Abstract:
Key switch mechanisms are typically used for mediating user input to computing devices. A key switch mechanism provides immediate tactile feedback to a user upon user-actuation thereof. Unlike touchscreen interfaces, existing key switch mechanisms of conventional keyboards do not provide a user with a dynamically changeable interface. Described is a key switch mechanism that comprises a circuit module, a key cap and a linkage mechanism for guiding travel of the key cap substantially along a travel axis. The linkage mechanism comprises a positioning board and a main link pivotably inter-coupling the positioning board and the key cap. The main link substantially impedes tilt of the key cap away from the travel axis during travel of the key cap therealong from a released position, whereat the key cap is biased, to a depressed position whereat a control signal is generated.

Description:
TECHNICAL FIELD 
     The present disclosure relates generally to a key switch mechanism that includes a key cap, a circuit module and a linkage mechanism which includes a positioning board and a set of main links. The key cap includes an optically transmissive portion and with the linkage mechanism, a tactile feedback to a user upon user-effectuated or user-directed actuation or displacement of said key caps can be experienced. The key cap includes a protrusion disposed at a periphery of the said key cap for contacting a switch electronically coupled to the circuit module. By contacting the switch, electronic signals can be activated. 
     BACKGROUND 
     Key switch mechanisms are constituents of computer or machine operated devices such as a keyboard. They are conventionally used for facilitating, enabling, or mediating user input to computing devices (e.g., desktop computers and laptops). A key switch mechanism has the function or advantage of providing immediate, or substantially immediate, tactile feedback to a user upon user-actuation of key(s) on the mechanism. A conventional key switch mechanism typically has multiple keys arranged in rows and representing different alphanumeric characters. 
     A keycap is typically a small plastic cover that is carried by a computer keyboard. Keycaps are conventionally used to indicate or display the alphanumeric character that they correspond to or the function that is associated therewith. Generally, user-effectuated displacement or depression of a keycap results in an actuation of a corresponding key switch that is positioned underneath said keycap. Recently, there are several modifications to keyboards, key switch mechanism, as well as keycaps. For instance, keyboards or key switch mechanisms configured to allow light to shine through specific portions or areas of the keyboards or key switch mechanisms have been developed. The illumination of specific areas, or of specific key caps, on the keyboard can help to distinguish different areas of the keyboard, as well as different key caps on the keyboard, from each other. U.S. Pat. No. 4,449,024 discloses an illuminated keyboard that allows light to shine through specific keycaps. In addition, U.S. patent application Ser. No. 9/755,062 discloses keyboards with keycaps that each has a different transparent alphanumeric designation. Each keycap of the keyboard of U.S. Ser. No. 9/755,062 has an opaque housing and a transparent alphanumeric designation. Light is only transmissible through the transparent alphanumeric designation to thereby enable differentiation between the different keys carried by the keyboard. 
     A significant drawback or limitation associated with conventional keyboards is the static information, for instance static letters and numbers, that are displayed by individual key caps of said keyboards. Unlike touchscreen interfaces, existing conventional keyboards do not provide a user with dynamically changing interface via which a user can introduce inputs, instructions, and/or commands. 
     Touchscreen interfaces are becoming increasingly popular. Computers and other electronic products that incorporate a touchscreen, for example the Apple iPhone™, provide users with a relatively more intuitive way of controlling (e.g., providing input to) said computers. In addition, touchscreen interfaces allow programmers to provide customized interfaces, which can be required and/or advantageous with particular applications. However, a common disadvantage associated with conventional touchscreen interfaces is a lack of a robust haptic or tactile feedback to users to confirm user-directed touchscreen inputs. 
     Haptic touchscreen interfaces (i.e., touchscreen interfaces that provides a tactile feedback to users upon touchscreen inputs) have generated increasing commercial interest. For example, LG© and Samsung© have introduced handsets and mobile phones that incorporate vibration-based haptic feedback systems. However, such vibration-based haptic feedback systems are relatively complex and costly to manufacture, assemble, and/or maintain. In addition, vibration-based haptic feedback systems may not be suitable for rapid and/or short-duration multiple consecutive user-inputs. 
     U.S. patent application Ser. No. 11/388,224 discloses a lid structure that can be positioned relative to, for instance on the surface of, a touchscreen interface for providing tactile feedback to a user. The lid structure can be shaped and configured to guide a user&#39;s finger(s) to a desired position on the touchscreen. However, there are ergonomic disadvantages or issues associated with the lid structure of U.S. Ser. No. 11/388,224. In addition, the lid structure of U.S. Ser. No. 11/388,224 is not robust enough for providing fast and/or accurate tactile feedback associated with specific individual user inputs via the touchscreen. 
     In addition, U.S. patent application Ser. No. 10/235,162 discloses a touchscreen tactile feedback system. With the touchscreen tactile feedback system of U.S. Ser. No. 10/235,162 a keyboard including keys mechanically interfaces with a touchscreen panel. The keys of the keyboard can be physically displaced by a user for contacting the touchscreen panel and thereby enable user-directed input via said touchscreen panel. The physical displacement of the keys provides the user with a tactile response or feedback associated with the user-directed input. 
     However, existing touchscreens are generally unable to support, accommodate, or keep up with rapid user actuation or input, for example user-effectuated consecutive actuations of more than 100 actuations or inputs per minute). Therefore, the use of touchscreens may not be suitable for applications in which rapid user actuation or input is routinely necessary and/or desired, for instance for gaming applications. 
     SUMMARY 
     One of the objects of certain exemplary aspects of the present disclosure is to address the aforementioned exemplary problems and/or to overcome the exemplary deficiencies commonly associated with optically transmissive key switch mechanisms as described herein. Accordingly, for example, provided and described herein are certain exemplary embodiments of exemplary optically transmissive key switch mechanisms. 
