Patent Publication Number: US-2023133614-A1

Title: Backlight module and display apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority benefit of China application serial no. 202122625729.6 filed on Oct. 29, 2021. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification. 
     BACKGROUND 
     Technical Field 
     This disclosure relates to an optical module and an optical apparatus, and particularly relates to a backlight module and a display apparatus. 
     Description of Related Art 
     The current blue backlight module generally includes a blue light-emitting element, a quantum dot film arranged on the blue light-emitting element, and multiple prims sheets arranged on the quantum dot film. The blue light-emitting element is utilized to emit the blue band of visible light. After the conversion of the quantum dot film, part of the blue band is converted into other bands of visible light, thereby producing white light perceived by the human eye. Generally speaking, the white light field on the quantum dot film is of the Lambertian type, and it is necessary to use multiple prism sheets to converge the white light field of the Lambertian type to enhance the brightness of emergent light from the backlight module. However, there are still some white lights with large divergence angles that cannot be condensed by multiple prism sheets, and therefore the brightness of emergent light from the backlight module cannot be further enhanced. 
     The information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Further, the information disclosed in the Background section does not mean that one or more problems to be resolved by one or more embodiments of the disclosure was acknowledged by a person of ordinary skill in the art. 
     SUMMARY 
     The disclosure provides a backlight module that provides s good performance in brightness of emergent light. 
     The disclosure provides a display apparatus, which provides a good performance in brightness of emitted light. 
     Other purposes and advantages of the disclosure can be further understood from the technical features disclosed in the disclosure. 
     In order to achieve one or part or all of the above purposes or other purposes, the backlight module of an embodiment of the disclosure includes a light-emitting element, a quantum dot film, at least one optical film and a light adjusting element. The light-emitting element is adapted to emit a blue light. The quantum dot film is arranged on a transmitting path of the blue light, and adapted to convert a first portion and a second portion of the blue light into a red light and a green light, respectively. The at least one optical film is disposed on the quantum dot film. The light adjusting element is disposed between the at least one optical film and the quantum dot film. The light adjusting element has a first surface and a second surface respectively facing the quantum dot film and the at least one optical film. The first surface has multiple first optical microstructures. The multiple first optical microstructures include multiple cones protruding toward the quantum dot film. 
     In order to achieve one or part or all of the purposes or other purposes, the display apparatus of an embodiment of the disclosure includes the backlight module and a display panel disposed on the backlight module. 
     In an embodiment of the disclosure, the bottom surface of each of the multiple cones is polygonal. 
     In an embodiment of the disclosure, the bottom surface of each of the multiple cones is rounded. 
     In an embodiment of the disclosure, the multiple cones include multiple pyramid-like cones. Each of the multiple pyramid-like cones has a bottom surface, a top surface, and multiple side surfaces, and the bottom surface and the top surface are arranged opposite to each other. The vertex of each of the pyramid-like cones is located on the top surface, and multiple side surfaces are arranged between the bottom surface and the top surface. 
     In an embodiment of the disclosure, the top surface is a flat surface or a convex surface. 
     In an embodiment of the disclosure, each of the multiple pyramid-like cones further has multiple junction surfaces, and each of the multiple junction surfaces is disposed between the multiple side surfaces and between the bottom surface and the top surface. 
     In an embodiment of the disclosure, the junction surface is a flat surface or a convex surface. 
     In an embodiment of the disclosure, each of the multiple cones has a bottom surface, multiple side surfaces, and a vertex. The bottom surface and the vertex are disposed opposite to each other. The multiple side surfaces are disposed between the bottom surface and the vertex, and each of the multiple side surfaces include a first side surface and the second side surface, the first side surface and the second side surface adjacent to each other. Both sides of the first side surface connected to the vertex form a first angle, and both sides of the second side surface connected to the vertex form a second angle, and the angle of the first angle is different from the angle of the second angle. 
     In an embodiment of the disclosure, each of the multiple cones has a bottom surface, multiple side surfaces, and a vertex. The bottom surface and the vertex are disposed opposite to each other. The multiple side surfaces are disposed between the bottom surface and the vertex. Both sides of each of the multiple side surfaces connected to the vertex form an angle, and a range of the angle from 5° to 175°. 
     In an embodiment of the disclosure, the second surface of the light adjusting element has multiple second optical microstructures, and the shape of each of the multiple first optical microstructures is different from the shape of each of the multiple second optical microstructures. 
     In an embodiment of the disclosure, the multiple second optical microstructures include multiple convex lenses protruding toward the at least one optical film. 
     In an embodiment of the disclosure, the multiple vertical projections of the multiple convex lenses on the quantum dot film are multiple circles. 
