PATENT DOCUMENT

Publication Number: US-10976834-B1
Application Number: US-201916595930-A
Country: US
Kind Code: B1

Title: Light integrated sensing membrane

Abstract:
Embodiments are directed to a sensing membrane that is coupled with electrical terminals of a key switch and a light source. This may allow the membrane to be both configured to transmit a signal in response to actuation of keyboard key cap and illuminate an illuminable symbol of key cap. In one aspect, the membrane includes a set of deformable layers separated by a spacer layer. Terminals of the key switch are connected to distinct ones of the set of deformable layers and positioned within a cavity defined by the spacer layer. A light assembly may be positioned along and configured to move with one of the set of deformable layers. Depression of a key cap toward the set of deformable layers causes the set of terminals to move and initiate a switch event.

Claims:
What is claimed is: 
     
       1. A keyboard, comprising: a key cap;
 a tactile dome below the key cap; 
 a first deformable layer positioned below the tactile dome; 
 a second deformable layer separated from the first deformable layer by a cavity; an electrical terminal of a key switch positioned on the first deformable layer; and a light assembly having a light source fully encapsulated between the second deformable layer and a protective coating and at least partially disposed below an upper surface of a feature plate; 
 wherein the tactile dome is configured to collapse and electrically couple the electrical terminal with an element of the keyboard. 
 
     
     
       2. The keyboard of  claim 1 , wherein:
 the electrical terminal is a first electrical terminal of the key switch; 
 the element of the keyboard is a second electrical terminal of the key switch positioned on the second deformable layer; 
 the key cap defines an illuminable symbol; and 
 the light source illuminates the illuminable symbol by emitting light through one or more of the set of deformable layers. 
 
     
     
       3. The keyboard of  claim 2 , wherein:
 the keyboard further comprises a spacer layer positioned between the first deformable layer and the second deformable layer and that defines the cavity; 
 the first electrical terminal is positioned within the cavity; 
 the second electrical terminal is positioned within the cavity; and 
 the first electrical terminal and the second electrical terminal are configured to physically contact one another upon collapse of the tactile dome, thereby triggering a switch event. 
 
     
     
       4. The keyboard of  claim 1 , wherein:
 the key cap defines an illuminable symbol; 
 the tactile dome comprises a contact feature configured to move the electrical terminal when the tactile dome collapses; and 
 the contact feature is translucent and configured to direct light from the light source toward the illuminable symbol. 
 
     
     
       5. The keyboard of  claim 1 , wherein the first deformable layer defines a first surface and a second surface opposite the first surface, electrical traces are positioned on the first surface, and the electrical terminal is positioned on the second surface. 
     
     
       6. The keyboard of  claim 1 , wherein the light source is disposed at least partially below an upper surface of the feature plate disposed below the tactile dome. 
     
     
       7. The keyboard of  claim 1 , wherein the protective coating defines a light guide optically coupled with the light source and having at least one light extraction feature configured to direct light toward the key cap. 
     
     
       8. A keyboard, comprising: a key cap;
 a tactile dome below the key cap; 
 a first deformable layer positioned below the tactile dome; a key switch positioned on the first deformable layer and having an electrical terminal; 
 a second deformable layer separated from the first deformable layer by a cavity; 
 a feature plate disposed below the tactile dome; and 
 a light assembly having a light source, the light source being at least partially disposed within a relief cavity of the feature plate, the light assembly comprising a light extraction feature configured to propagate light toward the key cap; 
 wherein the light extraction feature comprises at least one of a textured surface, a lens, an aperture, or a translucent region; and 
 the light source is fully encapsulated between the second deformable layer and a protective coating. 
 
     
     
       9. The keyboard of  claim 8 , wherein the light source is coupled with electrical traces connected to the one of the set of the deformable layers. 
     
     
       10. The keyboard of  claim 9 , wherein the first deformable layer is configured to deform into the cavity in response to depression of the key cap, thereby causing the set of electrical terminals to initiate the switch event. 
     
     
       11. The keyboard of  claim 9 , wherein:
 a spacer layer defines the cavity; and 
 the relief is at least partially aligned with the cavity. 
 
     
     
       12. The keyboard of  claim 8 , wherein:
 the key cap includes an illuminable symbol; and 
 the light assembly is configured to propagate light toward the illuminable symbol during depression of the key cap. 
 
     
     
       13. The keyboard of  claim 12 , wherein the light assembly is configured to illuminate the illuminable symbol by propagating light along an optical path defined at least partially through one or more of the set of deformable layers or the spacer layer. 
     
     
       14. A keyboard, comprising: a key cap;
 a tactile dome below the key cap; a deformable layer positioned below the tactile dome; a key switch positioned on the deformable layer; 
 a plate disposed below deformable layer, a cavity formed in the plate below the tactile dome; and 
 a light assembly having a light source, the light source being at least partially disposed below an upper surface of the plate, wherein the light source is fully encapsulated between the deformable layer and a protective coating. 
 
     
     
       15. The electronic device of  claim 14 , wherein, the tactile dome defines a base positioned on the deformable layer, and the base is a translucent portion of the tactile dome configured to receive light from the light source. 
     
     
       16. The electronic device of  claim 15 , wherein an electrical terminal of the key switch is positioned within the cavity. 
     
     
       17. The electronic device of  claim 14 , wherein the light source comprises micro light emitting diodes. 
     
     
       18. The electronic device of  claim 14 , wherein, the electronic device further comprises an optical sensor coupled with the electrical terminal and wherein the optical sensor is configured to detect buckling of the tactile dome using reflected light.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     The present application is a continuation of U.S. patent application Ser. No. 15/839,548, filed Dec. 12, 2017, and titled “Light Integrated Sensing Membrane,” which claims the benefit of U.S. Provisional Patent Application No. 62/516,608, filed Jun. 7, 2017 and titled “Light Integrated Sensing Membrane,” the disclosures of which are hereby incorporated herein by reference in their entireties. 
    
    
     FIELD 
     The described embodiments relate generally to input devices for computing systems. More particularly, the present embodiments relate to structures that facilitate illumination of a keyboard. 
     BACKGROUND 
     In computing systems, a keyboard may be employed to receive input from a user. Many traditional keyboards may suffer from significant drawbacks that may affect the visibility of keyboard keys in a dimly-lit environment. In many cases, traditional keyboards include various mechanical and electrical components that may impede illumination of the keyboard. 
     SUMMARY 
     Embodiments of the present invention are directed to a light integrated sensing membrane. The light integrated sensing membrane may include a light source and electrical terminals of a key switch, each coupled to a common deformable layer. 
     One embodiment may take the form of a keyboard, comprising: a key cap; a tactile dome below the key cap; a deformable layer positioned below the tactile dome; an electrical terminal of a key switch positioned on the deformable layer; and a light assembly having a light source; electrical traces positioned on the deformable layer, coupled to the light source, and configured to deform with the deformable layer; wherein: the tactile dome is configured to collapse and electrically couple the electrical terminal with another element of the keyboard. 
     Another embodiment takes the form of a keyboard, comprising: a key cap; a set of deformable layers positioned below the key cap; a spacer layer separating the set of deformable layers; a set of electrical terminals, each of the set of electrical terminals connected to a distinct one of the set of deformable layers; and a light assembly positioned on, and configured to move with, one of the set of deformable layers, wherein: the key cap is configured to depress; and the set of electrical terminals is configured to move and initiate a switch event in response to depression of the key cap. 
     Still another embodiment takes the form of an electronic device, comprising: a deformable layer; a spacer layer adjacent the deformable layer and defining a cavity; a tactile dome positioned above both the deformable layer and the spacer layer; an electrical terminal connected to the deformable layer and operable to initiate an electrical response in response to buckling of the tactile dome; and a light assembly having a light source at least partially positioned within the deformable layer or the spacer layer, wherein: at least one of the deformable layer or the spacer layer defines a light guide configured to redirect light from the light source to an illuminable symbol positioned above the tactile dome; and the deformable layer is configured to deform into the cavity. 
     In addition to the sample aspects and embodiments described above, further aspects and embodiment will become apparent by reference to the drawings and by study of the following description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like elements. 
         FIG. 1  depicts a sample electronic device; 
         FIG. 2  depicts an exploded view of the key assembly of  FIG. 1 ; 
         FIG. 3A  depicts a cross-sectional view of a sample light integrated sensing membrane in an unactuated configuration, taken along line A-A of  FIG. 1 ; 
         FIG. 3B  depicts an embodiment of the light integrated sensing membrane of  FIG. 3A ; 
         FIG. 3C  depicts another embodiment of the light integrated sensing membrane of  FIG. 3A ; 
         FIG. 3D  depicts a top view of the electrical trace layer of the light integrated sensing membrane of  FIG. 3A ; 
         FIG. 3E  depicts a top view of the terminals of the light integrated sensing membrane of  FIG. 3A ; 
         FIG. 3F  depicts a cross-sectional view of the sample light integrated sensing membrane of  FIG. 3A  in an actuated configuration, taken along line A-A of  FIG. 1 ; 
         FIG. 4A  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, taken along line A-A of  FIG. 1 ; 
         FIG. 4B  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, taken along line A-A of  FIG. 1 ; 
         FIG. 4C  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, taken along line A-A of  FIG. 1 ; 
         FIG. 4D  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, taken along line A-A of  FIG. 1 ; 
         FIG. 4E  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, taken along line A-A of  FIG. 1 ; 
         FIG. 4F  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, taken along line A-A of  FIG. 1 ; 
         FIG. 4G  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, take along line A-A of  FIG. 1 ; 
         FIG. 4H  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, take along line A-A of  FIG. 1 ; and 
         FIG. 4I  depicts a cross-sectional view of another embodiment of a light integrated sensing membrane, taken along line A-A of  FIG. 1 . 
     