     According to one aspect of this disclosure, there is provided a key switch mechanism. The key switch mechanism comprises a circuit module, a key cap having a top portion and a side wall extending therefrom, and a linkage mechanism for guiding travel of the key cap substantially along a travel axis between a depressed position and a released position. The linkage mechanism comprises a positioning board spatially displaced from the circuit module, the positioning board defining an aperture shaped and dimensioned for receiving the key cap therethrough; and a main link pivotably coupled to the positioning board, the main link further being pivotably coupled to the exterior of the side wall of the key cap, the main link for substantially impeding tilt of the key cap away from the travel axis during travel of the key cap through the aperture of the positioning board. The circuit module biases the key cap towards the released position and generates a control signal when the key cap is displaced to the depressed position. 
     In some embodiments, the main link is a rigid wire comprising two ends terminating in corresponding two apertures defined in the side wall of the key cap, the two cavities being shaped and inter-aligned for pivoting of the main link thereabout. 
     In some other embodiments, the linkage mechanism further comprises a second main link pivotably coupled to the positioning board and the exterior of the side wall of the key cap, the main link and the second main link being in a parallel configuration with the key cap for further impeding tilt of the key cap from the travel axis. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the disclosure are described hereinafter with reference to the following drawings, in which: 
         FIG. 1A  shows a key switch mechanism comprising a key cap, a circuit module and a linking mechanism comprising a positioning board and a set of main links. 
         FIG. 1B  shows a 2-dimensional view of the key switch mechanism on a first plane. 
         FIG. 2A  is a plan view of they key cap including a top portion and a bottom portion opposite the top portion. 
         FIG. 2B  is a perspective view of the key cap including a top portion and a bottom portion opposite the top portion. 
         FIG. 2C  shows a key cap being positioned relative to a circuit module comprising an electronic circuitry. 
         FIG. 2D  shows a schematic illustration of a key switch mechanism that includes a plurality of optically transmissible tactile key caps which are coupled to, carried by, or disposed relative to a corresponding display screen that is carried by, or incorporated into, the circuit module. 
         FIG. 3A  shows a plan view of a base of a circuit module which defines an opening and the opening includes a corresponding switch. 
         FIG. 3B  shows a perspective view of a key cap with a circuit module comprising an opening with a corresponding actuator. 
         FIG. 3C  shows a cross sectional side view of a key cap with a circuit module in a first position (released position). 
         FIG. 3D  shows a side view of a key cap with a circuit module in a second position (depressed position). 
         FIG. 4A  shows a plan view of a positioning board with a key cap. 
         FIG. 4B  shows a side view of a positioning board with a key cap. 
         FIG. 4C  shows the positioning board defining an aperture which is shaped and dimensioned for receiving two key caps. 
         FIG. 4D  is a diagram of the at least one clasp extending from the bottom side of the positioning board. 
         FIG. 5A  shows a plan view of the key cap with the set of main links. 
         FIG. 5B  shows a side view of a key cap in a first position being secured to the clasp of the positioning board by way of two main links. 
         FIG. 5C  shows a side view of a key cap in a first position being secured to the clasp of the positioning board by way of one main link. 
         FIG. 5D  is a side view of the key cap in a second position. 
         FIG. 6A  shows key caps being arranged in a staggered array configuration. 
         FIG. 6B  shows a cantilever key cap mechanism which includes a key cap and two arms. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the present disclosure relate to a key switch mechanism that includes a key cap, a circuit module and a linking mechanism comprising a positioning board and a set of main links. The key cap includes a top end and a side wall extending therefrom. The key cap further includes an optically transmissive portion or region (also known as a light permeable or transmissive portion or region). The positioning board which is spatially displaced from the circuit module is shaped and dimensioned for receiving the key cap therethrough. The set of main links is pivotably coupled to the positioning board. The linking mechanism is configured for providing a tactile feedback to a user upon user-effectuated, user-controlled, or user-directed actuation or displacement of the key cap. 
     The key caps include a protrusion extending from the side wall away from the interior thereof. The protrusion is positioned or disposed at a periphery or perimeter of the key cap, for example along a side or edge of or at a corner of the key cap, or at a distance away from the key cap. The key caps can be coupled to, carried by, assembled or arranged onto, disposed relative to or across, or used with an optically transmissive surface or screen (or an optical display screen or surface). The optical display screen can be a rigid display screen, for example an LCD or LED based screen, or a flexible display screen, for example a polymer based screen configured as an organic LED (OLED) screen. The key caps can also be coupled to, carried by, assembled or arranged onto, disposed relative to or across, or used with a positioning board that carries or supports the key caps. 
     Each key cap, more specifically the protrusion of each key cap, can correspond to one actuator of the circuit module. The actuator is coupled to a switch which is electrically coupled to an electronic circuitry of the circuit module. Displacement of a particular key cap relative to said key cap&#39;s corresponding switch by way of the actuator can trigger, effectuate, or cause an activation or actuation of said switch. Activation or actuation of said switch can result in generation of electrical signal(s) by said switch. The generated electrical signal(s) are transmissible to an electronic or computing device (e.g., a desktop or laptop computer, a gaming console, or a mobile phone) coupled to the electronic circuitry of the circuit module. 
     In multiple embodiments, the key cap, more specifically the top side of the key cap includes or incorporates the optically transmissive (or light permeable) surface, portion, area, or window. The optically transmissive or light permeable surface, region, portion, area, or window can be referred to as a viewing area or a viewing window (e.g., an image viewing area or an image viewing window). Where the key cap is disposed or positioned adjacent or relative to, more specifically on top of or over a light-emitting surface (e.g., a display screen or surface such as a LCD screen), the light permeable portion or surface of the key cap allows transmission of light emitted from the light-emitting portion or surface, more specifically from the portion or area of the light-emitting surface corresponding to the light permeable portion or surface of the key cap, therethrough. The transmission of light through the light permeable portion or surface of the key cap allows a user to view or see images (e.g., icons, figures, and alphanumeric characters) displayed by the underlying surface (e.g., display screen or surface such as an LCD screen), more specifically by the area of the underlying surface corresponding to the light permeable portion or surface of the key cap. 
