PATENT DOCUMENT

Publication Number: US-9312517-B2
Application Number: US-201414177681-A
Country: US
Kind Code: B2

Title: Electronic device displays with border masking layers

Abstract:
An electronic device may be provided with a display. The display may have an active area with an array of display pixels and an inactive border region containing metal lines and other support circuitry. The array of display pixels may be formed from organic light-emitting diode structures in an organic-light-emitting diode layer. The display may also include an encapsulant layer on the organic light-emitting diode layer and a substrate layer. An opaque masking layer may be formed in the inactive border region. The opaque masking layer may overlap structures in the inactive border region such as the support circuitry, thereby blocking the support circuitry from view. The opaque masking layer may be formed a glass layer in the display, in part of a polarizer in a display, under a planarization layer, or between other layers in the display.

Claims:
What is claimed is: 
     
       1. A display with an active area and an inactive border, comprising:
 an organic light-emitting diode layer having an array of organic light-emitting diode display pixels in the active area and having support circuitry in the inactive area; and 
 an opaque masking layer in the inactive area that covers the support circuitry. 
 
     
     
       2. The display defined in  claim 1  further comprising a display cover layer, wherein the opaque masking layer is formed on an inner surface of the display cover layer. 
     
     
       3. The display defined in  claim 1  further comprising:
 a display cover layer; and 
 a film on the display cover layer, wherein the opaque masking layer is formed between the film and the display cover layer. 
 
     
     
       4. The display defined in  claim 1  further comprising a circular polarizer, wherein the opaque masking layer is formed between the circular polarizer and the organic light-emitting diode layer. 
     
     
       5. The display defined in  claim 4  further comprising:
 an encapsulant layer; and 
 a substrate layer, wherein the organic light-emitting diode layer is located between the substrate layer and the encapsulant layer and wherein the opaque masking layer is formed between the circular polarizer and the substrate layer. 
 
     
     
       6. The display defined in  claim 4  further comprising:
 an encapsulant layer; and 
 a substrate layer, wherein the organic light-emitting diode layer is located between the substrate layer and the encapsulant layer and wherein the opaque masking layer is formed on the substrate layer between the substrate layer and the organic light-emitting diode layer and wherein the display further comprises a planarization layer that covers the opaque masking layer on the substrate layer. 
 
     
     
       7. The display defined in  claim 1  further comprising:
 a circular polarizer; and 
 an encapsulant layer between the circular polarizer and the organic light-emitting diode layer, wherein the opaque masking layer is formed between the circular polarizer and the encapsulant layer. 
 
     
     
       8. The display defined in  claim 1  further comprising:
 a color filter layer; and 
 an encapsulant layer between the color filter layer and the organic light-emitting diode layer, wherein the opaque masking layer is formed between the color filter layer and the encapsulant layer. 
 
     
     
       9. The display defined in  claim 1  further comprising a polarizer having multiple polarizer sublayers and wherein the opaque masking layer is formed between the multiple polarizer sublayers. 
     
     
       10. The display defined in  claim 9  wherein the polarizer comprises:
 a first polarizer support layer; 
 a second polarizer support layer; 
 a polarizer film between the first and second polarizer support layers; and 
 a retarder, wherein the second polarizer support layer is located between the retarder and the polarizer film and wherein opaque masking layer is located between the first polarizer support layer and the polarizer film. 
 
     
     
       11. The display defined in  claim 9  wherein the polarizer comprises:
 a first polarizer support layer; 
 a second polarizer support layer; 
 a polarizer film between the first and second polarizer support layers; and 
 a retarder, wherein the second polarizer support layer is located between the retarder and the polarizer film and wherein opaque masking layer is located between the polarizer film and the second polarizer support layer. 
 
     
     
       12. The display defined in  claim 9  wherein the polarizer comprises:
 a first polarizer support layer; 
 a second polarizer support layer; 
 a polarizer film between the first and second polarizer support layers; and 
 a retarder, wherein the second polarizer support layer is located between the retarder and the polarizer film and wherein opaque masking layer is located between the second polarizer support layer and the retarder. 
 
