7-step laser printing process

Processing

The printer receives the print job from the computer and processes the data to build a page image in memory (typically in the printer's RAM).

Charging

• The primary corona wire or primary charge roller applies a uniform negative charge to the photoconductor drum (usually about -600V).

• This prepares the drum for writing.

Exposing (or Writing)

• The laser writes the image by selectively discharging parts of the drum to a lower voltage (around -100V), creating an electrostatic image.

• The areas hit by the laser represent where toner will stick.

Developing

• Negatively charged toner particles are attracted to the discharged (less negative) areas of the drum.

• The latent electrostatic image becomes visible as toner sticks to it.

Transferring

The transfer roller applies a positive charge to the back of the paper, pulling the negatively charged toner from the drum onto the paper.

Fusing

The fuser assembly (heated rollers) melts and presses the toner into the fibers of the paper, permanently bonding the image.

Cleaning

• The cleaning blade or roller removes any leftover toner from the drum.

• The drum is also exposed to an erase lamp to remove residual charge, preparing it for the next page.