     The key cap, more specifically the protrusion of the key cap is displaceable, for instance relative to the optical display screen or surface. More specifically, the key cap, and hence the protrusion of the key cap can be displaced relative to a corresponding actuator and/or switch. The key cap can be displaced between a first position and a second position relative to the optical display screen or surface, wherein the second position is located in closer proximity to the optical display screen or surface as compared to the first position. 
     In many embodiments, the set of main links is shaped and/or configured to bias the key cap at the first position (also referred to as a rest position, a rest state, or an original position). The key cap is actuable (e.g., displaceable or moveable) from the first position to or towards the second position (also referred to as an actuated position or an actuated state) by a force applied onto, or transferred to, the key cap. The displacement of the key cap, for example from the first position to the second position, facilitates or effectuates a corresponding displacement of the switch by way of the actuator. In many embodiments, the displacement of the key cap at the second position correspondingly displaces the actuator for facilitating or effectuating actuation of a corresponding switch. For instance, the displacement of the key cap at the second position can effectuate contact between the actuator of said key cap and said key cap&#39;s corresponding switch. Such a contact can facilitate or effectuate activation or actuation of said switch and thereby effectuate generation of electrical signal(s) by said switch. 
     The tactile feedback provided to the user of the key cap upon or during actuation or displacement of said key cap (e.g., displacement from the first position to the second position) can be desirable, advantageous, important, and/or useful, particularly when applied to particular functions (e.g., gaming applications) wherein fast, discernible, easy, and/or accurate feedback, knowledge, and/or confirmation of key actuation is required and/or desired. The immediate, or substantially immediate, feedback, i.e., in the form of tactile sensation or feedback, provided by the key caps of embodiments of the present disclosure can be significantly useful and advantageous to a user&#39;s overall gaming experience. The key caps of various embodiments supports rapid consecutive actuations or displacements (e.g., at least 50, 100, 150, or more actuations or displacements per minute) thereof for contacting corresponding switches (e.g., electromechanical switches) and generating electrical signals transmissible to the computing device. This means that the key caps can be associated with a low, or very low, switch actuation latency period or duration, for example a switch actuation latency period or duration of less than approximately 2 ms, 1 ms, 0.5 ms, or less. 
     In addition, multiple embodiments of the present disclosure provide an ability to configure and/or position the main link and/or protrusion relative to the key cap in a manner such that the area of the viewing window is maximized. This is to say, the protrusion and/or main link can be configured and/or positioned to minimize obstruction or blockage of light transmitted through the light permeable region or surface. 
     Representative aspects of key switch mechanism, in particular key caps that are configured to provide tactile feedback upon user-effectuated actuation or displacement of said key caps, are described in detail hereinafter with reference to the drawings in which like or analogous elements or process portions are shown numbered with like or analogous reference numerals. 
     Key Switch Mechanism 
       FIG. 1A  shows a key switch mechanism  10  in accordance with several embodiments of this disclosure. The key switch mechanism  10  can constitute a part of a keyboard or keypad. As understood by a person of ordinary skill in the art, a keyboard or keypad is commonly used for human interaction with computers. For instance, a keyboard or keypad can be used as part of a gaming experience. Accordingly, the keyboard or keypad can be formed from a plurality of key switch mechanism  10 . In other words, a keyboard or keypad is made or constructed from more than one of the key switch mechanisms  10 . 
     The key switch mechanism  10  comprises a key cap  100 , a circuit module  200  and a linking mechanism  300  comprising a positioning board  350  and a set of main links  400 . The positioning board  350  has a top side  352  and a bottom side  354  opposite the top side  352 . For simplicity and to aid understanding,  FIG. 1A  illustrates the spatial orientation of the key switch mechanism  10 . The key switch mechanism  10  has a top side  12  and a bottom side  14  opposite the top side  12 . In many embodiments, the top side  12  and the bottom side  14  are substantially planar. 
     The key switch mechanism  10  of this disclosure provides a tactile feedback to a user upon user-effectuated, user-controlled or user-directed actuation or displacement of said key cap  100 . In many embodiments, the key switch mechanism  10  can be configured to provide a resistive force or resistance associated with displacement of the key cap  100 . The key cap  100  includes a protrusion or actuator  130  for activation of electrical signals. The key cap  100  includes a light permeable portion  150 . 
     The circuit module  200  comprises electronic circuitry  210 , a base  220 , an opening  230  and a corresponding actuator  240  coupled to a switch  242 . The electronic circuitry  210  is disposed on the base  220  and is configured to provide or produce electrical signals when activated. In many embodiments, the electronic circuitry  210  is electrically coupled to a computing device for signal communication therewith. The actuator  240  is electrically coupled to the electronic circuitry  210  by way of the switch  242 . By having an opening  230  on the base  220 , the key switch mechanism  10  can be placed over a display screen  250 . The display screen  250  is dynamic in that the images on the display screen  250  can be changed periodically or in response to user inputs. In many embodiments, the opening  230  is shaped and dimensioned such that the images on the display screen  250  are viewable through the opening  230 . Having the light permeable portion  150 , the key cap  100  allows a portion of the images on the display screen  250  to be viewable. 
     When in operation, the key switch mechanism  10  is orientated such that the top side  12  includes the positioning board  350  and the bottom side  14  includes the base  220 . As shown in  FIG. 1A , the positioning board  350  defines an aperture  356  shaped and dimensioned for receiving the corresponding key cap  100  therethrough. At least one clasp  360  is removably coupled to the positioning board  350 . The set of main links  400  is removably coupled to the at least one clasp  360 . 
