA 0.075, etc., but the present invention is not limited thereto.

其中，Sa是基於區域形貌的粗糙度評定參數，Z為物體表面區域輪廓上點到基準平面的距離，M、N分別為評定區域中相互垂直兩個方向上的採樣點數。 To further explain, the above-mentioned surface roughness represents the arithmetic mean deviation of the topography of the region, and is used to characterize the roughness of the two-dimensional contour of the surface of the object, and the calculation formula of the surface roughness is as follows:

Among them, Sa is the roughness evaluation parameter based on the topography of the area, Z is the distance from the point on the surface area of the object to the reference plane, and M and N are the number of sampling points in the evaluation area in two directions perpendicular to each other.

Please refer to Figure 4. FIG. 4 is a partial enlarged schematic diagram showing the area B of FIG. 2, in which the microstructure 114 is a protruding structure 114a. In this embodiment, the light guide film 110 has a plurality of microstructures 114, the microstructures 114 are formed on the first side 111, and the size of the microstructures 114 is in micrometers to define the above-mentioned surface roughness. For example, as shown in FIG. 4, the microstructure 114 is at least partially a protruding structure 114a for refracting the light emitted from the light-emitting source 130 and passing through the first side 111, but the present invention is not limited to this.

Please refer to Figure 5. FIG. 5 is a partial enlarged schematic diagram showing the area B of FIG. 2, in which the microstructure 114 is a recessed structure 114b. In this embodiment, as shown in FIG. 5, the microstructure 114 of the light guide film 110 may be at least partially recessed structure 114b according to actual conditions, so as to refract the light emitted from the light-emitting source 130 and passing through the first side 111 , But the present invention is not limited to this.

Please refer to Figure 6. FIG. 6 is a partial enlarged schematic diagram showing the area B of FIG. 2, in which part of the microstructure 114 is a protruding structure 114a, and part of the microstructure 114 is a recessed structure 114b. According to the actual situation, as shown in Fig. 6, part of the microstructure 114 may be a protruding structure 114a, and part of the microstructure 114 may be a recessed structure 114b, so as to prevent the light emitting source 130 from passing through the first side 111. The light is refracted, but the present invention is not limited to this.

Please refer to Figure 7. FIG. 7 is a flowchart showing a manufacturing method 500 of the light guide film 110 according to an embodiment of the present invention. In this embodiment, as shown in Fig. 7, the manufacturing method 500 includes the following steps (it should be understood that the steps mentioned in some embodiments can be adjusted according to actual needs, unless the order is specifically stated. The sequence can be executed simultaneously or partly at the same time):

(1) Provide a light guide film 110. As described above, the light guide film 110 has a light exit surface 113, a first side 111 and a second side 112, and the first side 111 and the second side 112 of the light guide film 110 are opposite to each other, and The light exit surface 113 of the light guide film 110 is connected between the first side 111 and the second side 112, and the first side 111 of the light guide film 110 is configured to allow light to pass through and enter the light guide film 110 (step 510).

(2) The first side 111 of the light guide film 110 is cut and polished to make the first side 111 of the light guide film 110 have surface roughness. As described above, the range of the surface roughness is about SA 0.06 and Between about SA 0.075 (step 520).

Please refer to Figure 8. FIG. 8 is a top view showing the processing process of the light guide film 110 of FIG. 1. In practical applications, the user can, for example, use the polishing machine 300 to cut and polish the light guide film 110. Generally speaking, as shown in FIG. 8, the polishing machine 300 includes a working platform 310, a stop 320, a polishing head 330 and a sliding rail 340. The working platform 310 is used to support the light guide film 110, and the stop 320 is located on the working platform 310 and used to fix the position of the light guide film 110 relative to the working platform 310. The working platform 310 and the stopper 320 can move on the sliding rail 340 along the machining direction DW. Correspondingly, the polishing head 330 is stationary relative to the sliding rail 340.

