PATENT DOCUMENT

Publication Number: US-9497529-B2
Application Number: US-201414183306-A
Country: US
Kind Code: B2

Title: Microphone port with foreign material ingress protection

Abstract:
An electronic device may be provided with a microphone in a microphone port. A shield may cover a microelectromechanical systems microphone device on a microphone substrate. An opening in the microphone substrate may form a sound port for the microphone. The microphone port may be formed by perforations in the microphone substrate or other layers such as a flexible printed circuit layer, a sheet metal layer, a layer of adhesive, a flexible polymer carrier layer in an adhesive tape, or an electronic device housing. The perforations may be sufficiently small to help resist the intrusions of foreign material such as liquid and dirt into the sound port of the microphone. Larger openings may be formed in other structures such as an electronic device housing. The larger openings may serve as sound passageways for the microphone port while being sufficiently large to resist clogging.

Claims:
What is claimed is: 
     
       1. Apparatus, comprising:
 an electronic device housing having opposing inner and outer surfaces; 
 a first plurality of openings each of which passes part way from the inner surface into the electronic device housing; 
 a second plurality of openings each of which has a larger diameter than the openings of the first plurality of openings and each of which passes part way from the outer surface into the electronic device housing, wherein the second plurality of openings joins with the first plurality of openings to form microphone port sound passageways through the electronic device housing; and 
 a microphone having a sound port in alignment with the first plurality of openings that receives sound through the microphone port sound passageways, wherein the first plurality of openings is interposed between the second plurality of openings and the sound port. 
 
     
     
       2. The apparatus defined in  claim 1  further comprising a flexible printed circuit to which the microphone is mounted, wherein the flexible printed circuit has an opening aligned with the sound port. 
     
     
       3. The apparatus defined in  claim 2  further comprising a layer of adhesive that attaches the flexible printed circuit to the inner surface of the electronic device housing, wherein the layer of adhesive has an opening aligned with the opening in the flexible printed circuit. 
     
     
       4. Apparatus, comprising:
 a microphone having a sound port; 
 a flexible printed circuit having an opening aligned with the sound port; and 
 adhesive tape attached to the flexible printed circuit, wherein the adhesive tape has a flexible polymer carrier layer with a plurality of perforations aligned with the opening in the flexible printed circuit, wherein the adhesive tape comprises an adhesive layer formed on a surface of the polymer carrier layer, and wherein the adhesive layer comprises an opening that is larger than each of the plurality of perforations in the flexible polymer layer. 
 
     
     
       5. The apparatus defined in  claim 4  wherein the adhesive layer attaches the flexible polymer carrier layer to the flexible printed circuit. 
     
     
       6. The apparatus defined in  claim 5  wherein the opening in the adhesive layer is aligned with the opening in the flexible printed circuit. 
     
     
       7. The apparatus defined in  claim 4  further comprising:
 an electronic device housing having an opening aligned with the opening in the flexible printed circuit, wherein the adhesive layer is a first adhesive layer that attaches the flexible polymer carrier layer to the flexible printed circuit, wherein the adhesive tape includes a second adhesive layer that attaches the flexible polymer carrier layer to the electronic device housing, wherein the opening in the first adhesive layer is aligned with the opening in the flexible printed circuit and wherein the second adhesive layer has an additional opening aligned with the opening in the electronic device housing.

