Patent Publication Number: US-11656400-B2

Title: Backlight module and electronic device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority benefit of China application serial no. 202110858430.7, filed on Jul. 28, 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 
     The disclosure relates to a module and a device, and more particularly to a backlight module and an electronic device. 
     DESCRIPTION OF RELATED ART 
     A backlight module in an electronic device uses a blue light emitting unit with a light conversion layer to generate white light. With this structure, an edge region of the backlight module is prone to white light color point shift, which results in inconsistent white light performance in the center region and in the edge region of the backlight module. 
     SUMMARY 
     The disclosure provides a backlight module and an electronic device, which help address the problem of white light color point shift in an edge region of a backlight module. 
     According to the embodiments of the disclosure, the backlight module has a main region and a peripheral region near the main region. The backlight module includes a light conversion layer, multiple light conversion patterns, and multiple light emitting units. The light conversion patterns are located in the peripheral region. The light emitting units emit a light beam. A first portion of the light beam emitted from the main region has at least one corresponding position in a CIE 1931 color space. A second portion of the light beam emitted from the peripheral region has at least one corresponding position in the CIE 1931 color space. One among the at least one corresponding position of the first portion of the light beam has corresponding coordinates (x1, y1). One among the at least one corresponding position of the second portion of the light beam has corresponding coordinates (x2, y2). The corresponding coordinates (x1, y1) and the corresponding coordinates (x2, y2) satisfy the following relation: 0≤|x1−x2|≤0.2. 
     According to the embodiments of the disclosure, the electronic device includes the backlight module and a display panel disposed on the backlight module. 
     Embodiments accompanied with drawings are described in detail below to make the aforementioned features and advantages of the disclosure comprehensible. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
         FIG.  1    is a schematic cross-sectional view of an electronic device according to an embodiment of the disclosure. 
         FIG.  2    is a schematic top view of a backlight module in  FIG.  1   . 
         FIG.  3 A  and  FIG.  3 B  are the first partial schematic top views of different regions of a reflecting layer on which multiple light conversion patterns are disposed. 
         FIG.  4 A  and  FIG.  4 B  are the second partial schematic top views of different regions of the reflecting layer on which multiple light conversion patterns are disposed. 
         FIG.  5 A  and  FIG.  5 B  are the third partial schematic top views of different regions of the reflecting layer on which multiple light conversion patterns are disposed. 
         FIG.  6 A  and  FIG.  6 B  are the fourth partial schematic top views of different regions of the reflecting layer on which multiple light conversion patterns are disposed. 
         FIG.  7 A  and  FIG.  7 B  are the fifth partial schematic top views of different regions of the reflecting layer on which multiple light conversion patterns are disposed. 
         FIG.  8    is a schematic cross-sectional view of an electronic device according to another embodiment of the disclosure. 
         FIG.  9    is a partially enlarged schematic view of a backlight module in  FIG.  8   . 
         FIG.  10    is a partial schematic top view of a backlight module according to an embodiment of the disclosure. 
         FIG.  11    is a schematic cross-sectional view of the light conversion pattern. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The disclosure may be understood by referring to the following detailed description in conjunction with the accompanying drawings. It should be noted that, in order to facilitate understanding and for concision of the drawings, only a part of the electronic device/display device is shown in multiple drawings in the disclosure, and certain elements in the drawings are not drawn to actual scale. In addition, the number and size of each element in the drawings are only exemplary and are not used to limit the scope of the disclosure. For example, the relative size, thickness, and location of layers, regions, or structures may be reduced or enlarged for clarity. 
     Certain words will be used to refer to specific elements throughout the specification and the appended claims of the disclosure. People skilled in the art should understand that electronic apparatus manufacturers may refer to same elements under different names. The disclosure does not intend to distinguish between elements having same functions but different names. In the following specification and claims, the words“having” and “including” are open-ended words and thus should be interpreted as “including but not limited to.” 
