Patent ID: 7391540

Claim:
A sheet-fed scanner, comprising: a housing; a sheet-feeding mechanism for transporting a document across a scan region; a first scanning module, which is fixed in the housing, for scanning a front side of the document in the scan region, wherein the first scanning module comprises a first image sensor, a first lens and at least one first reflecting mirror; a first actuator for actuating the at least one first reflecting mirror; and a first background component, which is fixed in the housing and located in the scan region and has a plurality of sections having different reflectivities, wherein: the first actuator actuates the at least one first reflecting mirror such that the first image sensor selectively senses one of the sections of the first background component through the first lens and the at least one first reflecting mirror, as a first scan background when the first image sensor senses the front side of the document; and the at least one first reflecting mirror is placed on a base having two projections in contact with a lower surface of the at least one first reflecting mirror and an elastic member presses against an upper surface of the at least one first reflecting mirror toward the base, such that when the first actuator pushes a side of the at least one first reflecting mirror upwards, the at least one first reflecting mirror parts from one of the projections and the at least one first reflecting mirror is rotated.