     In an embodiment of the disclosure, the multiple vertical projections of the multiple convex lenses on the quantum dot film are multiple ovals. 
     In an embodiment of the disclosure, the multiple second optical microstructures include multiple columns. The multiple columns extend in a first direction. The multiple cones are arranged in an array in the first direction and the second direction, and the first direction is staggered with the second direction. 
     In an embodiment of the disclosure, the cross section of each of the multiple columns perpendicular to the first direction is a triangle. 
     In an embodiment of the disclosure, the cross section of each of the multiple columns perpendicular to the first direction is a part of a circle. 
     In an embodiment of the disclosure, the at least one optical film includes a first prism sheet, a second prism sheet, and a diffuser. The light adjusting element is disposed between the first prism sheet and the quantum dot film, and the first prism sheet has multiple first prism columns extending in the third direction. The first prism sheet is arranged between the second prism sheet and the light adjusting element. The second prism sheet has multiple second prism columns extending in the fourth direction, and the third direction is staggered with the fourth direction. The second prism sheet is disposed between the diffuser and the first prism sheet. 
     Based on the above, part of the white light with a large divergence angle from the quantum dot film can be guided to the positive direction through the multiple cones of the first surface of the light adjusting element. In this way, the white light from the quantum dot film can be fully utilized to achieve the effect of improving the brightness of emergent light from the backlight module. 
     In order to make the above-mentioned features and advantages of the disclosure more comprehensible, the following embodiments are provided, and the accompanying drawings are described in detail as follows. 
     Other objectives, features and advantages of the present invention will be further understood from the further technological features disclosed by the embodiments of the present invention wherein there are shown and described preferred embodiments of this invention, simply by way of illustration of modes best suited to carry out the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a three-dimensional schematic view of a display apparatus according to the first embodiment of the disclosure. 
         FIG.  2    is a schematic cross-sectional view of a light adjusting element according to the first embodiment of the disclosure. 
         FIG.  3 A  is a three-dimensional schematic view of a cone according to the first embodiment of the disclosure. 
         FIG.  3 B  is a schematic front view of a cone according to the first embodiment of the disclosure. 
         FIG.  3 C  is a schematic side view of a cone according to the first embodiment of the disclosure. 
         FIG.  3 D  is a schematic bottom view of a cone according to the first embodiment of the disclosure. 
         FIG.  4    shows the relationship between the vertex angle of the cone, the vertex angle of the first prism sheet, the vertex angle of the second prism sheet and the brightness gain ratio of the emergent light of the backlight module according to the first embodiment of the disclosure. 
         FIG.  5    is a schematic cross-sectional view of a display apparatus according to the second embodiment of the disclosure. 
         FIG.  6    is a schematic top view of a second optical microstructure of a light adjusting element according to the second embodiment of the disclosure. 
         FIG.  7    is a schematic cross-sectional view of a display apparatus according to the third embodiment of the disclosure. 
         FIG.  8    is a schematic top view of a second optical microstructure of a light adjusting element according to the third embodiment of the disclosure. 
         FIG.  9    is a three-dimensional schematic view of a display apparatus according to the fourth embodiment of the disclosure. 
         FIG.  10    is a three-dimensional schematic view of a display apparatus according to the fifth embodiment of the disclosure. 
         FIG.  11    is a three-dimensional schematic view of a display apparatus according to the sixth embodiment of the disclosure. 
         FIG.  12 A  is a three-dimensional schematic view of a cone according to the seventh embodiment of the disclosure. 
         FIG.  12 B  is a schematic front view of a cone according to the seventh embodiment of the disclosure. 
         FIG.  12 C  is a schematic side view of a cone according to the seventh embodiment of the disclosure. 
         FIG.  12 D  is a schematic bottom view of a cone according to the seventh embodiment of the disclosure. 
         FIG.  13 A  is a three-dimensional schematic view of a cone according to the eighth embodiment of the disclosure. 
         FIG.  13 B  is a schematic front view of a cone according to the eighth embodiment of the disclosure. 
         FIG.  13 C  is a schematic side view of a cone according to the eighth embodiment of the disclosure. 
         FIG.  13 D  is a schematic bottom view of a cone according to the eighth embodiment of the disclosure. 
         FIG.  14 A  is a three-dimensional schematic view of a cone according to the ninth embodiment of the disclosure. 
         FIG.  14 B  is a schematic front view of a cone according to the ninth embodiment of the disclosure. 
         FIG.  14 C  is a schematic side view of a cone according to the ninth embodiment of the disclosure. 
