Modern laser printers require an imaging drum to function properly. The imaging drum, which receives the image or text and subsequently transfers it to paper, aids in completing the ink-to-paper process along with the toner and roller. It performs similarly to the corresponding component in the photocopiers in your office and is also referred to as a drum unit or photoreceptor assembly.
An electrostatic charge is transmitted to the imaging drum through a main charge roller (or corona wire) when an image or piece of text is sent to the printer after being instantly transformed to digitalized lines of colored or neutral dots. The image or text that will be printed is essentially contained in this electrical charge. Just before the new picture or text is transferred, an alternating current is sent to the drum; this current clears away any leftovers from earlier images or texts, but it has no influence on the electrostatic charge.
After passing through a number of mirrors and lenses, the laser inside the printer is finally focused onto the drum. The corona wire’s electric charge on the drum causes the places where there is no charge to draw in the toner when it is used to create the final, printed image. Similar to how magnets and other like forces attract and repel one another, so does this process.
The printing process introduces toner and paper while the image or text is still held on the imaging drum’s surface, resulting in an electrostatic attraction between the drum’s components. Additionally, an electric charge is applied to the paper, guaranteeing the precision of the image’s position as it transfers from the drum to the paper. The last step of transferring the image to paper begins after the toner selects the portions of the drum that are not charged.
The printer instantly transfers the image onto the paper by guiding it over the drum when the toner and drum are in sync. In order to assist in removing the negatively charged toner from the drum, higher-end printers frequently place positively charged rollers on the reverse sides of the paper. This adds another charge and stage to the process. A radiant heat bulb inside the roller activates once the paper has passed over the drum with the toner already adhered, aiding in strengthening the binding between the toner and the paper.