Force imaging input device and system

Abstract

A force imaging touch pad includes first and second sets of conductive traces separated by a spring membrane. When a force is applied, the spring membrane deforms moving the two sets of traces closer together. The resulting change in mutual capacitance is used to generate an image indicative of the amount or intensity of the applied force. A combined location and force imaging touch pad includes two sets of drive traces, one set of sense traces and a spring membrane. In operation, one of the drive traces is used in combination with the set of sense traces to generate an image of where one or more objects touch the touch pad. The second set of drive traces is used in combination with the sense traces and spring membrane to generate an image of the applied force's strength or intensity.

1 . A touch location and force sensing apparatus, comprising:
 a first member including a plurality of first conductive elements configured for detecting a location of a touch input, and a plurality of second conductive elements; and   a second member including a plurality of third conductive elements configured for detecting the force of the touch input, the second member spatially separated from the first member through a mechanism by which the first and second members are brought into closer proximity when the touch input is received;   wherein the first, second and third conductive elements are configured for generating information associated with the location and force of the touch input.   
     
     
         2 . The apparatus of  claim 1 , the plurality of first conductive elements configured for mutual capacitance touch sensing. 
     
     
         3 . The apparatus of  claim 1 , the plurality of first conductive elements formed as capacitive touch sensing plates. 
     
     
         4 . The apparatus of  claim 1 , the plurality of second conductive elements configurable as sense lines for mutual capacitance touch sensing. 
     
     
         5 . The apparatus of  claim 1 , the plurality of second conductive elements configurable for mutual capacitance force sensing. 
     
     
         6 . The apparatus of  claim 1 , the plurality of third conductive elements configured for mutual capacitance force sensing. 
     
     
         7 . The apparatus of  claim 1 , the plurality of second and third conductive elements arranged as vertically aligned plates for mutual capacitance force sensing. 
     
     
         8 . The apparatus of  claim 1 , the plurality of second conductive elements including a first plurality of conductive traces. 
     
     
         9 . The apparatus of  claim 8 , the plurality of third conductive elements including a second plurality of conductive traces orthogonal to the first plurality of conductive traces. 
     
     
         10 . The apparatus of  claim 1 , further comprising a deformable member disposed between the first member and the second member, wherein the deformable member provides the mechanism by which the first and second members are brought into closer proximity when the touch input is received. 
     
     
         11 . A touch location and force detector, comprising:
 a plurality of first conductive elements configured for detecting a location of a touch input; and   one or more second conductive elements and one or more third conductive elements configurable for detecting the force of the touch input, the one or more second conductive elements spatially separated from the one or more third conductive elements through a mechanism by which the one or more second conductive elements and the one or more third conductive elements are brought into closer proximity when the touch input is received;   wherein the plurality of first conductive elements, the one or more second conductive elements, and the one or more third conductive elements are configured for generating information associated with the location and force of the touch input.   
     
     
         12 . The touch location and force detector of  claim 11 , the plurality of first conductive elements configured for mutual capacitance touch sensing. 
     
     
         13 . The touch location and force detector of  claim 11 , the plurality of first conductive elements formed as capacitive touch sensing plates. 
     
     
         14 . The touch location and force detector of  claim 11 , the one or more second conductive elements further configurable as sense lines for mutual capacitance touch sensing. 
     
     
         15 . The touch location and force detector of  claim 11 , the one or more second conductive elements configurable for mutual capacitance force sensing. 
     
     
         16 . The touch location and force detector of  claim 11 , the one or more third conductive elements configured for mutual capacitance force sensing. 
     
     
         17 . The touch location and force detector of  claim 11 , the one or more second and third conductive elements arranged as vertically aligned plates for mutual capacitance force sensing. 
     
     
         18 . The touch location and force detector of  claim 11 , the one or more second conductive elements including a first plurality of conductive traces. 
     
     
         19 . The touch location and force detector of  claim 18 , the one or more third conductive elements including a second plurality of conductive traces orthogonal to the first plurality of conductive traces. 
     
     
         20 . The touch location and force detector of  claim 11 , further comprising a deformable member disposed between the one or more second conductive elements and the one or more third conductive elements, wherein the deformable member provides the mechanism by which the one or more second conductive elements and the one or more third conductive elements are brought into closer proximity when the touch input is received.