Description:
BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with openings for audio input ports. 
     Electronic devices often include audio components such as speakers and microphones. Audio components are generally mounted within audio ports in device housings. For example, a microphone may be mounted in a microphone port located along the edge of a metal or plastic electronic device housing. 
     Microphones can be damaged by exposure to liquid or dirt. Accordingly, protective structures are often formed in a microphone ports. As an example, a microphone port may be provided with a layer of plastic mesh fabric. The mesh may have small openings that help prevent intrusion of liquid or dirt into the interior of the microphone port. The small openings in the mesh may be susceptible to clogging with skin oils or other materials, so a coarse screen or a housing, with larger openings may be placed over the mesh to help protect the mesh. Coarse screens are also sometimes incorporated into microphone ports to enhance the appearance of the microphone port. 
     Microphone ports with protective structures such as these may be complex and undesirably bulky. Also, the multitude of layers used with these structures can introduce potential leak paths to the interior of the device, providing coupling to internal device noise which is to be avoided. 
     It would therefore be desirable to be able to provide improve audio port structures such as improved microphone ports in electronic devices. 
     SUMMARY 
     An electronic device may be provided with a microphone port. A microphone may be mounted within the electronic device in alignment with the microphone port. The microphone port may be formed by sound passageways that allow sound to enter the electronic device and reach a sound port in the microphone. 
     The microphone may be formed from a microelectromechanical systems microphone device mounted on a microphone substrate. A shield may cover the microelectromechanical systems microphone device and an associated integrated circuit with microphone support circuitry. Solder or adhesive may be used in attaching the shield to the microphone substrate. An opening in the microphone substrate may form the sound port for the microphone. 
     The microphone port may be formed by perforations in the microphone substrate or perforations in other layers such as a flexible printed circuit layer to which the microphone substrate is attached, a planar member such as a sheet metal layer, a layer of adhesive, a flexible polymer carrier layer in an adhesive tape, or an electronic device housing. 
     The perforations may be sufficiently small to help resist the intrusion of foreign material such as liquid and dirt into the microphone port and therefore the sound port of the microphone. Larger openings that overlap the perforations may also be formed in structures associated with the microphone port. The larger openings may, for example, be formed as part of an electronic device housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device such as a laptop computer in accordance with an embodiment. 
         FIG. 2  is a perspective view of an illustrative electronic device such as a handheld electronic device in accordance with an embodiment. 
         FIG. 3  is a perspective view of an illustrative electronic device such as a tablet computer 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 in accordance with an embodiment. 
         FIG. 5  is a cross-sectional side view of a portion of an electronic device having a microphone port that includes perforations in a flexible printed circuit in accordance with an embodiment. 
         FIG. 6  is a cross-sectional side view of an illustrative microphone of the type that may be mounted in a microphone port In an electronic device in accordance with an embodiment. 
         FIG. 7  is a cross-sectional side view of a portion of an electronic device having a microphone port that includes perforations on a microphone substrate on which microphone structures such as a microelectromechanical systems microphone device and integrated circuit with microphone support circuitry have been, mounted in accordance with an embodiment. 
         FIG. 8  is a cross-sectional side view of a portion of an electronic device having a microphone port that includes overlapping small and large perforations in a device housing in accordance with an embodiment. 
         FIG. 9  is a cross-sectional side view of a portion of an electronic device having a microphone port formed using a planar member such as a sheet of metal with perforations in accordance with an embodiment. 
         FIG. 10  is a cross-sectional side view of a portion of an electronic device having a microphone port formed using a planar member such as a layer of perforated adhesive in accordance with an embodiment. 
         FIG. 11  is a cross-sectional side view of a portion of an electronic device having a microphone port formed using a perforated flexible polymer carrier film in a pressure sensitive adhesive tape in accordance with an embodiment. 
