Abstract:
A method of manufacturing a color conversion film includes: providing a substrate having a first surface and a second surface; forming a plurality of first indentations on the first surface and forming a plurality of second indentations on the second surface; forming a plurality of first quantum dot blocks in the first indentations; and forming a plurality of second quantum dot blocks in the second indentations.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a divisional application of U.S. Ser. No. 14/569,120, filed Dec. 12, 2014 the contents of which are hereby incorporated by reference. The patent application Ser. No. 14/569,120 in turn claims the benefit of priority under 35 USC 119 from Taiwanese Patent Application No. 103134107, filed on Sep. 30, 2014. 
     
    
     FIELD 
       [0002]    The disclosure generally relates to display technologies, and particularly to a color conversion film, a display panel using the color conversion film, and a method for manufacturing the same. 
       BACKGROUND 
       [0003]    A display panel usually employs a color filter to convert a backlight to lights with three-primary colors. However, the color filter only lets a light with a specific color through and absorbs the light with the other colors. Thus, a light transmittance of the color filter is low and a lot of backlight is wasted after passing through the color filter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the views. 
           [0005]      FIG. 1  is an isometric view of a first embodiment of a display panel. 
           [0006]      FIG. 2  is a cross-sectional view of the display panel of  FIG. 1 , taken along line II-II. 
           [0007]      FIG. 3  is a cross-sectional view of a second embodiment of a display panel. 
           [0008]      FIG. 4  is a flowchart of an exemplary embodiment of a method to manufacture the display panel of  FIG. 1 . 
           [0009]      FIG. 5  is a cross-sectional view corresponding to block  401  of  FIG. 4 . 
           [0010]      FIG. 6  is a cross-sectional view corresponding to block  402  of  FIG. 4 . 
           [0011]      FIG. 7  is a cross-sectional view corresponding to block  403  of  FIG. 4 . 
           [0012]      FIG. 8  is a cross-sectional view corresponding to block  404  of  FIG. 4 . 
           [0013]      FIG. 9  is a cross-sectional view corresponding to block  405  of  FIG. 4 . 
           [0014]      FIG. 10  is a cross-sectional view corresponding to block  406  of  FIG. 4 . 
           [0015]      FIG. 11  is a cross-sectional view corresponding to block  407  of  FIG. 4 . 
           [0016]      FIG. 12  is a cross-sectional view corresponding to block  408  of  FIG. 4 . 
           [0017]      FIG. 13  is a cross-sectional view corresponding to block  409  of  FIG. 4 . 
           [0018]      FIG. 14  is a flowchart of an exemplary embodiment of a method to manufacture the display panel of  FIG. 3 . 
           [0019]      FIG. 15  is a cross-sectional view corresponding to block  801  of  FIG. 10 . 
           [0020]      FIG. 16  is a cross-sectional view corresponding to block  802  of  FIG. 10 . 
           [0021]      FIG. 17  is a cross-sectional view corresponding to block  803  of  FIG. 10 . 
           [0022]      FIG. 18  is a cross-sectional view corresponding to block  804  of  FIG. 10 . 
           [0023]      FIG. 19  is a cross-sectional view corresponding to block  805  of  FIG. 10 . 
           [0024]      FIG. 20  is a cross-sectional view corresponding to block  806  of  FIG. 10 . 
           [0025]      FIG. 21  is a cross-sectional view corresponding to block  807  of  FIG. 10 . 
           [0026]      FIG. 22  is a cross-sectional view corresponding to block  808  of  FIG. 10 . 
           [0027]      FIG. 23  is a cross-sectional view corresponding to block  809  of  FIG. 10 . 
           [0028]      FIG. 24  is a cross-sectional view corresponding to block  810  of  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION 
       [0029]    It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure. 
         [0030]    The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series and the like. 
         [0031]    The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references can mean “at least one.” 
         [0032]      FIG. 1  illustrates an isometric view of a first embodiment of a display panel  1 .  FIG. 2  illustrates a cross-sectional view of the display panel  1  of  FIG. 1 , taken along line II-II. The display panel  1  defines a number of pixel areas  100 .  FIG. 2  shows three pixel areas  100  for example. The display panel  1  includes a backlight module  10  emitting a backlight and a color conversion film  12  set at a light output side of the backlight module  10 . Each of the pixel areas  100  includes at least a first sub-pixel  101 , a second sub-pixel  102 , and a third sub-pixel  103  to correspondingly emit lights with three-primary colors. The color conversion film  12  defines a number of color conversion areas corresponding to the sub-pixels  101 ,  102 , and  103  to convert the backlight to lights with three-primary colors. In this embodiment, the backlight module  10  is an organic light emitting diode (OLED) array for emitting a blue backlight. 
