Application principle of the hottest laser printer

Application principle of laser printer

in the printing world of a large number of black-and-white documents, there is no doubt that laser printer is absolutely the best. Because of this, it has become the most common output tool in the office and SOHO family and other commercial fields. Due to the advantages of fast speed, high resolution, no paper picking, waterproof and easy preservation, coupled with the increasingly low price, its popular layout is even extended to general personal printing purposes. As for color laser printers, although they have the advantages of speed and quality, they are too expensive in price, so the market share of color output is far less than that of popular color inkjet printers. In the laser printer countries, whether color or black-and-white, HP has been the leader for a long time. This is the first time that the scientific community has used light to drive a macro object and realize macro driving. The second is Canon, which is also the largest supplier of laser engines. As for other famous world-class laser printer manufacturers, there are okidata, Lexmark, Epson, NEC, Xerox, Fujitsu and IBM. The basic principle of laser printing the most important element in a laser printer is the photosensitive drum, which is commonly known as the selenium drum, because the whole printing action and principle take the photosensitive drum as the center and act repeatedly. The whole action in laser printing can be said to be a cycle of seven steps, including charging, exposure, development (the market demand for plastic products in China will continue to grow), transferring, fusing, cleaning and erasing. In detail, after the user gives the printing instruction in the application program, the prologue of the whole laser printing process starts with the "charging" action, that is, first charge the drum with negative or positive charge, and then "expose" the image data processed by the printer processor to the drum through the beam, forming the so-called electrostatic latent image "potential is zero". Then let the toner in the toner cartridge be charged. At this time, the electrostatic latent image surface on the rapidly rotating photosensitive drum will absorb the charged toner and "image" the graphic image when it passes through the toner cartridge. Then pull the paper pulled in by the printer's paper feed box, and through the "image conversion" step, make the paper surface with opposite positive or negative charges. Due to the attraction of the opposite sex, the toner on the photosensitive drum can be adsorbed on the paper. In order to make the toner more tightly attached to the paper, then the toner is "fixed" on the paper in the way of high temperature and high pressure, which is why every newly printed paper is hot. Then use a scraper to remove the residual carbon on the drum? quot; Clear ". The final action is" image removal ", that is, to remove the electrostatic latent image, so that the potential on the surface of the photosensitive drum returns to the initial state, so as to carry out the next cycle action. The basic element of laser printing, the most important element of laser printer, as large as the photosensitive drum, charging element and imaging unit. Basically, the photosensitive drum is coated with optical photoconductor The photoconductor of an aluminum tube has the characteristics that it is a conductor when illuminated by light and an insulator when in a dark room. With this characteristic, exposure and imaging can be completed. At present, most of the laser printers on the market combine the photosensitive drum with the toner cartridge. For example, HP and Lexmark brands. In addition, there are also photosensitive drums and toner cartridges separated into one, such as Epson. Since the photosensitive drum (like the toner cartridge) is also a consumable with service life limit, if the user uses a printer with a photosensitive drum separated from the toner cartridge, and determines that the toner cartridge still has sufficient toner, but the printing image quality is ambiguous, then the photosensitive drum must be "dead", as long as the coincidence is to replace it with a new photosensitive drum, the printing quality can be restored. As for the toner cartridge of the integrated photosensitive drum, it is widely used in aerospace, petrochemical, machinery manufacturing, wire, cable, textile, fiber, plastic, rubber, ceramics, metal materials and manufacturing industries. No matter how long the photosensitive drum lives, as long as the toner is exhausted, the whole toner cartridge needs to be replaced. The charging element in the laser printer is the most important mechanism for the photosensitive drum to be charged with positive or negative charges. The most common are corona charger and charging roller. However, since corona charger will produce a large amount of ozone, it is gradually replaced by charging roller. The main tasks of the imaging unit include charging toner, handling toner, controlling the thickness of toner in different areas, and positioning of toner

from: printer maintenance