    
    
     The use of cross-hatching or shading in the accompanying figures is generally provided to clarify the boundaries between adjacent elements and also to facilitate legibility of the figures. Accordingly, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, element proportions, element dimensions, commonalities of similarly illustrated elements, or any other characteristic, attribute, or property for any element illustrated in the accompanying figures. 
     Additionally, it should be understood that the proportions and dimensions (either relative or absolute) of the various features and elements (and collections and groupings thereof) and the boundaries, separations, and positional relationships presented therebetween, are provided in the accompanying figures merely to facilitate an understanding of the various embodiments described herein and, accordingly, may not necessarily be presented or illustrated to scale, and are not intended to indicate any preference or requirement for an illustrated embodiment to the exclusion of embodiments described with reference thereto. 
     DETAILED DESCRIPTION 
     The description that follows includes sample systems, methods, and apparatuses that embody various elements of the present disclosure. However, it should be understood that the described disclosure may be practiced in a variety of forms in addition to those described herein. 
     The present disclosure describes systems, devices, and techniques related to a key assembly or other input mechanism for an input device, such as a keyboard. More particularly, the disclosure describes various illumination structures that may illuminate one or more key caps of a keyboard (or input surfaces of another input mechanism). An illumination structure may include a light integrated sensing membrane, or other translucent or light-transmissible structure or portion of the key assembly that includes electrical terminals of a key switch. A light source, such as a micro light emitting diode (mLED), may be positioned on, within, or partially surrounded by, one or more translucent and deformable layers of the membrane that may be coupled with the mLED and include electrical terminals of a key switch (e.g., the electrical terminals of the key switch may be positioned on, or in, the deformable layers). This may allow the light integrated sensing membrane to be configured to both transmit a signal in response to actuation of the keyboard key (via the electrical traces of the key switch) and illuminate an illuminable symbol of the key cap using a common or integrally formed deformable layer, as described herein. For example, a tactile dome positioned below the key cap and above the light integrated sensing membrane may collapse in response to an input and cause an electrical connection between the electrical terminals, thereby initiating a switch event. The electrical terminals may transmit this signal to a processing unit or other element of an electronic device, thereby registering the input as an input to the electronic device. 
     To facilitate the foregoing, the light source, such as the mLED, may be connected to, and/or partially surrounded by, one or more of the translucent deformable layers of the light integrated sensing membrane. Further, one or more of the translucent deformable layers may define or include signal-transmitting or initiating electrical terminals positioned thereon, or these terminals may be positioned on a surface of the layer. The electrical terminals may initiate an electrical response when connected that may trigger a switch event. By integrating the light source with the deformable layers as described herein, the overall size and/or thickness of the stack-up for the key assembly, or other input mechanism, may be reduced. Further, this may allow a surface area of the light integrated sensing membrane to be increased, which may enhance the ability to route switch circuitry (such as a key switch) and/or other electrical components in or over the light integrated sensing membrane. 
     The light integrated sensing membrane may include a light assembly having a light source coupled with electrical traces positioned on a deformable layer. As described herein, the deformable layer may also be used to trigger a switch event in response to a force input. In this regard, rather than provide a separate carrier or substrate for the light assembly, a deformable layer of the light integrated sensing membrane may be used to secure the light assembly within the key assembly. The light assembly may also include an optical layer, such as a phosphor layer, and/or a protective coating that may partially or fully encapsulate the light source or other component of the deformable layer. In one embodiment, the optical layer may be a phosphor layer and/or other light transmissible layer that may help control an optical characteristic of light emitted from the light source, such as a color, brightness, sharpness, and/or direction of the emitted light. The protective coating may be a translucent layer that is positioned over the light source and/or optical layer and configured to form a protective barrier between the light source and an environment of the key assembly. The protective layer may, in some cases, define a light guide coupled with light extraction features configured to expel light toward the key cap. 
     The light assembly may be coupled with one or two deformable layers of the light integrated sensing membrane. Broadly, the light integrated sensing membrane may include two (or more) such deformable layers that are configured to move toward one another in response to a force input received at the key cap, insofar as the deformable layers are positioned below the tactile dome, which is in turn positioned below the key cap. Thus, an input force on the key cap causes the key cap to translate, thereby buckling the tactile dome positioned below the key cap, and in turn moving at least one the deformable layers positioned below the tactile dome closer another deformable layer. 
     The two deformable layers may each support, be coupled with, or integrate electrical terminals or another element of a key switch and may be separated by a spacer layer separating the deformable layers and thus defining a cavity between the deformable layers. Electrical terminals of the key switch may be positioned on distinct ones of the first and second deformable layers and within the cavity. The first deformable layer may collapse, deform, or extend into the cavity and toward the second deformable layer under force, such that the electrical terminals of the key switch electrically couple to one another and trigger a corresponding switch event. For example, a tactile dome positioned below the key cap and above both of the deformable layers (e.g., such that the deformable layers are positioned below the tactile dome and the key cap) may be configured to collapse or buckle in response to an applied force from the key cap. The buckling of the tactile dome may cause a contact feature positioned on an underside of the tactile dome to contact and press into the first deformable layer positioned below the tactile dome. This may electrically couple an electrical terminal on the first deformable layer with another element, such as a second terminal, an electrical trace, an electrode, or the like. Such electrical coupling may initiate or terminate a signal, for example. 
     The light assembly, including the mLED, may be positioned along and/or within or partially within the first or second deformable layers in any appropriate configuration to illuminate a tactile dome and associated key or key cap positioned above the light integrated sensing membrane and tactile dome. In one embodiment, the light assembly may be positioned along or on the first deformable layer that includes, or is coupled with, at least a first of the electrical terminals of the key switch. The light assembly may be a top firing mLED positioned along a top surface of the first deformable layer and below the tactile dome, insofar as the deformable layer is positioned below the tactile dome. The top firing mLED may propagate light toward the tactile dome and cause illumination of the key cap positioned above the tactile dome. In this regard, the tactile dome may be a translucent or light transmissible structure (or have one or more translucent portions) that may allow light to pass therethrough. In some embodiments the light assembly may be arranged in various other configurations on or along the first deformable layer, including having a micro LED (mLED), or other suitable LED, positioned on or below a bottom surface of the first deformable layer. Additionally or alternatively, the light assembly may include a mLED within a recess or pocket or encapsulated by the first deformable layer. This may allow the first deformable layer to partially or fully surround the mLED or other light source, which may aid in using the first deformable layer as a light guide and help reduce a z-profile of the stack-up. 
     In another embodiment, the light assembly may be positioned along and/or partially or fully within the second deformable layer. A second of the electrical terminals of the key switch may be positioned on the second deformable layer. The light assembly may include a reverse firing mLED positioned on a bottom surface of the second deformable layer. In this regard, the light assembly and associated mLED may extend below the light integrated sensing membrane. As one example, the light source may extend below the light integrated sensing membrane and at least partially into a relief defined by a feature plate positioned below the light integrated sensing membrane. Generally, the relief may allow the light integrated sensing membrane to bend or bow into a region of the key assembly defined by the feature plate in response to a key press, which may help deliver a desired tactile response to a key cap of the key assembly. The relief may also surround at least some of the light assembly (e.g., the light source) to help improve the z-profile of the key assembly. In other embodiments, the light assembly may be positioned along a top surface of the second deformable layer, for example, such that the mLED of the light assembly is positioned with the cavity of the light integrated sensing membrane substantially between the electrical contacts that define the key switch. Additionally or alternatively, the light assembly may be positioned within a recess or pocket of the second deformable layer, which may allow the second deformable layer to be used as a light guide and may help improve the z-profile of the stack-up. 