     Wordings used herein to indicate directions, such as “up,” “down,” “front,” “back,” “left,” and “right,” merely refer to directions in the accompanying drawings. Therefore, the directional wordings are used to illustrate rather than limit the disclosure. It should be understood that when an element or film layer is indicated to be disposed “on” or be “connected to” another element or film layer, the element or film layer may be directly on or be directly connected to another element or film layer, or other elements or film layers may exist therebetween (not directly). In contrast, when an element or film layer is indicated to be “directly on” another element or film layer or “directly connected to” another element or film layer, other elements or film layers do not exist therebetween. 
     The terms “approximately,” “equal to,” “equivalent to,” “same,” “substantially,” or “roughly” referred to herein generally mean within a range of 10% of a given value, or mean a range of 5%, 3%, 2%, 1%, or 0.5% of a given value. In addition, the phrases “in a given range from a first value to a second value” and “within a given range from a first value to a second value” indicate the given range includes the first value, the second value, and other values therebetween. 
     In some embodiments of the disclosure, terms concerning attachments and connections such as “connected,” “interconnected,” and the like, unless defined otherwise, mean two structures directly contact each other, or mean the two structures do not directly contact each other and other structures are disposed therebetween. The terms concerning attachments and connections may also include a relationship in which the two structures are both movable or fixed. In addition, the terms “electrically connected to” and “coupled to” include any direct and indirect electrical connection means. Moreover, the terms such as “first” and “second” mentioned in the specification or the claims are only used to name different elements or to distinguish different embodiments or scopes, and are not intended to limit the upper or lower limit of the number of the elements, nor are they intended to limit the manufacturing order or disposition order of the elements. 
     In the disclosure, an electronic device may include, but not limited to, a display device, an antenna device, a sensing device, a light emitting device, or a splicing device. The electronic device may be a bendable electronic device or a flexible electronic device. The electronic device may include, for example, a liquid crystal layer or a light emitting diode (LED). The light emitting diode may include, for example but not limited to, an organic light emitting diode (OLED), a mini light emitting diode (mini LED), a micro light emitting diode (micro LED), or a quantum dot light emitting diode (QLED or QDLED), fluorescence, phosphors, other suitable materials, or a combination of the above, but the disclosure is not limited thereto. Hereinafter, the display device is used as the electronic device to describe the disclosure, but the disclosure is not limited thereto. 
     The display device of the disclosure may be a non-self-luminous display device, such as a liquid crystal display device, but the disclosure is not limited thereto. Hereinafter, the liquid crystal display device is used as the display device to describe the disclosure, but the disclosure is not limited thereto. 
       FIG.  1    is a schematic cross-sectional view of an electronic device according to an embodiment of the disclosure.  FIG.  2    is a schematic top view of a backlight module in  FIG.  1   .  FIG.  3 A  and  FIG.  3 B  are the first partial schematic top views of different regions of a reflecting layer on which multiple light conversion patterns are disposed.  FIG.  4 A  and  FIG.  4 B  are the second partial schematic top views of different regions of the reflecting layer on which multiple light conversion patterns are disposed.  FIG.  5 A  and  FIG.  5 B  are the third partial schematic top views of different regions of the reflecting layer on which multiple light conversion patterns are disposed.  FIG.  6 A  and  FIG.  6 B  are the fourth partial schematic top views of different regions of the reflecting layer on which multiple light conversion patterns are disposed.  FIG.  7 A  and  FIG.  7 B  are the fifth partial schematic top views of different regions of the reflecting layer on which multiple light conversion patterns are disposed.  FIG.  8    is a schematic cross-sectional view of an electronic device according to another embodiment of the disclosure.  FIG.  9    is a partially enlarged schematic view of a backlight module in  FIG.  8   .  FIG.  10    is a partial schematic top view of a backlight module according to an embodiment of the disclosure.  FIG.  11    is a schematic cross-sectional view of the light conversion pattern. 
     In the embodiments of the disclosure, the same or similar elements will be designated by the same or similar reference numerals, and descriptions thereof will be omitted. In addition, as long as the features in different embodiments do not violate or conflict with the spirit of the disclosure, they may be arbitrarily disassembled, mixed, and matched, and simple equivalent changes and modifications made in accordance with this specification or claims are still within the scope of the disclosure. 
     With reference to  FIG.  1    and  FIG.  2   , an electronic device  1  may include, but not limited to, a backlight module  10  and a display panel  12  disposed on the backlight module  10 . According to different requirements, the electronic device  1  may further include one or more elements or film layers, and details thereof are not repeated herein. 