     
     
       13. The display defined in  claim 9  wherein the polarizer comprises:
 a first polarizer support layer; 
 a second polarizer support layer; 
 a polarizer film between the first and second polarizer support layers; and 
 a retarder, wherein the second polarizer support layer is located between the retarder and the polarizer film, wherein the retarder includes a first eighth-wave plate and a second eighth-wave plate and wherein opaque masking layer is located between the first eighth-wave plate and the second eighth-wave plate. 
 
     
     
       14. A display with an active area and an inactive border, comprising:
 a display layer having an array of display pixels in the active area and having reflecting metal structures in the inactive border; 
 a reflection suppressing layer that suppresses reflections from the array of display pixels and that overlaps the reflecting metal structures in the inactive border; and 
 an opaque masking layer in the inactive area that is located between the reflection suppressing layer and the display layer. 
 
     
     
       15. The display defined in  claim 14  wherein the array of display pixels comprises an array of organic light-emitting diode display pixels, wherein the display layer comprises an organic light-emitting diode layer, and wherein the display further comprises an encapsulating layer between the reflection suppressing layer and the organic light-emitting diode layer. 
     
     
       16. The display defined in  claim 15  wherein reflection suppressing layer comprises a circular polarizer. 
     
     
       17. The display defined in  claim 15  wherein the reflection suppressing layer comprises a color filter layer having an array of color filter elements of different colors. 
     
     
       18. A display with an active area and an inactive border, comprising:
 an organic light-emitting diode layer having an array of organic light-emitting diode display pixels in the active area and having support circuitry in the inactive area; 
 a polarizer; 
 a substrate between the polarizer and the organic light-emitting diode layer; 
 an opaque masking layer on the substrate in the inactive area that overlaps the support circuitry; and 
 a planarization layer on the substrate that overlaps the opaque masking layer, wherein the organic light-emitting diode layer is formed on the planarization layer. 
 
     
     
       19. The display defined in  claim 18  further comprising an encapsulation layer, wherein the organic light-emitting diode layer is located between the planarization layer and the encapsulation layer. 
     
     
       20. The display defined in  claim 19  wherein the substrate comprises a glass layer and wherein the polarizer comprises a circular polarizer.

