Backlight module and display device

A backlight module includes a frame, a light guide plate, and at least one first optical film. The frame has a supporting surface. The light guide plate is disposed in the frame. The first optical film is disposed above the light guide plate. The first optical film has a first body and a first ear extending from the first body. The first ear is supported by the supporting surface. A first boundary line exists between the first body and the first ear. The first optical film includes an opening region crossing the first boundary line. The opening region has at least one opening.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This non-provisional application claims priority to and the benefit of, pursuant to 35 U.S.C. § 119(a), patent application Serial No. 201710985338.0 filed in China on Oct. 20, 2017. The disclosure of the above application is incorporated herein in its entirety by reference.

FIELD

The present invention relates to a backlight module and a display device.

BACKGROUND

Flat display devices have become a mainstream among different types of display devices. For example, all of the home televisions, monitors of personal computers and laptop computers, mobile computers, and digital cameras are products that widely use flat display devices. At present, a conventional display device mainly includes a backlight module that generates backlight and a display panel that receives the backlight and generates an image.

In a conventional backlight module, an ear protruding from an edge of an optical film is usually designed so that the optical film can be placed on a frame. However, because there is no light guide plate below the ear to provide a light source, the ear is likely to be relatively dim.

To improve this situation, conventionally, a microstructure is disposed at the bottom of the light guide plate, to change the light traveling direction to increase the luminance at the ear. However, such a method is likely to cause a problem of the ear being excessively bright.

SUMMARY

In view of this, an objective of the present invention is to provide a backlight module and a display device that are capable of resolving the foregoing problems.

To achieve the foregoing objective, a backlight module is provided according to an implementation of the present invention, including a frame, a light guide plate, and at least one first optical film. The frame has a supporting surface. The light guide plate is disposed in the frame. The at least one first optical film is disposed above the light guide plate, where the first optical film has a first body and a first ear extending from the first body, the first ear is supported by the supporting surface, a first boundary line exists between the first body and the first ear, the first optical film includes an opening region crossing the first boundary line, and the opening region has at least one opening.

In one or more implementations of the present invention, the first ear has a positioning hole, the positioning hole has a positioning hole boundary near the first boundary line, the opening region has an outer boundary on a side near the first ear, and the distance from the outer boundary to the first boundary line is less than the distance from the positioning hole boundary to the first boundary line.

In one or more implementations of the present invention, the length of the opening region in an extending direction of the first boundary line is less than or equal to 80% of the length of the first ear in the extending direction of the first boundary line.

In one or more implementations of the present invention, the backlight module further includes: at least one second optical film, where the second optical film and the first optical film are laminated, the second optical film has a second body and a second ear extending from the second body, the second ear is supported by the supporting surface, a second boundary line exists between the second body and the second ear, the second optical film does not have an opening region crossing the second boundary line, the first optical film is a diffusion film, and the second optical film includes a brightness enhancement film.

In one or more implementations of the present invention, the backlight module further includes: at least one second optical film, where the second optical film and the first optical film are laminated, the second optical film has a second body and a second ear extending from the second body, the second ear is supported by the supporting surface, a second boundary line exists between the second body and the second ear, the second optical film does not have an opening region crossing the second boundary line, the first optical film is a brightness enhancement film, and the second optical film includes a diffusion film.

In one or more implementations of the present invention, the area of the opening is equal to the area of the opening region.

In one or more implementations of the present invention, the at least one opening crosses the first boundary line.

In one or more implementations of the present invention, the number of the at least one opening is plural, and the areas of the openings gradually decrease along a direction from the first boundary line to the first ear, or the areas of the openings gradually decrease along a direction from the first boundary line to the first body.

In one or more implementations of the present invention, the shape of the at least one opening is one of or a combination of a polygon, a circle, an ellipse, a cross, or an irregular shape.

In one or more implementations of the present invention, a gap exists between the frame and the light guide plate, and the first boundary line corresponds to the gap.

A display device is provided according to another implementation of the present invention, including the backlight module described above and a display panel. The display panel is disposed on the backlight module.

In one or more implementations of the present invention, the display device further includes an outer frame. The outer frame has an accommodating space, where the backlight module and the display panel are disposed in the accommodating space, the outer frame has a side wall, and an outer surface of the side wall defines a side edge of the display device. The display panel includes a display area and a non-display area located outside the display area, and the display panel has a light-shielding layer located in the non-display area. The opening region has an inner boundary on a side near the first body, and the distance e from the inner boundary to the first boundary line meets e≤a−b−d. a is the distance from an edge of the light-shielding layer near the display area to the side edge of the display device. b is the distance from the first optical film to the light-shielding layer. d is the distance from the first boundary line to the side edge of the display device.