       FIG. 1B  shows a 2-dimensional view of the key switch mechanism  10  on a first plane  16 . The base  220  is spatially displaced away from the positioning board  350  for accommodating any mechanism or parts of the key cap  100 . The positioning board  350  defines an aperture  356  shaped and dimensioned for receiving the key cap  100 . The aperture  356  is aligned with the opening  230  of the circuit module  200  such that images can be viewed through the key cap  100  by way of the light permeable portion  150 . In many embodiments, each key cap  100  functions in conjunction with a corresponding opening  230 . Each key cap  100  abuts a portion of the actuator  240  of the circuit module  200 . When the actuator  240  is activated (i.e depressed), electrical signals are communicated to which may result in transmission of signals. As will be further discussed later, displacement of the key cap  100  displaces the protrusion  130  against the actuator  240  to activate a corresponding electrical signal by depressing (activating) the actuator  240 . Displacement of the key cap  100  is along a travel axis  18  which is perpendicular or normal to the planar surface of the top side  12 . The key cap  100  is pivotably displaced along the travel axis  18 . 
     Aspects of Key Caps 
       FIGS. 2A and 2B  show a key cap structure  100  according to some embodiments of this disclosure. For simplicity, the key cap structure  100  is referred to as a key cap  100 . Specifically,  FIG. 2A  is a plan view and  FIG. 2B  is a perspective view of the key cap  100 . According to various aspects of this disclosure, the key cap  100  includes a top portion  102  and a bottom portion  104  opposite the top portion  102 . In many embodiments, the top portion  102  and the bottom portion  104  is a planar surface. 
       FIG. 2A  illustrates spatial orientations defined with respect to embodiments of this disclosure. The following describes the key cap  100  having sides or edges. For simplicity, each side or edge of the key cap  100  will be referred to as a side. In some embodiments, the key cap  100  has a first side  106 , a second side  108  which is disposed opposite the first side  106 , and a third side  110  and a fourth side  112  extending between the first side  106  and the second side  108 . The first side  106  is substantially perpendicular to the third side  110  and the fourth side  112 . Accordingly, the second side  108  is perpendicular to the third side  110  and the fourth side  112 . The spatial orientation of the top portion  102  is analogous to that of the bottom portion  104 . Accordingly, the following description relating to the spatial orientation of each of the first, second, third and fourth sides applies to the bottom portion  104 . 
     Each of the first side  106 , second side  108 , third side  110  and fourth side  112  has a corresponding wall extending therefrom the top portion  102  and the bottom portion  104  such that the first side  106 , the second side  108 , the third side  110 , the fourth side  112  and their respective walls extending therefrom, the top portion  102  and the bottom portion  104  form a cube or a cube-like structure. To facilitate understanding and for simplicity, the wall extending from the first side  106  is referred to as a first wall  114 , the wall extending from the second side  108  is referred to as the second wall  116 , the wall extending from the third side  110  is referred to as the third wall  118  and the wall extending from the fourth side  112  is referred to as the fourth wall  120 . The size of the key cap  100  can vary according to design specifications and user requirements. 
     To facilitate displacement of the key cap  100 , a set of main links  400  is coupled to the key cap  100 . In many embodiments, the key cap  100  defines at least one aperture  160  in the third wall  118  and at least one aperture  160  on the fourth wall  120 . The apertures in the third wall  118  and the fourth wall  120  are aligned such that the set of main links  400  are held or secured in place. The apertures  160  are formed on the exterior of the third wall  118  and fourth wall  120  for pivotably coupling the set of main links  400 . In some embodiments, a recess or depression is formed in place of the aperture  160 , where the recess has sufficient depth to engage and/or pivot the set of main links  400 . 
     The key cap  100  comprises a protrusion  130 . In many embodiments, the protrusion  130  of each key cap  100  extends from a periphery or perimeter of the key cap  100 , for example from an edge or corner of the key cap  100 . For space efficiency, the protrusion  130  is dimensionally smaller than the key cap  100 . In several embodiments, the protrusion  130  is of micro-range dimensions. In various embodiments, the key cap  100  comprises a protrusion  130  extending from the first wall  114  away from the interior thereof. The purpose of the protrusion  130  will be discussed further below. As will be understood by a person of ordinary skill in the art, the key cap  100  is activated when depressed or displaced from a first position to a second position about the first axis  18  which is perpendicular or normal to the planar surface of the top side  102 . In various embodiments, the displacement of the key cap  100  facilitates or effectuates a corresponding displacement of the protrusion  130  for contacting at least one actuator  230  of the circuit module  200 . 
       FIG. 2C  shows a key cap  100  being positioned relative to a circuit module  200  comprising an electronic circuitry  210 . The circuit module  200  includes an opening  230  in the base  220 . In many embodiments, the circuit module  200  functions in conjunction with the display screen  250 . The key switch mechanism  10  or circuit module  200  can be placed over the display screen  250  such that the images displayed by the display screen  250  are viewable through the opening  230 . Description of the circuit module  200  is discussed below. In many embodiments, the key cap  100  is optically transmissive. The key cap  100  can include an optically transmissive or light permeable surface, region, portion, or area  150  that is configured to allow light transmission therethrough. The light permeable surface, region, portion or area  150  can be referred to as a view area or viewing window. The key cap  100  can be coupled to, disposed on, carried by, placed onto, or positioned or disposed relative to, an opening  230 . By doing so, the images displayed by the display screen  250  can be projected or transmitted through the light permeable portion  150  of the key cap  100 . The light permeable portion or surface  150  of the key cap  100  has a periphery that frames the light permeable portion or surface  150 . Portions or areas of the display screen  250  can be viewed or seen through corresponding light permeable portion  150  of the key cap  100 . The key cap  100  described in this disclosure is an optically transmissive tactile key. 
     Being optically transmissive, the key cap  100  facilitates light and/or light images (not shown) from the display screen  250  to permeate, filter and/or spread through the key cap  100 . In many embodiments, the light permeable portion  150  includes at least 50% of the total area of the top portion  102  of the key cap  100 . In some other embodiments, 100% of the total area of the top portion  102  of the key cap  100  is optically transmissive. In yet some other embodiments, at least a portion of at least one of the first wall  114 , the second wall  116 , the third wall  118  and the fourth wall  120  is optically transmissive. 