Description:
This application claims priority to U.S. provisional patent application No. 61/798,451 filed Mar. 15, 2013, which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     This relates generally to electronic devices, and more particularly, to electronic devices with displays. 
     Electronic devices often include displays. For example, cellular telephones and portable computers often include displays for presenting information to a user. 
     It can be challenging to form displays for electronic devices. Displays such as organic light-emitting diode displays typically include a rectangular array of active display pixels surrounded by an inactive border region filled with metal signal lines and other support circuitry. If care is not taken, undesirable reflections from the support circuitry in the inactive border region will be visible to a user of an electronic device. 
     It would therefore be desirable to be able to provide improved displays for electronic devices. 
     SUMMARY 
     An electronic device may be provided with a display. The display may have an active area with an array of display pixels and an inactive border region containing metal lines and other support circuitry. 
     The array of display pixels may be formed from organic light-emitting diode structures in an organic-light-emitting diode layer. The display may also include an encapsulant layer on the organic light-emitting diode layer and a substrate layer. 
     An opaque masking layer may be formed in the inactive border region. The opaque masking layer may overlap structures in the inactive border region such as the support circuitry, thereby blocking the support circuitry from view. 
     The opaque masking layer may be formed a glass layer in the display, on or within the layers of a polarizer in a display, under a planarization layer, or between other layers in the display. 
     Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device such as a laptop computer with a display in accordance with an embodiment of the present invention. 
         FIG. 2  is a perspective view of an illustrative electronic device such as a handheld electronic device with a display in accordance with an embodiment of the present invention. 
         FIG. 3  is a perspective view of an illustrative electronic device such as a tablet computer with a display in accordance with an embodiment of the present invention. 
         FIG. 4  is a perspective view of an illustrative electronic device such as a computer display with display structures in accordance with an embodiment of the present invention. 
         FIG. 5  is a perspective view of an illustrative display in accordance with an embodiment of the present invention. 
         FIG. 6  is a cross-sectional side view of an electronic device with a display in accordance with an embodiment of the present invention. 
         FIG. 7  is a cross-sectional side view of an illustrative bottom emission organic light-emitting diode display in accordance with an embodiment of the present invention. 
         FIG. 8  is a cross-sectional side view of an illustrative top emission organic light-emitting diode display with a reflection suppression layer formed from a circular polarizer in accordance with an embodiment of the present invention. 
         FIG. 9  is a cross-sectional side view of an illustrative top emission organic light-emitting diode display with a reflection suppression layer formed from a color filter layer in accordance with an embodiment of the present invention. 
         FIG. 10  is a cross-sectional side view of an illustrative display having an opaque masking layer located above or below a display cover layer in accordance with an embodiment of the present invention. 
         FIG. 11  is a cross-sectional side view of an illustrative display with an opaque masking layer located above a film layer that is formed on the top of the display in accordance with an embodiment of the present invention. 
         FIG. 12  is a cross-sectional side view of an illustrative display with an opaque masking layer located below a film layer that is formed on the top of the display in accordance with an embodiment of the present invention. 
         FIG. 13  is a cross-sectional side view of an illustrative bottom emission organic light-emitting diode display with an opaque masking layer located between a polarizer layer and a substrate layer in accordance with an embodiment of the present invention. 
         FIG. 14  is a cross-sectional side view of an illustrative bottom emission organic light-emitting diode display with a black masking layer formed on a substrate layer and covered with a planarization layer in accordance with an embodiment of the present invention. 
         FIG. 15  is a cross-sectional side view of an illustrative top emission organic light-emitting diode display with a masking layer formed above or below a polarizer layer in accordance with an embodiment of the present invention. 
         FIG. 16  is a cross-sectional side view of an illustrative top emission organic light-emitting diode display with a masking layer formed above or below a color filter layer in accordance with an embodiment of the present invention. 
         FIG. 17  is a cross-sectional side view of an illustrative polarizer showing locations in which an opaque masking layer for a display may be formed in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may include displays. The displays may be used to display images to a user. Illustrative electronic devices that may be provided with displays are shown in  FIGS. 1, 2, 3, and 4 . 
