Microsoft introduced a new multitouch platform, called LaserTouch, which includes hardware that’s cheap enough to retrofit any display into a touch screen.

LaserTouch is a system built on the cheap: the hardware only costs a couple hundred dollars, excluding the display–which can be a plasma television or overhead projector, for instance–and the computer that runs the software. Unlike Surface, which uses a camera within the table to detect touch and a rear-projection system to create the images, LaserTouch uses a camera that’s mounted on top of the display. Two infrared lasers, with beams spread wide, are affixed at the corners, essentially creating sheets of invisible light. When a person’s finger touches the screen, it breaks the plane of light–an action that’s detected by the camera above.