     The light assembly may be configured to bend or deform with the deformable layers of the light integrated sensing membrane during actuation of the key assembly. For example, the light source, optical layer, protective coating, and/or electrical traces of the light assembly may be at least partially pliable or bendable in response to movements or bending of one or both of the deformable layers of the light integrated sensing membrane. In this regard, the mLED or other light source may be pressed or translated downward within the key assembly in response to a collapsing or buckling of the tactile dome caused by a depression of a key cap positioned above the tactile dome. This may allow the light source (with associated electrical traces) and the electrical traces of the key switch to be positioned on the same or common deformable layer, thereby potentially reducing or eliminating redundant components that may be used or otherwise required when a light source and a sensing membrane are isolated or separated components of a keyboard. 
     The light assembly may also be configured to direct or couple light directly into the tactile dome, which is positioned below a key cap. This may allow the tactile dome to be used as a light pipe or light conduit to propagate light between the light source and the key cap positioned above the tactile dome. In one configuration, the light assembly may include a mLED positioned directly below a contact feature or nub on the tactile dome. When the tactile dome is depressed, the contact feature may contact and partially conform or surround the mLED. As such, the contact feature and, more generally, a body of the tactile dome may function as a light guide that receives light from the light source and propagates the received light toward a key cap positioned along a top surface of the tactile dome. 
     In other cases, the light source may be positioned along a periphery of the tactile dome, for example, and extend partially or fully into a base of the tactile dome. For example, the tactile dome may include a recess or compartment along a periphery of the tactile dome that may be configured to receive the mLED or other light source of the light assembly with or about the base of the tactile dome. In some cases, the tactile dome may include reflective components or surfaces, including textured or treated surfaces, that may help channel light through the tactile dome and along the dome walls such that the light is propagated toward the illuminable symbol of the key cap. A “symbol,” as used herein, is a graphic, logo, text, letter, glyph, or other marking that conveys information. An “illuminable symbol” is a symbol that can be illuminated by a light source incorporated into an embodiment; typically, but not necessarily, the illuminable symbol is illuminated through an input surface such as a key cap, trackpad surface, or the like. 
     It will be appreciated that the mLED, or any other light sources described herein, may be positioned in any appropriate manner within the light integrated sensing membrane, including being positioned along or within one of the deformable layers positioned below the tactile dome and separated or spaced apart from the tactile dome. The mLED may be oriented and configured in a variety of manners to produce a desired optical effect, including being a top, rear, and/or side firing mLED. Further, the light source is not limited to a single mLED being positioned along a first and second deformable layer. Rather, the mLED may be one or a set or array of mLEDs positioned throughout the light integrated sensing membrane. In some cases, this may allow each key cap of a keyboard to be associated with a mLED of the array of mLEDs. Additionally or alternatively, each key cap, or a subset of key caps, of the keyboard may have multiple associated mLEDs of the array of mLEDs, as may be appropriate for a given configuration. 
     Reference will now be made to the accompanying drawings, which assist in illustrating various features of the present disclosure. The following description is presented for purposes of illustration and description. Furthermore, the description is not intended to limit the inventive aspects to the forms disclosed herein. Consequently, variations and modifications commensurate with the following teachings, and skill and knowledge of the relevant art, are within the scope of the present inventive aspects. 
       FIG. 1  depicts an electronic device  104  having a key assembly  108 , although other input mechanisms may incorporate the embodiments discussed herein. The key assembly  108  may be one of a set of key assemblies that collectively form a keyboard or other input structure of the electronic device  104 . The key assembly  108  may include a “stack-up” of components that cooperate to initiate an input signal in response to a force input. The key assembly  108  may enable substantially low-travel of an input surface (key cap) with a desired tactile response. The key assembly  108  may include a light integrated sensing membrane (not shown in  FIG. 1 ), such as the light integrated sensing membrane discussed above and described in greater detail below. As described herein, the light integrated sensing membrane may include a deformable and light transmissible layer that includes both electrical terminals of a key (or other contact) switch and electrical traces of a light assembly. The electrical traces may be positioned on, and deform with, the deformable layer. 
     In a non-limiting example, as shown in  FIG. 1 , the electronic device  104  may be a laptop computer. However, it is understood that electronic device  104  may be any suitable device that operates with the key assembly  108  (or any other suitable device or input mechanism configured to receive a touch and/or force input from a user). Some example electronic devices may include data-entry devices, word-processing devices, desktop computers, notebook computers (as shown in  FIG. 1 ), smart phones, tablets, portable media players, or the like. Other examples of electronic devices may include health monitoring devices (including pedometers, heart rate monitors, or the like), and other electronic devices, including digital cameras, printers, scanners, security systems or devices, electronics for automobiles, among other electronic devices. Suitable input mechanisms may include trackpads, mice, joystick buttons, and so on. 
     For purposes of illustration,  FIG. 1  depicts the electronic device  104  as including the key assembly  108 , an enclosure  112 , a display  116 , and one or more input/output members  119 . It should be noted that the electronic device  104  may also include various other components, such as one or more ports (e.g., a charging port, a data transfer port, or the like), communications elements, additional input/output members (including buttons), and so on. As such, the discussion of any computing device, such the electronic device  104 , is meant as illustrative only. 
     In a non-limiting example, the key assembly  108  may include a key cap  110 . The key cap  110  may have an illuminable portion or symbol at which light from a light source (within the enclosure  112 ) may visually emphasize a location, size, and/or functionality of the key cap  110 . The key cap  110  may be substantially surrounded by, and at least partially protrude from, the enclosure  112 . For example, the key cap  110  may be positioned within or partially within one of an array of openings defined in the enclosure  112 . The key cap  110  may be configured to receive a force input. The force input may depress the key cap  110  and trigger one or more input signals that may control the electronic device  104 . As depicted, the key assembly  108 , and associated keyboard, may be positioned within the electronic device  104  (e.g., within or partially within the enclosure  112 ). In other embodiments, the key assembly  108  may be a distinct, standalone component communicatively coupled with the electronic device  104  via a wireless or hardwired connection. 
       FIG. 2  depicts an illustrative exploded view of an embodiment of the key assembly  108  shown in  FIG. 1 . As described above, the key assembly  108  may be formed from a stack-up of layered components. Each layer and/or component of the stack-up of the key assembly  108  may provide different functionality and/or operations for the electronic device  104 , as discussed herein. Although a key assembly  108  is shown as a single key assembly stack-up, it is understood that substantially all key assemblies (or a subset of key assemblies) of the electronic device  104  may be formed from similar components and/or layers in a similar configuration and/or function in a substantially similar manner as the single key assembly stack-up shown in  FIG. 2 . For purposes of illustration,  FIG. 2  depicts the key assembly  108  as including a key cap  110 , an illuminable symbol  111 , a collar  114 , a key opening  115 , a butterfly mechanism  120 , wings  122   a ,  122   b , cavity  123 , hinge  124 , switch housing  128 , switch opening  130 , tactile dome  132 , light integrated sensing membrane  136 , series of membrane openings  138 , feature plate  142 , series of feature plate openings  146 , engagement feature  144 , and relief  148 . The light integrated sensing membrane  136  may include a light source (not shown in  FIG. 2A ) that may be used to direct light through the key assembly  108  and toward the illuminable symbol  111 . It should be noted that the key assembly  108  may also include various other components and/or different combinations of components. As such, the discussion of any key assembly  108 , such as the key assembly  108 , is meant as illustrative only. 