Specifically, as shown in Figure 8, during the processing of the light guide film 110, the light guide film 110 can be set on the work platform 310 of the polishing machine 300, and the light guide film can be moved by the stopper 320 of the polishing machine 300 The opposite sides of the 110 are fixed along the processing direction DW. The user can abut the polishing head 330 of the polishing machine 300 against the side of the light guide film 110 parallel to the processing direction DW, and make the working platform 310 parallel to the processing direction DW. The sliding rail 340 slides relative to the polishing tool head 330 to allow the polishing tool head 330 to move relative to one side of the light guide film 110, thereby performing cutting and polishing processing on one side of the light guide film 110. In practical applications, according to the characteristics of the different surface roughness of the first side 111 of the light guide film 110, for example, to make the first side 111 of the light guide film 110 reach SA 0.060, SA 0.061, SA 0.062, SA 0.063, A specific surface roughness among SA 0.064, SA 0.065, SA 0.066, SA 0.067, SA 0.068, SA 0.069, SA 0.070, SA 0.071, SA 0.072, SA 0.073, SA 0.074 or SA 0.075, the user can choose the appropriate Polishing head 330. When one side of the light guide film 110 (for example, the first side 111) is processed, the user can sequentially rotate the placement direction of the light guide film 110 relative to the work platform 310 of the polishing machine 300 by 90 degrees and adjust the polishing head 330 The remaining three sides of the light guide film 110 are cut and polished one by one according to the above operation process to remove the burrs or edge chips on the remaining three sides of the light guide film 110.

Furthermore, the step of cutting and polishing the first side 111 of the light guide film 110 (that is, step 520) further includes: forming a plurality of microstructures 114 on the first side 111 of the light guide film 110 (step 521) . More specifically, the size of the micro structure 114 is in micrometers, and defines the surface roughness of the first side 111. As mentioned above, the microstructure 114 can be at least part of the protruding structure 114a (as shown in Figure 4), or at least part of the recessed structure 114b (as shown in Figure 5), or, according to actual conditions, part of the microstructure The structure 114 can be a protruding structure 114a, and a part of the microstructure 114 can be a recessed structure 114b (as shown in Figure 6) to better refract the light passing through the first side 111, but the present invention does not Not limited to this.

In addition, please go back to Figure 2. In this embodiment, the processed light guide film 110 has two opposite long sides 115 and two opposite short sides 116. The long sides 115 and the short sides 116 are connected to each other to define the light exit surface 113 of the light guide film 110. In other words, the light guide film 110 is substantially rectangular. In this embodiment, the first side 111 and the second side 112 of the light guide film 110 are respectively connected to the corresponding long sides 115. In other words, the first side 111 with a surface roughness between about SA 0.06 and about SA 0.075 is connected to the long side 115, and the light-emitting source 130 is also located on the long side 115 of the light guide film 110, that is, the light-emitting source 130 is in position It corresponds to the long side 115 of the light guide film 110, but the invention is not limited to this.

Please refer to Figure 9. FIG. 9 is a top view of the light guide film 110 and the light source 130 according to another embodiment of the present invention. In practical applications, as shown in FIG. 9, the light guide film 110 is substantially rectangular, and the first side 111 and the second side 112 of the light guide film 110 are respectively connected to the corresponding short sides 116. In other words, according to actual conditions, the first side 111 with a surface roughness between about SA 0.06 and about SA 0.075 is connected to the short side 116, and the light-emitting source 130 is also located on the short side 116 of the light guide film 110, that is, the light-emitting source 130 corresponds to the short side 116 of the light guide film 110 in position, but the present invention is not limited to this. In this way, according to the actual situation, the user can choose to cut and polish the side of the light guide film 110 connecting the long side 115, so that the side connecting the long side 115 reaches a range of about SA 0.06 and about SA 0.075. Alternatively, the user can also choose to cut and polish the side of the light guide film 110 connecting the short side 116, so that the side connecting the short side 116 reaches a range of about SA 0.06 and about Surface roughness between SA 0.075. Therefore, the method of processing the light guide film 110 by the manufacturing method 500 has considerable flexibility.

In summary, the technical solutions disclosed in the foregoing embodiments of the present invention have at least the following advantages:

(1) The first side of the light guide film has surface roughness, and the range of the surface roughness is between about SA 0.06 and about SA 0.075. Therefore, when the light emitted from the light source passes through the first side of the light guide film , The light will be more refracted, and the light entering the light guide film can also improve the uniformity. In this way, the brightness provided by the light in the edge display area can be more uniform, that is, the quality of the brightness provided by the backlight module is also improved.