       FIG. 1  shows how electronic device  10  may have the shape of a laptop computer having upper housing  12 A and lower housing  12 B with components such as keyboard  16  and touchpad  18 . Device  10  may have hinge structures  20  that allow upper housing  12 A to rotate in directions  22  about rotational axis  24  relative to lower housing  12 B. Display  14  may be mounted in upper housing  12 A. Upper housing  12 A, which may sometimes referred to as a display housing or lid, may be placed in a closed position by rotating upper housing  12 A towards lower housing  12 B about rotational axis  24 . 
       FIG. 2  shows how electronic device  10  may be 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  may have opposing front and rear surfaces. Display  14  may be mounted on a front face of housing  12 . Display  14  may, if desired, have openings for components such as button  26 . Openings may also be formed in display  14  to accommodate a speaker port (see, e.g., speaker port  28  of  FIG. 2 ). 
       FIG. 3  shows how electronic device  10  may be a tablet computer. In electronic device  10  of  FIG. 3 , housing  12  may have opposing planar front and rear surfaces. Display  14  may be mounted on the front surface of housing  12 . As shown in  FIG. 3 , display  14  may have an opening to accommodate button  26  (as an example). 
       FIG. 4  shows how electronic device  10  may be a computer display or a computer that has been integrated into a computer display. With this type of arrangement, housing  12  for device  10  may be mounted on a support structure such as stand  27 . Display  14  may be mounted on a front face of housing  12 . 
     The illustrative configurations for device  10  that are shown in  FIGS. 1, 2, 3, and 4  are merely illustrative. In general, electronic device  10  may be a laptop computer, a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wrist-watch device, a pendant device, a headphone or earpiece device, or other wearable or miniature device, a television, a computer display that does not contain an embedded computer, a gaming device, a navigation device, an embedded system such as a system in which electronic equipment with a display is mounted in a kiosk or automobile, equipment that implements the functionality of two or more of these devices, or other electronic equipment. 
     Housing  12  of device  10 , which is sometimes referred to as a case, may be formed of materials such as plastic, glass, ceramics, carbon-fiber composites and other fiber-based composites, metal (e.g., machined aluminum, stainless steel, or other metals), other materials, or a combination of these materials. Device  10  may be formed using a unibody construction in which most or all of housing  12  is formed from a single structural element (e.g., a piece of machined metal or a piece of molded plastic) or may be formed from multiple housing structures (e.g., outer housing structures that have been mounted to internal frame elements or other internal housing structures). 
     Display  14  may be a touch sensitive display that includes a touch sensor or may be insensitive to touch. Touch sensors for display  14  may be formed from an array of capacitive touch sensor electrodes, a resistive touch array, touch sensor structures based on acoustic touch, optical touch, or force-based touch technologies, or other suitable touch sensor components. 
     Display  14  for device  10  includes display pixels formed from organic light-emitting diode components or other suitable display pixel structures. 
     A display cover layer may cover the surface of display  14  or a display layer such as a color filter layer, polarizer layer, polymer film, or other portion of a display may be used as the outermost (or nearly outermost) layer in display  14 . The outermost display layer may be formed from a transparent glass sheet, a clear plastic layer, or other transparent member. 
     A perspective view of an illustrative display is shown in  FIG. 5 . As shown in  FIG. 5 , display  14  may have an array of display pixels  30 . Control signals may be supplied to display pixels  30  on vertical control lines  32  and horizontal control lines  34 . By controlling display pixels  30 , control circuitry in device  10  may display images for a user of device  10  on display  14 . 
     Display pixels  30  may be arranged in a rectangular array in the center of display  14 . During use of device  10 , display pixels  30  form images, so display pixels  30  in display  14  are sometimes said to form an active area AA of display  14 . Active area AA may be bounded by dashed line rectangle  36  in the example of  FIG. 5 . An inactive area IA may border some or all of the edges of active area AA. For example, a rectangular ring-shaped inactive area IA may form a border that surrounds active area AA, as shown in  FIG. 5 . Display  14  typically includes signal lines (e.g., metal traces) and other support circuitry for operating display  14  (i.e., circuitry for driving signals into display pixels  30 ) in inactive border region IA. The support circuitry in inactive area IA does not produce light for images on display  14 . 
