How Laser Printers Work? We all use printers in our daily office work. Today we will look at the working principle of laser printer.

The working principle of laser printer:

Convert the printing signal from the computer into a pulse signal and transmit it to the laser. At this time, the charging stick has completed the uniform charging of the OPC drum surface, and the laser emits laser to offset the charge of the image part on the OPC drum, so that an invisible electrostatic image is formed on the OPC drum, and the toner on the magnetic roller is adsorbed to the OPC drum through the principle of electrostatics. At this time, we can observe the image on the OPC drum with the naked eye.

Then the transfer is carried out through the transfer roller. Since the voltage on the transfer roller is higher than the voltage on the OPC drum, the toner on the OPC drum is pulled onto the paper. At this time, the paper has formed the image we want to print, but the toner floats on the paper and can be wiped off gently by hand, so it must be fixed, that is, heated and pressurized to make the toner melt and penetrate into the fiber of the paper to complete the entire printing process.

image of How Laser Printers Work

Key components: photosensitive drum, magnetic roller, magnetic roller blade, cleaning blade, charging roller, toner powder.

Photosensitive Drum:

The photosensitive drum is made of aluminum, and the surface is covered with multiple layers of non-toxic organic photoconductor, also known as OPC drum. Photosensitive drums are most afraid of high temperature, high humidity, and near fire and high light environments. When cleaning the OPC drum, bad touch and scratches will cause permanent damage to the drum surface coating. At present, the life of printer toner cartridges is generally 5,000 sheets, and A3 models are generally about 10,000 sheets.

Magnetic Roller:

The magnetic roller is a metal sleeve with a permanent magnetic core, fixed in the toner bin. When rotating, it adsorbs toner onto it, and adsorbs toner onto the photosensitive drum latent image through the action of electric and magnetic fields.

Magnetic Roller Blade:

It consists of a metal frame and a polyurethane blade. It evenly controls the amount of toner on the surface of the magnetic roller and makes the toner frictionally charged.

Cleaning Blade:

When the photosensitive drum completes a print, the toner image on the drum surface is not 100% transferred to the paper. Therefore, a rubber cleaning blade is used to scrape off the residual toner left over from the previous pattern and store it in the waste toner bin. If the cleaning blade is aged and cannot remove the residual toner, it will adhere to the page below, resulting in irregular black spots and lines.

Primary Charging Roller:

The charging roller itself is applied with both AC and DC voltages, so it has a dual function, that is, charging the surface of the photosensitive drum and clearing the residual potential after one imaging. Damaged or unclean charging rollers and insufficient charging and discharging of the photosensitive drum caused by voltage consumption during operation will cause bottom dust or affect the printing quality.

Toner Powder:

Toner powder is a powdery substance used in laser printers to fix images on paper.