Patent Publication Number: US-2016231841-A1

Title: User interface

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 13/908,857, filed 3 Jun. 2013, which claims the benefit of U.S. Provisional Application No. 61/654,766, filed on 1 Jun. 2012, which is incorporated in its entirety by the reference. 
     This application is related to U.S. patent application Ser. No. 11/969,848, filed on 4 Jan. 2008, U.S. patent application Ser. No. 13/414,589, filed 7 Mar. 2012, U.S. patent application Ser. No. 13/456,010, filed 25 Apr. 2012, U.S. patent application Ser. No. 13/456,031, filed 25 Apr. 2012, U.S. patent application Ser. No. 13/465,737, filed 7 May 2012, and U.S. patent application Ser. No. 13/465,772, filed 7 May 2012, all of which are incorporated herein in their entireties by these references. 
    
    
     TECHNICAL FIELD 
     This invention relates generally to touch-sensitive displays, and more specifically to a new and useful user interface in the field of touch-sensitive displays. 
     BACKGROUND 
     Touch and interactive displays have become ubiquitous in consumer electronic devices, from cellular phones to tablets to personal music players, and this technology continues to spread into other devices, from watches to industrial equipment. However, these displays do not typically provide tactile guidance, thus requiring a user interacting with such a display to rely on visual guidance when providing an input. This can both inhibit user input speed and increase erroneous user inputs. Thus, there is a need in the field of touch-sensitive displays to create a new and useful user interface. This invention provides such a new and useful user interface. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIGS. 1A and 1B  are schematic representations of a user interface of the invention; 
         FIG. 2A-2F  are schematic representations in accordance with variations of the user interface; 
         FIGS. 3A and 3B  are schematic representations of one variation of the user interface; 
         FIG. 4  is a schematic representation of one variation of the user interface; 
         FIGS. 5A and 5B  are schematic representations of one variation of the user interface; 
         FIGS. 6A-6C  are graphical representations in accordance with variations of the user interface. 
         FIGS. 7A-7C  are schematic representations of variations of the user interface; 
         FIGS. 8A and 8B  are schematic representations of variations of the user interface; 
         FIG. 9  is a schematic representation of one variation of the user interface; 
         FIGS. 10A and 10B  are schematic elevation and plan representations, respectively, of one variation of the user interface; and 
         FIGS. 11A-11I  are a schematic representations of variations of the user interface. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The following description of the embodiment of the invention is not intended to limit the invention to these embodiments, but rather to enable any person skilled in the art to make and use this invention. 
     As shown in  FIGS. 1A and 1B , a user interface  100  includes: a substrate  110  defining a fluid channel  114  fluidly coupled to a cavity  112 , the fluid channel  114  including a linear segment  115  parallel to a first direction; a tactile layer  120  including a tactile surface  128 , a deformable region  122  cooperating with the substrate  110  to define the cavity  112 , and an peripheral region  124  coupled to the substrate no proximal a perimeter of the cavity  112 ; a displacement device  130  coupled to the fluid channel  114  and configured to displace fluid through the fluid channel  114  to transition the deformable region  122  from a retracted setting to an expanded setting, the tactile surface  128  at the deformable region  122  tactilely distinguishable from the tactile surface  128  at the peripheral region  124  in the expanded setting; a display  140  coupled to the substrate  110  and including a set of pixels  142  arranged in a linear pixel pattern parallel to a second direction, the second direction nonparallel with the first direction; and a sensor  150  coupled to the substrate no and configured to detect an input on the tactile surface  128 . 
     Similarly, as shown in  FIGS. 3A and 3B , a variation of the user interface  100  includes: a tactile layer  120  including a tactile surface  128 , a deformable region  122 , and an peripheral region  124  adjacent the deformable region  122 ; a substrate  110  coupled to the peripheral region  124  of the tactile layer  120 , including a support member  118  adjacent the deformable region  122  and configured to support the deformable region  122  against substantial inward deformation, defining a fluid channel  114  including a linear segment  115  parallel to a first direction, and defining a fluid conduit  116  configured to communicate fluid from the linear segment  115 , through the support member  118 , to the deformable region  122 ; a displacement device  130  configured to displace fluid through the fluid channel  114  to transition the deformable region  122  from a retracted setting to an expanded setting, the tactile surface  128  at the deformable region  122  tactilely distinguishable from the tactile surface  128  at the peripheral region  124  in the expanded setting; and a display  140  coupled to the substrate  110  and including a set of pixels  142  arranged in a linear pixel pattern parallel to a second direction, the second direction nonparallel with the first direction. 
     The user interface  100  defines a deformable region  122  that changes shape and/or vertical position between a retracted setting and an expanded setting to create tactilely distinguishable formations on a tactile surface  128 . The user interface  100  thus features tactilely dynamic characteristics controlled through a displacement device  130  that displaces fluid into and out of a cavity  112 , via a fluid channel  114 , to transition the deformable region  122  between vertical positions flush, above, and/or below the peripheral region  124 . The user interface  100  also includes a display  140  that outputs light, in the form of an image, through the substrate  110  and the tactile layer  120 . The fluid channel  114  and fluid contained therein may locally optically distort such an image passing through the substrate. For example, the fluid may optically distort (e.g., magnify) adjacent subpixels of one single color or an adjacent pixel gap, and a fluid channel  114  interface may obscure adjacent subpixels of another single color. However, a particular arrangement of the fluid channel  114  (i.e., the linear segment  115 ) relative to the linear pixel pattern of the display  140  may minimize perceived optical distortion of light output from the display  140  (e.g., preferential distortion of a particular subpixel color), such as in comparison with a fluid channel segment that is parallel or substantially parallel to a linear pixel pattern of a display. For example, nonparallel arrangement of the fluid channel  114  relative to the linear pixel pattern of the display  140  can yield substantially equivalent distortion of light output from all subpixel colors, thereby substantially minimizing perceived local optical distortion of a displayed image and substantially “camouflaging” the linear segment  115  of the fluid channel  114  for a user at a typical viewing distance (e.g., twelve inches between a user&#39;s eyes and the display  140 ). 
