Patent ID: 7085023

Claim:
An image-reading apparatus comprising at least one light source configured to illuminate a surface of a document with light; a light-guiding mechanism including a light incoming face and a light outgoing face, the light-guiding mechanism configured to allow light emitted from said light source to travel in the light-guiding mechanism and guide the light to a linear objective reading region; an optical system configured to collect light reflected on the surface of said document; and a reading sensor configured to read an image of the document, wherein said light-guiding mechanism includes, at its top face, said light outgoing face in a shape of a substantially rectangular parallelopiped which extends in a longer axial direction of said linear objective reading region, and includes, at its base, a light source-accommodating section in which said light source is disposed, a wall of said light source-accommodating section serving as said light incoming face; a first wall and a second wall of said light-guiding mechanism serve as a first face and a second face and are formed to extend parallel to the longer axial direction of said light-guiding mechanism, and a third side wall and a fourth side wall of said light-guiding mechanism serve as a seventh face and an eighth face and are formed to extend perpendicular to the longer axial direction of said light-guiding mechanism; in the shorter axial direction of said linear objective reading region of said document, light fluxes, which are emitted from said light source and pass through said light source-accommodating section and enter the light incoming face of said light-guiding mechanism, are reflected on said first face and said second face so as to be guided to said light outgoing face and to said linear objective reading region, and said light guiding mechanism further includes a reflecting face configured to reflect a part of the light fluxes from said light outgoing face of said light-guiding mechanism onto the surface of the document, so as to guide said part of the light fluxes to said linear objective reading region.