What Principle is the Scanner Based on

25.03.2021 0 iCODIS Official

1. Introduction of Scanner

Scanner is a kind of office equipment that is frequently used in daily office. The main purpose is to scan paper documents into electronic documents and then transfer them to a computer for storage and use. So what is the design principle of the scanner?

2. The design principle of the scanner

The scanner is mainly composed of a manuscript table, an optical imaging part, a photoelectric conversion part, and a mechanical transmission part.

(1) The manuscript table is mainly used to place the scanned manuscript.

(2) The optical imaging part is commonly known as the scanning head, and its accuracy directly affects the fidelity of the scanned image.

(3) The photoelectric conversion part refers to the main board inside the scanner, which is the control system of the scanner.

(4) The mechanical transmission part mainly includes a stepping motor, a driving belt, a sliding guide and a gear, etc., which are used to move the optical imaging part to scan the manuscript.

When the scanner scans the image frame, the linear CCD divides the scanned image into lines, and the width of each line is about 10 μm. The light source irradiates the light on the image manuscript to be scanned, generating reflected light (generated by the reflective manuscript) or transmitted light (generated by the transmitted manuscript), and then reflected into the linear CcD by the reflector group. The CcD image sensor converts into currents of different magnitudes according to the intensity of the reflected light. After A/D conversion processing, the electrical signal is converted into a digital signal, that is, one line of image data is generated. At the same time, under the control of the control circuit, the mechanical transmission mechanism rotates the stepping motor to drive the driving belt, thereby driving the optical system and the CcD scanning device to move in parallel with the original document to be scanned on the transmission guide rail, so that the original image document to be scanned is scanned line by line, after which, all the original images finally scanned completely.