         FIG.  14 D  is a schematic bottom view of a cone according to the ninth embodiment of the disclosure. 
         FIG.  15 A  is a three-dimensional schematic view of a cone according to the tenth embodiment of the disclosure. 
         FIG.  15 B  is a schematic front view of a cone according to the tenth embodiment of the disclosure. 
         FIG.  15 C  is a schematic side view of a cone according to the tenth embodiment of the disclosure. 
         FIG.  15 D  is a schematic bottom view of a cone according to the tenth embodiment of the disclosure. 
         FIG.  16 A  is a schematic bottom view of a cone according to the eleventh embodiment of the disclosure. 
         FIG.  16 B  is a schematic front view of a cone according to the eleventh embodiment of the disclosure. 
         FIG.  16 C  is a schematic side view of a cone according to the eleventh embodiment of the disclosure. 
         FIG.  17 A  is a schematic bottom view of a cone according to the twelfth embodiment of the disclosure. 
         FIG.  17 B  is a schematic front view of a cone according to the twelfth embodiment of the disclosure. 
         FIG.  17 C  is a schematic side view of a cone according to the twelfth embodiment of the disclosure. 
         FIG.  18 A  is a schematic bottom view of a cone according to the thirteenth embodiment of the disclosure. 
         FIG.  18 B  is a schematic front view of a cone according to the thirteenth embodiment of the disclosure. 
         FIG.  18 C  is a schematic side view of a cone according to the thirteenth embodiment of the disclosure. 
         FIG.  19 A  is a schematic bottom view of a cone according to the fourteenth embodiment of the disclosure. 
         FIG.  19 B  is a schematic front view of a cone according to the fourteenth embodiment of the disclosure. 
         FIG.  19 C  is a schematic side view of a cone according to the fourteenth embodiment of the disclosure. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The foregoing and other technical content, features and effects of this disclosure will be clearly presented in the following detailed description of the preferred embodiment with reference to the drawings. In this regard, directional terminology, such as “top,” “bottom,” “left,” “right,” “front,” “back,” etc., is used only with reference to the orientation of the Figure(s) being described. As such, the directional terminology is used for purposes of illustration and is in no way limiting. 
     Reference will now be made in detail to the exemplary embodiments of the disclosure, and examples of the exemplary embodiments are illustrated in the accompanying drawings. Whenever possible, the same component symbols are used in the drawings and descriptions to indicate the same or similar parts. 
       FIG.  1    is a three-dimensional schematic view of a display apparatus according to the first embodiment of the disclosure. Please refer to  FIG.  1   , the display apparatus  10  includes a backlight module  100  and a display panel  200 . The display panel  200  is disposed on the backlight module  100 . The display panel  200  may include, for example, a pixel array substrate  210 , an opposite substrate  220 , and a non-self-luminous display medium  230 . The pixel array substrate  210  and the counter substrate  220  are disposed opposite to each other, and the non-self-luminous display medium  230  is disposed between the pixel array substrate  210  and the opposite substrate  220 . For example, in this embodiment, the non-self-luminous display medium  230  may be liquid crystal, but the disclosure is not limited thereto. 
     The backlight module  100  includes a light-emitting element  110 , which is adaptable for emitting a blue light L B . For example, in this embodiment, the light-emitting element  110  is a mini-LED; however, the disclosure is not limited thereto. In other embodiments, the light-emitting element  110  may also be of other sizes and/or types. 
     The backlight module  100  further includes a quantum dot film  120  disposed on the transmitting path of the blue light L B , and is adaptable for converting the first portion L B1  and the second portion L B2  of the blue light L B  into a red light L R  and a green light L G , respectively. The quantum dot film  120  is disposed on a transmitting path of third portion L B3  of the blue light L B , but the third portion L B3  is not converted by the quantum dot film  120 . The red light L R  converted from the first portion L B1  of the blue light L B , the green light L G  converted from the second portion L B2  of the blue light L B  and the third portion L B3  which is not converted from the blue light L B  are mixed to form a white light Lw. 
     The backlight module  100  further includes a light adjusting element  130 , which is disposed between at least one optical film  140  and the quantum dot film  120 . The light adjusting element  130  has a first surface  130   a  and a second surface  130   b  facing the quantum dot film  120  and the at least one optical film  140 , respectively. 
       FIG.  2    is a schematic cross-sectional view of a light adjusting element according to the first embodiment of the disclosure. Referring to  FIG.  1    and  FIG.  2   , it should be noted that the first surface  130   a  of the light adjusting element  130  has multiple first optical microstructures MS1, and the multiple first optical microstructures MS1 include multiple cones  131  protruding toward the quantum dot film  120 . In this embodiment, the multiple cones  131  may be arranged in an array in the first direction d1 and the second direction d2, and the first direction d1 and the second direction d2 are staggered. For example, in this embodiment, the first direction d1 and the second direction d2 can be optionally perpendicular to each other, but the disclosure is not limited thereto. 