     To prevent structures in inactive area IA from being visible to a user of device  10 , it may be desirable to cover areas IA with an opaque mask. The opaque mask may have the shape of a rectangular ring (i.e., the same shape as inactive area IA in  FIG. 5 ) or may have other suitable shapes. Opaque masking material such as organic materials and/or inorganic materials may be used in forming an opaque masking layer in area IA. Examples of opaque masking material that may be used in forming an opaque masking layer include black chrome (chrome oxide), other metal oxides, black ink, ink of other colors (e.g., white ink, red ink, etc.), polymers, metals, oxides, nanotubes such as carbon nanotubes, black silicon (e.g., black silicon processed using a laser), nitrides, and other opaque materials. Materials such as opaque ink may be deposited using pad printing, screen printing, ink-jet printing, and other deposition techniques. Materials such as metal oxides and other inorganic materials may be deposited using vacuum coating (e.g., physical vapor deposition using an evaporator or sputtering tool). Shadow masking and/or photolithography may be used in patterning deposited masking material. If desired, opaque masking material may also be deposited using lamination techniques. 
       FIG. 6  is a cross-sectional side view of an illustrative electronic device with a display. As shown in  FIG. 6 , device  10  may include housing  12 . Display  14  may be mounted in housing  12 . Display  14  may include an array of display pixels  30  in display structures  38 . Display structures  38  may be based on organic light-emitting diode display structures including layers such as a substrate layer, an encapsulation layer, and an organic light-emitting diode layer containing organic light-emitting diode display pixels  30 . In the example of  FIG. 6 , organic light-emitting diode display layers  38  are attached to the lower surface of an external display layer such as display cover layer  40 . Display cover layer  40  may be formed from a layer of transparent glass, a clear plastic layer, or other transparent member (e.g., one or more clear sheets of material). Display cover layer  40  may help to protect underlying display structures such as organic light-emitting diode display structures  38 . In inactive area IA, display structures  38  (e.g., the organic light-emitting diode layer of structures  38 ) may contain metal lines and other support circuitry  42 . An opaque masking layer may be formed in inactive area IA to block the support circuitry from view. Display pixels  30  may form a rectangular array in active area AA. 
     Device  10  may have internal components  43  mounted on substrate  44 . Components  43  may include integrated circuits such as microprocessors, application-specific integrated circuits, microcontrollers, and other processing circuitry. Components  43  may also include storage circuitry such as memory circuits and other memory devices. Input-output circuitry such as sensors, buttons, and other input-output circuitry may also be included in components  43 . Substrates such as substrate  44  may be used to interconnect the circuitry of components  43 . Substrate  44  may be a rigid printed circuit board (e.g., a fiberglass-filled epoxy board) or a flexible printed circuit (e.g., a printed circuit formed from a flexible substrate such as polyimide or other polymer layer). 
     Display  14  may be based on organic light-emitting diode display pixels or display pixels formed using other display technologies. Configurations for display  14  in which display pixels  30  are formed from organic light-emitting diodes and in which display  14  is an organic light-emitting diode display may sometimes be described herein as an example. This is, however, merely illustrative. Device  10  may, in general, include any suitable type of display. 
     A cross-sectional side view of display  14  in a configuration using a bottom emission organic light-emitting diode display configuration is shown in  FIG. 7 . As shown in  FIG. 7 , bottom emission organic light-emitting diode display  14  may have a substrate layer such as substrate  48 . Substrate  48  may include one or more transparent layers such as one or more glass layers, one or more plastic layers, or other transparent substrate layers. As an example, substrate  48  may be formed from a layer of clear glass. 
     Organic light-emitting diode layer  50  may be formed on substrate  48  (i.e., on the surface of substrate  48  that is the lower or innermost of the two opposing surfaces of substrate  48  in the orientation of  FIG. 7 ). During operation, light from display pixels  30  in organic light-emitting diode layer  50  may pass through substrate  48  (i.e., through substrate layer  48  on which the organic light-emitting diodes, thin-film-transistors, and other organic light-emitting diode circuitry have been formed) in direction Z, as illustrated by light ray  54 . 
     In active area AA, organic light-emitting diode layer  50  includes organic light-emitting diode structures  60  (e.g., anode electrode structures, cathode electrode structures, emissive layers, signal lines, thin-film transistors, etc.). For example, active area organic light-emitting diode structures  60  in organic light-emitting diode layer  50  may include metal structures  62  (e.g., anode and cathode structures and metal traces for signal lines). The light produced by the organic light-emitting diode structures in active area AA of organic light-emitting diode layer  50  such as light ray  54  produces an image for a viewer such as viewer  56  who is viewing display  14  in direction  58 . 