       FIGS. 3A-3F  depict the key assembly  108  described with respect to  FIGS. 1 and 2 . In particular,  FIGS. 3A-3F  depict various elements of the key assembly  108  that may be used to trigger a switch event and provide light to an illuminable symbol of a key cap positioned above the light integrated sensing membrane  136 . For the sake of clarity, some elements of the key assembly  108  associated with the light integrated sensing membrane  136  have been omitted in  FIGS. 3A-3F . 
     With reference to  FIG. 3A , a cross-sectional view of the key assembly  108  is shown taken along line A-A of  FIG. 1 . As described above, the key assembly  108  may include a tactile dome  132  positioned below the key cap  110  and above the light integrated sensing membrane  136 . In certain embodiments, the tactile dome  132  may have a base  135  positioned on a deformable region of the light integrated sensing membrane  136 . The tactile dome  132  may be configured to collapse or buckle in response to an actuation (depression) of the key cap  110  positioned above the tactile dome  132 , thereby producing a tactile effect at the key cap  110 . This may cause a contact feature  134  of the tactile dome to advance toward the deformable region and cause the light integrated sensing membrane  136  to trigger a switch event, as described herein. The light integrated sensing membrane  136  may be positioned on the feature plate  142 . The feature plate  142  may be a structural component of the key assembly  108  that is used to secure one or more components with the key assembly  108 , including the light integrated sensing membrane  136 , the switch housing  128 , and/or the butterfly mechanism  120  (not shown in  FIG. 3A ). In the embodiment of  FIG. 3A , the light integrated sensing membrane  136  is shown in an unactuated configuration. 
     As shown in  FIG. 3A , the light integrated sensing membrane  136  may include first and second deformable layers  150 ,  151 . The first and second deformable layers  150 ,  151  may be positioned below the tactile dome  132 . The first and second deformable layers  150 ,  151  may be a set of deformable layers that are separated within the light integrated sensing membrane  136  by a spacer layer  152 . The spacer layer  152  separate the first and second deformable layers  150 ,  151  and thus define a cavity  154  between the deformable layers. Each of the first and second deformable layers  150 ,  151  may have a first surface and a second surface. The first and second deformable layers  150 ,  151  may be constructed from any appropriate material including polyethylene terephthalate (PET), silicon, or the like; however, other materials may also be used, such as various plastics, synthetics and so on. 
     The first and second deformable layers  150 ,  151  may be coupled with electrical terminals or another element of a key switch positioned within the cavity  154  (e.g., on opposing sides or top and bottom regions of the cavity  154 , respectively). For example, the first deformable layer  150  may have, or be coupled with, a first electrical terminal  156  and the second deformable layer  151  may have, or be coupled with, a second electrical terminal  157 . The first and second electrical terminals  156 ,  157  may be a set of electrical terminals of a contact-based key switch that may complete an electrical circuit or switch when the first and second electrical terminals  156 ,  157  contact one another. It will be appreciated, however, that in other cases the first and second electrical terminals  156 ,  157  may be capacitive elements that cooperate to define a capacitive-based force sensor and/or other appropriate sensing structure for detecting movement of the key cap  110 . The electrical terminals, or any other electrical circuits described herein, may be formed from various appropriate electrically conductive material, including silver or silver alloy, copper, or the like; however, other materials or combinations of materials may also be used, including conductive epoxy, low temperature solder, and copper and/or alloy formed over or with a flexible printed circuit, among other materials and combinations of the materials. 
     As shown and described in greater detail with respect to  FIG. 3D , when the tactile dome  132  collapses or buckles, a volume of the cavity  154  may be reduced through motion of the first and second deformable layers  150 ,  151  (e.g., the deformable layers may deform or collapse into the cavity). This may cause the first and second electrical contacts  156 ,  157  to physically contact one another and trigger a switch event (e.g., by initiating an electrical response corresponding to the depression of the key cap  110 ). In this regard, the tactile dome  132  may be an electrically insulating structure. However, in other configurations, the tactile dome  132  may include an electrically conductive puck or other structure that may be used to complete a switch defined on and/or in the light integrated sensing membrane  136 , including being substantially formed from an electrically conductive material. 
     The light integrated sensing membrane  136  may include a light assembly, such as the light assemblies discussed above and described in greater detail below. As shown in  FIG. 3A , the light integrated sensing membrane  136  may include a light assembly  160 . The light assembly  160  may be positioned along a top surface of the first deformable layer  150  and used to illuminate an illuminable symbol of a key cap positioned above the light integrated sensing membrane  136  (e.g., illuminable symbol  111  and key cap  110  of  FIG. 2 ). In this regard, the light assembly  160  may be configured to emit light into the key assembly  108  and optionally through at least a portion of the tactile dome  132  (or other translucent portion or layer of the key assembly  108 ) and illuminate the illuminable symbol  111  of the key cap  110  above the tactile dome. 
     To facilitate the foregoing, the light assembly  160  may include a light source  162 . The light source  162  may be a micro light emitting diode (mLED), which may use or be microscopic light emitting diode elements that cooperate to form a light source. In other cases, other light sources may be implemented according to the embodiment described herein, including various combinations of a light emitting diode (LED), light guide, liquid crystal display (LCD), organic light emitting diode (OLED), fluorescent light, and/or other light emitting elements that propagate light through the key assembly  108  and toward the illuminable symbol  111 . In the embodiment of  FIG. 3A , the light source  162  may be a top firing mLED that directs light through or partially through the tactile dome  132  positioned below the key cap  110  and toward an illuminable symbol  111  of the key cap  110 ; however, other configurations and arrangements are described herein, including mLEDs that are side and/or rear firing mLEDs. For example, as shown in  FIG. 3A , the light source  162  may direct light substantially along light path L 1 . It will be appreciated that light path L 1  (or any light path described herein) may be depicted for purposes of illustration only. Rather than suggest that light emitted from the light assembly  160  travels exclusively along a particular light path, the illustrated light path L 1  is depicted to be a representation of diffuse light that propagates within the key assembly  108 . 
     The light source  162  may be partially or fully encapsulated by an optical layer  163 . The optical layer  163  may be a phosphor layer and/or other light transmissible layer that may form a protective barrier around the light source  162 . The optical layer  163  may also help control an optical characteristic of light emitted from the light source  162 , such as a color, brightness, sharpness, and/or direction of the emitted light. The light assembly  160  may also include protective coating  166  that may form a protective barrier between the light source  162  and/or the optical layer  163  and an environment of the key assembly  108 . Below the light source  162 , light assembly  160  may include electrical traces  164  positioned on the deformable layers  150 ,  151 . The electrical traces  164  may provide electrical power to the light source  162 , which may be used to selectively activate the light source  162  such that light source  162  emits light toward the illuminable symbol  111 . The electrical traces  164  may be coupled with a processing unit and/or other component including computer executable logic that may allow the light source  162  to be selectively operable and/or dynamically modifiable based on one or more functions or commands of an electronic device (e.g., electronic device  104  of  FIG. 1 ). 
     As shown in  FIG. 3A , the light assembly  160  is positioned on the first deformable layer  150 . In this regard, the electrical traces  164  may be positioned on or connected to the first deformable layer  150 . The first electrical terminal  156  of the key switch, described above, may also be positioned on the first deformable layer  150 . In particular, a first or top surface of the first deformable layer  150  may be connected to, or otherwise support or integrate, the electrical traces  164  and a second or bottom surface of the first deformable layer  150  may connected to, or otherwise support or integrate, the first electrical contact  156 . This may allow the first deformable layer  150  to be used both as a light guide and a component of a contact-based key switch. When the first deformable layer  150  deforms into the cavity  154 , the first electrical terminal  156  may electrically couple to, and/or physically contact, the second electrical terminal  157  in order to generate an input signal. In other embodiments, the first electrical terminal  156  may electrically couple to a different element of an embodiment to provide other functionality. 