         [0033]    The color conversion film  12  includes a substrate  120 , a number of indentations  122  defined in the substrate  120 , a number of quantum dot blocks  124  received in the indentations  122 , and a number of passivation layers  125 . 
         [0034]    The substrate  120  is shaped as an elongated thin sheet and includes a first surface  1200  and a second surface  1202  parallel to the first surface  1200 . The indentations  122  are respectively defined in the first surface  1200  and the second surface  1202  and extended towards an interior of the substrate  120 . Positions and sizes of the indentations  122  are corresponding to the sub-pixels  101 ,  102 , and  103 . In this embodiment, the display panel  1  employs three-primary color lights to display the full color image. The first sub-pixel  101  emits a red light. The second sub-pixel  102  emits a green light. The third sub-pixel  103  emits a blue light. 
         [0035]    The substrate  120  is made of transparent hydrophobic polymer. In this embodiment, the indentations  122  include a number of first indentations  1220  corresponding to the first sub-pixels  101  and a number of second indentations  1222  corresponding to the second sub-pixels  102 . Because the backlight module  10  emits the blue light in this embodiment, the blue light emitted out of the third sub-pixel does not need to be converted to the other color light, there is no indentations  122  defined corresponding to the third sub-pixels  103  in the first surface  1200  or the second surface  1202  to accommodate the quantum dot blocks  124 . In this embodiment, a thickness of the substrate  120  is no less than one micrometer and no more than one hundred and fifty micrometers. 
         [0036]    The first indentations  1220  are defined in the first surface  1200 . The second indentations  1222  are defined in the second surface  1202 . The first indentations  1220  do not pass through to the second surface  1202 . A first distance D 1  is defined between a bottom of the first indentations  1220  and the second surface  1202 . The second indentations  1222  do not pass through to the first surface  1200 . A second distance D 2  is defined between a bottom of the second indentations  1220  and the first surface  1200 . Both the first distance D 1  and the second distance D 2  are no more than thirty micrometers. In this embodiment, both of the first indentations  1220  and the second indentations  1222  have a same depth defined along a direction perpendicular to the first surface  1200  and the second surface  1202  and a same width defined along a direction parallel to the first surface  1200  and the second surface  1202 . The depth of the first indentations  1220  and the second indentations  1222  is no more than one hundred micrometers. The width of the first indentations  1220  and the second indentations  1222  is no less than one micrometer and no more than three hundred micrometers. 
         [0037]    The quantum dot blocks  124  are correspondingly received in the first indentations  1220  and the second indentations  1222  to convert the backlight from the backlight module  10  to lights with three-primary colors. The quantum dot blocks  124  are formed in the first indentations  1220  and the second indentations  1222  by an ink-jet printing process, a micro-contact printing process, a screen printing process, or a micro-embossing printing process. 
         [0038]    The quantum dot blocks  124  are made of an inorganic nano-material which can convert the backlight having a wavelength less than a wavelength of a light with a specific color to the light with the specific color. In this embodiment, the quantum dot blocks  124  includes a number of red quantum dot blocks  1240  formed in the first indentations  1220  and a number of green quantum dot blocks  1242  formed in the second indentations  1222 . The red quantum dot blocks  1240  convert the blue backlight to the red light. The green quantum dot blocks  1242  convert the blue backlight to the green light. Thus, most of the blue backlight can pass through the color conversion film  12  and be used to display an image. A backlight availability of the display panel  1  is improved. 
         [0039]    The passivation layers  125  correspondingly cover the first surface  1200  and the second surface  1202  to seal the quantum dot blocks  124  in the first indentations  1220  and the second indentations  1222 . The passivation layers  125  are made of a transparent material. In this embodiment, a thickness of the passivation layer  125  is no less than one micrometer and no more than one hundred micrometers. 