     Generally, the linear segment  115  is linear in a first direction that defines an acute (or obtuse) angle with the second direction that is parallel to the linear pixel pattern of the display  140 , as shown in  FIG. 6C . This arrangement can substantially minimize reflection, refraction, diffraction, and/or scattering effects of light emitted from multiple pixels or subpixels of various colors adjacent an edge of the linear segment  115 , thereby minimizing perceived optical distortion of light output from the display  140 . The arrangement can similarly minimize distortion of light emitted from multiple pixels or subpixels of various colors along and/or across the linear segment  115 . This can reduce the ease with which a user may optically resolve (i.e., notice visually) the linear segment  115  when an image is rendered on the display  140 . 
     The display  140  of the user interface  100  is coupled to the substrate no and includes the set of pixels  142  repeated along the second direction, thereby defining the linear pixel pattern along the second that is nonparallel with the first direction. The display  140  can be an in-plane-switching (IPS) LED-backlit color LCD display, a thin-film transistor liquid crystal display (TFT-LCD), an LED display, a plasma display, a cathode ray tube (CRT) display, an organic LED (OLED) display, or other type of display. The display  140  can also or alternatively incorporate any other type of light source, such as an OLED, cold cathode fluorescent lamp, hot cathode fluorescent lamp, external electrode fluorescent lamp, electroluminescent panel, incandescent panel, or any other suitable light source. Furthermore, the display  140  can incorporate plane-to-line switching, twisted nematic (TN), advanced fringe field switching (AFFS), multi-domain vertical alignment (MVA), patterned vertical alignment (PVA), advanced super view (ASV), or any other suitable switching technique. 
     Each pixel  142  in the display  140  can include a set of red, green, and blue (RGB) subpixels, though each pixel  142  can additionally or alternatively include a white (W) subpixel or a subpixel of any other color. For example, each pixel in the set of pixels  142  can include a set of color subpixels, wherein each color subpixel in the set of color subpixels is configured to output a discrete color of light (i.e., filter light output from a backlight). Each pixel in the display  140  can be identical in subpixel composition and arrangement, though the display can alternatively include multiple different types of pixels with different subpixel compositions and arrangements. The pixels can be patterned across the display  140  in a pixel pattern that is linear in at least the second direction. The pixels can also be patterned (i.e., repeated) along a third (linear) direction, such as perpendicular to the second direction to form a rectilinear pixel array as shown in  FIGS. 2A-2F . As shown in  FIGS. 2A, 2B, 2C, and 2F , the arrangement of subpixels within each pixel  142  can yield a display with uninterrupted alignment of same-color subpixels in at least one direction for vertically- and horizontally-patterned pixels. In one example shown in  FIG. 2A , arrangement of subpixels within each pixel can yield a display with uninterrupted vertical alignment of red subpixels. In another example shown in  FIGS. 2D and 2E , arrangement of subpixels within each pixel can yield a display with off-axis repetition of subpixels even for a rectilinear pixel array. In yet another example shown in  FIG. 2D , arrangement of subpixels within each pixel can yield a display with red subpixel repetition at approximately 60° from horizontal due to a rectilinear RGBW (red, green, blue, white) composition of each pixel. However, the pixels can be patterned in any other way and can include any other number and color subpixels in any other arrangement. The display  140  can also include pixels with same-color subpixels that repeat at any other angle, density, or distribution. 
     The display  140  can output an image aligned with the deformable region, as described in U.S. patent application Ser. No. 13/414,589, filed on 7 Mar. 2012, which is incorporated herein in its entirety by the reference. In one example, the display  140  can output a “swipe to unlock” image aligned with the deformable region that defines a linear elevated ridge in the expanded setting. In this example, the sensor can detect a swipe gesture along the raised linear ridge, and a processor coupled to the sensor can respond to the swipe gesture by “unlocking” an electronic device that includes the user interface  100 . However, the display can output any other image or portions of an image, and the sensor  150  and a processor can capture and respond to inputs adjacent various portions of the image in any other suitable way. 
     The substrate  110  of the user interface  100  defines the fluid channel  114  that is fluidly coupled to the cavity  112 , wherein the fluid channel  114  includes a linear segment  115  parallel to a first direction. The substrate  110  can be a translucent or transparent material, such as glass, chemically-strengthened alkali-aluminosilicate glass, polycarbonate, acrylic, polyvinyl chloride (PVC), glycol-modified polyethylene terephthalate (PETG), a silicone-based elastomer, urethane-based elastomers, allyl diglycol carbonate, cyclic olefin polymer, or any other suitable material or combination of materials. The substrate  110  can be substantially planar and substantially rigid, thereby retaining the tactile layer  120  at the peripheral region  124  in planar form. Alternatively, substrate  110  can be relatively extensible (and/or elastic, elastic, flexible, stretchable, or otherwise deformable) and mounted over the display  140 , wherein the display  140  is relatively rigid and retain the substrate  110  in planar form. However, the substrate  110  can be of any other form, such as curvilinear, convex, or concave. The tactile layer  120  can be joined, adhered, fastened, retained, or otherwise coupled across an outer broad face of substrate no, and the display  140  can be joined, bonded, adhered, fastened, retained, or otherwise coupled across an inner broad face of the substrate  110  opposite the outer broad face. (Hereinafter, ‘outer broad face’ may refer to the broad face of a component nearest the tactile surface  128 , and ‘inner broad face’ may refer to the broad face of a component furthest from the tactile surface  128 .) However, the inner broad face or outer broad face of the substrate no can alternatively be joined, bonded, adhered, fastened, retained, or otherwise coupled to a sensor  150 . For example, the sensor  150  can be arranged between the substrate no and the display  140  or between the substrate no and the tactile layer  120 . 