     The backlight module  10  has a main region A 1  and a peripheral region A 2  near the main region A 1 . In some embodiments, as shown in  FIG.  2   , the peripheral region A 2  is near the main region A 1  and may surround the main region A 1  and be connected to the main region A 1 , but the disclosure is not limited thereto. In some embodiments, the maximum width of the peripheral region A 2  in a direction may be 10% of the maximum width of the backlight module  10  in the same direction. For example, a maximum width W 12  of a side (e.g., the left side) of the peripheral region A 2  in a first direction D 1  may be 10% of a maximum width W 11  of the backlight module  10  in the first direction D 1 . Similarly, the maximum width W 12  of another side (e.g., the right side) of the peripheral region A 2  in the first direction D 1  may be 10% of the maximum width W 11  of the backlight module  10  in the first direction D 1 , and/or a maximum width W 22  of a side (e.g., the upper side) of the peripheral region A 2  in a second direction D 2  may be 10% of a maximum width W 21  of the backlight module  10  in the second direction D 2 . Similarly, the maximum width W 22  of another side (e.g., the lower side) of the peripheral region A 2  in the second direction D 2  may be 10% of the maximum width W 21  of the backlight module  10  in the second direction D 2 . The second direction D 2  and the first direction D 1  are different. For example, the second direction D 2  may be perpendicular to the first direction D 1 . 
     The backlight module  10  may include, but not limited to, a light conversion layer  100 , multiple light conversion patterns  101 , and multiple light emitting units  102  (only one schematically shown in  FIG.  1   ). According to different requirements, the backlight module  10  may further include one or more elements or film layers. For example, the backlight module  10  may include, but not limited to, a reflecting layer  103 , a light guide element  104 , an optical film sheet  105 , an optical film sheet  106 , a circuit board  107 , an adhesive layer  108 , a backing plate  109 , and a plastic frame  110 . 
     If the backlight module  10  includes the plastic frame  110 , the maximum width W 11  of the backlight module  10  in the first direction D 1  refers to the maximum distance between two opposite outer edges of the plastic frame  110  in the first direction D 1 , and the maximum width W 21  of the backlight module  10  in the second direction D 2  refers to the maximum distance between the two opposite outer edges of the plastic frame  110  in the second direction D 2 . If the backlight module  10  does not include the plastic frame  110 , the maximum width W 11  of the backlight module  10  in the first direction D 1  refers to the maximum distance between two opposite outer edges of the backing plate  109  in the first direction D 1 , and the maximum width W 21  of the backlight module  10  in the second direction D 2  refers to the maximum distance between the two opposite outer edges of the backing plate  109  in the second direction D 2 . It should be understood that the maximum width W 12  and the maximum width W 22  of the peripheral region A 2  may be the same or different. 
     In some embodiments, the peripheral region A 2  may include a first region A 21  and a second region A 22 . The first region A 21  is located between the main region A 1  and the second region A 22 . If the backlight module  10  includes the plastic frame  110 , the second region A 22  may be defined by the plastic frame  110 . For example, the second region A 22  is substantially the same as where the plastic frame  110  is located when viewed in the normal direction of the backlight module  10  (e.g., a third direction D 3  perpendicular to the first direction D 1  and the second direction D 2 ). If the backlight module  10  does not include the plastic frame  110 , the second region A 22  is substantially the same as the region between the edge of the light conversion pattern  101  adjacent to the backing plate  109  and the outer edge of the backing plate  109  when viewed, for example, in the third direction D 3 . 
     The light conversion layer  100  may include a mono-layer or multi-layer structure. In some embodiments, the light conversion layer  100  is disposed between the optical film sheet  105  and the light guide element  104 , but the disclosure is not limited thereto. For example, when the light conversion layer  100  is irradiated by a short-wavelength light beam, at least a portion of the short-wavelength light beam (e.g., blue light) may be converted into a long-wavelength light beam (e.g., red light, green light, or yellow light, etc.), but the disclosure is not limited thereto. In some embodiments, the material of the light conversion layer  100  may include, but not limited to, fluorescence, phosphorescence, quantum dots (QD), other suitable materials, or a combination of at least two of the foregoing. In some embodiments, the light conversion layer  100  may be formed on a film before fixed on the light guide element  104 , or may be directly coated on the light guide element  104 . Alternatively, the light conversion layer  100  may be disposed between the light emitting element  102  and the light guide element  104 , or may be disposed in the light guide element  104 , but the disclosure is not limited thereto. 