     It should be mentioned that the light field of the white light Lw from the quantum dot film  120  is a Lambertian type. That is, part of the white light Lw from the quantum dot film  120  has a large divergence angle φ. Through the refraction and reflection of the cone  131 , part of the white light Lw with a large divergence angle φ can be guided to the positive direction n. In this way, the white light Lw from the quantum dot film  120  can be fully utilized to achieve the effect of improving the brightness of emergent light from the backlight module  100 . 
     In addition, returning to  FIG.  1   , the backlight module  100  further includes at least one optical film  140  disposed on the quantum dot film  120 . For example, in this embodiment, at least one optical film  140  may include a first prism sheet  141 , a second prism sheet  142 , and a diffuser  143  that are arranged in sequence above the quantum dot film  120 . The first prism sheet  141  is disposed between the second prism sheet  142  and the light adjusting element  130 , and the light adjusting element  130  is disposed between the first prism sheet  141  and the quantum dot film  120 . The second prism sheet  142  is disposed between the diffuser  143  and the first prism sheet  141 , and the diffuser  143  is disposed between the display panel  200  and the second prism sheet  142 . The first prism sheet  141  has multiple first prism columns  141   a  extending in the third direction d3, and the second prism sheet  142  has multiple second prism columns  142   a  extending in the fourth direction d4, and the third direction d3 is staggered with the fourth direction d4. In this embodiment, the third direction d3 and the fourth direction d4 can be optionally perpendicular to each other, but the disclosure is not limited thereto. In addition, the disclosure provides no limitation to the type, number, and configuration of the at least one optical film  140 ; in other embodiments, the at least one optical film  140  may also include optical films of other types, other quantities, and/or other configurations. 
       FIG.  3 A  is a three-dimensional schematic view of a cone according to the first embodiment of the disclosure.  FIG.  3 B  is a schematic front view of a cone according to the first embodiment of the disclosure.  FIG.  3 C  is a schematic side view of a cone according to the first embodiment of the disclosure.  FIG.  3 D  is a schematic bottom view of a cone according to the first embodiment of the disclosure. 
     Please refer to  FIG.  1    and  FIG.  3 A  to  FIG.  3 D . In this embodiment, each cone  131  has a bottom surface  131   a , multiple side surfaces  131   c , and a vertex  131   p . The bottom surface  131   a  and the vertex  131   p  are arranged opposite to each other. The vertex  131   p  is closer to the quantum dot film  120 . The bottom surface  131   a  is farther away from the quantum dot film  120 . The multiple side surfaces  131   c  are disposed between the bottom surface  131   a  and the vertex  131   p . Both sides  131   e  of each side surface  131   c  connected to the vertex  131   p  have an angle θ, and a range of the angle θ from 5° to 175°. Preferably, a range of the angle θ from 60° to 100°, but this disclosure is not limited thereto. 
     In this embodiment, the multiple side surfaces  131   c  of each cone  131  include a first side surface  131   c - 1  and a second side surface  131   c - 2  adjacent to each other. Both sides  131   e  of the first side surface  131   c - 1  connected to the vertex  131   p  form a first angle θ1, and both sides  131   e  of the second side surface  131   c - 2  connected to the vertex  131   p  form a second angle θ2. In the embodiment, the first angle θ1 and the second angle θ2 can be optionally the same, but the disclosure is not limited thereto. 
     In addition, in this embodiment, the bottom surface  131   a  of each cone  131  may be optionally polygonal. That is to say, in this embodiment, each cone  131  can optionally be a polygonal pyramid. For example, in this embodiment, the bottom surface  131   a  of each cone  131  may be a square, and each cone  131  may be a square cone. However, this disclosure is not limited thereto. In other embodiments, the cone  131  may also have other shapes, which will be described in the following paragraphs with reference to other drawings. 
     In addition, each cone  131  has a height H in the positive direction n (marked in  FIG.  1   ). In this embodiment, the multiple heights H of the multiple cones  131  can be substantially equal. However, the disclosure is not limited thereto. In other embodiments, the multiple heights H of the multiple cones  131  may not be equal. 