     In inactive area IA, organic light-emitting diode layer  50  includes inactive area organic light-emitting diode display structures such as inactive area structures  64 . Inactive area structures  64  may include support circuitry such as metal traces for signal lines, thin-film circuitry such as driver circuitry, and other circuitry that does not produce light  54  for viewer  56 . For example, inactive area structures  64  of organic light-emitting diode layer  50  may include metal structures such as metal traces for signal lines  66 . 
     To suppress ambient light reflections from metal structures  62  (e.g., from reflective cathode structures in bottom emission display  14 ), display  14  may be provided with a reflection suppressing layer such as circular polarizer layer  46 . Circular polarizer  46  may, if desired, overlap with inactive area IA, as shown in  FIG. 7 . 
     Encapsulant layer  52  may be formed on organic light-emitting diode layer  50  (i.e., on the lower surface of layer  50  in the orientation of  FIG. 7 ). Encapsulant layer  52  may be used to encapsulate the organic light-emitting diode structures of organic light-emitting diode layer  50 . Encapsulant layer  52  may be formed from a glass or plastic layer, may be formed from a glass or plastic layer coated with a thin film such as an inorganic coating, may be formed from a layer of metal (e.g., a metal plate, metal can, or metal foil), or may be formed from a metal coating on a substrate layer such as a glass layer or plastic layer (as examples). If desired, a coating of water-absorbing and/or oxygen absorbing material may be formed on a glass layer or other encapsulant layer to help sequester oxygen and water. As illustrated by dashed line  70 , encapsulant layer  52  may contain two or more sublayers (e.g., a glass plate and a coating, a metal layer on a glass or polymer substrate or other dielectric layer, etc.). 
     A cross-sectional side view of display  14  in a configuration using a top emission organic light-emitting diode display configuration is shown in  FIG. 8 . As shown in  FIG. 8 , top emission organic light-emitting diode display  14  may have a substrate layer such as substrate  90 . Substrate  90  may include one or more transparent layers such as one or more glass layers, one or more plastic layers, or other transparent substrate layers. As an example, substrate  90  may be formed from a layer of glass. 
     Organic light-emitting diode layer  72  may be formed on substrate  90  (i.e., on the upper surface of substrate  90  in the orientation of  FIG. 8 ). During operation, light from display pixels  30  in organic light-emitting diode layer  72  may pass upwards in Z, as illustrated by light ray  88 . 
     In active area AA, organic light-emitting diode layer  72  includes organic light-emitting diode structures  94  (e.g., anode electrode structures, cathode electrode structures, emissive layers, signal lines, thin-film transistors, etc.). For example, active area organic light-emitting diode structures  94  in organic light-emitting diode structures layer  72  may include reflective structures  80  (e.g., anode and cathode structures and metal traces for signal lines such as a reflective anode formed from a metal such as aluminum or a metal such as aluminum that has been covered with a coating such as indium tin oxide). The light produced by the organic light-emitting diode structures in active area AA of organic light-emitting diode layer  72  such as light ray  88  produces an image for a viewer such as viewer  56  who is viewing display  14  in direction  58 . 
     In inactive area IA, organic light-emitting diode layer  72  includes inactive area organic light-emitting diode display structures such as inactive area structures  86 . 
     Inactive area structures  86  may include supporting circuitry such as metal traces for signal lines, and other circuitry that does not produce light  88  for viewer  56  but that supports the operation of the display pixels in active area AA. For example, inactive area structures  86  of organic light-emitting diode layer  72  may include metal structures such as metal traces for signal lines  82 . 
     To suppress ambient light reflections from metal structures  80  (e.g., from reflective anode structures in top emission display  14 ), display  14  may be provided with a reflection suppressing layer (reflection suppression layer) such as circular polarizer layer  78 . Circular polarizer  78  may, if desired, overlap inactive area IA and may cover support circuitry  86 , as shown in  FIG. 8 . 
     Encapsulant layer  74  may be formed on layer  72  under polarizer  78  and may be used to encapsulate the organic light-emitting diode structures of organic light-emitting diode layer  72 . Encapsulant layer  74  may be formed from a transparent material such as a clear glass layer, a clear layer of polymer, a clear inorganic thin-film, or other clear materials. As an example, layer  74  may be formed from a sheet of transparent glass. As illustrated by dashed line  92 , encapsulant layer  74  may contain two or more sublayers. For example, encapsulant layer  74  may be formed from a glass plate that is covered with an inorganic thin film coating. 
