US Patent 7478750 Reading device of scanning apparatus

By combining a sensing module having a lens and an image sensor with a carriage module having a mirror set, a reading device of a scanning apparatus is assembled. The sensing module further includes two channels at bilateral sides of the lens and two guiding slots disposed on external sides of the channels. The carriage module further includes two linear tracks corresponding to the channels and two bolt hole pedestals corresponding to the guiding slots. The sensing module is glided on the carriage module when the linear tracks are embedded in corresponding channels, thereby correcting the desired magnification.