The scanner consists of three parts: optical part, mechanical transmission part and conversion circuit. The core part of the scanner is the photoelectric conversion unit that completes photoelectric conversion. At present, the photoelectric conversion part of most scanners is photosensitive devices (including CCD, CIS and CMOS).
When the scanner works, the light is first illuminated by the light source on the desired draft, producing reflected light (reflected manuscript) or transmitted light (transmission manuscript) that represents the feature of the image. The optical system collects the light, focuses it on the photosensitive device, transforms the light signal into the electrical signal by the photosensitive device, and then the A/D (Analog/Digital) conversion and processing of the signals by the circuit part, and produces the corresponding digital signal to the computer. When the mechanical transmission mechanism is controlled by the control circuit, the scanning head which is equipped with the optical system and the CCD is moved in relative motion with the draft. All the drawings are scanned, and a complete image is entered into the computer.
Editor’s Note: This post was Published by Proffisy on 03 May,2018.