     The light assembly  160  may be configured to direct or couple light into the tactile dome  132  positioned below the key cap  110 . This may allow the tactile dome  132  to be used as a light pipe or conduit that may propagate light between, for example, the light source  162  and the illuminable symbol  111 . In this regard, the tactile dome  132  may having a translucent portion, as described herein. For example, the tactile dome  132  may be constructed from silicon, rubber, metal or other elastically deformable material that may include translucent or light transmissible regions, as may be appropriate for a given application. 
     The light assembly  160  may be arranged in various configurations and positions within the key assembly  108  relative to the light integrated sensing membrane  136  in order to illuminate the illuminable symbol  111  and optionally a portion of the tactile dome  132 . In the embodiment of  FIG. 3A , the light assembly  160  is arranged such that the light source  162  is positioned under or substantially aligned with the contact feature  134  of the tactile dome  132 . The contact feature  134  may be a nub or other protrusion, which extends from or along an underside of the tactile dome  132 . Accordingly, and as shown in  FIG. 3F , when the tactile dome  132  collapses or buckles, the contact feature  134  may contact the light assembly  160  and partially or fully surround the light source  162 . This may allow light from the light source  162  to couple into the tactile dome  132 . In other cases, as described in greater detail below with respect to  FIG. 4F , the light assembly  160  may be positioned about a periphery of the tactile dome  132 , for example, such as about the base  135  of the tactile dome  132 . This may allow light from the light source  162  to couple into, and propagate through, the tactile dome  132 , which may be at least partially directed and/or channeled by a wall  139  of the tactile dome  132 , as described herein. 
     With reference to  FIG. 3B , the light assembly  160  is shown in a configuration in which the protective coating  166  may be used as a light guide. For example, the protective coating  166  may be a translucent material that is configured to receive and direct light to a specified region within the key assembly  108 . To illustrate, the light source  162  may be a side firing mLED that is configured to emit light substantially along light path L 2 . The light path L 2  may extend along a longitudinal direction of the protective coating  166 , which may allow light to enter a translucent body of the protective coating  166  and propagate therethrough. To facilitate the foregoing, the light assembly  160  may include reflective components  167 . The reflective component  167  may be positioned within, or partially within, the protective coating  166  and about the light source  162 . The reflective components  167  may exhibit a reflective characteristic that helps redirect light emitted from the light source  162  into the body of the protective coating  166 . 
     The protective coating  166  may also include at least one light extraction feature, such as light extraction feature  168  shown in  FIG. 3B . The light extraction feature  168  may be positioned away from the light source  162  and configured to expel light from the protective coating  166 . The light extraction feature  168  may be a textured surface, a lens, an aperture, and/or other region of the protective coating  166  that is configured to propagate light away from the light assembly  160 , for example, and toward the key cap  110 . In this regard, the protective coating  166  may be configured to receive light from the light source  162  and direct the received light to the light extraction feature  168 . As shown in  FIG. 3B , the light extraction feature  168  is separated or spaced apart from the light source  162 . As such, the light extraction feature  168  may be placed in any appropriate position along the protective coating  166  to facilitate illumination of an illuminable symbol of the key cap  110 . In some cases, the light extraction feature  168  may be positioned along the protective coating  166  such that the illuminable symbol of the key cap  110  exhibits a desired optical effect, such as enhancing brightness or altering a visible color of the illuminable symbol on the key cap  110 . 
     With reference to  FIG. 3C , the light assembly  160  is shown in a configuration in which the protective coating  166  is positioned over the light source  162 . The protective coating  166  may be an optical epoxy or other translucent material that is formed over the light source  162 . The protective coating  166  may be doped with phosphor or other appropriate material. In this manner, the protective coating  166  may help control an optical characteristic of light emitted from the light source  162 , including controlling a color, brightness, sharpness, and/or direction of the emitted light. The protective coating  166  may be applied to the light source  162  via an overmolding process. For example, the light source  162  and associated electrical traces  164  may be positioned along the first deformable layer  150 , and may deform with the deformable layer. The protective coating  166  may be a moldable material that is flowed or formed over the light source  162 , electrical traces  164 , the first deformable layer  150  and/or other components of the key assembly  108 . The overmolding of the protective coating  166  may help secure the light assembly within the light integrated sensing membrane  136 . The light source  162  may be oriented and/or arranged in a configuration that corresponds with an optical and/or structure characteristic of the overmolded protective coating  166 . For example, the light source  162  may be a top, rear, and/or side firing mLED as may be appropriate for a given configuration of the overmolded protective coating  166 . 
     With reference to  FIG. 3D , a top view of the electrical traces  164  of the light integrated sensing membrane  136  is shown. The electrical traces  164  may be used to route electrical signals to multiple light sources of a keyboard, such as light source  162 . Generally, the electrical traces  164  may be arranged in a parallel type circuit that may selectively route electrical signals to various ones of the light sources. It will be appreciated, however, that in other embodiments the electrical traces  164  may be arranged in various other circuit patterns and constructions. Further, insofar as the electrical traces are formed on the deformable layer, they may also deform, move, or the like as the deformable layer moves or otherwise deforms. 
     With reference to  FIG. 3E , a top view of the first and second electrical terminals  156 ,  157  of the light integrated sensing membrane  136  are shown. The first and second electrical terminals  156 ,  157  may be used to route electrical signals to various key assemblies across a keyboard. The first and second electrical terminals  156 ,  157  may be arranged in a grid and separated from one another by the cavity  154  (as described with respect to  FIG. 3A ). When the first and second electrical terminals  156 ,  157  electrically couple to and/or physically contact one another (that is, when the deformable layers collapse or deform into the cavity), the light integrated sensing membrane  136  may trigger a switch event. Accordingly, and as shown in  FIG. 3E , an array of contact regions  158  may be defined where the first and second electrical contacts overlap or pass over one another. The light integrated sensing membrane  136  may receive a force input at or near one or more of the array of contact regions  158  and cause the first and second electrical contacts to contact one another at the respective one of the array of contact regions  158  and trigger a corresponding switch event. In this regard, the array of contact regions  158  may correspond to regions of a keyboard in which an individual key assembly is positioned (e.g., key assembly  108  of  FIG. 1 ). It will be appreciated, however, that in other embodiments, the first and second electrical terminals  156 ,  157  may be arranged in various other circuit patterns and constructions. 
     With reference to  FIG. 3F , the light integrated sensing membrane  136  is shown in an actuated configuration. In an actuated configuration, the tactile dome  132  may press down onto the light integrated sensing membrane  136  in response to a force F (which may be exerted on the tactile dome  132  by a key cap receiving a mechanical press). The force F may cause the tactile dome  132  to collapse or buckle, for example, as shown in  FIG. 3F . In a buckled state, the contact feature  134  may exert a force on the light integrated sensing membrane  136 . In particular, the contact feature  134  may exert a force on the light integrated sensing membrane  136  that causes the first and second deformable layers  150 ,  151  to be pinched, squeezed, translated, or otherwise deform such that the first and second deformable layers  150 ,  151  move toward one another to electrically couple to, and potentially physically contact, one another. This motion may cause one or both of the deformable layers to deform into the cavity. Movement of the first and second deformable layers  150 ,  151  may cause the first and second electrical terminals  156 ,  157  to contact one another and trigger a switch event. When the first and second deformable layers  150 ,  151  translate by the action of the contact feature  134 , a portion of the light integrated sensing membrane  136  may extend into the relief  148 . The relief  148  may thus be used to provide a desired tactile response to the key cap  110  during actuation and/or further reduce the stack-up height, as described herein. 