         [0040]    In this embodiment, a light output direction of the backlight module  10  is perpendicular to the first surface  1200  and the second surface  1202 . One of the first surface  1200  or the second surface  1202  is used as a light incident surface of the color conversion film  12 , the other one is used as a light output surface of the color conversion film  12 . 
         [0041]      FIG. 3  illustrates a cross-sectional view of a second embodiment of a display panel  2 . The display panel  2  defines a number of pixel areas  200 .  FIG. 3  shows three pixel areas  200  for example. The display panel  2  includes a backlight module  20  to emit a backlight and a color conversion film  22  set at a light output side of the backlight module  20 . Each of the pixel areas  200  includes at least a first sub-pixel  201 , a second sub-pixel  202 , and a third sub-pixel  203  to correspondingly emit lights with three-primary colors. The color conversion film  22  defines a number of color conversion areas corresponding to the sub-pixels  201 ,  202 , and  203  converts the backlight to lights with three-primary colors. In this embodiment, the backlight module  20  is an organic light emitting diode (OLED) array for emitting a blue backlight. 
         [0042]    The color conversion film  22  includes a substrate  220 , a number of indentations  222  defined in the substrate  220 , a number of quantum dot blocks  224  received in the indentations  222 , and a number of passivation layers  225 . 
         [0043]    The substrate  220  is shaped as an elongated thin sheet and includes a first surface  2200  and a second surface  2202  parallel to the first surface  2200 . The indentations  222  are respectively defined in the first surface  2200  or the second surface  2202  and extended towards an interior of the substrate  220 . Positions and sizes of the indentations  222  are corresponding to the sub-pixels  201 ,  202 , and  203 . In this embodiment, the display panel  2  employs three-primary color lights to display the full color image. The first sub-pixel  201  emits a red light. The second sub-pixel  202  emits a green light. The third sub-pixel  203  emits a blue light. In this embodiment, the indentations  122  have a same depth defined along a direction perpendicular to the first surface  2200  and the second surface  2202  and a width defined along a direction parallel to the first surface  2200  and the second surface  2202 . The depth of the indentations  222  is no more than one hundred micrometers. The width of the indentations  222  is no less than one micrometer and no more than three hundred micrometers. 
         [0044]    The substrate  220  is made of an opaque hydrophobic polymer. In this embodiment, the indentations  222  includes a number of first indentations  2220  corresponding to the first sub-pixels  201 , a number of second indentations  2222  corresponding to the second sub-pixels  202 , and a number of third indentations  2223  corresponding to the third sub-pixels  203 . Each of the first indentations  2220 , the second indentations  2222 , and the third indentations  2223  passes through the substrate  220  from the first surface  2200  to the second surface  2202 . In this embodiment, a thickness of the substrate  220  is no less than one micrometer and no more than one hundred and fifty micrometers. 
         [0045]    The quantum dot blocks  224  are correspondingly received in the first indentations  2220  and the second indentations  2222  to convert the backlight from the backlight module  20  to lights with three-primary colors. Because the backlight module  20  emits the blue light in this embodiment, the blue light emitted out of the third sub-pixel does not need to be converted to a the other color light, there is no quantum dot blocks  224  received in the third indentations  2223 . The third indentations  2223  are empty. The quantum dot blocks  224  are formed in the first indentations  2220  and the second indentations  2222  by an ink-jet printing process, a micro-contact printing process, a screen printing process, or a micro-embossing printing process. 
         [0046]    The quantum dot blocks  224  are made of an inorganic nano-material which can convert the backlight having a wavelength less than a wavelength of a light with a specific color to light with the specific color. In this embodiment, the color conversion film  22  includes a number of red quantum dot blocks  2240  formed in the first indentations  2220  and a number of green quantum dot blocks  2242  formed in the second indentations  2222 . The red quantum dot blocks  2240  convert the blue backlight to the red light. The green quantum dot blocks  2242  convert the blue backlight to green light. The blue backlight passes through the empty third indentations  2223  to emit out of the color conversion film  22 . Thus, most of the blue backlight can pass through the color conversion film  22  and be used to display an image. A backlight availability of the display panel  2  is improved. 
         [0047]    In other embodiments, if the backlight module  20  emits a light having a wavelength less than a wavelength of blue light, the quantum dot blocks  224  can be filled in the third indentations  2223  to convert the backlight to blue light. 
