| Laser printers have been around for quite a while. But | | | | The first step that is performed by a laser printer is |
| if you ever thought about how these laser printers | | | | known as raster image processing, which encodes |
| actually work, you'd be surprised at how advanced the | | | | some of the source formats like Adobe PostScript or |
| laser technology really is, particularly as there is no liquid | | | | unformatted text into a bitmap which then transfers to |
| ink used in the process. Not only can it output the | | | | the raster image memory. This helps the laser printer |
| same black text that inkjet printers can spray on, but it | | | | accurately replicate the raster image on paper by |
| can also print images on paper without smudging and | | | | sending a continuous stream of dots to the paper. |
| the quality is always surprisingly decent. | | | | The role shifts to the primary charge roller which |
| The whole idea of a laser doing all of these tasks is | | | | projects an electrostatic charge onto a |
| surprising as it is incredible. The whole process relies on | | | | photoconductor unit. This process can be compared to |
| certain scientific principles that are used in a number of | | | | how clothes in the dryer stick together. These charges |
| other devices. Understanding the main components of | | | | are held together on a photosensitive belt or drum. |
| a laser printer can help grasp the whole idea on how | | | | The exposing process immediately takes place |
| these laser printers work. | | | | afterwards and directly involves the laser itself. The |
| Main Components of a Laser Printer | | | | laser takes aim at a polygonal mirror that rotates and |
| Modern laser printers house a charge roller that | | | | channels the beam through several mirrors and lenses |
| projects an electrostatic charge to the photoconductor | | | | reaching the photoreceptor. The rasterised data that |
| drum. A laser is directed on this photoconductor drum, | | | | was created in the first step is used as a reference |
| causing a chemical reaction to take place. This in return | | | | on how the laser draws the data onto the rotating |
| develops a negatively charged electrostatic image to | | | | imaging drum. The laser is precisely aimed at these |
| give way to the toner that does the rest. The toner, | | | | parts causing a reversing charge that attracts particles |
| which is basically a container that contains black or | | | | from the toner. With the basic concept of static |
| coloured powder, transfers some of that powder to | | | | electricity, toner particles simply attract to the affected |
| the rotating drum where the powder accurately sticks | | | | areas designated by the laser resulting to an accurate |
| to any part of the paper that has an opposite charge | | | | output. |
| in order to attract. Parts of the page with the same | | | | As a print operation commences, the paper is taken in |
| charge don't get affected which is how the print output | | | | and pressed against the photoreceptor to transfer the |
| is created. Older printers used a corona wire instead | | | | image. It then uses a fusing process where high |
| of a charge roller. | | | | temperatures are applied to permanently bond the |
| Detailed Process | | | | powder from the toner onto the paper. |