     The substrate no can fully enclose the fluid channel  114 . For example, the channel can be cut, machined, molded, formed, stamped, or etched into a first layer of the substrate no, and the first layer of the substrate no can be bonded to a second layer of the substrate no to enclose the channel and thus form the enclosed fluid channel  114 . Alternatively, a channel can be cut, machined, molded, formed, stamped or etched onto the inner broad face of the substrate  110  opposite the tactile layer  120 , and the display  140  or sensor  150  coupled to the inner broad face of the substrate no can cooperate with the substrate no to enclose the fluid channel  114 , as shown in  FIG. 8B . However, the substrate  114  can define the fluid channel  114  independently of or in cooperation with any other element. 
     The substrate  110  can also define the cavity  112  that is coupled to the fluid channel  114  and that is adjacent the tactile layer  120  at the deformable region  122 . The cavity  112  can communicate fluid from the fluid channel  114 , through a portion of the substrate no, to the inner broad face of the tactile layer  120  at the deformable region  122 . The cavity  112  can therefore communicate fluid pressure changes within the fluid channel  114  to the deformable region  122  to expand and retract the deformable region  122 . As shown in  FIG. 1A , the cavity  112  can be of a cross-sectional area greater than that of the fluid channel  114 . Alternatively, the cavity  112  can have a cross-sectional area that is less than that of the fluid channel  114 , or the fluid channel  114  can cooperate with a fluid conduit  116  to define the cavity  112 , as described below and shown in  FIG. 8B . As in the variation of the user interface  100 , the substrate no can alternatively define the cavity  112  that is in-line and/or continuous with the fluid channel  114 , such as of the same or similar cross-section as the fluid channel  114 . 
     The substrate  110  can additionally or alternatively define a support member  118  adjacent the deformable region  122  and configured to support the deformable region  122  against inward deformation in response to a force applied to the tactile surface  128  at the deformable region  122 . Generally, the support member  118  can define a hard stop for the tactile layer  120 , thus resisting inward deformation of the deformable region  122  due to a force (e.g., an input) applied to the tactile surface  128 . Alternatively, the support member  118  can define a soft stop that functions to augment a spring constant of the tactile layer  120  at the deformable region  122  once an input on the tactile surface  128  inwardly deforms the deformable region  122  onto the support member  118 . However, the support member  118  can function in any other way to resist substantial (inward) deformation of the tactile layer  128 . The support member  118  can be in-plane with the outer broad face of the substrate  110  adjacent the peripheral region  124  such that the member resists inward deformation of the deformable region  122  past the plane of the peripheral region  124 . However, the support member  118  can be of any other geometry or form. 
     In one implementation, the support member  118  defines a fluid conduit  116  that communicates fluid from the cavity  112 , through the support member  118 , to the inner broad face of the deformable region  122 . The fluid conduit  116  can be formed by etching, drilling, punching, stamping, molding, or forming, or through any other suitable manufacturing process. In this implementation, the support member  118  can define the fluid conduit  116  that is of a cross-sectional area less than that of a single pixel of the display  140 . However, the support member  118  can define the fluid conduit  116  that is of any other cross-sectional area, size, shape, or geometry. 
     In another implementation, the substrate defines the fluid conduit  116  configured to communicate fluid from the linear segment  115 , through the support member  118 , to the deformable region  122 , wherein the fluid conduit  116  and a portion of the linear segment  115  cooperate to define the cavity  112 , as shown in  FIGS. 3A, 3B , and  8 B. In this implementation, the fluid channel  114  can communicate fluid directly between the fluid conduit  116  and the displacement device  130  to transition the deformable region  122  between the retracted and expanded settings. 
     In yet another implementation, the substrate  110  defines the support member  118  that extends into the cavity  112  adjacent the deformable region  122 , as shown in  FIG. 1A . However, the substrate  110  can include any other component or feature, can be manufactured through any one or more processes, can be of any other form or geometry, and can include any number of fluid channels, cavities, and/or fluid conduits. 
