US Patent 8354640 Optically based planar scanner

Apparatus and methods for providing an optically based planar scanner for generating an image are provided. In one embodiment, the apparatus includes a switchable Bragg grating. An area of the switchable Bragg grating is configured to be activated to direct light to a platen. The platen is configured to reflect the light to a waveguide or to refract the light. The light reflected to the waveguide is guided to a light detector. By activating a number of the areas of the switchable Bragg grating and measuring the intensity of the light with a light detector, an image of an object contacting the platen may be formed.