Patent ID: 9690430
Date: 2017-06-27
CPC Classifications: G06F

Claim:
1. A touch detection apparatus, comprising: a plurality of lighting units configured to emit light including invisible wavelength components onto a screen; a control unit configured to control the emission of light from the plurality of lighting units according to a plurality of lighting patterns including: a first lighting pattern to cause one or more of the plurality of lighting units associated with a first group to emit light such that a shadow of an object is formed at a first position on the screen; and a second lighting pattern to cause one or more of the plurality of lighting units associated with a second group to emit light such that the shadow of the object is formed at a second position on the screen, the second position being different from the first position, wherein at least one of the plurality of lighting units associated with the second group is different from the plurality of lighting units associated with the first group; an image sensing unit configured to obtain, according to control by the control unit, a plurality of captured images of the screen including: a first captured image of the screen, where the shadow of the object is formed at the first position, being lighted by the one or more of the plurality of lighting units associated with the first group; and a second captured image of the screen, where the shadow of the object is formed at the second position, being lighted by the one or more of the plurality of lighting units associated with the second group, wherein the image sensing unit is configured to have a sensitivity to the invisible wavelength components of the light emitted from the plurality of lighting units; and a detection unit configured to detect a touch to the screen by the object based on the plurality of captured images including the first captured image of the screen, where the shadow of the object is formed at the first position, being lighted by the one or more of the plurality of lighting units associated with the first group and the second captured image of the screen, where the shadow of the object is formed at the second position, being lighted by the one or more of the plurality of lighting units associated with the second group.