     The fluid channel  114  includes the linear segment  115  that is linear in the first direction. The linear segment  115  can be of a rectilinear (shown in  FIGS. 8A ), trapezoidal, curvilinear, circular, semi-circular (shown in  FIG. 8B ), ovular, or elliptical cross-section or of any other suitable geometry or cross-section. For example, the fluid channel  114  can include multiple linear segments, as shown in  FIGS. 7A-7C , and the geometry and/or cross-section of each linear segment can be tailored to a local pixel geometry of the display  140  in order to substantially minimize perceived optical distortion of a portion of an image output by the display  140  and transmitted through the substrate  110  proximal the local linear segment. Furthermore, rather than sharp corners or edges, the linear segment  115  can include concave or convex fillets of constant or varying radii at various edges or corners. In this implementation, the fillets can minimize perceived optical distortion by softening otherwise sharp corners and edges. As shown in  FIG. 11A , the linear segment  115  can define parallel walls of a straight (e.g., linear) form. Alternatively, the linear segment  115  can be of varying width along and/or define an oscillatory profile along the first direction. In various examples, the linear segment  115  defines mirrored sinusoidal or wave-like walls (shown in  FIGS. 9, 11E, 11F, and 11H ), parallel sinusoidal or wave-like walls (shown in  FIG. 11B ), mirrored crenulated walls (shown in  FIG. 11I ), parallel crenulated walls (shown in  FIG. 11C ), or pseudorandomly-stepped walls (shown in  FIG. 11G ). In this implementation, a wall of the linear segment  115  can oscillate or vary in profile longitudinally and thus pass adjacent subpixels of different colors, and a varying-form wall of the linear segment  115  can thus limit preferential optical distortion of subpixels of one particular color over subpixels of another color within the display  140 . The linear segment  115  can also include one longitudinal edge that is straight and another defining a curvilinear geometry (as shown in  FIG. 11D ), though the linear segment  115  can define any other straight, varying, or oscillatory form. Therefore, as in the foregoing implementation, the linear segment  115  of the fluid channel  114  can be defined as a varying cross-sectional geometry swept linearly through the substrate  110  along (i.e., parallel to) the first direction, and a wall and/or edge of the linear segment  115  may be non-parallel to the first direction, parallel to the second direction, and/or parallel to the third direction. 
     The linear segment  115  can additionally or alternatively be of a substantially small cross-sectional area, such as relative to the size of a pixel or a thickness of the substrate. In this implementation, the minimal cross-section of the linear segment can limit perceived optical distortion of light at a boundary or interface, such as at a junction between the fluid and the fluid channel  114 . The cross-sectional geometry and/or the minimal cross-sectional area of the linear segment  115  can thus render the linear segment  115  substantially optically imperceptible to a user and/or limit perceived optical distortion of light transmitted from the display, such as to less than a just noticeable difference at a typical working distance of twelve inches between the display  140  and an eye of the user at a viewing angle of less than 10°. The linear segment  115  can also be substantially optically imperceptible to a user and/or feature perceived optical distortions less than a just noticeable difference at extended viewing angles, such as −75° to +75°, or at a particular viewing angle, such as 7°. 
     Fluid contained within the fluid channel  114 , the cavity  112 , and/or the fluid conduit  116  can be of a refractive index substantially similar to a refractive index of the substrate  110  and/or the tactile layer  120 , which can reduce perceived optical distortion at a junction between the fluid and the fluid channel and/or junction between the fluid and the tactile layer by limiting light refraction, reflection, diffraction, and/or scattering across the junction(s). For example, fluid contained within the fluid channel  114 , the cavity  112 , and the fluid conduit  116  can be selected for an average refractive index (i.e., across wavelengths of light in the visible spectrum) that is substantially identical to an average refractive index of the substrate  110  and/or of a chromatic dispersion similar to that of the substrate no. 
     As described above, features and geometries of the fluid channel  114 , the linear segment  115 , the cavity  112 , the substrate  110 , and/or the tactile layer  120  can limit light scattering, reflection, refraction, and diffraction of an image transmitted from the display  140  to a user. However, features and geometry of the foregoing components can additionally or alternatively limit directional or preferential light transmission or emission through the substrate no and/or the tactile layer  120  in favor of more uniform scattering, diffraction, reflection, and/or refraction of light through a portion of the substrate  110  and/or a portion of the tactile layer  120 . 
     The linear segment  115  of the fluid channel  114  can be defined as any of the foregoing cross-sectional geometries swept linearly through the substrate  110  parallel to the first direction. The linear segment  115  can also pass through the substrate  110  at substantially constant depth relative to the outer broad face of the substrate no, the first direction thus parallel to a plane of at least a portion of the outer broad face of the substrate  110 . However, the fluid channel  114  and/or the linear segment  115  can pass through the substrate  110  at varying, undulating, or stepped depths through the substrate. 
     Generally, as described above, the first direction is nonparallel with the second direction such that the linear segment  115  is misaligned with the linear pixel pattern. The linear segment  115  can also be misaligned with a subpixel pattern or subpixel color repetition within the display  140 . In one configuration of one example in which the display includes a linear pixel pattern in which same-color subpixels are adjacent, such as shown in  FIGS. 2A and 2B , the linear segment  115  is parallel with a series of same-color subpixels. In this configuration, an edge of the linear segment  115  (i.e., substrate/fluid boundary) can be aligned with a single subpixel of a particular color and thus selectively distort (e.g., magnify, non-uniformly disperse, etc.) a line of subpixels of the particular color. Furthermore, visual alignment of the linear segment  115  with a row of same-color pixels can be dependent on a user viewing angle, wherein a low viewing angle (e.g., &gt;10°) yields perceived optical distortion of a row of subpixels of one particular color (e.g., red), wherein an intermediate viewing angle (e.g., 10°-30°) yields perceived optical distortion of a row of subpixels of one particular color (e.g., green), and wherein a high viewing angle (e.g., &lt;30°) yields perceived optical distortion of a row of subpixels of yet another particular color (e.g., blue). In another configuration of this example, the linear segment  115  can be misaligned with the linear pixel pattern at a small included angle (e.g., less than 10° with the second direction). In this configuration, an edge of the linear segment  115  can align substantially with sets of linearly adjacent red, green, and blue subpixels, such as ten adjacent red pixels, followed by ten adjacent green pixels, followed by ten adjacent blue pixels, and repeating. In this configuration, the linear segment  115  can optically distort repeating sets of linearly adjacent subpixels, thus yielding selective perceived local optical distortion (e.g., magnification) of a particular subpixel color, which may be visually perceptible to a user at a typical viewing distance. 