       FIG.  4    shows the relationship between the vertex angle of the cone, the vertex angle of the first prism sheet, the vertex angle of the second prism sheet and the brightness gain ratio of the backlight module according to an embodiment of the disclosure. Please refer to  FIG.  1   ,  FIG.  3 B  and  FIG.  4   , the vertex angle of the cone  131  referred to in  FIG.  4    is the angle θ (marked in  FIG.  3 B ). The vertex angle of the first prism sheet  141  referred to in  FIG.  4    is the angle α (marked in  FIG.  1   ) between the two adjacent side surfaces  141  as of the first prism column  141   a . The vertex angle of the second prism sheet  142  referred to in  FIG.  4    is the angle β (marked in  FIG.  1   ) between the two adjacent side surfaces  142  as of the second prism column  142   a . The brightness gain ratio of the backlight module  100  referred to in  FIG.  4    is the ratio of the brightness of emergent light from the backlight module  100  of the embodiment of  FIG.  1    and the brightness of emergent light from the backlight module of the comparative example not shown. The only difference between the backlight module in the comparative example and the backlight module  100  of  FIG.  1    is that the backlight module of the comparative example replaces the light adjusting element  130  of the backlight module  100  of  FIG.  1    with a diffuser. 
     Please refer to  FIG.  1   ,  FIG.  3 B  and  FIG.  4   . It can be obtained from the data in  FIG.  4    that in this embodiment, preferably, a range of the angle of the vertex angle (the angle α) of the first prism sheet  141  and a range of the angle of the vertex angle (the angle β) of the second prism sheet  142  from 80° to 110°, and a range of the angle of the vertex angle (the angle θ) of the cone  131  of the light adjusting element  130  from 60° to 100°. In this way, the brightness gain ratio of the backlight module  100  is greater than 1. For example, in this embodiment, it is most preferable to set the angle of the vertex angle (the angle α) of the first prism sheet  141  and the angle of the vertex angle (the angle β) of the second prism sheet  142  to be 90°, and set the angle of the vertex angle (the angle θ) of the cone  131  of the light adjusting element  130  to be 80°, so that the brightness gain ratio of the backlight module  100  has the maximum value, but the disclosure is not limited thereto. 
     It must be noted here that the following embodiments use the element numbers and part of the content of the foregoing embodiments, wherein the same numbers are used to represent the same or similar elements, and the description of the same technical content is omitted. For the description of the omitted parts, reference may be made to the foregoing embodiments, and no repetition is incorporated in the following embodiments. 
       FIG.  5    is a schematic cross-sectional view of a display apparatus according to the second embodiment of the disclosure.  FIG.  6    is a schematic top view of a second optical microstructure of a light adjusting element according to the second embodiment of the disclosure. 
     The display apparatus  10 A and its backlight module  100 A in  FIG.  5    are similar to the display apparatus  10  and its backlight module  100  in  FIG.  1   . The difference between the two is that the light adjusting element  130 A in  FIG.  5    is different from the light adjusting element  130  in  FIG.  1   . 
     Please refer to  FIG.  5    and  FIG.  6   . Specifically, in this embodiment, the second surface  130   b  of the light adjusting element  130 A has multiple second optical microstructures MS2, and the shape of each of the multiple first optical microstructures MS1 is different from the shape of each of the multiple second optical microstructures MS2. With the second optical microstructure MS2 of the light adjusting element  130 A, it is possible to prevent the light adjusting element  130 A from being attracted to the at least one optical film  140  above it. In addition, the second optical microstructure MS2 can also avoid interference between the light adjusting element  130 A and the at least one optical film  140 . 
     For example, in this embodiment, the multiple second optical microstructures MS2 include multiple convex lenses  134  protruding toward the at least one optical film  140 . In this embodiment, the multiple vertical projections of the multiple convex lenses  134  on the quantum dot film  120  can optionally be multiple circles, but the disclosure is not limited thereto. 
       FIG.  7    is a schematic cross-sectional view of a display apparatus according to the third embodiment of the disclosure.  FIG.  8    is a schematic top view of a second optical microstructure of a light adjusting element according to the third embodiment of the disclosure. 
     The display apparatus  10 B and its backlight module  100 B in  FIG.  7    are similar to the display apparatus  10 A and its backlight module  100 A in  FIG.  5   . The difference between the two is the multiple convex lenses  134 B included in the multiple second optical microstructures MS2 of the light adjusting element  130 B in  FIG.  7    are different from the multiple convex lenses  134  included in the multiple second optical microstructures MS2 of the light adjusting element  130 A in  FIG.  5   . Please refer to  FIG.  7    and  FIG.  8   . Specifically, in this embodiment, the multiple convex lenses  134 B protrude toward the at least one optical film  140 , and the multiple vertical projections of the multiple convex lenses  134 B on the quantum dot film  120  can be optionally multiple ovals, but this disclosure is not limited thereto. 
