BlogBits Team brings you some good reading today having paused the flow of posts a bit over past few days.

All of us print loads of document each day on a laser printer, at home and work. Ever wondered how it works, or what’s ‘LASER’ about it? We will see how the LASER printing works in the following post.

The Technology:

A laser beam projects an image of the page to be printed on a charged rotating drum coated with selenium. Photoconductivity removes charge from the areas exposed to light. The charged areas of the drum pick up toner particles electrostatically. The drum then prints the document on paper by direct contact and heat which fuses the ink toner and sticks it on the paper.

Steps in Laser Printing:

The printing process can be broken down into seven steps:

1. Raster Image Processing (RIP): The image to be printed is created in the raster memory during this bit with the help of RIP technology.
2. Charging: This involves projecting a negative electrostatic charge on the drum aka photoconductor unit.
3. Exposing: The drum is exposed to a laser beam which neutralises the negative charge on the drum in the shape of image to be printed.
4. Developing: The negatively charged toner particles, which is dry plastic powder mixed with carbon black or colouring agents are projected on the drum
5. Transferring: Photoreceptor transfers the image on to the paper at this stage. Advanced printers have a roller drum that projects positive charge on the paper, which then pulls the negatively charged toner particles.
6. Fusing: At this stage paper passes through two rollers; a heat roller, which is a hollow tube with a radiant heat lamp in it and a pressure roller, a rubber tube that presses the paper against heat roller, thus fusing the toner to the paper with a combination of heat and pressure.
7. Cleaning: During cleaning, a soft, electrically neutral plastic blade brushes away any excess toner on the photoreceptor and deposits it into a waste reservoir and a discharge lamp removes the charge from it.

Colour Printing:

Colour Laser Printers use CMYK toner cartridges (Cyan, Magenta, Yellow and Black). These are four separate cartridges in the printer. Typically colour printing requires four times the memory of a monochrome print as all the four colour separations are rasterised and stored in memory before printing begins and then transferred and fused on to the paper in a single step.

(Adaptation of a Wikipedia Article)

Related posts:

1. Laser printer toners – Yields quality
2. Differentiate between Ink and toner
3. Toners – beautify the prints
4. InfoTec toner
5. Samsung  toner – The best toner for your printer