Patent ID: 7864161

Claim:
A system for detecting two-finger input on a touch screen, comprising: a display screen; a sensing grid arranged for sensing touch on said display screen; a plurality of electrodes arranged at corners of the sensing grid and being electrically connected to the sensing grid; a controller that receives an output from the sensing grid; and a control module that identifies (i) at least two points on the grid indicating locations of the display screen that have been touched by at least two fingers of a user and (ii) a geographic portion of the display screen based on said at least two points, wherein the geographic portion comprises a rectangle that is defined (ii)(a) wherein the at least two points having different X and Y coordinates and wherein sides of the rectangle comprise (ii)(a)(1) two active lines of the sensing grid in a horizontal direction corresponding to the Y coordinates of the at least two points and (ii)(a)(2) two active lines of the sensing grid in the vertical direction corresponding to the X coordinates of the at least two points, and (ii)(b) wherein at least one sensed line is connected between said at least two points and if only one vertical or one horizontal sense line is active on the sensing grid between said at least two points in response to the identified at least two points on the sensing grid touched by the at least two fingers of the user, then a size of the rectangle is calculated by (ii)(b)(1) the control module sensing a length of said at least one sensed line, and (ii)(b)(2) at a midpoint of said at least one sensed line, the control module calculating a second line that is perpendicular to said at least one sensed line, the second line having a same length as the length of said at least one sensed line, and (ii)(b)(3) based on the length defined by a location of said at least two points on the sensing grid touched by the at least two fingers of the user, and a width defined by two end points of the second line, the control module providing length and width coordinates of the rectangle to be identified on the display screen.