       FIG.  9    is a three-dimensional schematic view of a display apparatus according to the fourth embodiment of the disclosure. The display apparatus  10 C and its backlight module  100 C in  FIG.  9    are similar to the display apparatus  10 A and its backlight module  100 A in  FIG.  5   . The difference between the two is the light adjusting element  130 C in  FIG.  9    is different from the light adjusting element  130 A in  FIG.  5   . 
     Please refer to  FIG.  9   , specifically, in this embodiment, the multiple second optical microstructures MS2 of the light adjusting element  130 C include multiple columns  136  extending in the first direction d1. In this embodiment, the extending direction (i.e., the first direction d1) of the columns  136  of the light adjusting element  130 C is staggered with the extending direction (i.e., the third direction d3) of the first prism columns  141   a  of the first prism sheet  141  to avoid interference between the light adjusting element  130 C and the at least one optical film  140 . In this embodiment, the extending direction (i.e., the first direction d1) of the columns  136  and the extending direction (i.e., the fourth direction d4) of the second prism column  142   a  of the second prism sheet  142  may be the same or may be staggered with each other, the disclosure provides no limitation thereto. 
     Please refer to  FIG.  9   , in this embodiment, the cross section  136   s  of each column  136  perpendicular to the first direction d1 can be optionally a triangle. That is to say, in this embodiment, the column  136  of the light adjusting element  130 C can be a triangular column, but the disclosure is not limited thereto. 
       FIG.  10    is a three-dimensional schematic view of a display apparatus according to the fifth embodiment of the disclosure. The display apparatus  10 D and its backlight module  100 D of  FIG.  10    are similar to the display apparatus  10 C and its backlight module  100 C of  FIG.  9   , and the difference between the two is that the column  136 D of the light adjusting element  130 D of  FIG.  10    is different from the column  136  of the light adjusting element  130 C of  FIG.  9   . 
     Please refer to  FIG.  10   , specifically, in this embodiment, the cross section  136   s D of each column  136 D perpendicular to the first direction d1 may be a part of a circle (for example: a major segment, a minor segment or half round). That is to say, in this embodiment, the column  136 D of the light adjusting element  130 D may be a major segment column, a minor segment column or a half round column, but the disclosure is not limited thereto. 
       FIG.  11    is a three-dimensional schematic view of a display apparatus according to the sixth embodiment of the disclosure. The display apparatus  10 E and its backlight module  100 E of  FIG.  11    are similar to the display apparatus  10  and its backlight module  100  of  FIG.  1   , and the differences between the two will be described below. In the embodiment of  FIG.  1   , the quantum dot film  120  is disposed between the light-emitting element  110  and the light adjusting element  130 . That is to say, the backlight module  100  of  FIG.  1    is a direct type backlight module. In the embodiment of  FIG.  11   , the backlight module  100 E further includes a light guide element  150 , and the quantum dot film  120  is disposed between the light guide element  150  and the light adjusting element  130 , and the light-emitting element  110  is disposed on at least one side of the light guide element  150 . That is to say, the backlight module  100 E of  FIG.  11    is a side light backlight module. 
       FIG.  12 A  is a three-dimensional schematic view of a cone according to the seventh embodiment of the disclosure.  FIG.  12 B  is a schematic front view of a cone according to the seventh embodiment of the disclosure.  FIG.  12 C  is a schematic side view of a cone according to the seventh embodiment of the disclosure.  FIG.  12 D  is a schematic bottom view of a cone according to the seventh embodiment of the disclosure. 
     Referring to  FIG.  12 A  to  FIG.  12 D , in this embodiment, the bottom surface  131   a  of the cone  131 A can optionally be a triangle. That is to say, in this embodiment, the cone  131 A may optionally be a triangular pyramid. The cone  131 A can be used to replace the cone  131  of the backlight module  100 ,  100 A,  100 B,  100 C,  100 D or  100 E of the previous embodiment, and the backlight module formed in this way and the display apparatus including such backlight module also fall within the scope to be protected by the disclosure. 
       FIG.  13 A  is a three-dimensional schematic view of a cone according to the eighth embodiment of the disclosure.  FIG.  13 B  is a schematic front view of a cone according to the eighth embodiment of the disclosure.  FIG.  13 C  is a schematic side view of a cone according to the eighth embodiment of the disclosure.  FIG.  13 D  is a schematic bottom view of a cone according to the eighth embodiment of the disclosure. 