(2) According to the actual situation, the user can choose to cut and polish the side of the light guide film connecting the long side, so that the side connecting the long side reaches the surface between about SA 0.06 and about SA 0.075 Roughness, or, the user can also choose to cut and polish the side of the light guide film connecting the short sides, so that the side connecting the short sides reaches a surface roughness between about SA 0.06 and about SA 0.075 Spend. Therefore, the method of processing the light guide film by the manufacturing method has considerable flexibility.

100: Backlight module

110: light guide film

111: first side

112: second side

113: Glossy surface

114: Microstructure

114a: protruding structure

114b: Recessed structure

115: long side

116: short side

120: Optical structure layer

130: luminous source

300: Polishing machine

310: work platform

320: stop

330: Polishing head

340: Slide

500: manufacturing method

510~520,521: steps

A-A: Line segment

B: range

DW: Processing direction

EA: effective display area

EE: Edge display area

X: distance

FIG. 1 is a schematic cross-sectional view of a backlight module according to an embodiment of the present invention. Figure 2 is a schematic cross-sectional view along the line A-A in Figure 1. FIG. 3 is a schematic side view showing the application of the backlight module of FIG. 1. FIG. Fig. 4 is a partial enlarged schematic diagram showing the area B of Fig. 2, in which the microstructures are protruding structures. FIG. 5 is a partial enlarged schematic diagram showing the area B of FIG. 2, in which the microstructure is a recessed structure. FIG. 6 is a partial enlarged schematic diagram showing the area B of FIG. 2, in which some of the microstructures are convex structures, and some of the microstructures are concave structures. FIG. 7 is a flowchart showing a method of manufacturing a light guide film according to an embodiment of the present invention. FIG. 8 is a top view showing the processing process of the light guide film of FIG. 1. FIG. FIG. 9 is a top view of a light guide film and a light-emitting source according to another embodiment of the present invention.

Domestic deposit information (please note in the order of deposit institution, date and number) none Foreign hosting information (please note in the order of hosting country, institution, date, and number) none

110: light guide film

111: first side

113: Glossy surface

114: Microstructure

114a: protruding structure

130: luminous source

B: range

Claims (13)

A backlight module includes: a light guide film having a light emitting surface, a first side, and a second side opposite to the first side, the light emitting surface is connected between the first side and the second side , The first side has a surface roughness, the range of the surface roughness is between about SA 0.06 and about SA 0.075; an optical structure layer disposed on the light emitting surface; and a plurality of light emitting sources located on the first side, And configured to emit light toward the second side through the first side with the surface roughness, and the light entering the light guide film is emitted toward the optical structure layer through the light exit surface. The backlight module according to claim 1, wherein the light-emitting sources are light-emitting diodes. The backlight module of claim 1, wherein the light guide film has a plurality of microstructures formed on the first side, and the microstructures define the surface roughness. The backlight module according to claim 3, wherein the microstructures are at least partially protruding structures. The backlight module according to claim 3, wherein the microstructures are at least partially recessed structures. The backlight module according to claim 1, wherein the light guide film has two opposite long sides and two opposite short sides, and the long sides and the short sides are connected to each other to define the light emitting surface, and the first side The corresponding long sides are respectively connected with the second side. The backlight module according to claim 1, wherein the light guide film has two opposite long sides and two opposite short sides, and the long sides and the short sides are connected to each other to define the light emitting surface, and the first side The corresponding short sides are respectively connected with the second side. A method for manufacturing a light guide film includes: providing a light guide film having a light exit surface, a first side, and a second side opposite to the first side, and the light exit surface is connected to the first side. Side and the second side; and the first side is cut and polished, so that the first side has a surface roughness, and allows light to pass through the first side with the surface roughness to emit Into the light guide film, the surface roughness ranges between about SA 0.06 and about SA 0.075. The method according to claim 8, wherein cutting and polishing the first side includes: forming a plurality of microstructures on the first side, and the microstructures define the surface roughness. The method according to claim 9, wherein the microstructures are at least partially protruding structures. The method according to claim 9, wherein the microstructures are at least partially recessed structures. The method according to claim 8, wherein the light guide film has two opposite long sides and two opposite short sides, the long sides and the short sides are connected to each other to define the light-emitting surface, and the first side and the The second sides are respectively connected to the corresponding long sides. The method according to claim 8, wherein the light guide film has two opposite long sides and two opposite short sides, the long sides and the short sides are connected to each other to define the light-emitting surface, and the first side and the The second sides are respectively connected to the corresponding short sides.

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