       FIG. 3F  depicts the contact feature  134  of the tactile dome  132  contacting the light assembly  160 . In particular, the contact feature  134  is shown at least partially encompassing or surrounding the light source  162  when the tactile dome  132  is depressed toward the light integrated sensing membrane  136 . In the collapsed state, the tactile dome  132  may be used as light pipe or light conduct that directs light between the light source  162  and an illuminable symbol positioned above the tactile dome  132 . For example, the light path L 1  may extend from the light source  162  and couple directly into the tactile dome  132  at the contact feature  134  when collapsed. The tactile dome  132  may be configured to expel the light received from the light assembly  160  in a particular manner, for example, such as allowing the light to escape from the tactile dome  132  along a surface of the tactile dome  132  that is positioned along an underside of a key cap. This may allow the light assembly  160  (in conjunction with the optically coupled tactile dome  132 ) to illuminate the illuminable symbol  111  according to a predetermined optical effect (e.g., such as maximizing a brightness of the illuminable symbol on the key cap). 
       FIGS. 4A-4I  depict key assemblies  208   a - 208   i . As described herein, the key assemblies  208   a - 208   i  may be configured to operate in a manner substantially analogous to the key assembly  108  described with respect to  FIGS. 1-3F . For example, the key assemblies  208   a - 208   i  may include a key cap configured to receive a force input or mechanical press that is used to collapse or buckle a tactile dome positioned below the key cap. Upon buckling, the tactile dome may contact a light integrated sensing membrane and trigger a switch event that may be used to control a function of a computing device (e.g., electronic device  104  of  FIG. 1 ). Accordingly, the key assemblies  208   a - 208   i  may include similar components as that of key assembly  108 , including a key cap  210 , a tactile dome  232 , a contact feature  234 , a base  235 , a wall  239 , a feature plate  242 , and a relief  248 . The key assemblies  208   a - 208   i  may also include a light integrated sensing membrane that includes a light source (mLED) and electrical terminals of a key switch and/or another element for detecting a key press, according to the embodiments described with respect to  FIGS. 4A-4I . 
     With reference to  FIG. 4A , a cross-sectional view of the key assembly  208   a  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4A , the key assembly  208   a  includes a light integrated sensing membrane  236   a . The light integrated sensing membrane  236   a  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   a  may be configured to illuminate an illuminable symbol of the key assembly  208   a  and trigger a switch event. In particular, the light integrated sensing membrane  236   a  includes at least one deformable layer having electrical terminals for a contact-based key switch and electrical traces for a mLED or other appropriate light source. Accordingly, the light integrated sensing membrane  236   a  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   a , a second deformable layer  251   a , a spacer layer  252   a  separating the deformable layers  250   a ,  251   a , a cavity  254   a , a first electrical terminal  256   a , a second electrical terminal  257   a , light assembly  260   a , light source  262   a , optical layer  263   a , electrical traces  264   a , and protective coating  266   a.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4A , the light assembly  260   a  may be positioned along the second deformable layer  251   a . In particular, the light assembly  260   a  may be positioned along a bottom surface of the second deformable layer  251   a . In this regard, the light source  262   a  of the light assembly  260   a  may extend below the second deformable layer  251   a  and at least partially into the relief  248  of the feature plate  242 . This may reduce the z-profile of the key assembly  208   a  by allowing some or all of the volume of the light source  262   a  to be positioned within a region defined by a thickness of the feature plate  242 . In the embodiment of  FIG. 4A , the light source  262   a  may be a rear firing mLED that may project light through the light integrated sensing membrane  236   a  (e.g., through the first and second deformable layers  250   a ,  251   a ) and toward an illuminable symbol of key cap  210 . In other cases, other configurations of the light source are contemplated, including side and top firing mLED, which may be used to direct light toward various other portions of the key assembly  208   a  and/or create various different optical effects at the key cap  210 . 
     With reference to  FIG. 4B , a cross-sectional view of the key assembly  208   b  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4B , the key assembly  208   b  includes a light integrated sensing membrane  236   b . The light integrated sensing membrane  236   b  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   b  may be configured to illuminate an illuminable symbol of the key assembly  208   b  and trigger a switch event. In particular, the light integrated sensing membrane  236   b  includes at least one deformable layer having electrical terminals for a contact-based key switch and deformable electrical traces for a mLED or other appropriate light source. That is, the electrical terminals may electrically couple to one another upon physical contact, when the at least one deformable layer deforms a sufficient distance. Accordingly, the light integrated sensing membrane  236   b  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   b , a second deformable layer  251   b , a spacer layer  252   b  separating the deformable layers  250   b ,  251   b , a cavity  254   b , a first electrical contact  256   b , a second electrical contact  257   b , light assembly  260   b , light source  262   b , optical layer  263   b , electrical traces  264   b , and protective coating  266   b.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4B , the light assembly  260   b  may be at least partially recessed into, or encapsulated by, the first deformable layer  250   b . In particular, the light assembly  260   b  may be positioned along the first deformable layer  250   b  such that the light source  262   b  extends partially or fully into a thickness of the first deformable layer  251   b . As shown in  FIG. 4B , the first deformable layer  250   b  may include a pocket  278 . The pocket  278  may be a recess or groove formed into a surface of the first deformable layer  250   b . The pocket  278  may be configured to receive the light source  262   b  such that the pocket  278  surrounds or conforms to a shape of the light source  262   b . In some cases, as shown in  FIG. 4B , a protective coating  280  may be applied above the light assembly  260   b . The protective coating  280  may form a barrier between the light assembly  260   b  and an environment of the key assembly  208   b  and/or dampen the impact of the contact feature  234  when the tactile dome  232  buckles and contacts the light integrated sensing membrane  236   b.    
     Recessing the light assembly  260   b  at least partially into the first deformable layer  250   b  may enhance the ability of the light integrated sensing membrane  236   b  to function as a light guide. As described above, one or both of the first and second deformable layer  250   b ,  251   b  may be used generally as a light guide or light conduit. For example, one or both of the first and second deformable layers  250   b ,  251   b  may be a translucent or light transmissible structure that is used to propagate light throughout the key assembly  208   b . When the light source  262   b  is positioned within the pocket  278 , as shown in  FIG. 4B , light may be optically coupled with the first deformable layer  250   b  along a longitudinal direction of the first deformable layer  250   b . This may allow the first deformable layer  250   b  to propagate light received from the light source  262   b  along a greater distance and/or prevent light leakage within the key assembly  208   b . While the embodiment depicted with respect to  FIG. 4B  is shown with light assembly  260   b  recessed with respect to the top surface of the first deformable layer  250   b , it will appreciated that other configurations are contemplated within the scope of the present disclosure, including arranging the light assembly  260   b  so that the light source  262   b  is recessed within a bottom surface of the first deformable  250   b , a top surface of the second deformable layer  251   b , a bottom surface of the second deformable layer  251   b  and/or any other appropriate configuration. 
     With reference to  FIG. 4C , a cross-sectional view of the key assembly  208   c  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4C , the key assembly  208   c  includes a light integrated sensing membrane  236   c . The light integrated sensing membrane  236   c  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   c  may be configured to illuminate an illuminable symbol of the key assembly  208   c  and trigger a switch event. In particular, the light integrated sensing membrane  236   c  includes at least one deformable layer having electrical terminals for a contact-based key switch and electrical traces for a mLED or other appropriate light source. As the deformable layer deforms, the electrical traces may likewise move or otherwise deform. Accordingly, the light integrated sensing membrane  236   c  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   c , a second deformable layer  251   c , a spacer layer  252   c  separating the first and second deformable layers, a cavity  254   c , an electrical contact  257   c , light assembly  260   c , light source  262   c , optical layer  263   c , and protective coating  266   c.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4C , the light assembly  260   c  may be positioned along a bottom surface of the first deformable layer  250   c . In particular, the light assembly  260   c  may be positioned along the bottom surface of the first deformable layer  250   c  such that the light source  262   c  extends at least partially into the cavity  254   c . This may reduce the z-profile of the key assembly  208   c  by allowing some or all of the volume of the light source  262   c  to be positioned within a region defined by a thickness of the spacer layer  252   c  separating the first and second deformable layers  250   c ,  251   c.    
