Abstract: A combination includes a family of cartridge drives (12) including a first cartridge drive and a second cartridge drive, and a family of cartridges (14) including a first cartridge and a second cartridge. The first cartridge drive includes a first protrusion pattern (32), and the second cartridge drive includes a second protrusion pattern (32) that is different than the first protrusion pattern (32). The first cartridge includes a first recess pattern (62) that receives the first protrusion pattern (32) thereby allowing full insertion of the first cartridge into the first cartridge drive. The second cartridge includes a second recess pattern (62) that receives the second protrusion pattern (32) thereby allowing full insertion of the second cartridge into the second cartridge drive. The second protrusion pattern (32) can impede full insertion of the first cartridge into the second cartridge drive.

Abstract: A method, computer readable medium, and touch sensor system for reducing the effects of contaminants on an acoustic touch sensor. Acoustic energy is transmitted across the touch sensor substrate. Any perturbations in the acoustic energy induced by environmental events, such as valid touches or contaminants, are sensed and analyzed. If the perturbation exhibits a monotonic growth over a time period, it is considered to be a valid touch. If the perturbation exhibits a non-monotonic growth over the time period, it is considered a contaminant.

Abstract: A method, computer readable medium, and touch sensor system for reducing the effects of contaminants on an acoustic touch sensor. Acoustic energy is transmitted across the touch sensor substrate. Any perturbations in the acoustic energy induced by environmental events, such as valid touches or contaminants, are sensed and analyzed. If the perturbation exhibits a monotonic growth over a time period, it is considered to be a valid touch. If the perturbation exhibits a non-monotonic growth over the time period, it is considered a contaminant.

Abstract: A combination includes a family of cartridge drives (12) including a first cartridge drive and a second cartridge drive, and a family of cartridges (14) including a first cartridge and a second cartridge. The first cartridge drive includes a first protrusion pattern (32), and the second cartridge drive includes a second protrusion pattern (32) that is different than the first protrusion pattern (32). The first cartridge includes a first recess pattern (62) that receives the first protrusion pattern (32) thereby allowing full insertion of the first cartridge into the first cartridge drive. The second cartridge includes a second recess pattern (62) that receives the second protrusion pattern (32) thereby allowing full insertion of the second cartridge into the second cartridge drive. The second protrusion pattern (32) can impede full insertion of the first cartridge into the second cartridge drive.

Abstract: A sealing system for use with acoustic touchscreens is provided. The system includes a seal coupled to a frame, the frame being positioned directly over the acoustic touchscreen components, e.g., acoustic transducers, reflective arrays, etc. such that the seal prevents contamination of the underlying components. The system uses a plurality of tensioning elements that are either integral to, or separate from, the frame. The tensioning elements are preferably coupled at the four corners of the CRT, and more preferably coupled to the CRT mounting tabs. Assuming an approximately spherically curved touchscreen surface, the tensioning elements provide a uniform compressive force per unit length along the entire perimeter of the seal. As a consequence of the tensioning elements, the frame can be extremely thin, lightweight, and flexible, thus allowing it to substantially conform to the shape of the touch surface. Additionally, a very small and uniform gap can be maintained between the frame and the touch surface, e.

Abstract: A method for minimizing the shadowing effects of a contaminant on a surface acoustic wave touchscreen is provided. The disclosed system compares the measured waveform against a baseline waveform for each axis and validates the new touch if the measured waveform is different from the baseline waveform for either axis. As a consequence of this approach, even if the new touch lies within the shadow created by a contaminant in one axis, the new touch is still validated as it is not within the shadow created by the contaminant in the second axis. In one embodiment, after the system determines that the measured response is different from the baseline in at least one axis, the system compares the new touch to one or more selection criteria to insure that it is a valid touch and not due to a contaminant, electrical noise, or other improper source.