     The light conversion patterns  101  may be located in the peripheral region A 2 . In some embodiments, the light conversion patterns  101  are disposed on the reflecting layer  103  and are located between the light guide element  104  and the reflecting layer  103 . In some embodiments, a portion of the light conversion pattern  101  may be located in the main region A 1  and near the peripheral region A 2 . For example, the light conversion patterns  101 , when irradiated by a short-wavelength light beam, may convert at least a portion of the short-wavelength light beam (e.g., blue light) into a long-wavelength light beam (e.g., red light, green light, yellow light, or blue light of wavelength longer than the incident light/incident light beam, etc.), but the disclosure is not limited thereto. In some embodiments, the material of the light conversion patterns  101  may include, but not limited to, fluorescence, phosphorescence, quantum dots, other suitable materials, or a combination of at least two of the foregoing. 
     The light emitting units  102  are located in the peripheral region A 2 . Taking an edge-type backlight module as an example, the light emitting units  102  may be disposed near a lateral surface S 1  of the light guide element  104 . In another embodiment, the light emitting units  102  may be disposed near the lateral surface S 1  and a lateral surface S 1 ′ of the light guide element  104  opposite to each other, but the disclosure is not limited thereto. The light emitting units  102  may be disposed on the circuit board  107  and be electrically connected to the circuit board  107 . The light emitting units  102  may include the aforementioned light emitting diode, and details thereof are not repeated herein. 
     The light emitting units  102  can emit a light beam B. For example, the light emitting units  102  may be blue light emitting diodes, and the light beam B is blue. A portion of the light beam B (blue light) from the light emitting units  102  may be converted into yellow light by the light conversion patterns  101  or the light conversion layer  100 , while a portion of the light beam B (blue light) not converted by the light conversion patterns  101  or the light conversion layer  100  may be mixed with the yellow light after conversion to form white light. In detail, a portion of the light beam B from the light emitting units  102  enters the light guide element  104  through the lateral surface S 1  of the light guide element  104 , and is transmitted in the light guide element  104  from the peripheral region A 2  toward the main region A 1  by total internal reflection. Microstructures (not shown) or mesh points (not shown) disposed on a bottom surface S 2  of the light guide element  104  can destroy total internal reflection, such that a portion of the light beam B can be transmitted through a top surface S 3  of the light guide element  104  out of the light guide element  104 . The portion of the light beam B transmitted out of the light guide element  104  may be converted into yellow light by the light conversion layer  100 , and the yellow light after conversion may be mixed with a portion of blue light in the light beam B transmitted out of the light guide element  104  to form white light. On the other hand, for example, another portion of the light beam B from the light emitting units  102  (e.g., a light beam with a large angle) does not enter the light guide element  104  and is transmitted to the light conversion patterns  101 , or enters the light guide element  104  through the lateral surface S 1  and is transmitted out of the light guide element  104  through the bottom surface S 2 , such that the light conversion patterns  101  convert the portion of the light beam B transmitted thereto into yellow light. The portion of the light beam B (blue light) not converted by the light conversion patterns  101  may be mixed with the yellow light after conversion to form white light. 
     The reflecting layer  103  is disposed on the backing plate  109  and between the bottom surface S 2  of the light guide element  104  and the backing plate  109 . The reflecting layer  103  may reflect the light beam B transmitted away from the display panel  12 , which may improve the light utilization rate of the backlight module  10 . In some embodiments, the reflecting layer  103  may include a white reflecting sheet, a white tape, or a metal reflecting sheet; alternatively, the reflecting layer  103  may be disposed on the backing plate  109  through a coating process, but the disclosure is not limited thereto. In some embodiments, the reflecting layer  103  may be further disposed between the lateral surface S 1 ′ of the light guide element  104  away from the light emitting element  102  and the backing plate  109  to improve the light utilization rate of the backlight module  10 . 
     The light guide element  104  is disposed between the reflecting layer  103  and the light conversion layer  100 . In some embodiments, at least one of the bottom surface S 2  and the top surface S 3  of the light guide element  104  may be formed with multiple microstructures (not shown) or multiple mesh points (not shown). In some embodiments, the material of the light guide element  104  may include, but not limited to, plastic, glass, or the like. 
     The optical film sheet  105  and the optical film sheet  106  are disposed on the light conversion layer  100  and are located between the display panel  12  and the light conversion layer  100 . In some embodiments, the optical film sheet  105  and the optical film sheet  106  may respectively be a diffuser sheet and a prism sheet, but the disclosure is not limited thereto. In other embodiments not shown, the backlight module  10  may include, but not limited to, one or more diffuser sheets, one or more prism sheets, and/or one or more other optical film sheets. 
