Theory-13 :- Laser Printing Process

 

Laser Printing Process

There Are Following Steps for Laser Printing Process

NOTE *easy way to remember this is CLEAN CARS WILL DRIVE TO FAST

1. Cleaning – The Photosensitive drum is cleaned before it can take on a new image
2. Conditioning or Charging – To make the drum receptive to new images, it must be charged. The EP drum is given a negative charge by the primary corona wire around ‐600 and ‐1000 volts
3. Writing ‐ A laser beam is use to write to the EP drum causing dots on the drum to lose some of the negative charge and become relatively positive charge
4. Developing ‐ A toner is transferred from the toner cylinder to the EP drum by attracting the area of the drum that has a   Relative positive charge
5. Transferring ‐ The transfer corona wire puts a highly positive charge on the paper once the paper has a positive charge the negatively charge toner particle leaps from the drum into the paper
6. Fusing ‐ The compression roller and fusing roller press and melts the toner into the paper the fuser gets very hot Laser printers generally follow the following processes to produce a page of print:

• Cleaning Conditioning
• Writing
• Developing
• Transferring
• Fusing

Cleaning Before a new page is printed; any remnants from the previous page are cleared away. The drum is swept free of any lingering toner with a rubber blade, and a fluorescent lamp removes any electrical charge remaining on the drum. Any toner removed in this step is not re‐used but is put into a used‐toner compartment on the cartridge.

Conditioning The entire drum is uniformly charged by the primary corona wire. This charge conditions the drum for the next step.

Writing The laser printer controller uses a laser beam and a series of mirrors to create the image of the page on the drum. The laser beam is turned on and off in accordance with the image to be created on the drum. At the spot where the laser's light contacts the photosensitive drum, the charge is reduced. After the entire image has been transferred to the drum, the controller starts the page sheet through the printer, stopping it at the registration rollers.

Developing A magnet inside the developing roller attracts the iron particles in the toner. This roller rotates near the drum and the toner is attracted to the areas of the drum that have been exposed by the laser, creating the print image on the drum.

Transferring The back of the paper sheet is given a positive charge that attracts the negatively charged toner from the drum onto the paper as it passes. After this step, the paper has the image of the page on it, but the toner, which is held only by simple magnetism, is not yet bonded to it.

Fusing The fusing rollers apply heat and pressure to the toner, which melts and presses it into the paper to create a permanent bond. The rollers are covered with Teflon and treated with a light silicon oil to keep the paper from sticking to them. Your printer will have come with a user manual that should explain the necessary cleaning and maintenance that should be undertaken. On the manufacturers' websites you will find a support section where you can download support details on their products.