     In illustrative top emission display  14  of  FIG. 9 , color filter layer  96  is used as a reflection suppressing layer. Color filter layer  96  may contain an array of color filter elements  98 . Color filter elements  98  may, for example, be formed from a polymer such as photoresist that has been colored with dye or pigment. With one suitable arrangement, color filter elements  98  include red, blue, and green color filter elements. Organic light-emitting diode layer  72  contains display pixels configured to emit different wavelengths of light (e.g., red, blue, green). 
     The display pixels in organic light-emitting diode structures  94  are aligned with color filter elements  98  of matching colors. For example, red display pixels  30  may be aligned with red color filter elements  98 , blue display pixels  30  may be aligned with blue color filter elements  98 , and green display pixels  30  may be aligned with green color filter elements  98 . In the example of  FIG. 9 , red display pixel RP is aligned with red color filter element R. Incoming ambient light from outside of display  14 , will reach reflective structures such as reflective structures  80  only after passing through a color filter element. Each color filter element may be configured to exhibit a narrow passband that is aligned with a relatively narrow spectral width for emitted light from a respective display pixel. The narrow passband of color filter elements  98  ensures that most incident ambient white light will be absorbed in color filter layer  96 , rather than passing through layer  74  into structures  72  and reflecting off of reflective structures  80 . Outward transmission of light  88  from display pixels  30  is not hindered by the presence of color filter elements  98 , because the pass bands of color filter elements  98  are sufficiently wide to allow the colored light emitted from the matched display pixels to pass without being significantly attenuated. 
     As with circular polarizer  78  of top emission display  14  of  FIG. 8 , color filter layer  96  of top emission display  14  of  FIG. 9  may extend over inactive area IA and may cover support circuitry  86 . 
     To facilitate light reflection suppression in inactive areas IA of displays such as the displays of  FIGS. 7, 8, and 9 , it may be desirable to incorporate one or more layers of patterned opaque masking material (e.g., black material, white material, or other material that is opaque to light) into one or more of the layers of display  14  in inactive area IA. 
     As shown in  FIG. 10 , display layers  100  (e.g., display layers such as the layers of  FIG. 7 ,  FIG. 8 , or  FIG. 9 ) may be covered with an optional display cover layer such as display cover layer  102 . Display cover layer  102  may be formed from a layer of plastic, a clear planar glass layer, or a transparent sheet of other materials. To hide structures in inactive area IA from view by a user of device  10 , display  14  of  FIG. 10  may be provided with an opaque masking layer such as layer  104 . Opaque masking layer  104  may be patterned to form a rectangular ring surrounding the active area AA of display  14  or other suitable mask shapes overlapping inactive area IA. Opaque masking layer  104  may be formed on the top of layers  100  (e.g., on top polarizer  46 , on top of polarizer  78 , or on top of color filter layer  96 ) or may be formed on the underside of display cover layer  102 . 
     If desired, an opaque masking layer in inactive area IA may be formed on top of display cover layer  102 . For example, an opaque masking layer such as opaque masking layer  106  may be formed in inactive area IA on the upper (outermost) surface of display cover layer  102  and may be covered with an optional coating  108  (e.g., a polymer layer, an inorganic layer, etc.). 
     If desired, an additional layer of a polymer film or other film may be formed on the surface of display structures  100 . This layer of film may be used in forming an opaque masking layer in inactive area IA. In the example of  FIG. 11 , additional film  110  has been added to display structures  100  (e.g., the display structures of display  14  of  FIG. 7 ,  FIG. 8 , or  FIG. 9 ) and opaque masking layer  112  has been formed on the surface of additional film  110  in inactive area IA. In the example of  FIG. 12 , opaque masking layer  112  has been formed between additional film  110  and display structures  100 . Additional film  110  may be based on one or more layers of material such as a transparent polymer layer and may have materials, coatings, surface treatments, or other attributes to provide display  14  with desired features such as smudge resistance, scratch resistance, anti-reflection behavior, antistatic behavior, and other desired features. Opaque masking layer  112  may have the shape of a rectangular ring (as an example). 
       FIG. 13  is a cross-sectional side view of display  14  illustrating how an opaque masking layer such as opaque masking layer  114  may be formed between polarizer  46  and substrate  48  in a bottom emission display of the type shown in  FIG. 7 . Opaque masking layer  114  may be deposited and patterned on the upper surface of substrate  48  of display  14  of  FIG. 13  or may be deposited and patterned on the lower surface of polarizer  46  of display  14  of  FIG. 13 . 