     The circuit board  107  may be attached on the side wall of the backing plate  109  through the adhesive layer  108 , such that the light emitting units  102  face the lateral surface S 1  of the light guide element  104 . In some embodiments, the circuit board  107  may include a printed circuit board, and the adhesive layer  108  may include, but not limited to, a tape or an optical adhesive. 
     The plastic frame  110  may be disposed on the backing plate  109  and carry the display panel  12 . A portion of the plastic frame  110  may be disposed on the outer side of the side wall of the backing plate  109 , and an accommodating space may be formed between the plastic frame  110  and the backing plate  109 , which may allow the light guide element  104 , the light conversion layer  100 , the optical film sheet  105 , and the optical film sheet  106  to be accommodated in the accommodating space between the plastic frame  110  and the backing plate  109 . In some embodiments, the plastic frame  110  may be disposed on the backing plate  109  and carry the display panel  12 , the optical film sheet  105 , and the optical film sheet  106 . A portion of the plastic frame  110  may be disposed on the outer side of the side wall of the backing plate  109 , and an accommodating space may be formed between the plastic frame  110  and the backing plate  109 , which may allow the light guide element  104  and the light conversion layer  100  to be accommodated in the accommodating space. The optical film  105  and the optical film sheet  106  may be disposed between the plastic frame  110  and the display panel  12 . In some embodiments, the plastic frame  110  may be made of an opaque material to shield the elements thereunder. 
     In some embodiments, when the backlight module  10  does not include the plastic frame  110 , the backing plate  109  may carry the display panel  12 , and an accommodating space may be formed between the display panel  12  and the backing plate  109 , which may allow the light guide element  104 , the light conversion layer  100 , the optical film sheet  105 , and the optical film sheet  106  to be accommodated in the accommodating space. 
     The display panel  12  may be disposed above the optical film sheet  106  through the plastic frame  110 . In some embodiments, the display panel  12  may include, but not limited to, a non-self-luminous display panel, such as a liquid crystal display panel. 
     The light beam B may form white light after passing through the light conversion layer  100 . The white light passes through the optical film sheet  105  and the optical film sheet  106  in sequence and may serve as the light source of the display panel  12 . 
     A first portion light beam P 1  emitted from the main region A 1  has at least one corresponding position (chromaticity point) in the CIE 1931 color space. A second portion light beam P 2  emitted from the peripheral region A 2  has at least one corresponding position (chromaticity point) in the CIE 1931 color space. One among the at least one corresponding position of the first portion light beam P 1  of the light beam B has corresponding coordinates (x1, y1). One among the at least one corresponding position of the second portion light beam P 2  of the light beam B has corresponding coordinates (x2, y2). The corresponding coordinates (x1, y1) and the corresponding coordinates (x2, y2) may satisfy the following relation: 0≤|x1−x2|≤0.2. In some embodiments, the corresponding coordinates (x1, y1) and the corresponding coordinates (x2, y2) may further satisfy the following relation: 0≤|y1−y2|≤0.3. 
     Specifically, the light conversion patterns  101  disposed near one or more edges of the backlight module  10  may convert blue light into yellow light. The blue light and the yellow light are mixed to form white light, thereby addressing the problem of white light color point shift in the peripheral region A 2 . In this way, white light performance in the main region A 1  and that in the peripheral region A 2  of the backlight module  10  become consistent and then satisfy 0≤|x1−x2|≤0.2 or further satisfy 0≤|y1−y2|≤0.3. 
     In some embodiments, the corresponding coordinates (x1, y1) and the corresponding coordinates (x2, y2) may further satisfy the following relation: 0≤|x1−x2|≤0.1 or 0≤|x1−x2|≤0.05. In some embodiments, the corresponding coordinates (x1, y1) and the corresponding coordinates (x2, y2) may further satisfy the following relation: 0≤|y1−y2|≤0.15 or 0≤|y1−y2|≤0.05. 
     Display panels in three different sizes are listed in Table 1 below as examples, but it should be understood that Table 1 is only for exemplification and not for limiting the disclosure. In Table 1, the corresponding coordinates (x1, y1) are, for example, a chromaticity point of any place within the range of 12% to 15% of the distance from the edge of the backlight module in the main region of the backlight module. The corresponding coordinates (x2, y2) are, for example, a chromaticity point of any place within the peripheral region of the backlight module near the main region. According to Table 1, the light conversion patterns help make the white light performance in the main region and that in the peripheral region of the backlight module to become consistent. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 screen size 
                 49 inches 
                 55 inches 
                 65 inches 
               