         [0048]    The passivation layers  225  correspondingly cover the first surface  2200  and the second surface  2202  sealing the quantum dot blocks  224  in the first indentations  2220  and the second indentations  2222 . The passivation layers  225  are made of a transparent material. In this embodiment, a thickness of the passivation layer  225  is no less than one micrometer and no more than one hundred micrometers. 
         [0049]    Referring to  FIG. 4 , a flowchart is presented in accordance with an exemplary embodiment of a method to manufacture the first embodiment of the display panel  1  is being thus illustrated. The example method is provided by way of example, as there are a variety of ways to carry out the method. The method described below can be carried out using the configurations illustrated in  FIGS. 1 and 2 , for example, and various elements of these figures are referenced in explaining example method. Each blocks shown in  FIG. 4  represents one or more processes, methods or blocks is by example only and order of the blocks can change according to the present disclosure. The exemplary method can begin at block  401 . 
         [0050]    At block  401 , also referring to  FIG. 5 , a substrate  120  is provided. The substrate  120  is made of transparent hydrophobic polymer. The substrate  120  is shaped as an elongated thin sheet and includes a first surface  1200  and a second surface  1202  parallel to the first surface  1200 . 
         [0051]    At block  402 , also referring to  FIG. 6 , a first mold  30  and a second mold  40  are provided. The first mold  30  is used to form a number of first indentations  1220  on the first surface  1200 . The second mold  40  is used to form a number of second indentations  1222  on the second surface  1202 . The first mold  30  includes a first base board  300  and a number of first bumps  302  extending from a side surface of the first base board  300 . The second mold  40  includes a second base board  400  and a number of second bumps  402  extending from a side surface of the second base board  400 . 
         [0052]    The first mold  30  is set at a side of the substrate  120  facing the first surface  1200 . The first bumps  302  face the first surface  1200  and align with positions of the first indentations  1220  on the first surface  1200 . The second mold  40  is set at a side of the substrate  120  facing the second surface  1202 . The second bumps  402  face the second surface  1202  and align with positions of the second indentations  1222  on the second surface  1202 . 
         [0053]    At block  403 , also referring to  FIG. 7 , the first mold  30  and the second mold  40  are heated to a molding temperature and then press the substrate  120  correspondingly from the first surface  1200  and the second surface  1202  to form the first indentations  1220  in the first surface  1200  and the second indentations  1222  in the second surface  1202 . The molding temperature is not less than a phase-transition temperature of the substrate  12  transforming from a solid phase to a liquid phase. Because the first indentations  1220  and the second indentations  1222  do not pass through the substrate  12  in the first embodiment of display panel  1 , the first bumps  302  keep a first distance D 1  away from the second surface  1202 , and the second bumps  402  keep a second distance D 2  away from the first surface  1200 . Both of the first distance D 1  and the second distance D 2  are no more than thirty micrometers. 
         [0054]    At block  404 , also referring to  FIG. 8 , the first mold  30  is removed to expose the first indentations  1220  formed on the first surface  1200 . 
         [0055]    At block  405 , also referring to  FIG. 9 , a number of red quantum dot blocks  1240  are formed in the first indentations  1220 . The red quantum dot blocks  1240  are formed in the first indentations  1220  by an ink-jet printing process, a micro-contact printing process, a screen printing process, or a micro-embossing printing process. The red quantum dot blocks  1240  are cured after being formed in the first indentations  1220 . 
         [0056]    Also block  406 , also referring to  FIG. 10 , a passivation layer  125  is formed on the first surface  1200  to seal the red quantum dot blocks  1240  in the first indentations  1220 . 
         [0057]    At block  407 , also referring to  FIG. 11 , the substrate  120  with the second mold  40  is turned over. The second mold  40  is removed to expose the second indentations  1222  on the second surface  1202 . 
         [0058]    At block  408 , also referring to  FIG. 12 , a number of green quantum dot blocks  1242  are formed in the second indentations  1222 . The green quantum dot blocks  1242  are formed in the second indentations  1222  by an ink-jet printing process, a micro-contact printing process, a screen printing process, or a micro-embossing printing process. The green quantum dot blocks  1242  are cured after being formed in the second indentations  1222 . 
         [0059]    At block  409 , also referring to  FIG. 13 , the other passivation layer  125  is formed on the second surface  1202  to seal the green quantum dot blocks  1242  in the second indentations  1222 . 