     The light source  262   c  may be electrically coupled with electrical traces  256   c  that are coupled with, or formed on, the first deformable layer  250   c  and extend into the cavity  254   c . The electrical traces  256   c  may be configured to selectively provide an electrical signal to the light source  262   c  that may cause the light source  262   c  to emit light toward an illuminable symbol of key cap  210 . The electrical traces may deform as the deformable layer deforms. The first deformable layer  250   c  may also include electrical terminals or a key switch (not shown in  FIG. 4C ) that cooperate with the electrical contact  257   c  positioned along the second deformable layer  251   c  to complete an electrical circuit or switch in response to a collapsing or buckling of the tactile dome  232 . Accordingly, the same surface of the first deformable layer  250   c  may be used to mount or couple with the electrical terminals of the key switch and the electrical traces of the light source  262   c.    
     With reference to  FIG. 4D , a cross-sectional view of the key assembly  208   d  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4D , the key assembly  208   d  includes a light integrated sensing membrane  236   d . The light integrated sensing membrane  236   d  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   d  may be configured to illuminate an illuminable symbol of the key assembly  208   d  and trigger a switch event. In particular, the light integrated sensing membrane  236   d  includes at least one deformable layer having electrical terminals for a contact-based key switch and electrical traces for a mLED or other appropriate light source. Accordingly, the light integrated sensing membrane  236   d  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   d , a second deformable layer  251   d , a spacer layer  252   d , a cavity  254   d , light assembly  260   d , light source  262   d , optical layer  263   d , electrical traces  264   d , and protective coating  266   d.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4D , the light assembly  260   d  may be positioned along a top surface of the second deformable layer  251   d . In particular, the light assembly  260   d  may be positioned along a top surface of the second deformable layer  251   d  such that the light source  262   d  extends at least partially into the cavity  254   d . This may reduce the z-profile of the key assembly  208   d , by allowing some or all of the volume of the light source  262   d  to be positioned within a region defined by a thickness of the spacer layer  252   d.    
     In the embodiment of  FIG. 4D , the light integrated sensing membrane  236   d  may include an optical-based switch that detects variations in reflected light to estimate a force received along the first deformable layer  250   d . For example, the light integrated sensing membrane  236   d  may include an optical sensor  290  positioned on the top surface of the second deformable layer  251   d . The optical sensor  290  may be a micro photo sensor that is configured to be positioned within the cavity  254   d . The optical sensor  290  may detect light emitted from the light assembly  260   d  and determine a relative position of the first deformable layer  250   d . To facilitate the foregoing, the light integrated sensing membrane  236   d  may include a reflective component  292 . The reflective component  292  may be positioned along the bottom surface of the first deformable layer  250   d  and within or partially within the cavity  254   d . The optical sensor  290  may detect the reflection or propagation of light emitted from the light assembly  260   d  substantially along a light path L 3  to estimate movement of the first deformable layer  250   d . For example, movements of the first deformable layer  250   d  may alter the distance of the light path L 3 , which may be detectable by the optical sensor  290 . As described herein, the first deformable layer  250   a  may bend or deform into the cavity  254   d  in response to a collapsing or buckling of the tactile dome  232  (which may be caused by a mechanical press exerted on a key cap positioned above the tactile dome  132 ). As such, the optical sensor  290  may correlate the altered light path L 3  with the bending of the first deformable layer  250   a  to estimate a force input received by an associated keyboard key, such as key cap  210 . 
     With reference to  FIG. 4E , a cross-sectional view of the key assembly  208   e  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4E , the key assembly  208   e  includes a light integrated sensing membrane  236   e . The light integrated sensing membrane  236   e  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   e  may be configured to illuminate an illuminable symbol of the key assembly  208   e  and trigger a switch event. In particular, the light integrated sensing membrane  236   e  includes at least one deformable layer having electrical terminals for a contact-based key switch and electrical traces for a mLED or other appropriate light source. Accordingly, the light integrated sensing membrane  236   e  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   e , a second deformable layer  251   e , a spacer layer  252   e  separating the deformable layers, a cavity  254   e , a first electrical contact  256   e , a second electrical contact  257   e , light assembly  260   e , light source  262   e , optical layer  263   e , electrical traces  264   e , and protective coating  266   e.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4E , the light assembly  260   e  may be positioned along a top surface of the first deformable layer  250   a  and separated or offset from the tactile dome  232 . In particular, the light assembly  260   e  may be positioned adjacent the base  235  of the tactile dome such that the light source  262   e  is positioned about a periphery of the tactile dome  232 . In this regard, the light source  262   e  may be a side firing mLED that is configured to propagate light towards the tactile dome  232 . However, in other embodiments, the light source  262   e  may be a top firing mLED that may be configured to illuminate an illuminable symbol of a key cap positioned above the tactile dome  232  without using the tactile dome  232  as a light guide or light conduit, which may be the case where the tactile dome  232  is formed from a non-transparent material or includes select non-transparent regions. 
     With reference to  FIG. 4F , a cross-sectional view of the key assembly  208   f  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4F , the key assembly  208   f  includes a light integrated sensing membrane  236   f . The light integrated sensing membrane  236   f  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   f  may be configured to illuminate an illuminable symbol of the key assembly  208   f  and trigger a switch event. In particular, the light integrated sensing membrane  236   f  includes at least one deformable layer having electrical terminals for a contact-based key switch and electrical traces for a mLED or other appropriate light source. Accordingly, the light integrated sensing membrane  236   f  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   f , a second deformable layer  251   f , a spacer layer  252   f  separating the deformable layers, a cavity  254   f , a first electrical contact  256   f , a second electrical contact  257   f , light assembly  260   f , light source  262   f , optical layer  263   f , electrical traces  264   f , and protective coating  266   f.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4F , the light assembly  260   f  may be at least partially positioned within (e.g., surrounded by) the tactile dome  232 . In particular, the light assembly  260   f  may be positioned along a top surface of the first deformable layer  250   f  such that the light source  262   f  is aligned with a base  235  of the tactile dome  232 . In some cases, as shown in  FIG. 4F , the light source  262   f  is positioned within a recess  240  of the tactile dome  232 . The recess  240  may be a groove or opening that extends partially or fully through the base  235  of the tactile dome  232 . The recess  240  may be configured to receive the light source  262   f  such that the recess surrounds or conforms to a shape of the light source  262   f.    
     The recess  240  may allow the tactile dome  232  to function as a light conduit or light pipe within the key assembly  208   f . The tactile dome  232  may surround or partially surround the light source  262   f  such that light emitted from the light source  262   f  is directed into a light-transmissible (translucent) body of the tactile dome  232 . For example, the light source  262   f  may emit light substantially along light path L 4  which may extend into the tactile dome  232  at the base  235  and along or through the walls  239  of the tactile dome  232 . In some cases, the walls  239  may include reflective or treated surfaces that may help retain light within the tactile dome  232  as the light travels toward a key cap positioned above the tactile dome  232 . This may allow the tactile dome  232  to direct light received toward a specified portion of the key cap  210 , for example, such as a light transmissible underside of the key cap associated with an illuminable symbol and/or prevent light leakage within the key assembly  208   f . In some cases, the tactile dome  232  may direct light to the specified portion of the key cap depending on the particular shape or contour of the illuminable symbol and cause the light assembly  260   f  to illuminate the illuminable symbol according to a predetermined optical effect (e.g., such as maximizing a brightness of the illuminable symbol on the key cap). 
