Patent ID: 8144271

Claim:
A multi-touch sensing system, comprising: an optical waveguide having an index of refraction sufficient to cause light of at least one wavelength received in a predetermined direction to undergo total internal reflection within the optical waveguide, the optical waveguide having first and second sides; a compliant layer having a first surface disposed adjacent to and spaced from the first side of the optical waveguide, the compliant layer being sufficiently deformable upon depression of the compliant layer to allow portions of the first surface of the compliant layer to contact the optical waveguide, and the first surface of the compliant layer has an index of refraction sufficiently similar to the index of refraction of the optical waveguide to cause, upon the first surface of the compliant layer contacting the optical waveguide, some of the light undergoing total internal reflection to scatter and to escape the optical waveguide; and an image sensor adapted to detect at least some of the light that escapes from the optical waveguide.