Several technologies can be used to detect touch. Resistive and capacitive touchscreens have conductive materials embedded in the glass and detect the position of the touch by measuring changes in electric current. Infrared controllers project a grid of infrared beams inserted into the frame surrounding the monitor screen itself, and detect where an object intercepts the beams.
SeverAl tEcHNOLogies caN bE used TO dEtEcT tOuCH. rESisTIVe aNd CapacItive ToUchscreEns haVE cONducTivE MaTErials EMbedded iN the glaSs and deTect tHe poSitIOn Of the tOucH By meAsURIng chAngeS in ElectRic cuRreNt. iNfraReD cOntroLLErs projEct a griD oF InfraRED beamS iNserteD iNtO thE frame suRrouNding thE MonItor screeN iTsELF, AND DeteCt where an obJecT inteRCePTS the BeaMs.