     As an angle between the linear segment  115  and the linear pixel pattern increases, a length of each set of linearly adjacent red, green, and blue subpixels optically distorted by the linear segment  115  decreases to a minimum number of adjacent same-color subpixels (e.g., one). For example, for a subpixel arrangement shown in  FIG. 2A , when the first direction intersects the second direction at or near 60°, the linear segment  115  may equally optically distort each color in an adjacent red-green-blue subpixel pattern, thereby minimizing selection distortion of a particular subpixel color. For the subpixel arrangement shown in  FIGS. 2A and 2B , an ‘optimum’ angle between the first and second directions may be related to a length-to-width ratio of each pixel (or subpixel). In one example, for a square subpixel, the ‘optimum’ angle between the first and second directions can be 45°. In another example, for a subpixel with a height to width ratio of ˜1.7, the ‘optimum’ angle between the first and second directions can be ˜60° (i.e., tan (60°=1.732). However, for the display  140  that includes a set of rectilinear pixels in which each pixel defines a short face and a long face, the second direction can be parallel to the short face of the set of pixels, and the first direction can be parallel to a diagonal across the short face and the long face of each pixel in the set of pixels. 
     For pixels (and subpixels) patterned linearly across the display  140 , as the angle between the first and second directions approaches 90°, the linear segment  115  of the fluid channel can optically distort (e.g., magnify) a gap between pixels (or subpixels). Because the gap between pixels (or subpixels) is not lighted and may be colored black, white, or gray, the linear segment  115  may optically magnify or distort a black, white, or gray line on the screen in configurations in which the linear segment  115  is substantially parallel to a gap between pixels (or subpixels). Therefore, for the pixel configurations shown in  FIGS. 2A and 2   b,  for included angels between the first and second directions that substantially exceed 45°, black, white, and/or gray lengths may become optically visible along the linear segment. 
     In another implementation, the first direction can (equally) bisect the second direction and a third direction, wherein the second direction is parallel to the linear pixel pattern defined by nearest adjacent same-color subpixels, and wherein the second direction is parallel to a second linear pixel pattern defined by next-closest same-color subpixels. In this implementation, the linear segment  115  (via the first direction) can thus be substantially parallel to a pattern of subpixels defined by linearly adjacent different colors, such as a repeating pattern of red, green, and blue subpixels. This configuration can substantially minimize perceived preferential optical distortion of one or a subset of colors in each pixel. 
     In another example of the foregoing implementation, each pixel can include a two-by-two array of red, green, blue, and white subpixels, and a set of pixels  142  patterned longitudinally along one axis of the two-by-two array and patterned in a mirrored configuration laterally along another axis of the two-by-two array to define the display  140 , such as shown in  FIG. 2D . In this example, for subpixels that are substantially square, the second and third directions can be approximately 45° above and below the horizontal plane, each of the second and third directions thus parallel to nearest same-color subpixels. Therefore, in this example, the first direction can be parallel to horizontal and thus equally bisect the second and third directions. In this configuration, the linear segment  115  can thus be substantially parallel to a red, green, blue, and white repeated subpixel pattern, which may yield substantially minimal preferential distortion of one or a subset of colors of the display. 
     In yet another example of the foregoing implementation, each pixel can include a two-by-two array of red, green, blue, and white subpixels, and a set of pixels  142  patterned longitudinally and laterally along vertical and horizontal axes of the two-by-two arrays to define the display  140 , such as shown in  FIG. 2E . In this example, linear repetition of a first subset of adjacent color pixels (e.g., red and green) can occur along the second direction (e.g., parallel to horizontal), linear repetition of a second subset of adjacent color pixels (e.g., red and blue) can occur along the third direction (e.g., parallel to vertical), and linear repetition of a third subset of adjacent color pixels (e.g., red and white) can occur along a fourth direction (e.g., 60° above horizontal). Therefore, in this example, the first direction can be approximately 30° above horizontal, which bisects the second and fourth directions and is nonparallel the third direction. In this configuration, the linear segment  115  can thus be substantially parallel to a red, green, blue, and white repeated subpixel pattern, which may yield substantially minimal preferential distortion of one or a subset of colors of the display. 
     Therefore, in one example of the foregoing implementations shown in  FIG. 4 , wherein the display  140  includes pixels patterned in the second direction that is parallel to an X-axis and patterned in a third direction that is parallel to a Y-axis, the first direction bisects the second and third directions at 45°. In another example (similar to that shown in  FIG. 6B ), the display  140  includes pixels patterned in the second direction that is along an X-axis with subpixel repetition along a third direction that is 60° from the X-axis, and the first direction bisects the second and third directions at 30° from the X-axis. In another example shown in  FIG. 6A  (and similarly in  FIG. 4 ), the display  140  includes pixels patterned in the second direction that is along an X-axis and patterned in a third direction that is along a Y-axis, the sensor  150  includes electrodes patterned linearly in a fourth direction that bisects the second and third directions at 45° from the X-axis, and the first direction bisects the second and fourth directions at 22.5°. However, the linear segment  115  of the fluid channel  114  can cooperate with the linear pixel pattern and/or the linear sensor electrode pattern to define any other included angle. 
     As shown in  FIG. 4 , the substrate no can include multiple linear segments that define a serpentine fluid channel of a substantially rectilinear path. For example, the fluid channel  114  can include a set of parallel linear segments connected via perpendicular linear segments to define a serpentine fluid path. Each linear segment of the serpentine path can be orthogonal to an adjacent linear segment, as shown in  FIG. 7A . However, adjacent linear segments of the fluid channel  114  can form any other included angle (as shown in  FIG. 7C ) in order to maintain nonparallelism between each linear segment and a linear pixel pattern and/or a linear sensor electrode pattern throughout the user interface  100 . Alternatively, the substrate no can include linear segments that define any other structure or path, such as a tree-like arrangement of fluid channel segments. 