       FIG. 14  is a cross-sectional side view of a bottom emission display such as bottom emission display  14  of  FIG. 7  in a configuration in which opaque masking layer  116  has been formed on the surface of substrate  48  facing organic light-emitting diode layer  50 . If desired, a planarization layer such as planarization layer  118  may be formed over opaque masking layer  116  in inactive area IA and over the rest of substrate  48  in active area AA. The organic light-emitting diode structures of organic light-emitting diode layer  50  may then be formed on planarization layer  118  (i.e., on the lower surface of planarization layer  118  in the orientation of  FIG. 14 ). Examples of planarization materials that may be used in forming planarization layer  118  include one or more layers of cyclobutane, one or more layers of spin-on glass, or one or more layers of polymers. Other types of planarization layers may be used in forming planarization layer  118 , if desired. 
       FIG. 15  is a cross-sectional side view of a top emission display of the type shown in  FIG. 8 . In the illustrative configuration of  FIG. 15 , opaque masking layer  120  has been formed between circular polarizer  78  and encapsulant layer  74  in inactive area IA. Opaque masking layer  120  may be formed on the top of encapsulant  74  (e.g., on top of a glass layer or other transparent member in layer  74 ) or may be formed on the bottom of circular polarizer  78 . If desired, the opaque masking layer may be formed on the top surface of circular polarizer  78 , as illustrated by dashed line  122 . 
       FIG. 16  is a cross-sectional side view of a top emission display of the type shown in  FIG. 9 . In the illustrative configuration of  FIG. 16 , opaque masking layer  124  has been formed between color filter layer  96  and encapsulant layer  74  in inactive area IA. Opaque masking layer  124  may be formed on the top of encapsulant  74  (e.g., on top of a glass layer or other transparent member in layer  74 ) or may be formed on the bottom of color filter layer  96 . If desired, the opaque masking layer may be formed on the top surface of color filter layer  96 , as illustrated by dashed line  126 . 
       FIG. 17  is a cross-sectional side view of an illustrative circular polarizer in display  14 . As shown in  FIG. 17 , circular polarizer  128  (e.g., circular polarizer  46  of  FIG. 7  or circular polarizer  78  of  FIG. 8 ) may be formed from multiple layers of material (i.e., polarizer  128  may be formed form multiple polarizer sublayers). Polarizer film  132  may be formed from a stretched polymer such as stretched polyvinyl alcohol (PVA) and may therefore sometimes be referred to as a PVA layer. Iodine may be placed on the stretched PVA film so that iodine molecules align with the stretched film and form the polarizer. Other types of polarizer films may be used if desired. 
     Polarizer film  132  may be sandwiched between supporting layers  130  and  134 . Polarizer support layers  130  and  134  may be formed from a material such as tri-acetyl cellulose (TAC) and may sometimes be referred to as TAC films. If desired, layers  130  and  134  may be formed from other polymers. The TAC films may help hold the PVA film in its stretched configuration and may protect the PVA film. Other films may be attached to polarizer film  132  if desired. 
     Polarizer  128  can be provided with a retarder layer such as retarder layer  136 . Retarder  136  may be, for example, a quarter-wave plate. To minimize the effects of chromatic dispersion, quarter-wave plate  136  may, if desired, be formed from two eighth-wave plates with counteracting chromatic dispersion characteristics (e.g., eighth-wave plates  136 B and  136 A joined along seam  150 ). 
     As shown in  FIG. 17 , opaque masking material can be formed in inactive area IA in locations such as location  138  (e.g., on top of the upper surface of a polarizer support layer such as TAC layer  130 ), in the location of opaque masking layer  140  between TAC layer  130  and PVA layer  132  (e.g., on the lower surface of TAC layer  130  or the upper surface of PVA layer  132 ), in the location of opaque masking layer  142  between PVA layer  132  and TAC layer  134 , (e.g., on the lower surface of PVA layer  132  or on the upper surface of TAC layer  134 ), in the location of opaque masking layer  144  between TAC layer  134  and retarder  136  (e.g., on the lower surface of TAC layer  134  or on the upper surface of retarder  136 ), in the location of opaque masking layer  146  (e.g., on the lower surface of eighth wave plate  136 A or the upper surface of eighth wave plate  136 B), or in the location of opaque masking layer  148  (e.g., on the lower surface of retarder  136  or on the upper surface of substrate  48  of  FIG. 7  or the upper surface of encapsulant layer  74  of  FIG. 8 ). 
     The foregoing is merely illustrative of the principles of this invention and various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention.

Metadata:
Filing Date: 20140211
Publication Date: 20160412
Grant Date: 20160412
Priority Date: 20130315
Inventors: DRZAIC PAUL S.
GARELLI ADAM T.
YIN VICTOR H.
MATHEW DINESH C.
Assignee: APPLE INC
CPC Classifications: [{"code": "H01L27/3244", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L51/5284", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01L51/5281", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/86", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K59/12", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K50/865", "inventive": true, "first": true, "tree": "[]"}, {"code": "H10K59/12", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K59/8791", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 51524539