     In multiple embodiments, the protrusion  130  is shaped, dimensioned, and/or configured for minimizing obstruction or blockage of light transmission through the light permeable region  150  of the key cap  100 . The position of the protrusion  130  at a periphery of, or even away from or external to, the key cap  100  can minimize, reduce, or prevent obstruction or blockage of light transmission through the light permeable region  150  of the key cap  100 . 
     The foregoing discussion describes the structure, outlook and/or architecture of a key cap  100 . It should be understood by a person of ordinary skill in the art that dependable upon design specifications, more than one key cap  100  can be deployed. This is illustrated in  FIG. 2D . 
       FIG. 2D  shows a schematic illustration of a key switch mechanism  10  that includes a plurality of optically transmissible tactile key caps  100 . The optically transmissible tactile key caps  100  are coupled to, carried by, or disposed relative to a corresponding display screen  250  that is carried by, or incorporated into, the circuit module  200 . 
     In embodiments wherein there is a plurality of key caps  100  coupled to, carried by, or disposed relative to a corresponding display screen  250 , multiple portions or areas of the display screen  250  can be viewed or seen through corresponding multiple light permeable regions  150  of the key cap  100 . 
     The key caps  100  of various embodiments supports rapid consecutive actuations or displacements (e.g., at least 50, 100, 150, or more actuations or displacements per minute) thereof for contacting corresponding actuators  240  (e.g., electromechanical switches) and generating electrical signals transmissible to the computing device. This means that the key caps  100  can be associated with a low, or very low, switch actuation latency period or duration, for example a switch actuation latency period or duration of less than approximately 2 ms, 1 ms, 0.5 ms, or less. 
     Aspects of the Circuit Module 
       FIG. 3A  shows a plan view of a base  220  of a circuit module  200  according to various aspects of this disclosure. The base  220  defines an opening  230  and the opening  230  includes a corresponding switch  242 . An electronic circuitry  210  is disposed on the base  220 . Although the description relates to a base  220  with an opening  230  and its corresponding switch  242 , it should be understood by a person of ordinary skill in the art that a base  220  can comprise a plurality of openings  230  (i.e two or more openings) with corresponding switches  242 . 
     The opening  230  is shaped and dimensioned such that the images from a display screen  250  can be projected or transmitted through the opening  230 . The display screen  250  includes one of a rigid display surface, for example an LCD or LED based display surface, and a flexible display surface, for example a polymer based display surface that is configured as an organic LED (OLED) surface. In many embodiments, the display screen  250  is referred to as an optical display surface or screen. The display screen  250  (e.g., LCD screen) is configured to dynamically display images (e.g., icons, figures, and alphanumeric characters). The display screen  250 , or specific portions, areas, or regions of the display surface or screen  250 , can be configured to variably display images at specific, predetermined, or different time intervals. In several embodiments, the display screen  250  is coupled to a computing system that is configured to execute stored program instructions corresponding to one or more application programs. The display screen  250  can dynamically illustrate or display images. For example, the display screen  250  can be refreshed in accordance to execution of one or more portions of the program instructions. When an electronic gaming software is executed, the display screen  250  can alter in response to user inputs. 
     Accordingly, the display screen  250  can be configured to variably display images depending upon one or more application programs. In several embodiments, the visual information (e.g., images, icons, text, and optical signals) displayed at different portions, regions, or areas of the display screen  250  can be dependent upon executed application program(s). The foregoing disclosure describes a key cap  100  working in conjunction with a display screen  250 . It should be understood that for a key switch mechanism  10 , more than one key cap  100  can be present. In many embodiments, a key cap  100  is coupled with a corresponding display screen  250 . 
       FIG. 3B  shows a perspective view of a key cap  100  with a circuit module  200  comprising an opening  230  with a corresponding actuator  240 . The protrusion  130  of the key cap  100  abuts the actuator  240 . The opening  230  is positioned over the display screen  250  such that at least a portion of the images of the display screen  250  can be projected or transmitted through the opening  230 . In several embodiments, the top portion  102  of the key cap  100  can be configured and/or positioned such that it can be disposed or positioned parallel, or substantially parallel, to the opening  230 . By doing so, users of the key switch mechanism  10  can clearly see the images displayed by the display screen  250 . The field of view defined by the key cap  100  and the light permeable portion is unblocked by the opening  230 . In many embodiments, the actuator  240  is in contact with or coupled to a switch  242 . The switch  242  is then electrically coupled to an electronic circuitry  210  of the circuit module  200 . 
       FIG. 3C  shows a cross sectional side view of a key cap  100  with a circuit module  200  in a first position (released position) and  FIG. 3D  shows a side view of a key cap  100  with a circuit module  200  in a second position (depressed position) according to various aspects of this disclosure. The actuator  240  is coupled to a switch  242  which is then electrically coupled to the electronic circuitry  210  of the circuit module  200 . Materials for the actuator  240  include elastomeric materials such as rubber. The actuator  240  can be one of a rubber dome, a metal dome, a leaf spring, a coil spring and an elastomeric structure. In many embodiments, the circuit module  200 , in particular, the actuator  240  bias the key cap  100  towards the released position (first position) and generates a control signal when the key cap  100  is displaced to the depressed position (second position). Actuator  240  is further shaped for conveying a tactile ‘click’ response to a user when being depressed or actuated. 
     The key cap  100  of embodiments of the present disclosure includes, incorporates, carries, or is couplable to the actuator  240 . The actuator  240  is then coupled to a switch  242 , which is in turn electrically coupled to the electronic circuitry  210  of the circuit module  200 . In many embodiments of this disclosure, each key cap  100  has a corresponding actuator  240 . Each actuator  240  enables, facilitates or activates a corresponding electrical signal by way of the switch  242 . The actuator  240  can be a electromechanical switch actuator or electromechanical contact element. For purposes of clarity, the actuator  240  will be described in portions of the following description as the electromechanical switch actuator or electromechanical contact element. As the actuator  240  is coupled to the electrical circuitry  210  by way of the switch  242 , contact between the protrusion  130  of the key cap  100  and the actuator  240  can activate the actuator  240  and trigger generation of electrical signal(s). Many embodiments of the present disclosure provide key caps  100  that include, incorporate, or are couplable to the protrusion  130 . The key cap  100  is displaceable for correspondingly displacing the protrusion  130  to thereby effectuate contact between the protrusion  130  and at least one actuator  240 . The key cap  100  is also configured to provide a tactile feedback to a user associated with, or during, user-effectuated displacement of the key cap  100  and corresponding displacement of the protrusion  130 . 