         FIG. 12  is a cross-sectional side view of an illustrative housing opening for a microphone port in accordance with an embodiment. 
         FIG. 13  is a cross-sectional side view of an illustrative series of overlapping fine and coarse housing openings for a microphone port in accordance with an embodiment. 
         FIG. 14  is a cross-sectional side view of an illustrative housing with openings for forming a microphone port in accordance with an embodiment. 
         FIG. 15  is a cross-sectional side view of an illustrative housing with an opening filled with a mesh layer for a microphone port in accordance with an embodiment. 
         FIGS. 16 and 17  are diagrams showing illustrative patterns that may be used when forming microphone port openings in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may be provided with audio components. Audio components in an electronic device may include speakers, tone generators, or other components that generate sound. Audio components may also include components that measure sound such as microphones. Audio ports may be provided in electronic device housings to accommodate audio components such as these. With one suitable arrangement, which is sometimes described herein as an example, an electronic device housing is provided with a microphone port for accommodating a microphone. The microphone port includes structures that help prevent intrusion of contaminants such as liquid and dirt particles. In general, any suitable type of component may be mounted in a port of this type (e.g., a speaker or other sound-generating audio component a light-generating component, or other device component). Configurations in which a device is provided with a microphone and microphone port are described as an example. In general, however, electronic devices may be provided with any suitable type of port that prevents intrusion of contaminants such as liquid and dirt particles. 
     Illustrative electronic devices of the types that may be provided with ports such as microphone ports 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 . Microphone port  32  may be formed on an edge of housing  12  or elsewhere in housing  12 . 
       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 device  10   12 . Display  14  may have an exterior layer that includes openings for components such as button  26  and speaker port  28 . Microphone port  32  may be formed along the lower edge of housing  12  as shown in  FIG. 2  or may be formed elsewhere in housing  12 . 
     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 . Microphone port  32  may be formed along one of the edges of housing  12  or elsewhere in housing  12 . 
       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 tabletop or desk. As shown in  FIG. 4 , microphone port  32  may be formed along one of the edges of housing  12  (as an example). 
     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. 
     A cross-sectional side view of a portion of electronic device  10  (e.g., a device such as devices  10  of  FIGS. 1, 2, 3 , or  4  or other suitable electronic device) is shown in  FIG. 5 . In the configuration of  FIG. 5 , microphone port  32  has been formed from opening  34  in housing  12  and from a group of openings  48  in a printed circuit such as flexible printed circuit  46 . 
     Microphone  36  may be mounted on flexible printed circuit  46  in alignment with openings  48  and opening  34 . By aligning microphone  36  with the openings of microphone port  32 , microphone  36  can receive sound through microphone port  32  during operation. 
     Microphone  36  may be a microelectromechanical systems (MEMS) microphone or other suitable type of microphone. Region  38  may serve as a sound port for microphone  36  (i.e., microphone  36  may receive sound through an opening in the substrate of the package for microphone  36  in region  38 ). As shown in  FIG. 5 , sound port (opening)  38  may be aligned with the openings of microphone port  32  such as openings  48  and opening  34  to ensure that sound from the exterior of device  10  can be satisfactorily received by microphone  36 . 
     Circuitry and other structures within microphone  36  are coupled to microphone terminals that are soldered to flexible printed circuit  46 . Solder connections may also help mechanically attach microphone  36  to flexible printed circuit  46 . As shown in the example of  FIG. 5 , microphone  36  may have contacts  40  that mate with corresponding contacts  44  on flexible printed circuit  46 . Solder  42  may be used for connecting contacts  40  to contacts  44 . If desired, a ring-shaped solder connection that runs around the periphery of microphone  36  may he used in connecting microphone  36  to flexible printed circuit  46 . 
