A "double-touch" input method is described that is particularly suitable for use as a substitute for a "double-click" input from a mouse or trackball, and that is particularly suitable for use with a touch panel. Briefly, the input method involves contacting a touch panel at a first location (for example, over an area where an icon is displayed) with a first finger. Before a predetermined period of time T.sub.wait elapses, a second finger "taps" the panel at a second location. The location tapped by the second finger is greater than a predetermined distance from the first location tapped by the first finger. In addition, the tap by the second finger is shorter than a second predetermined period of time T.sub.tap. After the tap by the second finger, the first finger is still in contact with the touch panel. The position of the first finger after the tap should be within a predetermined range of its position just prior to the tap. Apparatus in the form of a device driver is described for detecting a double touch input.

An eraser for use on an electronic whiteboard with a protrusion area on the erasing surface forming a convex area on the erasing surface for establishing a positive point of contact with the whiteboard; an electronic whiteboard system including such an eraser, a controller for storing data relating to information written on and erased from the whiteboard data, and a filter for preventing the storage of digital data relating to contacts with the whiteboard not attributable to normal writing or erasing actions.

A front cover assembly is provided for use with a touch sensitive display device. The touch sensitive display device includes a display such as a Cathode Ray Tube (CRT) or Liquid Crystal Display (LCD). The front cover assembly has a top cover, an infrared bezel and a piece of glass. The top cover is inserted into a mold along with the piece of glass. The top cover and glass are then held in place by a vacuum while polyurethane is injected to fill the void between the glass and the top cover and the mold. The polyurethane is injected using injection molding techniques. The polyurethane used must have the properties of flexibility, durability and must also be transparent to infrared light. The polyurethane provides a mechanical lock around the glass and top cover and thus the polyurethane compensates for the different rates of expansion and contraction of the glass and the top cover due to temperature variations in the ambient environment. The polyurethane provides a mechanical lock that prevents liquids from seeping or entering from the top portion of the front cover assembly protecting the touch sensitive display device.

In the coordinate detection of resistive film system, detection of the coordinates of simultaneously designated two points is made possible. On a touch panel composed of two conductive films, whether input is made in a point or simultaneously at two points is judged by a current monitor. Simultaneous inputs at two points decrease the apparent resistance of the conductive film, and can be detected by an increase in the current. If the input of a point is identified, the coordinate data of the input point are retained as latest coordinate data in a RAM. If simultaneous inputs at two points are identified, coordinate data are obtained from the coordinate data retained in the RAM and from the potentials in the x and y directions, obtained from two conductive films constituting a touch panel, through amplifiers, and are outputted, together with the coordinate data retained in the RAM, as the coordinate data of the two points.

A touch screen mounting assembly for a liquid crystal display panel (LCD) and a method for fabricating a touch screen mounting assembly for use on a LCD panel are disclosed. The mounting assembly includes a bottom frame that has a plurality of attachment means mounted thereon, a backlight panel that has a plurality of pressure-sensitive transducers mounted thereon, a liquid crystal display panel, and a top frame for exerting pressure when mounted to the bottom frame such that a plurality of compressible springs biases the LCD panel towards the bottom frame when touched or contacted by a user. The pressure-sensitive transducers may be suitably piezoelectric transducers that produce a flow of electricity upon sensing a pressure.