Patent ID: 8654102
Filing Date: 2014-02-18
Classification: G06F

Abstract:
1. An optical touch system, capable of sensing a position of a touch object, the optical touch system comprising: a non-visible light source capable of emitting a non-visible beam, wherein the non-visible beam is an infrared beam; a screen disposed in a light path of the non-visible beam, wherein a part of the non-visible beam is capable of passing through the screen, the touch object reflects the part of the non-visible beam passing through the screen into an object beam when the touch object approaches or touches the screen, and the object beam passes through the screen; a first polarizing element disposed in the light path of the non-visible beam and located between the non-visible light source and the screen; an optical detector disposed in a light path of the object beam passing through the screen and capable of sensing the object beam; and a second polarizing element disposed in the light path of the object beam passing through the screen and located between the screen and the optical detector, wherein the first polarizing element is capable of being passed through by a first part beam of the non-visible beam having a first polarization direction and capable of blocking a second part beam of the non-visible beam having a second polarization direction, and wherein the screen further comprises a wave plate, the part of the non-visible beam is capable of passing through the wave plate, and another part of the non-visible beam is capable of being reflected to the second polarizing element, a polarization direction of the object beam is converted to the second polarization direction when the object beam reflected by the touch object passes through the wave plate, the second polarizing element is capable of being passed through by the object beam having the second polarization direction and capable of blocking the non-visible beam reflected by the wave plate and having the first polarization direction.