     Please refer to  FIG.  13 A  to  FIG.  13 D , in this embodiment, the bottom surface  131   a  of the cone  131 B can be optionally a pentagon. That is to say, in this embodiment, the cone  131 B may optionally be a pentagonal pyramid. The cone  131 B can be used to replace the cone  131  of the backlight module  100 ,  100 A,  100 B,  100 C,  100 D or  100 E of the foregoing embodiments, and the backlight module formed in this way and the display apparatus including such backlight module also fall within the scope to be protected by the disclosure. 
       FIG.  14 A  is a three-dimensional schematic view of a cone according to the ninth embodiment of the disclosure.  FIG.  14 B  is a schematic front view of a cone according to the ninth embodiment of the disclosure.  FIG.  14 C  is a schematic side view of a cone according to the ninth embodiment of the disclosure.  FIG.  14 D  is a schematic bottom view of a cone according to the ninth embodiment of the disclosure. 
     Please refer to  FIG.  14 A  to  FIG.  14 D , in this embodiment, the bottom surface  131   a  of the cone  131 C may optionally be a hexagon. That is, in the present embodiment, the cone  131 C may optionally be a hexagonal pyramid. The cone  131 C can be used to replace the cone  131  of the backlight module  100 ,  100 A,  100 B,  100 C,  100 D or  100 E of the foregoing embodiments, and the backlight module formed in this way and the display apparatus including such backlight module also fall within the scope to be protected by the disclosure. 
       FIG.  15 A  is a three-dimensional schematic view of a cone according to the tenth embodiment of the disclosure.  FIG.  15 B  is a schematic front view of a cone according to the tenth embodiment of the disclosure.  FIG.  15 C  is a schematic side view of a cone according to the tenth embodiment of the disclosure.  FIG.  15 D  is a schematic bottom view of a cone according to the tenth embodiment of the disclosure. 
     Please refer to  FIG.  15 A  to  FIG.  15 D , in this embodiment, the bottom surface  131   a  of the cone  131 D can optionally be circular, and the side surface  131   c  of the cone  131 D is a curved surface. That is, in the embodiment, the cone  131 D may optionally be a circular cone. The cone  131 D can be used to replace the cone  131  of the backlight module  100 ,  100 A,  100 B,  100 C,  100 D or  100 E of the foregoing embodiments. The backlight module formed in this way and the display apparatus including such backlight module also fall within the scope to be protected by the disclosure. 
       FIG.  16 A  is a schematic bottom view of a cone according to the eleventh embodiment of the disclosure.  FIG.  16 B  is a schematic front view of a cone according to the eleventh embodiment of the disclosure.  FIG.  16 C  is a schematic side view of a cone according to the eleventh embodiment of the disclosure. 
     Please refer to  FIG.  16 A to  16 C . In this embodiment, the cone  131 E has a bottom surface  131   a , multiple side surfaces  131   c  and a vertex  131   p . The bottom surface  131   a  and the vertex  131   p  are disposed opposite to each other, and the multiple side surfaces  131   c  are disposed between the bottom surface  131   a  and the vertex  131   p . The multiple side surfaces  131   c  include a first side surface  131   c - 1  and a second side surface  131   c - 2  adjacent to each other. Both sides  131   e  of the first side surface  131   c - 1  connected to the vertex  131   p  form a first angle θ1, and both sides  131   e  of the second side surface  131   c - 2  connected to the vertex  131   p  form a second angle θ2, and the first angle θ1 and the second angle θ2 are different. The cone  131 E can be used to replace the cone  131  of the backlight module  100 ,  100 A,  100 B,  100 C,  100 D or  100 E of the foregoing embodiments. The backlight module formed in this way and the display apparatus including such backlight module also fall within the scope to be protected by the disclosure. 
       FIG.  17 A  is a schematic bottom view of a cone according to the twelfth embodiment of the disclosure.  FIG.  17 B  is a schematic front view of a cone according to the twelfth embodiment of the disclosure.  FIG.  17 C  is a schematic side view of a cone according to the twelfth embodiment of the disclosure. 
     Please refer to  FIG.  17 A  to  FIG.  17 C , in this embodiment, the cone  131 F includes a pyramid-like cone, the pyramid-like cone has a bottom surface  131   a , a top surface  131   b  and multiple side surfaces  131   c . The bottom surface  131   a  and the top surface  131   b  are disposed opposite to each other. The vertex  131   p  of each pyramid-like cone is located on the top surface  131   b , and the multiple side surfaces  131   c  are disposed between the bottom surface  131   a  and the top surface  131   b . In this embodiment, the top surface  131   b  of the pyramid-like cone is a convex surface, but the disclosure is not limited thereto. The cone  131 F can be used to replace the cone  131  of the backlight module  100 ,  100 A,  100 B,  100 C,  100 D or  100 E of the foregoing embodiments, and the backlight module formed in this way and the display apparatus including such backlight module also fall within the scope to be protected by the disclosure. 
