Abstract: A touch panel module includes a surface panel, a band splitter, an optical unit and a control unit. Retro-reflectors are respectively positioned on three peripheral sides of the surface panel, and the band splitter is positioned on the retro-reflector positioned at one peripheral side of the surface panel, where the band splitter totally reflects a light beam within a first band while a light beam with a second band transmits through the band splitter. The optical unit is utilized for generating a first band beam within the first band and for receiving a reflected first band beam from one of the retro-reflectors to generate a first signal, and the control unit performs touch point detection according to the first signal.