     The key cap  100  can be displaced relative to the opening  230  or display screen  250 , for example between at least a first position and a second position relative to the opening  230  or the display screen  250 . The second position can be located in closer proximity to the opening  230 . In other words, the first position is a default position where the key cap is not depressed or activated and the second position is where the key cap  100  is in a depressed position. Accordingly, the key cap  100  is displaceable to various distances relative to the opening  230 . Force (e.g., a user-controlled or user-effectuated force) applied to the key cap  100  can facilitate, or effectuate displacement of the key cap  100  instance to or towards the opening  230  (e.g., from the first position to or towards the second position relative to the display screen  250 ). Displacement of the key cap  100  (e.g., from the first position to, or towards, the second position) can be controlled or effectuated by a user. The resistive force provided by the key cap  100  in association with, upon, or during user-controlled or user-effectuated displacement of the key cap  100  from the first position to, or towards, the second position provides the user with a tactile feedback that is associated with the key cap  100  displacement. This tactile feedback associated with key cap  100  displacement or movement gives or provides the user with a measure of confirmation or knowledge of user&#39;s input, more specifically user-effectuated actuation or displacement of the key cap  100 . The tactile feedback is facilitated by way of a linking mechanism which will be discussed later. The actuator  240  is also for biasing the key cap  100  towards the released position (first position). For example, when the key cap  100  is depressed (second position), the actuator  240  can act as a spring to bias or actuate the key cap  100  towards the released position (first position). In some embodiments, the circuit module  200  can comprise a magnetic structure  260  for repelling the key cap  100  away from the second position to thereby bias the key cap  100  towards the first position. 
     As discussed above, the ability for light transmission through the light permeable region  150  allows images displayed on the display screen  250  to be seen or viewed via an opening  230  by a user. More specifically, an area or portion of the display screen  250  that corresponds to (e.g., is located or disposed directly underneath) said light permeable portion, area, or surface  150  of the key cap  100  can be viewed by the user. The display screen  250  is configured to output variable images (or optical signals), for instance depending upon application program(s) executed by a computing system coupled to the display screen. Such variable images (or optical signals) output by the display screen  250  can be transmitted through the light permeable region, portion, area, or surface  150  of the key cap  100 . 
     The light permeable region or surface  150  of the key cap  100  can be shaped, dimensioned, and/or configured to increase or maximize an area that allows light transmission through the key cap  100 . Increasing the area of the light transmissible region  150  can result in, or provide, a larger area of the key cap  100  through which a user is able to view images displayed by the display screen  250 . 
     As discussed in the foregoing disclosure, a plurality of key caps  100  can be present and for such configurations, there will be a corresponding opening  230  for each key cap  100 . 
     The images displayed on display screen  250  are dynamically changeable or variable, for instance depending upon gaming-related scenarios occurring on a computing device (e.g., desktop or laptop computer) to which the display screen  250  is coupled to and/or based upon prior user&#39;s inputs, actuations, or selections. The display screen  250  can include or be coupled to a memory or a memory storage unit as well as appropriate display screen circuitry to facilitate or enable static and/or dynamic presentation of image data by portion(s) of the display screen  250 . Image data (e.g., optical signals) output or displayed by the display screen  250 , or selected portions of the display screen  250 , can be selected and/or varied depending upon a set of programming instructions (e.g., corresponding to an application program, a set of device drivers, and/or firmware). 
     Positioning Board 
       FIGS. 4A and 4B  show a positioning board  350  with a key cap  100  according to various embodiments of this disclosure.  FIG. 4A  is a plan view and  FIG. 4B  is a side view of the positioning board  350  with a key cap  100 . The positioning board  350  has a top side  352  and a bottom side  354  facing away from the top side  352 . Both the top side  352  and the bottom side  354  are substantially planar. The positioning board  350  can be made of at least one of polycarbonate and plastic and can have a thickness of approximately between 5 and 10 mm. 
     The positioning board  350  is adapted to carry or support the key cap  100 . In many embodiments, the positioning board  350  is spatially displaced from the circuit module  200 . The positioning board  350  serves to keep the key caps  100  in their respective positions. This can be achieved by at least one clasp  360  to pivotably hold a set of main links  400  coupled to a key cap  100  in place. In many embodiments, the at least one clasp  360  is removably coupled to the bottom side  354 . This will be discussed further later. The positioning board  350  defines an aperture  356  which is shaped and dimensioned for receiving the key cap  100  therethrough. Depending upon embodiment details, the positioning board  350  can include a plurality of apertures  356 . Each of the plurality of apertures  356  is shaped and dimensioned for receiving a corresponding key cap  100  therethrough. For ease of understanding and to facilitate further discussion, a positioning board  350  with each aperture  356  shaped and dimensioned for receiving a single key cap  100  is referred to as a first configuration. 
     As will be understood by a person of ordinary skill in the art, the key cap  100  can protrude through a corresponding aperture  356  with the top side  102  of the key cap  100  protruding above the top side  352  of the positioning board  350 . By protruding the key cap  100  above the top side  352  of the positioning board  350 , a user of the key switch mechanism  10  can easily depress the key cap  100 . Further, the feedback experience enhances the overall gaming experience for the user. To facilitate easy depression of the key cap  100 , the aperture  356  is dimensioned bigger than the corresponding key cap  100  such that a void  358  exists between the aperture  356  and the corresponding key cap  100 . The void  358  can be between approximately 1-5 mm. In some embodiments, the top side  102  of the key cap  100  can be flushed with or below the top side  352  of the positioning board  350 . 
