Patent ID: 8462395

Claim:
In an image acquisition apparatus, including a housing having an internal space and a substantially transparent surface for supporting a tangible document during an image acquisition operation, a document sensing device for detecting if at least a portion of said transparent surface is covered by said tangible document, said document sensing device comprising: (a) a transparent support structure for supporting at least one edge of said tangible document comprising: i. a first supporting element having a first supporting surface for supporting a first edge of said tangible document, wherein said supporting surface is disposed in alignment with a first edge of said transparent surface; and ii. a first transparent attachment structure for firmly attaching said support structure to said housing; (b) a layer of coating configured to reflect light, wherein said layer of coating covering at least a portion of the external surfaces of said transparent support structure; (c) a first light source; and (d) a light intensity sensor disposed inside said internal space, wherein said first light source is disposed inside said image acquisition apparatus, directionally illuminating said first attachment structure towards said first supporting element; wherein said layer of coating reflects a substantial portion of the light transmitted by said first light source, towards said transparent surface and said internal space; wherein a substantial portion of said light is sensed by said light intensity sensor, said transparent surface being exposed, whereby said light intensity sensor detected a high intensity level, and wherein when said tangible document blocks a substantial portion of said light from reaching said transparent surface, said light intensity sensor detected a low intensity level; and wherein the difference between said high intensity level and said low intensity level is associated with the presence of said tangible document on said transparent surface.