A multi-point touch screen suitable for a mobile apparatus is disclosed, which can output accurate touch images of a touch region by scanning, line by line, the touch region via an induction region positioned below the touch region. The internal opening includes a narrowed portion and a divergent portion which accommodates variable sizes of subject anatomy. The transition portion is oriented to channel the combustion gases towards the nozzle portion. A system for sensing the temperature of an integrated circuit includes a first current source providing a source current to a node. The interference components are then eliminated, and reverse phase shifting is applied to restore remaining components of the channel signals to their original phase condition.