The basic working principle of a photocopier can be summarized in the following key steps:
1. Optical imaging
Component composition: The optical part of the copier is mainly composed of a light source, a lens and a mirror.
How it works: When the document we are going to copy is placed on the glass plate of the copier, the light source emits light and is focused on the surface of the document through the lens and reflectors. When light passes over the surface of the file, it is reflected or absorbed to form an optical image. This process converts the image information on the surface of the file into an optical signal.
Second, charge induction
Photodrum action: The photodrum in the photocopier (also known as the photodrum) plays a key role in this step. The light-sensitive drum is coated with a special material that when light hits the light-sensitive drum, the illuminated area loses its charge, while the unilluminated area retains it. In this way, a charge distribution corresponding to the optical image is formed on the sensitive drum.
Third, electrostatic replication
Electrostatic transfer: Next, the photocopier transfers the charge distribution on the photosensitive drum to another medium, usually a web with electrostatic properties. A charging rod on a photocopier gives a static charge to the web so that the entire surface carries the same charge. The charge distribution on the sensitive drum is then transferred to the web, creating a charge distribution identical to the original file.
Fourth, fixing
Component composition: The fixing part is mainly composed of hot roller, fixing agent and press roller.
Working process: When the web is passed through the hot roller, the hot roller will heat the fixer, making it melt. The web is then passed through a fixer, which attaches to the charged area on the web, creating a visible replica image. Finally, the web passes through the press roller to fix the fixer on the paper to complete the replication process.