       FIG.  18 A  is a schematic bottom view of a cone according to the thirteenth embodiment of the disclosure.  FIG.  18 B  is a schematic front view of a cone according to the thirteenth embodiment of the disclosure.  FIG.  18 C  is a schematic side view of a cone according to the thirteenth embodiment of the disclosure. 
     Please refer to  FIG.  18 A  to  FIG.  18 C , in this embodiment, the cone  131 G includes multiple pyramid-like cones. The pyramid-like cones of  FIG.  18 A  to  FIG.  18 C  are similar to the pyramid-like cones of  FIG.  17 A  to  FIG.  17 C . The difference between the two is that in the embodiments of  FIG.  18 A  to  FIG.  18 C , the pyramid-like cone further has multiple junction surfaces  131   d , and each junction surface  131   d  is disposed between the multiple side surfaces  131   c  and between the bottom surface  131   a  and the top surface  131   b . In this embodiment, the junction surface  131   d  of the pyramid-like cone is a convex surface, but the disclosure is not limited thereto. The cone  131 G can be used to replace the cone  131  of the backlight module  100 ,  100 A,  100 B,  100 C,  100 D or  100 E of the foregoing embodiments, and the backlight module formed in this way and the display apparatus including such backlight module also fall within the scope to be protected by the disclosure. 
       FIG.  19 A  is a schematic bottom view of a cone according to the fourteenth embodiment of the disclosure.  FIG.  19 B  is a schematic front view of a cone according to the fourteenth embodiment of the disclosure.  FIG.  19 C  is a schematic side view of a cone according to the fourteenth embodiment of the disclosure. 
     Please refer to  FIG.  19 A  to  FIG.  19 C , in this embodiment, the cone  131 H includes multiple pyramid-like cones. The pyramid-like cones of  FIG.  19 A  to  FIG.  19 C  are similar to the pyramid-like cones of  FIG.  18 A  to  FIG.  18 C . The difference between the two is in the embodiments of  FIG.  19 A  to  FIG.  19 C , the top surface  131   b H and the junction surface  131   d H of the pyramid-like cone are flat surfaces, but the disclosure is not limited thereto. The cone  131 H can be used to replace the cone  131  of the backlight module  100 ,  100 A,  100 B,  100 C,  100 D or  100 E of the foregoing embodiments, and the backlight module formed in this way and the display apparatus including such backlight module also fall within the scope to be protected by the disclosure. 
     To sum up, a backlight module and a display apparatus according to an embodiment of the disclosure include a light-emitting element adaptable for emitting a blue light, a quantum dot film adaptable for converting the first portion and the second portion of the blue light into red light and green light, respectively, at least one optical film arranged on the quantum dot film, and a light adjusting element arranged between the at least one optical film and the quantum dot film. The light adjusting element has a first surface and a second surface facing the quantum dot film and the at least one optical film respectively. Specifically, the first surface of the light adjusting element has multiple first optical microstructures, and the multiple first optical microstructures include multiple cones protruding toward the quantum dot film. Through the refraction and reflection of the cone, part of the white light with a large divergence angle from the quantum dot film can be guided to the positive direction. In this way, the white light from the quantum dot film can be fully utilized to achieve the effect of enhancing the brightness of emergent light by the backlight module. 
     The foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form or to exemplary embodiments disclosed. Accordingly, the foregoing description should be regarded as illustrative rather than restrictive. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments are chosen and described in order to best explain the principles of the invention and its best mode practical application, thereby to enable persons skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use or implementation contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Therefore, the term “the invention”, “the present invention” or the like does not necessarily limit the claim scope to a specific embodiment, and the reference to particularly preferred exemplary embodiments of the invention does not imply a limitation on the invention, and no such limitation is to be inferred. The invention is limited only by the spirit and scope of the appended claims. Moreover, these claims may refer to use “first”, “second”, etc. following with noun or element. Such terms should be understood as a nomenclature and should not be construed as giving the limitation on the number of the elements modified by such nomenclature unless specific number has been given. The abstract of the disclosure is provided to comply with the rules requiring an abstract, which will allow a searcher to quickly ascertain the subject matter of the technical disclosure of any patent issued from this disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Any advantages and benefits described may not apply to all embodiments of the invention. It should be appreciated that variations may be made in the embodiments described by persons skilled in the art without departing from the scope of the present invention as defined by the following claims. Moreover, no element and component in the present disclosure is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims.