PATENT DOCUMENT

Publication Number: US-9316860-B2
Application Number: US-201314137383-A
Country: US
Kind Code: B2

Title: Electronic device display with damage-resistant polarizer

Abstract:
A display polarizer may have a polymer layer such as a polyvinyl alcohol layer coated with a dichroic dye such as iodine. A polymer layer such as a tri-acetyl cellulose layer may be formed on the polyvinyl alcohol layer so that the iodine is interposed between the polyvinyl alcohol layer and the tri-acetyl cellulose layer. To provide protection for the iodine layer, an additional polymer layer such as an additional tri-acetyl cellulose layer and a layer of adhesive may be formed on top of the polymer layer. A functional layer such as an antireflection layer may form an outermost layer in the polarizer. Compensation films may be formed beneath the polyvinyl alcohol layer. Additional display layers such as a lower polarizer layer and interposed layers such as a thin-film transistor layer, liquid crystal layer, and color filter layer may be formed below the compensation films.

Claims:
What is claimed is: 
     
       1. A polarizer, comprising:
 a first polymer layer, wherein the first polymer layer comprises a polyvinyl alcohol layer; 
 a dichroic dye on the first polymer layer; 
 a second polymer layer, wherein the second polymer layer comprises a tri-acetyl cellulose layer, and wherein the dichroic dye is interposed between the first and second polymer layers; 
 a pressure sensitive adhesive layer on the second polymer layer, wherein the pressure sensitive adhesive layer has a thickness of 5-40 microns; 
 a third polymer layer on the pressure sensitive adhesive layer, wherein the third polymer layer comprises a tri-acetyl cellulose, wherein the second polymer layer has a thickness of 20-80 microns and wherein the third polymer layer has a thickness of 20-80 microns; and 
 an outermost layer on the third polymer layer. 
 
     
     
       2. The polarizer defined in  claim 1  wherein the outermost layer comprises an inorganic layer. 
     
     
       3. The polarizer defined in  claim 1  wherein the outermost layer comprises an antireflection layer. 
     
     
       4. The polarizer defined in  claim 1  further comprising compensation films coupled to the first polymer layer. 
     
     
       5. A polarizer, comprising:
 a polyvinyl alcohol layer; 
 a dichroic dye on the polyvinyl alcohol layer; 
 a tri-acetyl cellulose layer, wherein the dichroic dye is interposed between the polyvinyl alcohol layer and the tri-acetyl cellulose layer; 
 a polymer layer; 
 an adhesive layer between the tri-acetyl cellulose layer and the polymer layer; and 
 a hard coat layer between the tri-acetyl cellulose layer and the adhesive layer, wherein the hard coat layer forms a coating on the polymer layer. 
 
     
     
       6. The polarizer defined in  claim 5 , wherein the adhesive layer comprises a pressure sensitive adhesive layer. 
     
     
       7. The polarizer defined in  claim 5  wherein the tri-acetyl cellulose layer has a thickness of 20-80 microns. 
     
     
       8. The polarizer defined in  claim 7  wherein the polymer layer has a thickness of 20-80 microns. 
     
     
       9. The polarizer defined in  claim 8  wherein the polymer layer is a layer of tri-acetyl cellulose. 
     
     
       10. The polarizer defined in  claim 9  wherein the adhesive layer has a thickness of 10-30 microns. 
     
     
       11. The polarizer defined in  claim 10  further comprising an antireflection layer on the polymer layer. 
     
     
       12. A display, comprising:
 upper and lower polarizer layers; 
 a thin-film transistor layer between the upper and lower polarizer layers; 
 a color filter layer between the upper and lower polarizer layers; and 
 a layer of liquid crystal material between the thin-film transistor layer and the color filter layer, wherein the upper polarizer layer includes a first polymer layer, a second polymer layer, a dichroic dye on the first polymer layer between the first and second polymer layers, a third polymer layer, and an adhesive layer between the second and third polymer layers, wherein the third polymer layer and the second polymer layer have thicknesses of 20-80 microns. 
 
     
     
       13. The display defined in  claim 12  wherein the first polymer layer comprises a polyvinyl alcohol layer and wherein the second polymer layer comprises a tri-acetyl cellulose layer. 
     
     
       14. The display defined in  claim 13  wherein the dichroic dye comprises iodine, wherein the adhesive layer is formed on the second polymer layer, and wherein the third polymer layer comprises tri-acetyl cellulose. 
     
     
       15. The display defined in  claim 14  wherein the adhesive layer comprises a pressure sensitive adhesive layer.

Description:
BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with displays. 
     Electronic devices often include displays. For example, cellular telephones, computers, and televisions have displays. 
     Displays often include polarizer layers. For example, a liquid crystal display may have a liquid crystal layer and other layers that are sandwiched between an upper polarizer and a lower polarizer. An antireflection coating may be formed on top of the upper polarizer. 
     When electronic devices with displays are used in the field, there is a potential for exposure to foreign particles of material such as dirt particles, food crumbs, sand, or other particles of material. If care is not taken, foreign particles can damage a display. For example, if a foreign particle is compressed between a laptop computer base and its display, an upper polarizer layer on the display may be damaged. This damage can appear as an undesired white spot on the display. 
     It would therefore be desirable to be able to provide electronic devices with displays exhibiting enhanced resistance to damage from exposure to foreign particles. 
     SUMMARY 
     An electronic device may be provided with a display. The display may have a polarizer. The polarizer may form an upper polarizer in a pair of polarizers. Display layers such as a thin-film transistor layer, a color filter layer, and a liquid crystal layer may be interposed between the pair of polarizers. 
     The upper polarizer may have a polymer layer such as a polyvinyl alcohol layer coated with a dichroic dye such as iodine. A polymer layer such as a tri-acetyl cellulose layer may be formed on the polyvinyl alcohol layer so that the iodine is interposed between the polyvinyl alcohol layer and the tri-acetyl cellulose layer. To provide protection for the iodine layer and therefore avoid white spots due to iodine layer damage from localized foreign particle pressure, an additional polymer layer such as an additional tri-acetyl cellulose layer and a layer of adhesive may be formed on top of the polymer layer. 
     A functional layer such as an antireflection layer may form an outermost layer in the upper polarizer. Compensation films may be formed beneath the polyvinyl alcohol layer. Display layers such as a lower polarizer layer and interposed layers such as a thin-film transistor layer, liquid crystal layer, and color filter layer may be formed below the compensation films. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device such as a laptop computer with display structures in accordance with an embodiment. 
         FIG. 2  is a perspective view of an illustrative electronic device such as a handheld electronic device with display structures in accordance with an embodiment. 
         FIG. 3  is a perspective view of an illustrative electronic device such as a tablet computer with display structures in accordance with an embodiment. 
         FIG. 4  is a perspective view of an illustrative electronic device such as a display for a computer or television with display structures in accordance with an embodiment. 
         FIG. 5  is a cross-sectional side view of an illustrative display in accordance with an embodiment. 
         FIG. 6  is a cross-sectional side view of layers in an illustrative polarizer in accordance with an embodiment. 
         FIG. 7  is a cross-sectional side view of an electronic device having a hinged lid that is compressing a foreign particle between a base structure and the exposed outer surface of a display in accordance with an embodiment. 
         FIG. 8  is a cross-sectional side view of a portion of a display in which a foreign particle is generating damage to a polarizer layer. 
         FIG. 9  is a cross-sectional side view of a portion of a display that is resistant to foreign particle damage in accordance with an embodiment. 
         FIG. 10  is a cross-sectional side view of layers associated with a polarizer that is resistant to foreign particle damage in accordance with an embodiment. 
         FIG. 11  is a cross-sectional side view of an alternative set of layers associated with a polarizer that is resistant to foreign particle damage in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may be provided with displays. The displays may include polarizers. To help prevent damage to a display that might result in undesirable visible artifacts on the display, the display may be provided with a configuration that helps prevent sensitive layers such as a polyvinyl alcohol layer and an iodine coating on the polyvinyl alcohol layer from experiencing localized pressure due to the presence of foreign particles on the surface of the display. 
     Illustrative electronic devices of the types that may be provided with displays having polarizers with damage-resisting structures are shown in  FIGS. 1, 2, 3, and 4 . 
     Electronic device  10  of  FIG. 1  has the shape of a laptop computer and has upper housing  12 A and lower housing  12 B with components such as keyboard  16  and touchpad  18 . Device  10  has hinge structures  20  (sometimes referred to as a clutch barrel) to allow upper housing  12 A to rotate in directions  22  about rotational axis  24  relative to lower housing  12 B. Display  14  is mounted in housing  12 A. Upper housing  12 A, which may sometimes be referred to as a display housing or lid, is placed in a closed position by rotating upper housing  12 A towards lower housing  12 B about rotational axis  24 . 
       FIG. 2  shows an illustrative configuration for electronic device  10  based on a handheld device such as a cellular telephone, music player, gaming device, navigation unit, or other compact device. In this type of configuration for device  10 , housing  12  has opposing front and rear surfaces. Display  14  is mounted on a front face of housing  12 . Display  14  may have an exterior layer that includes openings for components such as button  26  and speaker port  28 . 
     In the example of  FIG. 3 , electronic device  10  is a tablet computer. In electronic device  10  of  FIG. 3 , housing  12  has opposing planar front and rear surfaces. Display  14  is mounted on the front surface of housing  12 . As shown in  FIG. 3 , display  14  has an opening to accommodate button  26 . 
       FIG. 4  shows an illustrative configuration for electronic device  10  in which device  10  is a computer display, a computer that has an integrated computer display, or a television. Display  14  is mounted on a front face of housing  12 . With this type of arrangement, housing  12  for device  10  may be mounted on a wall or may have an optional structure such as support stand  30  to support device  10  on a flat surface such as a table top or desk. 
     Display  14  may be a liquid crystal display, an organic light-emitting diode display, a plasma display, an electrophoretic display, an electrowetting display, a display using other types of display technology, or a display that includes display structures formed using more than one of these display technologies. Display  14  may include one or more polarizers. For example, an organic light-emitting diode display may include a circular polarizer, a liquid crystal display may have upper and lower polarizers, etc. Configurations for display  14  in which display  14  is a liquid crystal display are sometimes described herein as an example. This is merely illustrative. Display  14  may be formed using any suitable type of display technology. 
     A cross-sectional side view of an illustrative configuration for display  14  of device  10  (e.g., a liquid crystal display for the devices of  FIG. 1 ,  FIG. 2 ,  FIG. 3 ,  FIG. 4  or other suitable electronic devices) is shown in  FIG. 5 . As shown in  FIG. 5 , display  14  may include backlight structures such as backlight unit  42  for producing backlight  44 . During operation, backlight  44  travels outwards (vertically upwards in dimension Z in the orientation of  FIG. 5 ) and passes through display pixel structures in display layers  46 . This illuminates any images that are being produced by the display pixels for viewing by a user. For example, backlight  44  may illuminate images on display layers  46  that are being viewed by viewer  48  in direction  50 . 
     Display layers  46  may be mounted in chassis structures such as a plastic chassis structure and/or a metal chassis structure to form a display module for mounting in housing  12  or display layers  46  may be mounted directly in housing  12  (e.g., by stacking display layers  46  into a recessed portion in housing  12 ). 
     Display layers  46  may include a liquid crystal layer such a liquid crystal layer  52 . Liquid crystal layer  52  may be sandwiched between display layers such as display layers  58  and  56 . Layers  56  and  58  may be interposed between lower (innermost) polarizer layer  60  and upper (outermost) polarizer layer  54 . 
     Layers  58  and  56  may be formed from transparent substrate layers such as clear layers of glass or plastic. Layers  56  and  58  may be layers such as a thin-film transistor layer and/or a color filter layer. Conductive traces, color filter elements, transistors, and other circuits and structures may be formed on the substrates of layers  58  and  56  (e.g., to form a thin-film transistor layer and/or a color filter layer). Touch sensor electrodes may also be incorporated into layers such as layers  58  and  56  and/or touch sensor electrodes may be formed on other substrates. 
     With one illustrative configuration, layer  58  may be a thin-film transistor layer that includes an array of thin-film transistors and associated electrodes (display pixel electrodes) for applying electric fields to liquid crystal layer  52  and thereby displaying images on display  14 . Layer  56  may be a color filter layer that includes an array of color filter elements for providing display  14  with the ability to display color images. If desired, layer  58  may be a color filter layer and layer  56  may be a thin-film transistor layer. 
     During operation of display  14  in device  10 , control circuitry (e.g., one or more integrated circuits on a printed circuit such as integrated circuits  68  on printed circuit  66 ) may be used to generate information to be displayed on display  14  (e.g., display data). The information to be displayed may be conveyed to display driver circuitry such as display driver integrated circuit  62  using a signal path such as a signal path formed from conductive metal traces in a rigid or flexible printed circuit such as printed circuit  64  (as an example). 
     Backlight structures  42  may include a light guide plate such as light guide plate  78 . Light guide plate  78  may be formed from a transparent material such as clear glass or plastic. During operation of backlight structures  42 , a light source such as light source  72  may generate light  74 . Light source  72  may be, for example, an array of light-emitting diodes. 
     Light  74  from light source  72  may be coupled into edge surface  76  of light guide plate  78  and may be distributed in dimensions X and Y throughout light guide plate  78  due to the principal of total internal reflection. Light guide plate  78  may include light-scattering features such as pits or bumps. The light-scattering features may be located on an upper surface and/or on an opposing lower surface of light guide plate  78 . 
     Light  74  that scatters upwards in direction Z from light guide plate  78  may serve as backlight  44  for display  14 . Light  74  that scatters downwards may be reflected back in the upwards direction by reflector  80 . Reflector  80  may be formed from a reflective material such as a layer of white plastic or other shiny materials. 
     To enhance backlight performance for backlight structures  42 , backlight structures  42  may include optical films  70 . Optical films  70  may include diffuser layers for helping to homogenize backlight  44  and thereby reduce hotspots, compensation films for enhancing off-axis viewing, and brightness enhancement films (also sometimes referred to as turning films) for collimating backlight  44 . Optical films  70  may overlap the other structures in backlight unit  42  such as light guide plate  78  and reflector  80 . For example, if light guide plate  78  has a rectangular footprint in the X-Y plane of  FIG. 5 , optical films  70  and reflector  80  may have a matching rectangular footprint. 
     Polarizers such as upper (outermost) polarizer  54  and lower (innermost) polarizer  60  may include a polarizer layer covered with a dichroic layer. As shown in the cross-sectional side view of  FIG. 6 , polarizer  54  (i.e., an upper polarizer in this example) may have a polymer layer such as polarizer film (layer)  102 . Film  102  may be formed from a stretched polymer such as stretched polyvinyl alcohol (PVA) and may therefore sometimes be referred to as a PVA layer. A dichroic dye such as iodine  104  or dichroic organic pigments may be placed on the stretched PVA film to provide polarizer  54  with the ability to polarizer light. When layer  102  is coated with iodine  104 , iodine molecules align with the stretched film and form the polarizer. Other polarizer films may be used if desired. 
     One or more additional polymer layers may be attached to polarizer film  102 . For example, layer  102  may be covered with one or more layers such as protective layer  106  and may have a functional layer  108 . Layer  108  may be the outermost layer in polarizer  54  (and display  14 ). Layers such as protective layer  106  may be formed from a clear polymer. For example, layer  106  may be formed from a material such as tri-acetyl cellulose (TAC) and may sometimes be referred to as a TAC film. The TAC layer or other supporting substrate may help support and protect the PVA film. Functional layer  108  may include one or more layers of organic and/or inorganic material that serve as an antireflection coating, antismudge coating, or antiscratch coating (e.g., a hard coat layer), or may have layers that serve two or more such functions. Other films may be laminated to film  102  if desired. For example, lower film(s)  110  may be formed from one or more compensation films (i.e., birefringent films such as cyclic olefin polymer films that help enhance off-axis viewing performance for display  14 ). Interposed adhesive layers may be used to hold some or all of the layers of material in polarizer  54  and other portions of display  14  together. 
     Foreign particles such as particles of dirt, food, sand, or other materials may gather on the surface of display  14  during normal use of device  10  by a user. If care is not taken, foreign particles may be pressed into the surface of polarizer  54 . When a foreign particle is pressed into polarizer  54  in this way, there is a potential for localized pressure to be exerted on PVA film  102  that disrupts layer  104 . Local disturbances to film  102  and resulting localized damage to layer  104  can give rise to undesired white spots or other visible artifacts on display  14 . 
     The possibility for damage to display  14  can be exacerbated when device  10  has a hinged lid such as lid  12 A of the laptop computer of  FIG. 1 . A cross-sectional side view of laptop computer  10  is shown in  FIG. 7 . As shown in  FIG. 7 , lid  12 A may be placed in a closed position against lower housing  12 B. In this configuration, foreign particles such as particle  112  may be trapped between housing  12 A and display  14  in lid  12 A. Particle  112  may press against the surface of display  14  and may potentially damage the polarizer structures of display  14 . 
     Consider, as an example, the scenario of  FIG. 8 . As shown in the cross-sectional side view of  FIG. 8 , particle  112  may press against polarizer structures such as TAC layer  106 . This may create an indentation such as indentation  116  in the surface of TAC layer  106 . In an illustrative configuration for a polarizer, the TAC layer may have a thickness of 40 microns. This thickness is sufficiently thin that the force that is exerted on the upper surface of TAC layer  106  in the vicinity of indentation  116  is transferred to underlying PVA layer  102  and results in indentation  114  in PVA layer  102 . An indentation such as indentation  114  may be significant enough to damage the iodine layer on PVA layer  102  so that the polarizer exhibits a visible white spot where indentation  114  is formed. 
       FIG. 9  is a cross-sectional side view of a polarizer with an illustrative configuration for reducing or eliminating visible artifacts such as white spots in the presence of surface particle  112 . As shown in  FIG. 9 , polarizer structures for polarizer  54  may be provided with additional protective layers such as additional layers  120  and  124 . Layer  120  may be, for example, a polymer layer such as a TAC layer. Layer  124  may be a layer of pressure sensitive adhesive or other soft layer (e.g., a layer of optically clear adhesive that is preferably softer than TAC layer  120 ). With this type of configuration, particle  112  may press against the surface of TAC layer  120 , creating indentation  122 . Layer  120  may have a thickness that is sufficiently thin to allow force associated with the creation of indentation  122  to be transferred to pressure sensitive adhesive layer  124 . As a result, an indentation such as indentation  126  may be formed in pressure sensitive adhesive layer  124  that corresponds to indentation  122  in TAC layer  120 . Pressure sensitive adhesive layer  124  is preferably soft and viscous and therefore flows laterally under the pressure exerted by indentation  126 . Due to the soft and viscous properties of pressure sensitive adhesive layer  124 , pressure sensitive adhesive layer  124  only weakly transfers force from indentation  126  vertically downward to TAC layer  106 . Because little or no force is exerted on TAC layer  106 , only a minimal amount of indentation is created in the surface of TAC layer  106 , as illustrated by the small size of indentation  128  in  FIG. 9 . TAC layer  106  transfers some of the force associated with small indentation  128  downwards to PVA layer  102 , but because the amount of force associated with small indentation  128  is minimal, there is little or no resulting deformation of surface  132  of PVA layer  102 . The polarizer formed from PVA layer  102  and TAC layer  106  (and from the iodine layer or other dichroic dye layer on PVA film  102 ) is therefore defect free in area  130 , despite the presence of particle  122  on the surface of upper TAC layer  120 . 
     If desired, the protective arrangement of  FIG. 9  can be incorporated into a polarizer of the type shown in  FIG. 10 . As shown in the cross-sectional side view of  FIG. 10 , polarizer  54  of  FIG. 10  has a functional layer  108  such as an antireflection coating or other functional layer. Layer  108  may be formed from inorganic layers such as silicon oxide, metal oxides such as aluminum oxide, or other inorganic materials, may be formed from one or more organic layers, etc. (as an example). Films  110  may include compensation films and adhesive to attach the compensation films to each other and to the lower surface of PVA layer  102 . 
     Iodine  104  or other dichroic dye may be formed on PVA layer  102 , between PVA layer  102  and TAC layer  106 . Pressure sensitive adhesive layer  124  and additional TAC layer  120  may form a protective layer that helps prevent damage from particles on display  14  from damaging iodine layer  104  and PVA layer  102 . Functional layer  108  may be formed as a coating on the surface of TAC layer  120 . 
     With one suitable arrangement, functional coating  108  may have a thickness T 1  of about 7 microns (e.g., less than 10 microns, more than 4 microns, 4-10 microns, or other suitable thickness). TAC layer  120  may have a thickness T 2  of about 40 microns (e.g., less than 80 microns, less than 60 microns, less than 50 microns, more than 20 microns, more than 30 microns, 20-80 microns, 20-60 microns, 30-50 microns, or other suitable thickness). Pressure sensitive adhesive layer  124  may have a thickness T 3  of about 20 microns (e.g., less than 40 microns, less than 30 microns, more than 10 microns, more than 5 microns, 5-40 microns, 10-30 microns, or other suitable thickness). TAC layer  106  may have a thickness T 4  of about 40 microns (e.g., less than 80 microns, less than 60 microns, less than 50 microns, more than 20 microns, more than 30 microns, 20-80 microns, 20-60 microns, 30-50 microns, or other suitable thickness). The thicknesses T 2  and T 4  of respective TAC layers  120  and  106  may be equal, may differ by less than 10% with respect to each other, may differ by less than 25% with respect to each other, may differ by more than 25% with respect to each other, or may have other suitable thicknesses (as examples). PVA layer  102  may have a thickness T 5  of about 22 microns (e.g., less than 40 microns, less than 30 microns, more than 5 microns, more than 10 microns, 10-40 microns, 15-30 microns, or other suitable thickness). 