     As shown in  FIG. 7B , intersections of various linear segments can also be filleted to minimize perceived optical distortions, such as Fresnel reflections, that may occur at sharp junctions between materials, such as between a face of the fluid channel  114  and the fluid proximal a corner of the fluid channel  114 . However, the substrate no can define the fluid channel  114  that is of any other geometry and includes any other number of linear or nonlinear sections arranged in any other format or according to any other schema. 
     As shown in  FIGS. 10A and 10B , in one implementation in which the fluid channel  114  includes several closely-spaced adjacent linear segments of substantially small cross-section (e.g., an array of connected microfluidic channels), the fluid channel  114  can polarize light transmission and/or emission through the substrate  110 . Furthermore, due to pixel and/or subpixel arrangement, the display  140  can output polarized light such that orthogonal arrangement of the linear segments of the fluid channel to the linear pixel pattern may substantially obscure light transmission and/or emission through the substrate  110 . Therefore, in this implementation, linear segments of the fluid channel  114  can be arranged at substantially less than 90° to the linear pixel pattern. Generally, the linear segments of the fluid channel  114  can be arranged at an angle that sufficiently compromises selective local distortion of particular subpixel colors and internal light reflectance through polarization effects. For example, the first direction can intersect the second direction at 5°, thereby permitting 85% light transmission through the substrate proximal the fluid channel  114  with optically imperceptible linear segments at a viewing distance of twelve inches between −30° and +30° viewing angles. In another example, an angle of 45° between the first and second directions can permit 50% light transmission with optically imperceptible linear segments at a viewing distance of twelve inches between −60° and +60° viewing angles. However, the fluid channel  114  can include any other number of linear segments of any other size, spacing, or arrangement relative to the linear pixel pattern of the display  140 . Furthermore, the substrate  110  can define the fluid channel  114  relative to the display  140  to minimize directional polarization of light transmitted or emitted through the substrate  110  such that a perceived intensity of transmitted or emitted light does not substantially change as the user interface  100  is rotated relative to a user. 
     However, in other implementations, the first and second directions are substantially aligned such that the linear segment  115  and the linear pixel pattern of the display  140  are substantially parallel. In one implementation, the cross-section of the linear segment  115  can incorporate heavy filleting to avoid sharp corners. In another implementation, the fluid channel  114  includes nonlinear sections defining arcuate, elliptical, spline, Bezier, or any other nonlinear path through the substrate. 
     In yet other implementations, the substrate  110  can be physically coextensive with the display  140  and/or the sensor  150 . For example, the fluid channel  114  can be formed into an inner broad face of the tactile layer  120  or otherwise substantially defined on or within the tactile layer  120 . In this example, the cavity  112  can also be partially defined by a recess on the inner broad face of the tactile layer  120  at the deformable region  122 . In this example, the tactile layer  120  can be bonded or otherwise attached to the substrate  110  at the peripheral region  124 , which rigidly retains the peripheral region  124  as the deformable region  122  is transitioned between setting. However, the substrate  110 , cavity  112 , fluid channel  114 , etc. can be configured, arranged, and/or formed in any other suitable way. 
     The tactile layer  120  of the user interface  100  includes the tactile surface  128 , a deformable region  122  cooperating with the substrate  110  to define the cavity  112 , and a peripheral region  124  coupled to the substrate proximal a perimeter of the cavity  112 . As described in U.S. patent application Ser. No. 12/652,708, filed on 22 Mar. 2010, which is incorporated herein in its entirety by this reference, the tactile layer  120  can be selectively coupled (e.g., attached, adhered, mounted, fixed) to the substrate  110  at the peripheral region  124  such that the deformable region  122  can transition between vertical positions, relative to the peripheral region  124 , given a fluid pressure change within the fluid channel  114 . As described below, the displacement device  130  can manipulate fluid pressure within the cavity  112 , via the fluid channel  114 , to transition the deformable region  122  between vertical positions. The peripheral region  124  can be coupled to the outer broad face of the substrate no at an attachment point  126 , along an attachment line, or across an attachment area adjacent the perimeter of the cavity  112 . The peripheral region  124  of the tactile layer  120  can be coupled to the substrate  110  via gluing, bonding (e.g., diffusion bonding), surface activation, a mechanical fastener, or by any other suitable means, mechanism, or method. 
     The tactile layer  120  can be a translucent or substantially transparent material, thereby enabling transmission of light therethrough, such as from the display  140 . The tactile layer  120  can be of a single substantially extensible and/or elastic (and/or flexible, stretchable, or otherwise deformable) material across both the deformable region  122  and the peripheral region  124 . Alternatively, the tactile layer  120  can be selectively extensible and elastic, such as across all or a portion of the deformable region  122  or proximal a perimeter of the cavity  112 . The tactile layer  120  can also be of uniform thickness across the deformable and peripheral regions  122 ,  124 . However, the tactile layer  120  can be of any other form, thickness, material, elasticity, extensibility, or composition, etc. 
     As described above, one implementation includes a fluid conduit  116  that communicates fluid from the cavity  112 , through the support member  118 , to the inner broad face of the deformable region  122 , the thickness of the tactile layer  120  can be approximately equal to or greater than a (maximum cross-sectional) width of the fluid conduit  116 . In this configuration, the thickness of the tactile layer  120  at the deformable region  122  can thus limit excursion of the tactile layer  120  into the fluid conduit  116  in response to a force applied to the tactile surface  128 . Similarly, the thickness of the tactile layer  120  can be approximately equal to or greater than a maximum width dimension of the cavity  112  adjacent the inner broad face of the tactile layer  120 , which can similarly limit excursion of the tactile layer  120  into the cavity  112  in the presence of a force applied to the tactile surface  128 . 