       FIG. 4C  shows an embodiment of the positioning board  350  of this disclosure. The positioning board  350  defines an aperture  356  which is shaped and dimensioned for receiving two key caps  100 . As will be understood by a person of ordinary skill in the art, the aperture  356  can be shaped and dimensioned to receive a plurality of key caps (i.e more than 2 key caps). Depending upon embodiment details, a positioning board  350  can have a combination of apertures  356  for single key caps  100  and apertures for a plurality of key caps  100 . For ease of understanding and to facilitate further discussion, a positioning board  350  with apertures  356  shaped and dimensioned for receiving a plurality of key caps  100  is referred to as a second configuration. 
       FIG. 4D  is a diagram of the at least one clasp  360  according to various embodiments of this disclosure. The at least one clasp  360  extends from the bottom side  354  of the positioning board  350 . The clasp  360  includes two arms  362  projecting away from the bottom side  354 . Each of the arms  362  is identical. Each arm  362  has an inner surface  364  facing away from an outer surface  366  and each arm defines at least one secure portion  368  on the inner surface  364  which is shaped and dimensioned to receive the set of links  400 . For simplicity, the space formed by the secure portion  368  is referred to as the secure space  370 . The secure space  370  is shaped and dimensioned such that it can firmly hold and secure a portion of the set of links  400 . In many embodiments, the two arms  362  can be shaped and dimensioned such that an opening  372  is defined. In many embodiments, the width of the opening  372  is smaller than that of the secure space  370 . By having an opening  372  smaller in width than the secure space  370 , the set of links  400  can be secured, held and/or positioned firmly by the clasp  360 . As will be described later, the secure space  370  facilitates the set of links  400  to pivot freely about the secure space  370 . 
     Linkage Mechanism 
       FIG. 5A  shows a plan view of the key cap  100  with the set of main links  400 . The set of main links  400  facilitates or is used for guiding travel of the key cap  100  substantially along the travel axis  18  between the depressed position (i.e second position) and the released position (i.e first position). The set of main links  400  is configured for substantially impeding tilt of the key cap  100  away from the travel axis  18  during travel of the key cap through the aperture  356  of the positioning board  350 . By way of the main link(s)  400 , the key cap  100  is configured to provide a resistive force or resistance to the displacement of the key cap  100  to, or towards, the display screen  250 , for example from the first position to, or towards, the second position. Accordingly, the key cap  100  is configured to provide a tactile feedback to a user upon, or associated with, a user-effectuated displacement of the key cap  100 . As discussed previously, the displacement of the key cap  100  can effectuate a corresponding displacement of the protrusion  130  of the key cap  100 . The protrusion  130  can be displaced to or towards a corresponding actuator  240  carried by, or disposed relative to, the display screen  250 . The actuator  240  is in contact or is coupled to a switch  242 . The switch  242  is in turn electrically coupled to the electronic circuitry  210  of the circuit module  200 . Said contact between the protrusion  130  and the switch  242  via the actuator  240  can result in generation of electrical signals, which is transmissible to a computing device and hence providing user input into said computing device. 
     In the following discussion, the orientation, position of the first position and the second position of the key cap  100  is analogous to that for  FIGS. 3C and 3D . The set of main links  400  is configured to provide a tactile feedback to a user upon user-controlled or user-effectuated displacement or actuation of the key cap  100 . The set of main links  400  can be configured and/or positioned to bias the key cap  100  at the first position and to provide a resistance or resistive force associated with a displacement of the key cap  100  from the first position to, or towards, the second position. The second position can be located at closer proximity to the display screen  250 . Accordingly, the set of main links  400  can be configured to provide a resistance or resistive force associated with displacement of the key cap  100  towards the display screen  250 . The set of main links can comprise one or more main links  402  (first main link, second main link etc). In embodiments where more than one main link  402  is used, the main links will be referred to as a first main, a second main link and so on. 
     The main link  402  can be shaped and dimensioned and/or configure to couple to the key cap  100  at or along a periphery of the key cap  100 , for example, at or along at least the first wall  114 , the second wall  116 , the third wall  118  or the fourth wall  120  of the key cap  100 . Further, the main link  402  can be shaped, dimensioned, and/or configured to couple to a number of walls of the key cap  100  such that the light permeable region  150  of the key cap  100  is located within, or substantially within, an area or perimeter defined by the main link  402 . The main link  402  can be configured and/or positioned in a manner that minimizes or reduces obstruction or blockage of light transmission through the light permeable region of the key cap  100 . 
     Essentially, the main link  402  is made of at least one of steel or other materials demonstrating similar elasticity and strength. For instance, the main link can be a rigid wire. The main link  402  has two ends, a first end  404  and a second end  406 , opposite the first end  404 . When the main link  402  is in use, the first end  404  substantially faces the second end  406 . The first end  404  and the second end  406  of the main link  402  is inserted into an aperture  160  defined in the third wall  118  and the fourth wall  120  of the key cap  100 . The diameter core of the main link  402  can be circle, square and hexangonal and can measure approximately between 1 and 2 mm. 
     In many embodiments, the main link  402  comprises a pivoting or medial portion  408  in between two support portions  410 . The pivoting portion  408  is pivotably mounted to the positioning board  350 . The pivoting portion  408  includes at least one secure portion  412  which is secured by the clasp  360  of the positioning board  350 . A pivot axis  414  is defined at, or through the pivoting portion  408  of the main link  402 . In many embodiments, the pivot portion  408  is located along the perimeter of the key cap  100  (i.e along the first wall  114  of the key cap  100 ). The secure portion  412  acts as a pivoting point along the pivot axis  414  where during movement of the key cap  100  from a first position to a second position or vice versa, the displacement of the key cap  100  from a first position to the second position is facilitated by the pivoting of the secure portion  412 . In some embodiments, the main link  402  comprises two or more separate portions. For instance, each secure portion  412  of each main link  402  is separate from another secure portion  412  of the same said main link  402 . 