     Films such as TAC films may be incorporated into polarizer  54  that have hard coat layers. A hard coat layer may be formed from an inorganic or organic thin film that provides the underlying TAC film with abrasion resistance. An illustrative polarizer configuration of this type is shown in  FIG. 11 . As with polarizer  54  of  FIG. 10 , polarizer  54  of  FIG. 11  may have has a functional layer  108  such as an antireflection coating or other functional layer. Layer  108  may be formed from inorganic layers and/or inorganic layers. Films  110  may include compensation films and adhesive to attach the compensation films to each other and to the lower surface of PVA layer  102 . 
     Iodine  104  or other dichroic dye may be formed on PVA layer  102  of  FIG. 11 , between PVA layer  102  and TAC layer  106 . Pressure sensitive adhesive layer  124  and additional TAC layer  102  may form a protective layer that helps prevent damage from particles on display  14  from damaging iodine layer  104  and PVA layer  102 . Functional layer  108  may be formed as a coating on the surface of TAC layer  120 . 
     In the  FIG. 11  configuration, TAC layer  106  has a functional coating such as hard coat layer  134  of thickness T 6 . The value of thickness T 6  may be about 7 microns (e.g., less than 10 microns, more than 4 microns, 4-10 microns, or other suitable thickness). Functional coating  108  may have a thickness T 1  of about 7 microns (e.g., less than 10 microns, more than 4 microns, 4-10 microns, or other suitable thickness). TAC layer  120  may have a thickness T 2  of about 40 microns (e.g., less than 80 microns, less than 60 microns, less than 50 microns, more than 20 microns, more than 30 microns, 20-80 microns, 20-60 microns, 30-50 microns, or other suitable thickness). Pressure sensitive adhesive layer  124  may have a thickness T 3  of about 20 microns (e.g., less than 40 microns, less than 30 microns, more than 10 microns, more than 5 microns, 5-40 microns, 10-30 microns, or other suitable thickness). TAC layer  106  may have a thickness T 4  of about 40 microns (e.g., less than 80 microns, less than 60 microns, less than 50 microns, more than 20 microns, more than 30 microns, 20-80 microns, 20-60 microns, 30-50 microns, or other suitable thickness). The thicknesses T 2  and T 4  of respective TAC layers  120  and  106  may be equal, may differ by less than 10% with respect to each other, may differ by less than 25% with respect to each other, may differ by more than 25% with respect to each other, or may have other suitable thicknesses (as examples). PVA layer  102  may have a thickness T 5  of about 22 microns (e.g., less than 40 microns, less than 30 microns, more than 5 microns, more than 10 microns, 10-40 microns, 15-30 microns, or other suitable thickness). 
     In polarizer configurations of the types shown in  FIGS. 10 and 11 , other thicknesses may be used for the layers of material in the polarizer, other polymers can be used in place of the TAC films, PVA films, etc., other deformable adhesive layers can be used in place of pressure sensitive adhesive  124  (e.g., soft optically clear adhesive formed from a cured liquid adhesive precursor material, combinations of pressure sensitive adhesive and other adhesives, etc.), additional layers of material may be added (e.g., additional TAC films, additional adhesive layers, or other additional polymer layers, etc.). The configurations of  FIGS. 10 and 11  are merely illustrative. 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20131220
Publication Date: 20160419
Grant Date: 20160419
Priority Date: 20131220
Inventors: BUCHANAN NICHOLAS C.
THORNTON BRIAN H.
CHEN CHENG
GILDEN CRAIG S.
QI JUN
ROLAND NICHOLAS G.
YIN VICTOR H.
GE ZHIBING
Assignee: APPLE INC
CPC Classifications: [{"code": "G02F1/133528", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B1/111", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B5/305", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/133528", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B1/111", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B1/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/133528", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B1/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B5/305", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B5/3033", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B5/3033", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 53399848