Abstract: A touch sensitive surface has emitters and detectors arranged around a periphery of the touch sensitive surface. The emitters produce optical beams that are received by the detectors. A stylus is configured to disturb one or more of the optical beams by a variable amount when in contact with the touch sensitive surface. The variable amount depends on an amount of force applied to the stylus towards the touch sensitive surface. A controller of the touch sensitive surface is configured to determine the touch strength of a touch event performed by the stylus based on disturbances of one or more of the optical beams. The touch strength provides a measure of the amount of force applied to the stylus.

Abstract: A touch sensitive surface has emitters and detectors arranged around a periphery of the touch sensitive surface. The emitters produce optical beams that are received by the detectors. A stylus is configured to disturb one or more of the optical beams by a variable amount when in contact with the touch sensitive surface. The variable amount depends on an amount of force applied to the stylus towards the touch sensitive surface. A controller of the touch sensitive surface is configured to determine the touch strength of a touch event performed by the stylus based on disturbances of one or more of the optical beams. The touch strength provides a measure of the amount of force applied to the stylus.

Abstract: An optical touch-sensitive device has the capability to determine touch locations of multiple simultaneous touch events. The touch events disturb optical beams propagating across the touch sensitive surface. With multi-touch events, a single beam can be disturbed by more than one touch event. In one aspect, a non-linear transform is applied to measurements of the optical beams in order to linearize the effects of multiple touch events on a single optical beam. In another aspect, the effect of known touch events (i.e., reference touches) is modeled in advance, and then unknown touch events are determined with respect to the reference touches.

Abstract: An optical touch-sensitive device has the capability to determine touch locations of multiple simultaneous touch events. The touch events disturb optical beams propagating across the touch sensitive surface. With multi-touch events, a single beam can be disturbed by more than one touch event. In one aspect, a non-linear transform is applied to measurements of the optical beams in order to linearize the effects of multiple touch events on a single optical beam. In another aspect, the effect of known touch events (i.e., reference touches) is modeled in advance, and then unknown touch events are determined with respect to the reference touches.

Abstract: An optical touch-sensitive device has the capability to determine touch locations of multiple simultaneous touch events. The touch events disturb optical beams propagating across the touch sensitive surface. With multi-touch events, a single beam can be disturbed by more than one touch event. In one aspect, a non-linear transform is applied to measurements of the optical beams in order to linearize the effects of multiple touch events on a single optical beam. In another aspect, the effect of known touch events (i.e., reference touches) is modeled in advance, and then unknown touch events are determined with respect to the reference touches.

Abstract: An optical touch-sensitive device has the capability to determine touch locations of multiple simultaneous touch events. The touch events disturb optical beams propagating across the touch sensitive surface. With multi-touch events, a single beam can be disturbed by more than one touch event. In one aspect, a non-linear transform is applied to measurements of the optical beams in order to linearize the effects of multiple touch events on a single optical beam. In another aspect, the effect of known touch events (i.e., reference touches) is modeled in advance, and then unknown touch events are determined with respect to the reference touches.

Abstract: An optical touch-sensitive device has the capability to determine touch locations of multiple simultaneous touch events. The touch events disturb optical beams propagating across the touch sensitive surface. With multi-touch events, a single beam can be disturbed by more than one touch event. In one aspect, a non-linear transform is applied to measurements of the optical beams in order to linearize the effects of multiple touch events on a single optical beam. In another aspect, the effect of known touch events (i.e., reference touches) is modeled in advance, and then unknown touch events are determined with respect to the reference touches.