     Flexible printed circuit  46  may contain one or more dielectric layers and one or more layers of patterned metal traces for forming contacts  42  and internal signal traces  54 . Flexible printed circuit  46  may be formed from a sheet of polyimide or a layer of other flexible polymer. 
     Adhesive  52  such as pressure sensitive adhesive may be used to attach flexible printed circuit  46  to a structure in device  10  such as inner surface  56  of electronic device housing (housing wall)  12 . Adhesive layer  52  may have an opening such as opening  50  that forms part of microphone port  32 . As shown in  FIG. 5 , opening  34  in housing  12 , opening  50  in adhesive layer  52 , and openings  48  in flexible printed circuit  46  may be aligned to form microphone port  32  and may be aligned with sound port  38  of microphone  36 , so that sound from the exterior of device  10  may reach sound port  38  through microphone port  32 . 
     Opening  34  may have a relatively large size (e.g., a diameter of 0.1 mm or more, 0.2 mm or more, 0.5 mm or more, 1 mm or more, 0.1-2 mm, 0.5-5 mm, etc). Opening  50  may have a size comparable to that of opening  34 . Openings  48  may have smaller diameters than openings such as openings  50  and  34 . For example, openings  48  may each have a diameter of less than 0.2 mm, less than 0.1 mm, less than 0.05 mm, less than 0.02 mm, less than 0.01 mm, less than 0.005 mm, 0.001-0.05 mm, 0.001-0.02 mm, or other suitable size. The use of relatively small diameters for openings  48  may help prevent intrusion of liquid, dirt, and other foreign material into sound opening  38 , thereby preventing microphone  36  from becoming blocked with contaminants that could prevent sound from passing through opening  38  to the interior of microphone  36 . Small openings such as openings  48  of  FIG. 5  are sometimes referred to as microperforations (“microperf”). Microperforations  48  may be circular, square, rectangular, oval, may have outlines with curved edges, straight edges, or a combination of curved and straight edges, or may have other suitable shapes (when viewed in vertical direction Z). 
     Very small openings such as some microperforations  48  may become clogged in the presence of finger oils or other environmental contaminants. By recessing microperforations  48  within opening  34  (i.e., at a depth D away from exterior housing surface  60 ), microperforations  48  are protected from contact with a user&#39;s fingers and are therefore less likely to become clogged than if microperforations  48  were formed on the outermost surface of device  10 . If desired, however, microperforations  48  may be located on the outermost surface of housing  12  and/or flexible printed circuit  46  may be located in a more exposed location. The configuration of  FIG. 5  is merely illustrative. 
       FIG. 6  is a cross-sectional side view of an illustrative microphone for device  10 . As shown in  FIG. 6 , microphone  36  may have a substrate such as microphone substrate  76 . Microphone substrate  76  may be formed from a dielectric material such as rigid printed circuit board material (as an example). Substrate  76  may include signal lines formed from patterned metal traces  72 . Sound opening  38  may be formed from an opening in substrate  76 . Microphone  36  may have a semiconductor die that forms microelectromechanical systems (MEMS) microphone device  66  and may have support circuitry such as application-specific integrated circuit die  64 . Wire bonds  74  and/or solder connections may be used to couple device  66 , integrated circuit  64  and/or other microphone circuitry to contacts  70 . Metal shield  62  may be coupled to metal traces such as contacts  70  using solder  68 . In this configuration, shield  62  covers integrated circuit  64  and microelectromechanical systems microphone device  66 . Traces  72  may electrically contacts  70  and microphone contacts  40 . Other configurations may be used for forming microphone  36  if desired. The example of  FIG. 6  is merely illustrative. 
     As shown in  FIG. 7 , perforations such as microperforations  48  for microphone port  32  may be formed directly in microphone substrate  76 , rather than in a separate printed circuit such as printed circuit  46  of  FIG. 5 . Adhesive such as pressure sensitive adhesive  52  may attach microphone substrate  76  and therefore microphone  36  to inner surface  56  of housing  12 . Microperforations  48  may be aligned with microelectromechanical systems microphone device  66  (i.e., the MEMS microphone component of microphone  36 ). This allows microperforations  48  to serve both as microphone sound port  38  for microphone  36  and as a structure that blocks dirt, liquid, and other foreign material so that this foreign material does not interfere with sound port  38 . Signals may be routed from microphone,  36  to a motherboard or other printed circuit in device  10  using a flexible printed circuit that is coupled to substrate  76 . For example, signals may be conveyed using flexible printed circuit  80  and connector  82  on substrate  76  or using integral flexible printed circuit tail  84 . Connector  82  may be, for example, a board-to-board connector. Flexible printed circuit tail  84  may be a length of flexible printed circuit material that extends out of rigid printed circuit board material that is used in forming substrate  76  (i.e., microphone substrate  76  may be formed from a “rigid flex” printed circuit). 
