Keyless keyboard with force sensing and haptic feedback

Abstract

An input device for an electronic device includes an enclosure and a top member defining an input surface having multiple differentiated input regions. The input device further includes a first force sensing system associated with a first area of the top member and including a first group of the differentiated input regions, and a second force sensing system associated with a second area of the top member and including a second group of the differentiated input regions. The input device further includes a touch sensing system configured to determine which input region from the first group of the differentiated input regions corresponds to the first force input and to determine which input region from the second group of the differentiated input regions corresponds to the second force input.

What is claimed is: 
     
         1 . An input device for an electronic device, comprising:
 an enclosure;   a top member coupled to the enclosure and defining an input surface having multiple differentiated input regions;   a first force sensing system associated with a first area of the top member, the first area including a first group of the differentiated input regions and the first force sensing system configured to determine a first force associated with a first force input applied within the first area;   a second force sensing system associated with a second area of the top member, the second area including a second group of the differentiated input regions and the second force sensing system configured to determine a second force associated with a second force input applied within the second area; and   a touch sensing system configured to determine which input region from the first group of the differentiated input regions corresponds to the first force input and to determine which input region from the second group of the differentiated input regions corresponds to the second force input.   
     
     
         2 . The input device of  claim 1 , wherein:
 the multiple differentiated input regions correspond to keys of a keyboard;   the multiple differentiated input regions are visually differentiated on the top member;   the input device is configured to detect a key press of a particular input region by detecting, within a given group of the differentiated input regions, both a touch location and a force value satisfying a force threshold; and   the input device further comprises a haptic output system configured to produce a tactile output in response to detecting the key press.   
     
     
         3 . The input device of  claim 2 , wherein:
 the haptic output system comprises:
 a first actuator having a first actuation axis along a first direction; and 
 a second actuator having a second actuation axis along a second direction that is not parallel to the first direction; and 
   the input device is configured to alternate between actuating the first actuator and the second actuator in response to detecting successive key presses.   
     
     
         4 . The input device of  claim 1 , wherein the first force sensing system is configured to determine the first force independently of the second force sensing system. 
     
     
         5 . The input device of  claim 1 , wherein:
 the first group of the differentiated input regions corresponds to keys typically selected by a first finger of a user's hand; and   the second group of the differentiated input regions corresponds to keys typically selected by a second finger of the user's hand.   
     
     
         6 . The input device of  claim 1 , wherein:
 the first and the second force sensing systems are part of a group of force sensing systems; and   the group of force sensing systems defines two rows of force sensing regions on the top member.   
     
     
         7 . The input device of  claim 1 , wherein the first and second groups of the differentiated input regions are oriented substantially diagonally with respect to a longitudinal axis of the input device. 
     
     
         8 . A keyboard for an electronic device, comprising:
 an enclosure;   a cover coupled to the enclosure and defining an input surface;   a first actuator within the enclosure and coupled to the cover, the first actuator configured to impart, to the cover, a first force along a first axis that is substantially parallel to the input surface; and   a second actuator within the enclosure and coupled to the cover, the second actuator configured to impart, to the cover, a second force along a second axis that is perpendicular to the first axis and substantially parallel to the input surface;   wherein the keyboard is configured to alternate between actuating the first actuator and the second actuator in response to successive force inputs on the input surface.   
     
     
         9 . The keyboard of  claim 8 , wherein:
 the keyboard is incorporated into an electronic device;   the electronic device comprises a display coupled to the enclosure, wherein the display is distinct from the keyboard;   the input surface comprises input regions representing character input keys; and   the first actuator and the second actuator are configured to provide haptic feedback to a user to induce a sensation representative of a mechanical key.   
     
     
         10 . The keyboard of  claim 9 , further comprising a force sensing system within the enclosure configured to detect the successive force inputs on the input surface. 
     
     
         11 . The keyboard of  claim 9 , wherein the first and second actuators are linear actuators each comprising:
 a coil; and   a magnet configured to move in response to a current being passed through the coil.   
     
     
         12 . The keyboard of  claim 8 , wherein:
 the first actuator is configured to oscillate along the first axis to impart the first force to the cover; and   the second actuator is configured to oscillate along the second axis to impart the second force to the cover.   
     
     
         13 . A force sensing system for an electronic device, comprising:
 a cover defining an input surface comprising multiple input regions each corresponding to an input key, the cover configured to locally deform in response to an input force applied to an input region of the multiple input regions;   a capacitive sense layer below the cover;   a compliant material between the cover and the capacitive sense layer and below the input regions; and   a processor electrically coupled to the capacitive sense layer and configured to:
 determine a force value of the input force based on a change in capacitance between the capacitive sense layer and an input member applied to the input region; and 
 determine a location of the input force based on which of a set of electrodes detected the change in capacitance. 
   
     
     
         14 . The force sensing system of  claim 13 , wherein:
 the cover is formed from a glass;   the force sensing system is coupled to a lower portion of an enclosure of a notebook computer and is configured as a keyboard for the notebook computer;   the multiple input regions are visually differentiated to define a keyboard for the notebook computer; and   the notebook computer comprises a display coupled to an upper portion of the enclosure.   
     
     
         15 . The force sensing system of  claim 14 , wherein the force sensing system is configured to differentiate between force inputs having centroids about 3.0 cm apart or less. 
     
     
         16 . The force sensing system of  claim 14 , wherein:
 the glass has an elastic modulus in a range of about 60 to about 80 GPa;   the glass has a thickness in a range of about 0.1 to about 0.5 mm; and   the compliant material has a thickness in a range of about 0.5 mm to about 2.0 mm.   
     
     
         17 . The force sensing system of  claim 16 , wherein the compliant material is a foam. 
     
     
         18 . The force sensing system of  claim 13 , wherein the force sensing system does not include another capacitive sense layer between the cover and the compliant material. 
     
     
         19 . The force sensing system of  claim 13 , wherein the capacitive sense layer comprises a set of electrodes each having an area that is the same or smaller than an area of the input regions.