         [0060]    Referring to  FIG. 14 , a flowchart is presented in accordance with an exemplary embodiment of a method to manufacture the first embodiment of the display panel  2  is being thus illustrated. The example method is provided by way of example, as there are a variety of ways to carry out the method. The method described below can be carried out using the configurations illustrated in  FIGS. 1 and 3 , for example, and various elements of these figures are referenced in explaining example method. Each blocks shown in  FIG. 14  represents one or more processes, methods or blocks is by example only and order of the blocks can change according to the present disclosure. The exemplary method can begin at block  801 . 
         [0061]    At block  801 , also referring to  FIG. 15 , a substrate  220  is provided. The substrate  220  is made of opaque hydrophobic polymer. The substrate  220  is shaped as an elongated thin sheet and includes a first surface  2200  and a second surface  2202  parallel to the first surface  2200 . 
         [0062]    At block  802 , also referring to  FIG. 16 , a first mold  50  and a second mold  60  are provided. The first mold  50  is used to form a number of first indentations  2220  on the first surface  2200 . The second mold  60  is used to form a number of second indentations  2222  on the second surface  2202 . The first mold  50  includes a first base board  500  and a number of first bumps  502  extending from a side surface of the first base board  500 . The second mold  60  includes a second base board  600  and a number of second bumps  602  extending from a side surface of the second base board  600 . 
         [0063]    The first mold  50  is set at a side of the substrate  220  facing the first surface  2200 . The first bumps  502  face the first surface  2200  and align with positions of the first indentations  2220  on the first surface  2200 . The second mold  60  is set at a side of the substrate  220  facing the second surface  2202 . The second bumps  602  face the second surface  2202  and align with positions of the second indentations  2222  on the second surface  2202 . 
         [0064]    At block  803 , also referring to  FIG. 17 , the first mold  50  and the second mold  60  are heated to a molding temperature and then press the substrate  220  correspondingly from the first surface  2200  and the second surface  2202  to form the first indentations  2220  in the first surface  2200  and the second indentations  2222  in the second surface  2202 . The molding temperature is not less than a phase-transition temperature of the substrate  12  transforming from a solid phase to a liquid phase. Because the first indentations  2220  and the second indentations  2222  pass through the substrate  22  in the second embodiment of display panel  2 , the first bumps  502  contact with the second surface  2202  after the first mold  50  is pressed to the substrate  22 , and the second bumps  602  contact with the first surface  2200  after the second mold  60  is pressed to the substrate  22 . 
         [0065]    At block  804 , also referring to  FIG. 18 , the first mold  50  is removed to expose the first indentations  2220  formed on the first surface  2200 . 
         [0066]    At block  805 , also referring to  FIG. 19 , a number of red quantum dot blocks  2240  are formed in the first indentations  2220 . The red quantum dot blocks  2240  are formed in the first indentations  2220  by an ink-jet printing process, a micro-contact printing process, a screen printing process, or a micro-embossing printing process. The red quantum dot blocks  2240  are cured after being formed in the first indentations  2220 . 
         [0067]    At block  806 , also referring to  FIG. 20 , a passivation layer  225  is formed on the first surface  2200  to seal the red quantum dot blocks  2240  in the first indentations  2220 . 
         [0068]    At block  807 , also referring to  FIG. 21 , the substrate  220  with the second mold  60  are turned over. The second mold  60  is removed to expose the second indentations  2222  on the second surface  2202 . 
         [0069]    At block  808 , also referring to  FIG. 22 , a number of green quantum dot blocks  2242  are formed in the second indentations  2222 . The green quantum dot blocks  2242  are formed in the second indentations  2222  by an ink-jet printing process, a micro-contact printing process, a screen printing process, or a micro-embossing printing process. The green quantum dot blocks  2242  are cured after being formed in the second indentations  2222 . 
         [0070]    At block  809 , also referring to  FIG. 23 , a number of third indentations  2223  are defined in substrate  22  corresponding to positions of the third sub-pixels  203 . 
         [0071]    At block  810 , also referring to  FIG. 24 , the other passivation layer  225  is formed on the second surface  2202  to seal the green quantum dot blocks  2242  in the second indentations  2222 . 
         [0072]    It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the scope of the disclosure or sacrificing all of its material advantages.