     If desired, microphone port  32  may be formed using microperforations in housing  12 . As shown in  FIG. 8 , for example, microphone port  32  may have a plurality of micro perforations  48  that are formed in inner surface  56  of housing  12 . Microperforations  48  may extend through housing  12  or may, as shown in  FIG. 8 , extend only partway through housing  12 . In the  FIG. 8  example, larger openings  88  (i.e., openings that have larger diameters than the diameters of microperforations  48  and that therefore each overlap multiple microperforations  48 ) may be formed on exterior surface  60 . Larger openings  88  penetrate part way into housing  12  from surface  60  of housing  12  to opposing surface  56  of housing  12 . Microperforations  48  extend part way from surface  56  into housing  12 . Openings  88  join up with openings  48  in the middle of housing  12 , thereby forming sound passageways for microphone port  32 . 
     The larger size of openings  88  (e.g., 0.1-0.2 mm, 0.05-0.3 mm, more than 0.1 mm, more than 0.2 mm, more than 0.3 mm, or other suitable size) help prevent openings  88  from becoming clogged in the even that a user&#39;s fingers rub across exterior surface  60  of housing  12  at microphone port  32 . The smaller size of openings  48  helps ensure that openings  48  will serve as a barrier to the intrusion of foreign material such as undesired liquid and dirt particles. 
     In the illustrative configuration of  FIG. 9 , microperforations  48  have been formed in planar member  90 . Microphone  36  may be mounted to flexible printed circuit  46  using solder  42  or other attachment mechanisms. Adhesive layer  52 - 1  may be used to attach flexible printed circuit  46  to member  90 . Adhesive layer  52 - 2  may be used to attach member  90  to inner surface  56  of housing  12 . Adhesive layers  52 - 1  and  52 - 2  may be formed from pressure sensitive adhesive or other adhesive. Openings in adhesive layers  52 - 1  and  52 - 2  may be aligned with the other openings of microphone port  32 . For example, adhesive layer  52 - 1  may have opening  50   1 , which is aligned with opening  86  of flexible printed circuit  46 . Adhesive layer  52 - 2  may have opening  50 - 2 , which is aligned with opening  86  of flexible printed circuit  46 . Opening  34  in housing  12  may be aligned with openings  86 ,  50 - 1 , and  50 - 2  and with microperforations  48  in member  90 . Member  90  may be formed from a sheet of material such as plastic or metal. For example, member  90  may be a layer of stainless steel or other sheet of metal and may serve as a stiffener for flexible printed circuit  46 . Microperforations  48  may allow sound to pass through microphone port  32  to sound opening  38  of microphone  36 , while serving as a barrier to the intrusion of foreign material such as liquid and dirt particles. The shape and layout of perforations  48  may be selected to provide microphone port  32  with a desired cosmetic appearance. 
       FIG. 10  is a cross-sectional side view of a portion of electronic device  10  in a configuration in which microphone port  32  has sound passageways formed from microperforations  48  in a layer of adhesive (e.g., a planar member formed from a layer of pressure sensitive adhesive or a layer of other adhesive material). As shown in  FIG. 10 , microphone  36  may be mounted to. flexible printed circuit  46  using solder  42  or other attachment mechanisms. Adhesive layer  52  may be used to attach flexible printed circuit  46  to the inner surface of housing  12 . Microperforations  48  may be formed in adhesive layer  52  in alignment with opening  86  in flexible printed circuit layer  46  and opening  34  in housing  12 . Microperforations  48  may allow sound to pass through adhesive layer  52  in microphone port  32  to sound opening  38  of microphone  36 , while serving as a barrier to the intrusion of foreign material such as liquid and dirt particles. 
