Patent ID: 8537138

Claim:
An optical touch apparatus, adapted to a display area, the optical touch apparatus comprising: at least one light source, disposed next to the display area and capable of providing a beam; at least one light guide unit, disposed next to the display area and in a transmission path of the beam, the light guide unit comprising: a light guide body, having a first surface, a second surface opposite to the first surface, at least one light incident surface connecting the first surface and the second surface, a third surface connecting the light incident surface, the first surface, and the second surface, and a fourth surface opposite to the third surface and connecting the light incident surface, the first surface, and the second surface, wherein the beam is capable of entering the light guide body through the light incident surface and is capable of being transmitted from the first surface to a sensing space in front of the display area; and a scattering structure, disposed on at least one of the second surface, the third surface, and the fourth surface, so that the beam is scattered to the first surface, wherein the scattering structure has a plurality of scattering patterns separated from each other, each of the scattering patterns comprising a resin composition and a plurality of scattering particles, wherein the scattering particles are dispersed in the resin composition, and a ratio of a weight percentage of the scattering particles to a weight percentage of the resin composition is substantially equal to or greater than 0.1; and at least one optical detector, disposed next to the display area and capable of detecting a change in light intensity of the beam in the sensing space.