Image
scanners convert a visible image on a document or photograph, or an image in a transparent medium, into an electronic form suitable for
copying, storing or processing by a
computer. Reflective document image scanner is used for scanning reflective documents, such as documents and papers. Reflective image scanners typically have a controlled source of light, and light is reflected off the surface of a document, through an optics system, and onto an array of photosensitive devices. Penetrative document image scanner is used for scanning positive and negative films, such as slides and films. The reflective document image scanner is usually made in the form of
flat bed scanner, and the penetrative document image scanner is made in the form of
film scanner. An image scanner acquires image data by causing an image reading sensor to execute photoelectric conversion with respect to the reflected light obtained when a read object, such as a sheet-like document, a book, or a three-dimensional object, is irradiated with light. The image scanner has a transparent document holder on which an object to be read is held, an illumination device including an illuminating lamp and illuminating the read object placed on the document table, a lens assembly to focus the image of the illuminated scan line onto the surface of the optical
photosensor array, a
CCD sensor functioning as an image reading sensor, an optical set located between the document table and the CCD sensor.