Based on the above, for the backlight module in the present invention, the opening is provided in the opening region of the first optical film crossing the first boundary line, and therefore, the luminance can be adjusted at the first ear of the first optical film, so that the luminance of the backlight module at an ear near the frame can be adjusted.

DETAILED DESCRIPTION

A plurality of implementations of the present invention is disclosed with reference to the drawings below, and for clear description, many practical details are described in the following descriptions. However, it should be understood that, the practical details should not be intended to limit the present invention. That is, in some implementations of the present invention, the practical details are not necessary. In addition, to simplify the drawings, some conventional and commonly-used structures and elements are simply and schematically shown in the drawings.

FIG. 1AandFIG. 1Bare respectively a partial side view of a display device10and a schematic diagram of a relationship between elements according to an implementation of the present invention.FIG. 1Cshows a scaling relationship between elements inFIG. 1B.FIG. 2is a top view of a first optical film130inFIG. 1A. First, as shown inFIG. 1AandFIG. 2, in this implementation, the display device10includes a backlight module100and a display panel200, and the display panel200is disposed on the backlight module100. The backlight module100includes a frame110, a light guide plate120, and an optical film set OFS. The frame110has a supporting surface112, and the light guide plate120is disposed in the frame110. The optical film set OFS includes at least one first optical film130, and the first optical film130is disposed above the light guide plate120. The first optical film130has a first body132and a first ear134extending from the first body132, and the first ear134is supported by the supporting surface112. A first boundary line L1exists between the first body132and the first ear134, the first optical film130includes an opening region R crossing the first boundary line L1, and the opening region R has at least one opening136. A gap G exists between the frame110and the light guide plate120, and the first boundary line L1corresponds to the gap G. In some implementations, the first optical film130may be, for example, a diffusion film or a brightness enhancement film.

In this case, the opening136is provided in the opening region R of the first optical film130crossing the first boundary line L1, so that the luminance can be adjusted at the first ear134of the first optical film130, and the luminance of the backlight module100at an ear near the frame110can be adjusted.

Specifically, because the diffusion film has a function of light scattering, the luminance decreases when the light generated by a light source (not shown) of the backlight module100penetrates through the diffusion film. In an implementation, the first optical film130is a diffusion film. When the luminance at the ear is relatively dim, the opening136is provided in the opening region R of the diffusion film crossing the first boundary line L1, so that the luminance of the backlight module100at the ear near the frame110can be increased.

It should be noted that, the optical film set OFS may include multiple diffusion films. However, not each diffusion film is necessarily provided with the opening136in the opening region R crossing the first boundary line L1. When a luminance difference that needs to be adjusted is relatively small, the opening136may be provided in only one of the multiple diffusion films. When a luminance difference that needs to be adjusted is relatively large, the opening136may be provided in multiple diffusion films. That is, the number of the diffusion films that serves as the first optical film130may be flexibly adjusted according to an actual luminance difference.

On the other hand, because a brightness enhancement film has a function of light concentration and brightness enhancement, the luminance increases when the light generated by a light source (not shown) of the backlight module100penetrates through the brightness enhancement film. The brightness enhancement film is, for example, a prism sheet, a brightness enhancement sheet, a quantum dot brightness enhancement sheet, or a reflective polarizing brightness enhancement sheet. In another implementation, the first optical film130is a brightness enhancement film. When the luminance at the ear is relatively bright, the opening136is provided in the opening region R of the brightness enhancement film crossing the first boundary line L1, so that the luminance at the ear of the backlight module100near the frame110can be decreased.

It should be noted that, the optical film set OFS may include multiple brightness enhancement films. However, the opening136does not need to be provided in the opening region R crossing the first boundary line L1for each brightness enhancement film. When a luminance difference that needs to be adjusted is relatively small, the opening136may be provided in only one of the multiple brightness enhancement films. When a luminance difference that needs to be adjusted is relatively large, the opening136may be provided in the multiple brightness enhancement films. That is, the number of the brightness enhancement films that serves as the first optical film130may be flexibly adjusted according to an actual luminance difference.

FIG. 3is a top view of a second optical film140inFIG. 1A. As shown inFIG. 1AandFIG. 3, in some implementations, the backlight module100further includes at least one second optical film140. The second optical film140and the first optical film130are laminated. The second optical film140has a second body142and a second ear144extending from the second body142. The second ear144is supported by the supporting surface112. A second boundary line L2exists between the second body142and the second ear144, and the second optical film140does not have an opening region crossing the second boundary line L2. In some implementations, the second optical film140includes, for example, a diffusion film or a brightness enhancement film.