     The pivoting portion  408  is located away from or external of the light permeable portion  150  of the key cap  100 . The location of the light permeable portion  150  away from the pivoting portion  408  minimizes or reduces obstruction caused by the pivoting portion  408  to light transmission through the light permeable region  150 . 
     User-effectuated displacement of the key cap  100  (e.g., by a user applied force onto the key cap  100 ) can facilitate or effectuate a corresponding displacement of the main link  402 , more specifically a pivot or rotation of at least a portion of the main link  402  about the pivot axis  414 . The key cap  100  can be pivoted or rotated about the pivot axis  414  upon user-effectuated displacement of the key cap  100 . The displacement, more specifically pivot or rotation, of the key cap  100  about the pivot axis  414  can effectuate displacement of the key cap  100  from the first position to or towards the second position. Displacement, more specifically pivot or rotation, of the key cap  100  from the first position to the second position can trigger or result in an actuation or activation of an actuator  240  that is coupled to, carried by, or disposed relative or adjacent to, the display screen  250 . 
     The actuator  240  is in contact or coupled to the switch  242  which is electrically coupled to the electronic circuitry  210  of the circuit module  200 . By displacing the key cap  100  to the second position, the protrusion  130  of the key cap  100  activates the switch  242  by way of the actuator  240 . In many embodiments, the displacement, more specifically pivot or rotation, of the key cap  100  displaces the protrusion  130  and effectuates contact between the protrusion  130  and the switch  242  by way of the actuator  240 . The actuator  240  is coupled to, carried by, or disposed relative or adjacent to, the display screen  250 . The contact between the  130  and the actuator  240  causes or triggers actuation of the switch  242  and thereby causes a generation of electrical signal(s) and transmission of generated electrical signal(s) to a computing device that is coupled to the switch  242 . 
       FIGS. 5B and 5C  show a side view of a key cap  100  in a first position being secured to the clasp  360  of the positioning board  350  by way of the main link(s)  402 . As shown in  FIGS. 5B and 5C , the protrusion  130  of the key cap  100  is being disposed between the clasp  360  and the actuator  240 . Depending upon embodiment details, each key cap  100  can be supported or secured by one or two main links  402 .  FIG. 5B  shows a side view of a key cap  100  where two main links  402  (a first main link and a second main link) are used and  FIG. 5C  shows a side view of a key cap  100  where a single main link  402  is used. It will be understood by a person of ordinary skill in the art that for a key cap  100  with one main link  402  ( FIG. 5C ), the first configuration (see description for  FIGS. 4A and 4B ) will be more suitable. For a key cap  100  with two main links  402  ( FIG. 5B ), the second configuration will be suitable as more support is provided by the second main link  402  to keep the key cap  100  in place. Analogous to the first main link, the second main link is pivotably coupled to the positioning board  350  and the exterior of the side wall of the key cap  100 . The first main link and the second main link being in a parallel configuration with the key cap  100  for further impeding tilt of the key cap  100  from the travel axis  18 . 
     The main links  402  are secured to the positioning board  350  by way of the clasp  360 . Each end of the main link(s)  402  is inserted into a corresponding aperture  160  of the key cap  100 . As shown in  FIG. 5B  each of the two main link(s)  402  is substantially parallel to each other. By having two main links  402 , the key cap  100  is firmly secured during displacement of the key cap  100  from the first position (released position) to the second position (depressed position). 
       FIG. 5D  is a side view of the key cap  100  of  FIG. 5B  in a second position. In a first position shown in  FIG. 5B , the main links  402  is substantially parallel to the third side  110  of the key cap  100 . When in the second position, each of the main links  402  is displaced at approximately 45 degrees towards the second position with respect to the first position. 
       FIG. 6A  shows key caps  100  of this disclosure arranged in a staggered array configuration. The set of main links  400  provides space efficiency in the arrangement of the key caps  100 . For instance, the set of main links  400  allows the key cap  100  to be arranged in a staggered array configuration which cannot be achieved in other key switch mechanism concepts such as a cantilever concept.  FIG. 6B  shows a cantilever key cap mechanism  500  which includes a key cap  502  and two arms  504 . As shown in  FIG. 6B , the two arms  504  extend outwards and away from the key cap  502 . A staggered array configuration is not operable with the cantilever key cap mechanism  500  as the arms may obstruct the other adjacent key caps. 
     Application of the Key Switch Mechanism 
     The key switch mechanism  10  according to several embodiments of this disclosure can be utilized in a number of ways. For instance, the key switch mechanism  10  can function as a key switch for a display. In some other applications, a plurality of key switch mechanism  10  can combine to form a keyboard or keypad. Alternatively, the key switch mechanism  10  can form part of a handheld device. 
     The key switch mechanism  10  and in particular, the circuit module  200  can be coupled to a computing system that includes a processor and a memory. The computing system is configured to execute stored program instructions corresponding to one or more application programs. Based upon application program execution, context, status or state, visual information (e.g., images, icons, text, and optical signals) can be generated or retrieved and directed to one or more portions, areas, or regions of the display screen  250 . For example, in a gaming environment where a gaming application is executed, visual information displayed at specific portions, areas, or regions of the display screen  250  can be dependent upon the execution, context, status, or state of the application program. 
     Thus, there has been shown and discussed various embodiments of a key switch mechanism which fulfils the objectives and advantages sought thereof. Many changes, modifications, variations, and other uses and applications of the subject disclosure will, however, become apparent to those skilled in the art after considering this specification together with the accompanying figures and claims. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the key switch mechanism of this disclosure are deemed to be covered by embodiments of this disclosure which is limited only by the claims which follows. 
     In the foregoing manner, various embodiments of the disclosure are described for addressing at least one of the foregoing disadvantages. Such embodiments are intended to be encompassed by the following claims, and are not to be limited to specific forms or arrangements of parts so described and it will be apparent to one skilled in the art in view of this disclosure that numerous changes and/or modification can be made, which are also intended to be encompassed by the following claims.