               
                   
               
             
            
               
                 x1 
                 0.260~0.270 
                 0.260~0.272 
                 0.260~0.275 
               
               
                 y1 
                 0.230~0.240 
                 0.230~0.245 
                 0.230~0.243 
               
               
                 x2 
                 0.270~0.296 
                 0.272~0.293 
                 0.270~0.280 
               
               
                 y2 
                 0.255~0.280 
                 0.240~0.276 
                 0.240~0.253 
               
               
                 |x1-x2| 
                 0.000~0.036 
                 0.000~0.033 
                 0.005~0.020 
               
               
                 |y1-y2| 
                 0.015~0.050 
                 0.005~0.046 
                 0.003~0.023 
               
               
                   
               
            
           
         
       
     
     In some embodiments, as shown in  FIG.  3 A  to  FIG.  6 B , the shape of the light conversion pattern  101  may be similar to a circle or an ellipse when viewed from the top, but the disclosure is not limited thereto. In addition, as shown in  FIG.  3 A , the light conversion patterns  101  may include a first light conversion pattern  101 - 1  and a second light conversion pattern  101 - 2 . The first light conversion pattern  101 - 1  is closer to the main region A 1  than the second light conversion pattern  101 - 2 . Taking  FIG.  3 A  as an example, the light emitting units (not shown) are arranged along the second direction D 2 , and a dotted line L 1  may be shown in the top view, starting from any place in the main region A 1  to the peripheral region A 2  and being perpendicular to the second direction D 2  (e.g., parallel to the first direction D 1 ). The light conversion pattern  101  closest to the main region A 1  on this dotted line L 1  serves as the first light conversion pattern  101 - 1 , and the light conversion pattern farthest from the main region A 1  on this dotted line L 1  serves as the second light conversion pattern  101 - 2 . In the top view, the first light conversion pattern  101 - 1  and the second light conversion pattern  101 - 2  may have different widths. For example, a maximum width W 101 - 1  (the maximum width in the first direction D 1 ) of the first light conversion pattern  101 - 1  may be less than a maximum width W 101 - 2  (the maximum width in the first direction D 1 ) of the second light conversion pattern  101 - 2 ). 
     In some embodiments, as shown in  FIG.  3 A  to  FIG.  6 B , the maximum width of the light conversion patterns  101  near the peripheral region A 2  may be greater than the maximum width of the light conversion patterns  101  near the main region A 1 , such that blue light near the periphery region A 2  can be more converted into yellow light to address the problem of white light color point shift. 
     In some embodiments, taking  FIG.  3 A  as an example, the top view shows a dotted line L 2  starting from any place in the main region A 1  to the peripheral region A 2  and being parallel to the second direction D 2 . The light conversion patterns on this dotted line L 2  may substantially have the same maximum width, but the disclosure is not limited thereto. 
     In some embodiments, as shown in  FIG.  3 A  to  FIG.  6 B , the light conversion patterns  101  may be arranged alternately. In other words, an included angle between a direction in which any light conversion pattern  101  and the nearest light conversion pattern  101  are arranged and a direction perpendicular to the arrangement direction of the light emitting units (e.g., the first direction D 1 ) is not equal to 0 degrees or 90 degrees. Taking  FIG.  3 A  as an example, the included angle between an arrangement direction D 4  (or an arrangement direction D 5 ) of the second light conversion pattern  101 - 2  and a light conversion pattern  101 - 3  (or a light conversion pattern  101 - 4 ) and the first direction D 1  is not equal to 0 degrees or 90 degrees. 
     With the design of the alternately arranged light conversion patterns  101  increasing the probability of a traveling light beam in contact with the light conversion patterns  101 , the probability of blue light being converted into yellow light may be increased, and the problem of white light color point shift may thus be addressed. 