     Adhesive tape may be used in attaching flexible printed circuit  46  to housing  12 , as shown in  FIG. 11 . With a configuration of the type shown in  FIG. 11 , flexible printed circuit  46  may be provided with an opening  86  that is aligned with sound port  38  of microphone  36 . Microphone  36  may be mounted to flexible printed circuit  46  using solder  42 . Adhesive tape  92  has a flexible polymer carrier layer such as carrier  94  sandwiched between upper adhesive layer  52 - 1  and lower adhesive layer  52 - 2 , respectively. Tape  92  may be used to attach flexible printed circuit  46  to the inner surface of electronic device housing  12  in device  10 . Adhesive layers  52 - 1  and  52 - 2  may be formed from pressure sensitive adhesive or other adhesive. Openings in adhesive layers  52 - 1  and  52 - 2  may be aligned with the other openings of microphone port  32 . For example, adhesive layer  52 - 1  may have an opening such as opening  50 - 1  that is aligned with opening  86  of flexible printed circuit  46 . Adhesive layer  52 - 2  may have an opening such as opening  50 - 2  that is aligned with opening  86  of flexible printed circuit  46 . Opening  34  in housing  12  may be aligned with openings  86 ,  50 - 1 , and  50 - 2  and with microperforations  48  in carrier  94 . Microperforations  48  in carrier  94  may allow sound to pass through carrier  94  in microphone port  32  to sound opening  38  of microphone  36 , while serving as a barrier to the intrusion of foreign material such as liquid and dirt particles. 
     If desired, openings such as openings  34  of  FIGS. 5, 7, 9, 10, and 11  may be provided with tapered sidewalls, as shown in  FIG. 12 . Sidewalls  95  may taper outwardly so that opening  34  is larger on outer housing surface  60  than on inner housing surface  56 , thereby enhancing the acoustic performance of microphone port  32 . 
       FIG. 13  is a cross-sectional side view of a portion of housing  12  in which a microphone port opening is formed from overlapping larger and smaller openings. The overlapping larger and smaller openings create sound passageways through housing  12  for microphone port  32 , as descried in connection with the illustrative example of  FIG. 8 . With the configuration of  FIG. 13 , microperforations  48  extend from inner surface  56  part way through housing  12 . Larger openings (i.e., perforations with larger diameters than perforations  48 ) such as openings  88  may extend from outer surface  60  part way through housing  12 . Openings  88  and microperforations  48  join to form sound passageways that allow sound to reach microphone  36 . The larger size of openings  88  prevents openings  88  from becoming clogged with oils or other materials. The smaller size of microperforations  48  allows microperforations to prevent the intrusion of foreign materials such as liquid and dirt into the interior of device  10 . If desired, openings such as openings  34  of  FIGS. 5, 7, 9, 10, and 11  may be implemented using a configuration of the type shown in  FIG. 13 . When this type of arrangement is used, microperforations  48  on other layers in microphone port  32  (e.g., on flexible printed circuit  46 , metal layer  90 , adhesive tape carrier  94 , etc., can be omitted or may be formed using enlarged openings). 
     In the illustrative configuration of  FIG. 14 , port  32  has a pattern of housing openings  88  (e.g., relatively larger openings that have diameters of 0.1-0.2 mm, 0.05-0.3 mm, more than 0.1 mm, more than 0.2 mm, more than 0.3 mm, or other suitable size). This type of arrangement may be used to provide an outer set of sound passageways for microphone port  32  in place of openings such as openings  34  of  FIGS. 5, 7, 9, 10, and 11 . 
       FIG. 15  shows how an opening such as openings  34  of  FIGS. 5, 7, 9, 10, and 11  may be provided with a mesh layer such as mesh layer  96 . Mesh layer  96  may have relatively small openings for preventing the intrusion of foreign material such as liquid and dirt or may have larger openings. For example, mesh layer  96  may have small openings such as openings that have a diameter of less than 0.2 mm, less than 0.1 mm, less than 0.05 mm, less than 0.02 mm, less than 0.01 mm, less than 0.005 mm, 0.001-0.05 mm, 0.001-0.02 mm, or other suitable size and/or may have larger openings such as openings of 0.1-0.2 mm, 0.05-0.3 mm, more than 0.1 mm, more than 0.2 mm, more than 0.3 mm, or other suitable size. Mesh  96  may be formed from interwoven fibers such as interwoven, plastic and/or metal fibers. 
     The openings of port  32  such as microperforations  48  and/or openings  88  may be formed in an array or other suitable pattern (see, e.g., the rectangular array of openings  98  of  FIG. 16  and/or the circular pattern of openings  98  of  FIG. 17 ). Other patterns of openings may be used if desired. 
     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: 20140218
Publication Date: 20161115
Grant Date: 20161115
Priority Date: 20140218
Inventors: JEZIOREK PETER N.
CROSBY JUSTIN D.
NGUYEN TRANG THI-THANH
GOLDBERG MICHELLE R.
Assignee: APPLE INC
CPC Classifications: [{"code": "H04R2499/11", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/086", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R19/005", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R19/04", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R19/005", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R19/04", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/086", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R2499/11", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 53799315