Optical Touch Panel Having SMT Components As Optical Gates

An optical touch panel comprising:

• a rectangular position-detecting surface;
• a frame-shaped circuit board surrounding the rectangular position-detecting surface;
• a plurality of light-emitting elements configured for emitting a plurality of light beams, wherein the plurality of light-emitting elements are arranged at various points along a first side of the rectangular position-detecting surface and disposed on the frame-shaped circuit board;
• a plurality of light-receiving elements configured for receiving the plurality of light beams emitted by the plurality of light-emitting elements;
• a plurality of surface mount technology (SMT) components configured as optical gates for isolating ambient light to prevent erroneous light detection, wherein the plurality of SMT components and the plurality of light-receiving elements are disposed simultaneously on the frame-shaped circuit board via a single SMT assembly process;
• and
• a control circuit configured for causing the plurality of light-emitting elements to emit the plurality of light beams in a predetermined order and further configured for causing the plurality of light-receiving elements to receive the plurality of light beams, thereby forming optical paths on the position-detecting surface in a grid pattern;
• wherein the plurality of SMT components and the plurality of light-receiving elements are alternatively arranged at various points along a second side of the rectangular position-detecting surface opposite to the first side and disposed on the frame-shaped circuit board, and wherein the plurality of light-receiving elements are arranged at locations behind the plurality of SMT components.