     In some embodiments, the reflecting layer  103  may be cut to facilitate the assembly of the reflecting layer  103  and the backing plate  109 . With this structure, as shown in  FIG.  3 A  to  FIG.  6 B , the reflecting layer  103  has an edge C. In some embodiments, the light conversion patterns  101  disposed on the reflecting layer  103  may be cut as shown in  FIG.  3 A  and  FIG.  3 B . In some embodiments, the light conversion patterns  101  disposed on the reflecting layer  103  may not be cut as shown in  FIG.  4 A  and  FIG.  4 B . In some embodiments, the light conversion patterns  101  may be disposed on three edges of the reflecting layer  103 , and one edge of the reflecting layer  103  is not disposed with any light conversion pattern as shown in  FIG.  5 A ,  FIG.  5 B ,  FIG.  6 A , and  FIG.  6 B . In some embodiments, one or all of the light conversion patterns  101  may be strip-shaped as shown in  FIG.  7 A  and  FIG.  7 B . 
     With reference to  FIG.  8    and  FIG.  9   , an electronic device  1 A may include a backlight module  10 A and the display panel  12 . The main difference between the backlight module  10 A and the backlight module  10  in  FIG.  1    is that the backlight module  10 A is a direct-type backlight module. In detail, the backlight module  10 A may include, but not limited to, the light conversion layer  100 , the light conversion patterns  101 , the light emitting units  102 , the reflecting layer  103 , the optical film sheet  105 , the optical film sheet  106 , the backing plate  109 , the plastic frame  110 , and an optical film sheet  111 . 
     In the backlight module  10 A, the light emitting units  102  may be disposed on the reflecting layer  103 , and the reflecting layer  103  may be composed of, but not limited to, the uppermost metal layer of a circuit board or a layer with reflection (e.g., white paint). In some embodiments, the reflecting layer  103  may further extend onto the side wall of the backing plate  109 , and the light converting patterns  101  may be disposed on the reflecting layer  103  corresponding to the side wall of the backing plate  109 . In one embodiment, the light conversion patterns  101  may be arranged into a matrix, and in another embodiment, the light conversion patterns  101  may also be arranged alternately, but the disclosure is not limited thereto. 
     One or more light conversion patterns  101  disposed near the backlight module  10 A may convert a portion of blue light into yellow light, and the unconverted blue light may be mixed with the yellow light to form white light, thereby addressing the problem of white light color point shift in the peripheral region A 2 . In this way, white light performance in the main region A 1  and that in the peripheral region A 2  of the backlight module  10  become consistent and then satisfy 0≤|x1−x2|≤0.2 or further satisfy 0≤|y1−y2|≤0.3. 
     In some embodiments, the light conversion patterns  101  may have the same size (e.g., width), but the disclosure is not limited thereto. 
     With reference to  FIG.  10   , in some embodiments, for example, with the structure of an edge-type backlight module, a gap G between two adjacent ones among the light conversion patterns  101  may be greater than 0 and be less than or equal to half of a distance D between two adjacent ones among the light emitting units  102 . For example, the gap G may be the minimum distance between two adjacent light conversion patterns  101  among the light conversion patterns  101  in the row closest to the light emitting units  102  in the arrangement direction of the light emitting units  102  (e.g., the first direction D 1 ). The distance D refers to the minimum distance between two same sides of two adjacent light emitting units  102  in the first direction D 1  (e.g., from the left side of one to the left side of the other, from the right side of one to the right side of the other, or from the middle of one to the middle of the other of the two adjacent light emitting units  102  as shown in  FIG.  10   ). 
     With the above design, the conversion of the light beam B emitted by the light emitting units  102  into yellow light may be improved, the white light performance between two adjacent light emitting units  102  and in front of the light emitting units  102  may be improved, or the problem of uneven brightness of the backlight module  10  may be addressed. 
     Four screen sizes are listed in Table 2 below as examples, but it should be understood that Table 2 is only for exemplification and not for limiting the disclosure. In Table 2, the gap G of 0 means that the light conversion pattern adopts the strip pattern design as shown in  FIG.  7 A  and  FIG.  7 B . For example, the strip light conversion pattern may be disposed on the edge of the reflecting layer near the light incident side, but the disclosure is not limited thereto. In other embodiments, the strip light conversion pattern may also be disposed on multiple (e.g., two, three, or four) edges of the reflecting layer. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 screen size 
                 27 inches 
                 49 inches 
                 55 inches 
                 65 inches 
               