     With reference to  FIG. 4G , a cross-sectional view of the key assembly  208   g  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4G , the key assembly  208   g  includes a light integrated sensing membrane  236   g . The light integrated sensing membrane  236   g  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   g  may be configured to illuminate an illuminable symbol of the key assembly  208   g  and trigger a switch event. In particular, the light integrated sensing membrane  236   g  includes at least one deformable layer having electrical terminals for a contact-based key switch and electrical traces for a mLED or other appropriate light source. That is, the electrical terminals may electrically couple to one another to output a signal upon deformation of the at least one deformable layer. Accordingly, the light integrated sensing membrane  236   g  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   g , a second deformable layer  251   g , a spacer layer  252   g  separating the deformable layers, a cavity  254   g , a first electrical contact  256   g , a second electrical contact  257   g , light assembly  260   g , light source  262   g , optical layer  263   g , and protective coating  266   g.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4G , the light assembly  260   g  may be positioned along a top surface of the second deformable layer  251   g  and extend into one or both of the spacer layer  252   g  and the first deformable layer  250   g . In particular, the light assembly may be positioned along the second deformable layer  251   g  such that the light source  262   g  extends through an opening or through a portion of one or both of the spacer layer  252   g  and the first deformable layer  250   g . The light source  262   g  shown in  FIG. 3G  may be a side firing mLED that is configured to direct light substantially along light path L 5 . The light path L 5  may extend along a longitudinal direction of the light integrated sensing membrane  236   g  such that light from the light source  262   g  may propagate through the spacer layer  252   g  and/or the first deformable layer  250   g . In this regard, the spacer layer  252   g  and/or the first deformable layer  250   g  may be used as a light guide (or otherwise define an optical path) to transfer or propagate light between various regions within the key assembly  208   g , including propagating the light toward an illuminable symbol of the key cap  210 . 
     With reference to  FIG. 4H , a cross-sectional view of the key assembly  208   h  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4H , the key assembly  208   h  includes a light integrated sensing membrane  236   h . The light integrated sensing membrane  236   h  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   h  may be configured to illuminate an illuminable symbol of the key assembly  208   h  and trigger a switch event. In particular, the light integrated sensing membrane  236   h  includes at least one deformable layer having electrical terminals for a contact-based key switch and electrical traces for a mLED or other appropriate light source. Accordingly, the light integrated sensing membrane  236   h  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   h , a second deformable layer  251   h , a spacer layer  252   h  separating the deformable layers, a cavity  254   h , a first electrical contact  256   h , a second electrical contact  257   h , light assembly  260   h , light source  262   h , optical layer  263   h , electrical traces  264   h , and protective coating  266   h.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4H , the light assembly  260   h  may be positioned at least partially within the first deformable layer  250   h . In particular, the light assembly  260   h  may be arranged within a thickness of the first deformable layer  250   h  such that the light source  262   h  is positioned along a longitudinal direction of the first deformable layer  250   h . In some cases, as shown in  FIG. 4H , the light source  262   h  may be encapsulated or enclosed within the optical layer  263   h  and/or the protective coating  266   h  within the first deformable layer  250   h . The light source  262   h  shown in  FIG. 4H  may be a side firing mLED that is configured to direct light substantially along light path L 6 . The light path L 6  may extend along a longitudinal direction of the light integrated sensing membrane  236   h  such that light from the light source  262   h  may propagate through the first deformable layer  250   h . In this regard, the first deformable layer  250   h  may be used as a light guide to transfer or propagate light between various regions within the key assembly  208   h , including propagating the light toward an illuminable symbol of the key cap  210 . 
     With reference to  FIG. 4I , a cross-sectional view of the key assembly  208   i  is shown taken along line A-A of  FIG. 1 . As shown in  FIG. 4I , the key assembly  208   i  includes a light integrated sensing membrane  236   i . The light integrated sensing membrane  236   i  may be configured to operate in a manner substantially analogous to the light integrated sensing membrane  136  described with respect to  FIGS. 1-3F . For example, the light integrated sensing membrane  236   i  may be configured to illuminate an illuminable symbol of the key assembly  208   i  and trigger a switch event. In particular, the light integrated sensing membrane  236   i  includes at least one deformable layer having electrical terminals for a contact-based key switch and electrical traces for a mLED or other appropriate light source. Accordingly, the light integrated sensing membrane  236   i  may include similar components as that of the light integrated sensing membrane  136 , including a first deformable layer  250   i , a second deformable layer  251   i , a spacer layer  252   i , a cavity  254   i , a first electrical contact  256   i , a second electrical contact  257   i , light assembly  260   i , light source  262   i , optical layer  263   i , and protective coating  266   i.    
     Notwithstanding the foregoing, in the embodiment of  FIG. 4I , the light assembly  260   i  may be at least partially positioned within the spacer layer  252   i . In particular, the light assembly  260   i  may be arranged within a thickness of the spacer layer  252   i  such that the light source is positioned along a longitudinal direction of the spacer layer  252   i . In some cases, as shown in  FIG. 4I , the light source  262   i  may be encapsulated or enclosed within the optical layer  263   i  and/or the protective coating  266   i  within the spacer layer  252   i . The light source  262   i  shown in  FIG. 4I  may be a side firing mLED that is configured to direct light substantially along light path L 7 . This light path L 7  may extend along a longitudinal direction of the light integrated sensing membrane  236   i  such that light from the light source  262   i  may propagate through the spacer layer  252   i . In this regard, the spacer layer  252   i  may be used as a light guide to transfer or propagate light between various regions within the key assembly  208   i , including propagating the light toward an illuminable symbol of the key cap  210 . 
     Other examples and implementations are within the scope and spirit of the disclosure and appended claims. For example, features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations. Similarly, although embodiments have been discussed in the context of keys of a keyboard, other input mechanisms may incorporate or form embodiments described herein. As an example, trackpads, mice, buttons, touch-sensitive surfaces, and the like may all incorporate structures and/or methods of operation described herein. Also, as used herein, including in the claims, “or” as used in a list of items prefaced by “at least one of” indicates a disjunctive list such that, for example, a list of “at least one of A, B, or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Further, the term “exemplary” does not mean that the described example is preferred or better than other examples. 
     The foregoing description, for purposes of explanation, uses specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of the specific embodiments described herein are presented for purposes of illustration and description. They are not targeted to be exhaustive or to limit the embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings.

Metadata:
Filing Date: 20191008
Publication Date: 20210413
Grant Date: 20210413
Priority Date: 20170607
Inventors: WANG, PAUL X.
Assignee: APPLE INC
CPC Classifications: [{"code": "H03K17/955", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0216", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01H2219/036", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01H13/83", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01H2219/062", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0202", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/023", "inventive": true, "first": false, "tree": "[]"}, {"code": "H03K17/975", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01H13/703", "inventive": true, "first": false, "tree": "[]"}, {"code": "H03K17/98", "inventive": true, "first": false, "tree": "[]"}, {"code": "H03K2217/9653", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0221", "inventive": true, "first": true, "tree": "[]"}, {"code": "H03K2217/9653", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01H2215/004", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0233", "inventive": true, "first": false, "tree": "[]"}, {"code": "H03K2217/9653", "inventive": false, "first": false, "tree": "[]"}, {"code": "H03K17/955", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0233", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0216", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01H13/703", "inventive": true, "first": false, "tree": "[]"}, {"code": "H03K17/98", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0221", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 68165200