초록 ▼

A touch panel system having enhanced touch detection which distinguishes between deliberate actuations of the touch system and accidental and other false actuations. The system has a display surface surrounded by a multiplicity of light emitting elements and light receiving elements that define a gr

A touch panel system having enhanced touch detection which distinguishes between deliberate actuations of the touch system and accidental and other false actuations. The system has a display surface surrounded by a multiplicity of light emitting elements and light receiving elements that define a grid of intersecting light paths. The display surface is scanned by sequentially enabling selected pairs of the light emitting and light receiving elements. False actuation rejection involves the use of one or more of three techniques: ignoring touches which fail to block a minimum number of contiguous beams in both axes, ignoring touches which block in excess of a specified maximum number of contiguous beams in either axis, and ignoring touches which are of a duration of less than a minimum specified time. The minimum and maximum size constraints on the size of the object touching the screen, and the minimum contact time are programmable. These criteria enable the system to distinguish many types of false hits or accidental touchings of the screen from deliberate touchings by a person selecting an item on the touch panel. An additional feature of the present invention is beam fault tolerance. Whenever a beam component fails, the system can determine exactly which beam element has failed, and can mask out that beam from all future determinations of whether a user selection is being made by touching the screen.

대표청구항 ▼

A touch panel comprising: a display surface having a defined perimeter; a multiplicity of light emitting elements and a multiplicity of light receiving elements; said elements located so that a multiplicity of light paths, defined by selected pairs of said light emitting and light receiving elements

A touch panel comprising: a display surface having a defined perimeter; a multiplicity of light emitting elements and a multiplicity of light receiving elements; said elements located so that a multiplicity of light paths, defined by selected pairs of said light emitting and light receiving elements, cross said display surface and also intersect each other within the perimeter of said display surface; beam blockage detection means, coupled to said light receiving elements, for generating a path blockage signal when the amount of light received by a selected light receiving element corresponds to a blocked light path; and computer means, coupled to said light emitting and light receiving elements and said beam blockage detection means, for controlling the operation of said touch panel, including scanning means for sequentially enabling selected pairs of said light emitting and light receiving elements; and touch detection means, responsive to path blockage signals from said beam blockage detection means, for comparing said path blockage signals with predefined criteria which distinguish between a deliberate touching of said display surface and false or accidental touching of said display surface, and for generating an output signal indicative of the location of said object when said path blockage signals meet said predefined criteria.