As mentioned above, the optical film set OFS may include multiple diffusion films and multiple brightness enhancement films. When at least one of the multiple diffusion films is selected as the first optical film130that has the opening136, the remaining optical films (for example, diffusion films or brightness enhancement films) in the optical film set OFS not provided with the opening136serve as the second optical films140. When all of the diffusion films in the optical film set OFS are selected as the first optical films130that have the opening136, the remaining optical films (for example, brightness enhancement films) in the optical film set OFS not provided with the opening136serve as the second optical films140. That is, in some implementations, the first optical film130is a diffusion film, and the second optical film140includes a brightness enhancement film.

On the other hand, when at least one of the multiple brightness enhancement films is selected as the first optical film130that has the opening136, the remaining optical films (for example, diffusion films or brightness enhancement films) in the optical film set OFS not provided with the opening136serve as the second optical films140. When all of the brightness enhancement films in the optical film set OFS are selected as the first optical films130that have the opening136, the remaining optical films (for example, diffusion films) in the optical film set OFS not provided with the opening136serve as the second optical films140. That is, in some implementations, the first optical film130is a brightness enhancement film, and the second optical film140includes a diffusion film.

As can be learned from the foregoing descriptions, regardless of the relatively dim luminance or the relatively bright luminance at the ear, when the optical film set OFS has both the diffusion films and the brightness enhancement films, the opening136may be provided on at least some of the diffusion films or brightness enhancement films as required, so as to adjust the luminance.

It should be noted that,FIG. 1Ashows that the first optical film130is disposed between the second optical film140and the second optical films140′ and140″ and is merely a schematic diagram, but the present invention is not limited thereto. Persons of ordinary skill in the art can flexibly adjust a relative position of the first optical film130and the second optical film140according to an actual requirement provided that the first optical film130and the second optical film140are laminated. In addition,FIG. 1Ashows only one first optical film130and is merely a schematic diagram, but the present invention is not limited thereto. Persons of ordinary skill in the art can flexibly adjust the number of the first optical films130and the second optical films140according to an actual requirement.

Further, refer toFIG. 1A. In some implementations, the display device10further includes an outer frame300. The outer frame300has an accommodating space C, and the backlight module100and the display panel200are disposed in the accommodating space C. The outer frame300has a side wall310, and an outer surface of the side wall310defines a side edge S of the display device10. The display panel200includes a display area AA and a non-display area NA located outside the display area AA, the display panel200has a light-shielding layer210located in the non-display area NA.

Refer toFIG. 1BandFIG. 2. In this implementation, the opening region R has an inner boundary RS1on a side near the first body132. The inner boundary RS1is at a position of the opening region R, on a side near the first body132and most distant from the first boundary line L1. The distance e from the inner boundary RS1to the first boundary line L1meets e≤a−b−d. Wherein a is the distance from an edge of the light-shielding layer210near the display area AA to the side edge S of the display device10, b is the distance from the first optical film130to the light-shielding layer210, and d is the distance from the first boundary line L1to the side edge S of the display device10.

Specifically, because the opening136is provided in the opening region R, when a user views the display device10at a 45-degree viewing angle, to avoid a poor display effect when the opening136in the opening region R falls on an extending line EL of the 45-degree viewing angle, the distance e from the inner boundary RS1of the opening region R on the first body132to the first boundary line L1needs to be limited in a particular range. In other words, the inner boundary RS1cannot exceed an intersection of the extending line EL of the 45-degree viewing angle and the first optical film130.

In this way, as shown inFIG. 1BandFIG. 1C, the angle between the extending line EL of the 45-degree viewing angle and the side edge S is 45 degree, so that the distance c from an intersection point of the extending line EL of the 45-degree viewing angle and an extending line of the side edge S, to the first optical film130equals a−b. In addition, c equals e+d, and therefore, e=c−d. In this way, a relation e=a−b−d can be obtained. As can be learned, to ensure that the inner boundary RS1does not exceed the intersection of the extending line EL of the 45-degree viewing angle and the first optical film130, e needs to meet the foregoing relation e≤a−b−d, to avoid a poor display effect when the opening136in the opening region R falls on the extending line EL of the 45-degree viewing angle.

Refer toFIG. 2again. In some implementations, the first ear134has a positioning hole138, and the positioning hole138has a positioning hole boundary138S near the first boundary line L1. The opening region R has an outer boundary RS2on a side near the first ear134, distant from the first boundary line L1and near the positioning hole138. The distance D2from the outer boundary RS2to the first boundary line L1is less than the distance D1from the positioning hole boundary138S to the first boundary line L1.