     The tactile layer  120  can also be of non-uniform thickness across the deformable and peripheral regions  122 ,  124 . In one implementation, the deformable region  122  includes a column that extends into the cavity  112 , as shown in  FIGS. 5A and 5B  and described in U.S. patent application Ser. No. 13/481,676, filed on 25 May 2012, which is incorporated herein in its entirety by this reference. For example, the deformable region  122  can include a tapered column configured to seat on a tapered wall of the cavity  112 , such as in the retracted setting or when the deformable region is depressed, to support the tactile surface  128  at the deformable region  122  against inward deformation in response to a force applied to the tactile surface  128 . Thus, the cavity  112  can cooperate with the column to function as the support member  118  described above. 
     In another implementation, the deformable region  122  includes a reduced-cross-section portion along the perimeter of the cavity  112 , wherein the reduced-cross-section portion absorbs a substantial degree of deformation of the deformable region  122  when transitioned between the expanded and retracted settings. 
     The tactile surface  128  can be continuous across the deformable and peripheral regions  122 ,  124 , as shown in  FIG. 3A and 3B . The tactile layer  120  can be of a single material or a composition of multiple sublayers of the same or different materials. For example, the tactile layer  120  can include several sublayers of the same or different materials, such as a silicone elastomer sublayer bonded to a Poly(methyl methacrylate) (PMMA) sublayer. Alternatively, the tactile layer  120  can be of any one or more sheets or sublayers of polycarbonate, acrylic, polyvinyl chloride (PVC), or glycol-modified polyethylene terephthalate (PETG). However, the tactile layer  120  can be of any other geometry or material and can exhibit any other suitable optical, chemical, or mechanical property. 
     The displacement device  130  of the user interface  100  is coupled to the fluid channel  114  and is configured to displace fluid through the fluid channel  114  to transition the deformable region  122  from the retracted setting to the expanded setting, wherein the tactile surface  128  at the deformable region  122  is tactilely distinguishable from the tactile surface  128  at the peripheral region  124  in the retracted setting. Generally, the displacement device  130  functions to actively displace fluid through the fluid channel  114  and into the cavity  112  to outwardly expand the deformable region  122 , thereby raising the deformable region  122  relative to the peripheral region  124  and/or transitioning the deformable region  122  from the retracted setting to the expanded setting. The displacement device  130  can also actively remove fluid from the fluid channel  114  and the cavity  112  to inwardly retract the deformable region  122 , thereby lowering the deformable region  122  relative to the peripheral region  124  and/or transitioning the deformable region  122  from the expanded setting to the retracted setting. The displacement device  130  can further transition the deformable region  122  to one or more intermediate positions or height settings between the expanded and retracted settings. The tactile surface  128  at the deformable region  122  can be flush (e.g., planar) with the tactile surface  128  at the peripheral region  124  in the retracted setting, and the tactile surface  128  at the deformable region  122  can be offset vertically (i.e., elevated above or lowered below) from the tactile surface  128  at the peripheral region  124  in the expanded setting such that the expanded setting is tactilely distinguishable from the retracted setting at the tactile surface  128 . Alternatively, the tactile surface  128  at the deformable region  122  can be offset below the tactile surface  128  at the peripheral region  124  in the retracted setting, and the tactile surface  128  at the deformable region  122  can be flush with the tactile surface  128  at the peripheral region  124  in the expanded setting. However, the deformable region  122  can be positioned at any other height relative to the peripheral region  124  in the retracted and expanded settings. 
     The displacement device  130  can be an electrically-driven positive-displacement pump, such as a rotary, reciprocating, linear, or peristaltic pump powered by an electric motor. Alternatively, the displacement device  130  can be manually powered, such as though a manual input provided by the user, an electroosmotic pump, a magnetorheological pump, a microfluidic pump, or any other suitable device configured to displace fluid through the fluid channel  114 , the cavity  112 , and/or the fluid conduit  116 . For example, the displacement device  130  can be a displacement device described in U.S. Provisional Application No. 61/727,083, filed on 12 Dec. 2012, which is incorporated in its entirety by this reference. 
     One variation of the user interface  100  further includes a reservoir  132  configured to contain fluid. In one example, the reservoir  132  contains excess fluid, and the displacement device  130  displaces fluid from the reservoir  132  into the cavity  112 , via the fluid channel  114 , to transition the deformable region  122  from the retracted setting to the expanded setting. In this example, the displacement device  130  can further displace fluid from the cavity  112  into the reservoir  132 , via the fluid channel  114 , to transition the deformable region  122  from the expanded setting to the retracted setting. Furthermore, in this example, the displacement device  130  can include an electrically-powered, unidirectional, positive-displacement pump coupled to a series of bidirectional valves, wherein valve positions can be set in a first state to actively pump fluid from the reservoir  132  into the cavity  112 , and wherein valve positions can be set in a second state to actively pump fluid from the cavity  112  into the reservoir  132 . The reservoir  132  can be defined by a second cavity in the substrate  110 , or the reservoir  132  can be a discrete component integrated into an electronic device incorporating the user interface  100 , such as inside a housing of a mobile computing device. However, the reservoir  132  can be defined in any other suitable way and can be coupled to the displacement device  130  and to the fluid channel  114  in any other suitable way. 