               
                   
               
             
            
               
                 gap G (mm) 
                 0 
                 2.6 
                 2.6 
                 3.8 
               
               
                   
               
            
           
         
       
     
     With reference to  FIG.  11   , in some embodiments, the cross-sectional shape of the light conversion pattern  101  may be substantially semi-elliptical and have a curved surface, but the disclosure is not limited thereto. For example, the light conversion pattern  101  may be formed on the reflecting layer (not shown in  FIG.  11   ) by printing, spray coating, or the like. According to the cross-sectional view of the light conversion pattern  101 , a maximum thickness TH of the light conversion pattern  101  in the third direction D 3  is, for example, less than or equal to a bottom width WB of the light conversion pattern  101  (e.g., the maximum width in the first direction D 1 ). With this design, the light conversion pattern  101  can generate a relatively even light pattern. If the maximum thickness TH is greater than the bottom width WB, the light pattern generated by the light conversion pattern  101  is more concentrated, making the backlight module prone to chromatic aberration. In some embodiments, TH/WB may fall within the range of 0.01 to 1.0, which means 0.01≤TH/WB≤1.0. 
     Two screen sizes are listed in Table 3 below as examples, but it should be understood that Table 3 is only for exemplification and not for limiting the disclosure. In Table 3, the sizes of the light conversion patterns (e.g., the bottom widths) become increasingly greater from the main region to the peripheral region, which means the bottom width of the third light conversion pattern is greater than the bottom width of the second light conversion pattern, and the bottom width of the second light conversion pattern is greater than the bottom width of the first light conversion pattern. When TH/WB&lt;0.1, the maximum thickness TH of the light conversion pattern is too small, and this may increase the probability of blue light leakage from the edge region and cause chromatic aberration to occur. When TH/WB&gt;1, the maximum thickness TH of the light conversion pattern is too large, which means the light pattern generated by the light conversion pattern is rather concentrated and not diffuse, and the light guide element in a small, thin backlight module structure may be bent due to the relatively larger thickness of the light conversion pattern, which leads to uneven brightness of the backlight module. 
     
       
         
           
               
               
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                   
                   
                 main region ↔ peripheral region 
               
            
           
           
               
               
               
               
               
            
               
                   
                   
                 first light 
                 second light 
                 third light 
               
               
                 screen 
                   
                 conversion 
                 conversion 
                 conversion 
               
               
                 size 
                 project 
                 pattern 
                 pattern 
                 pattern 
               
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 49 
                 maximum thickness TH  
                 52 
                 43 
                 46 
               
               
                 inches 
                 (μm) 
                   
                   
                   
               
               
                   
                 bottom width WB (μm) 
                 456 
                 885 
                 1283 
               
               
                   
                 TH/WB 
                 0.11 
                 0.05 
                 0.035 
               
               
                 65 
                 maximum thickness TH  
                 42 
                 45 
                 37 
               
               
                 inches 
                 (μm) 
                   
                   
                   
               
               
                   
                 bottom width WB (μm) 
                 762 
                 986 
                 1229 
               
               
                   
                 TH/WB 
                 0.055 
                 0.045 
                 0.030 
               
               
                   
               
            
           
         
       
     
     In summary, in the embodiments of the disclosure, one or more light conversion patterns disposed near the backlight module convert a portion of blue light into yellow light, and the unconverted blue light may be mixed with the yellow light to form white light, thereby addressing the problem of white light color point shift in the peripheral region and making white light performance in the main region and that in the peripheral region of the backlight module become consistent. In some embodiments, the width of the light conversion patterns near the peripheral region may be greater than the width of the light conversion patterns near the main region, such that the blue light near the peripheral region can be more converted into yellow light to address the problem of white light color point shift. In some embodiments, with the design of the alternately arranged light conversion patterns increasing the probability for a traveling light beam to contact the light conversion patterns, the probability for blue light to be converted into yellow light may be increased to address the problem of white light color point shift. In some embodiments, the light conversion patterns designed to have gaps therebetween may improve the white light performance between two adjacent light emitting units and in front of the light emitting units, or may address the problem of uneven brightness of the backlight module  10 . In some embodiments, chromatic aberration may be addressed by designing the cross-sectional shape of the light conversion pattern. 
     The above embodiments are only used to illustrate technical solutions of the disclosure and are not intended to limit the disclosure. Although the disclosure has been described in detail with reference to the above embodiments, people of ordinary skill in the art should understand that they may still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents, and such modifications or replacements of corresponding technical solutions do not substantially deviate from the scope of the technical solutions of the embodiments of the disclosure. 
     Although the disclosure has been disclosed in the above embodiments, the embodiments are not intended to limit the disclosure. People skilled in the art may make some changes, replacements, and modifications without departing from the spirit and the scope of the disclosure, and the features between the embodiments may be arbitrarily mixed and matched to form other new embodiments. Moreover, the scope of the disclosure is limited to the processes, machines, manufacture, compositions of matter, means, methods, or steps of the particular embodiments described in the specification. People of ordinary skill in the art may understand the processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed from the disclosure. Those performing substantially the same function or achieving substantially the same result as the corresponding embodiments described herein may be utilized according to the disclosure. Therefore, the appended claims of the disclosure include the above processes, machines, manufacture, compositions of matter, means, methods, or steps. In addition, each claim constitutes a separate embodiment, and the scope of the disclosure also includes a combination of each claim and embodiment. The scope of the disclosure is subject to the definition of the scope of the appended claims.