Further, refer toFIG. 2. In some implementations, the length H2of the opening region R in an extending direction of the first boundary line L1is less than or equal to 80% of the length H1of the first ear134in the extending direction of the first boundary line L1, so as to keep the structure strength of the first ear134sufficient.

As shown inFIG. 2, in this implementation, the area of the opening136is equal to the area of the opening region R. By using such a design, when a luminance difference that needs to be adjusted is relatively large, the luminance can be relatively greatly adjusted.

In one or more implementations of the present invention, according to different luminance differences that need to be adjusted, design variations may be made on the opening136on the first optical film130. This is described below with reference toFIG. 4toFIG. 6.

FIG. 4is a top view of the first optical film130according to still another implementation of the present invention. As shown inFIG. 4, in this implementation, the number of openings136is plural, and the areas of the plurality of openings136gradually decrease along a direction from the first boundary line L1to the first ear134. That is, along the direction from the first boundary line L1to the first ear134, the areas of multiple openings136are designed to decrease gradually.

In addition, in some implementations, the sum of the areas of the plurality of openings136is less than or equal to 20% of the area of the opening region R. By using such a design, when a luminance difference that needs to be adjusted is relatively small, the luminance can be relatively slightly adjusted.

FIG. 5is a top view of the first optical film130according to still another implementation of the present invention. As shown inFIG. 5, in this implementation, there are at least three openings136, and the distribution number of the openings136gradually decreases along a direction from the first boundary line L1to the first ear134. That is, along the direction from the first boundary line L1to the first ear134, the areas of multiple openings136are designed to decrease gradually.

It can be learned fromFIG. 4andFIG. 5that, in some implementations, the opening region R has at least one opening136crossing the first boundary line L1, but the present invention is not limited thereto. In other implementations, the opening136in the opening region R may alternatively not cross the first boundary line L1. As shown inFIG. 6, multiple openings136are provided adjacent to the first boundary line L1, and along the direction from the first boundary line L1to the first ear134, the areas of multiple openings136are designed to decrease gradually. In addition, along a direction from the first boundary line L1to the first body132, the areas of the multiple openings136are also designed to decrease gradually. That is, a smaller distance from the first boundary line L1indicates a larger total area of the openings, and a larger distance from the first boundary line L1indicates a smaller total area of the openings.

FIG. 7AtoFIG. 7Jare schematic diagrams of the shape of the opening136according to different implementations of the present invention. In some implementations, the shape of the opening136may be one of or a combination of a polygon, a circle, an ellipse, a cross, or an irregular shape. As shown inFIG. 7A, the shape of the opening136may be, for example, a triangle. As shown inFIG. 7B, the shape of the opening136may be, for example, a rectangle. As shown inFIG. 7C, the shape of the opening136may be, for example, a square. As shown inFIG. 7D, the shape of the opening136may be, for example, a trapezium. As shown inFIG. 7E, the shape of the opening136may be, for example, a rhombus. As shown inFIG. 7F, the shape of the opening136may be, for example, a hexagon. As shown inFIG. 7G, the shape of the opening136may be, for example, a circle. As shown inFIG. 7H, the shape of the opening136may be, for example, an ellipse. As shown inFIG. 7I, the shape of the opening136may be, for example, a cross. As shown inFIG. 7J, the shape of the opening136may be, for example, a star.

Refer toFIG. 1Aagain. In some implementations, the backlight module100further includes a tape150. The tape150is used for fixing the ear of the optical film set OFS. The tape150may be, for example, a black tape or a white tape. In the present invention, a fixing manner of the ear of the optical film set OFS is not limited. In other implementations, a groove used for accommodating the ear of the optical film set OFS may further be provided at a position of the frame110corresponding to the ear, so that the ear of the optical film set OFS can be fixed in the frame110, to improve the stability of the entire structure of the backlight module100.

Based on the foregoing detailed descriptions of the specific implementations of the present invention, it can be clearly learned that, for the backlight module in the present invention, the opening is provided in the opening region of the first optical film crossing the first boundary line, and therefore, the luminance can be adjusted at the first ear of the first optical film, so that the luminance of the ear of the backlight module near the frame can be adjusted.

In conclusion, although the present disclosure is disclosed above with the embodiments, the embodiments are not intended to limit the present disclosure. A person of ordinary skill in the art to which the present disclosure belongs may make various modifications and polishing without departing from the spirit and scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.