     The sensor  150  of the user interface  100  is coupled to the substrate and configured to detect an input on the tactile surface  128 . The sensor  150  can be a capacitive touch sensor, a resistive touch sensor, an optical touch sensor, a fluid pressure sensor, an acoustic touch sensor, or any other suitable type of sensor, such as described in U.S. patent application Ser. No. 12/975,329, filed on 21 Dec. 2010, U.S. patent application Ser. No. 12/975,337, filed on 21 Dec. 2010, and U.S. Provisional Application No. 61/727,083, filed on 12 Dec. 2012, which are all incorporated in their entirety by this reference. 
     The sensor  150  can include a set of sensing elements configured to detect an input at particular regions across the tactile surface  128 , as described in U.S. Provisional Application No. P25, filed on ??, which is incorporated in its entirety by this reference. In one implementation described above, the sensor  150  can include a set of linear sensing elements patterned along a fourth direction, wherein the first direction is nonparallel with the second direction, the third direction, and the fourth direction, and wherein the second direction is nonparallel with the first direction, the third direction, and the fourth direction. For example, the sensor  150  can be a capacitive touch sensor including a set of electrodes arranged in a linear electrode pattern parallel to the fourth direction, as shown in  FIG. 4 . In this example, the second direction can be perpendicular to the third direction, the first and second directions can define an included angle of 30°, and the fourth and second directions can define an included angle of 60°. However, the sensor  150  can be of any other type, include any other feature, component, or sensing element, and can be patterned in any other suitable way and in any other suitable direction. 
     The sensor  150  can be arranged between the display  140  and the substrate  110 . Alternatively, the display  140  and the sensor  150  can cooperate to define a touch display (i.e., the display  140  and the sensor  150  can be physically coextensive). A portion of the sensor  150  can also be arranged within the cavity  112 , within a portion of the substrate  110  (e.g., above or below the fluid channel  114 ), or within a portion of the tactile layer  120 . However, all or a portion of the sensor  150  and/or one or more sensing elements of the sensor  150  can be arranged in any other way within the user interface  100 . 
     One variation of the user interface  100  includes a second deformable region that cooperates with the substrate  110  to define a second cavity, wherein the second cavity is coupled to a second fluid channel, and wherein the displacement device is coupled to the second fluid channel and is configured to displace fluid through the second fluid channel to transition the second deformable region between a retracted setting and an expanded settings. For example and as shown in  FIG. 4 , the deformable regions (i.e., the deformable region  122  and the second deformable region) can define discrete input regions when in the expanded settings, wherein each discrete input region is associated with one key of a QWERTY keyboard. In this example, the display  140  can output a first portion of an image aligned with the deformable region  122  and a second portion of the image aligned with the second deformable region, wherein the first portion of the image includes a visual representation associated with the deformable region  122  (e.g., SHIFT, ‘a,’ ‘g,’ or ‘8’), and wherein the second portion of the image includes a visual representation associated with the second deformable region. 
     Similarly, the tactile layer  120  can include a second deformable region cooperating with the substrate  110  to define a second cavity, wherein the fluid channel  114  defines a second linear segment perpendicular to the linear segment  115 . In this example, the second linear segment can be coupled to the linear segment  115  and to the second cavity, and the displacement device  130  can be further configured to displace fluid through the linear segment  115  and through the second linear segment to transition the deformable region  122  and the second deformable region from the retracted setting to the expanded setting, wherein the tactile surface  128  at the second deformable region is tactilely distinguishable from the tactile surface  128  at the peripheral region  124  in the expanded setting. In this example, in the expanded setting, the display  140  can output an image of an alphanumeric keyboard including a first image portion of a first key proximal the deformable region  122  and a second image portion of a second key proximal the second deformable region, wherein the first input key and the second input key are each a unique alphanumeric character of the alphanumeric keyboard. Furthermore, in this example, a processor coupled to the sensor  150  can distinguish an input on the tactile surface  128  at the deformable region  122  and an input on the tactile surface  128  at the second deformable region, thereby capturing serial alphanumeric inputs across expanded deformable regions of the tactile surface  128 . 
     One variation of the user interface  100  includes a processor  160  that handles an input detected on the tactile surface  128  by the sensor  150 . The processor  160  functions to handle (e.g., respond to) an input detected on the tactile surface  128 . In one implementation, the processor  160  is configured to identify an input of a first type and an input of a second type on the tactile surface  128  at the deformable region  122 , wherein the input of the first type is characterized by inward deformation less than a threshold magnitude, and wherein the input of the second type characterized by inward deformation greater than the threshold magnitude. For example, the threshold magnitude can be a threshold change in fluid pressure within the cavity, such as 0.5 psi (3450 Pa), or a threshold deformation distance, such as 0.025″ (0.64 mm). In one example implementation, when the deformable region  122  is in the expanded setting, the processor  160  identifies an input on the tactile surface  128  that substantially inwardly deforms the deformable region  122  as an input request for a capitalized alphabetical key associated with (e.g., displayed adjacent) the deformable region  122 , and the processor  160  identifies an input on the tactile surface  128  that does not substantially inwardly deform the deformable region  122  as an input request for a lower-cased alphabetical key associated with the deformable region  122 . 
     One implementation of the user interface  100  is incorporated into an electronic device. The electronic device can be any of an automotive console, a desktop computer, a laptop computer, a tablet computer, a television, a radio, a desk phone, a mobile phone, a PDA, a personal navigation device, a personal media player, a camera, a watch, a gaming controller, a light switch or lighting control box, cooking equipment, or any other suitable electronic device. 
     As a person skilled in the art will recognize from the previous detailed description and from the figures and claims, modifications and changes can be made to the embodiments of the invention without departing from the scope of this invention as defined in the following claims.