Touch screen using infrared camera hardly affected by external disturbance light

A touch screen comprising:

• a body having a screen part to which an image is output;
• an infrared radiation base disposed around the screen part in transverse (X axis) and longitudinal (Y axis) directions and divided into a plurality of sub-bases including at least one infrared emitting element emitting infrared light in order to prevent malfunction caused by external disturbance light;
• and
• infrared cameras receiving the infrared light emitted from the infrared emitting element of each sub-base of the infrared radiation base, and detecting a position of an object touched on the screen part according to whether or not the infrared light emitted from the infrared emitting element is received,
• wherein two infrared cameras are provided, each of which has an intersecting orientation angle at one edge of the screen part at which the infrared radiation base is not disposed, and
• wherein each infrared camera includes:
• an infrared detector having a plurality of infrared receiving cells;
• a lens having an angle of view for receiving the infrared light incident onto the entire screen part;
• a band-pass filter filtering the infrared light with a wavelength band passing through the lens to pass only the filtered infrared light;
• an infrared receiver receiving the infrared light filtered by the band-pass filter;
• and
• an interface, when the infrared detector detects a touch of an object, outputting the detected results to the body.