Laser Printer.

Laser Printer.

1 - The PC operating system or a program sends signals to the laser printer to determine where each point of the toner printing will be put on paper. The signals can be of two types - a simple ASCII command or any
page description language. (See How They Work and Vectorial Bitmap Fonts.)



2 - The processor instructions printer quickly activate and deactivate a laser beam.

3 - A rotary mirror deflects the laser beam so that it draw a horizontal line on the surface of a cylinder known as cartridge organic photoconductor (OPC acronym of Organic Photoconducting Cartridge), usually called
Only cylinder.
The combination of activation and deactivation of the laser beam by moving the direction of the beam on the cylinder makes several tiny dots of light to create a line on the surface of the cylinder.
When the laser firing end of the light spots on the length of the OPC drum turns - typically to 1/300,
inch in most laser printers - laser and get to work with the next line of points.

4 - At the same time as the drum starts rotating, a series of gears and bearings pulling a sheet of paper to
Printing module by a mechanism known as paper feeder (paper train). This, in turn, pulls paper
over a wire that transmits electrically charged static energy to the role. The load can be either positive
negative, depending on the design of the printer. In this example we assume that the load is positive ..

5 - At the place where each point of light reaches the drum, the negatively charged film - usually oxide compound Zinc and other material - located on the cylinder surface, altering its charge for the dots having the same charge the electrical sheet. In this example, the light would change the charge from negative to positive.
Each positive charge then mark a point that will be printed if necessary on paper in black (see note below for
more information about printers that print in black). The areas of the drum that are not touched by the laser beam retain their negative charge and result in white areas in the final print.

6 - more or less in the middle of the rotation of the cylinder, the OPC comes into contact with a tray containing a black powder called toner. The toner in this example has a negative electrical charge - the opposite of the loads generated by the cylinder through the radius laser. Because the particles opposing static charges attract. fixing the toner on the drum small dots in which the laser beam created load.

7 - As the cylinder continues to rotate, it presses against the paper sheet being pulled by paper feeder. Although the electric charge of the paper is the same cylinder generated by the laser beam, the load of the paper is increased, pulling the toner from the drum onto the paper.

8 - The rotation of the cylinder near the surface of a thin wire known as corona wire (corona wire). He has this name because the electricity passing through the wire generates a ring or crown, around, with a positive charge. The corona returns negative charge to the entire surface of the cylinder, so that another page can be drawn on its surface by the radius laser.

9 - Another set of ball bearings push the paper into a mechanism known as part of the fusion system. There, the Heat and pressure permanently attach the toner to the paper pressing and melting the wax part of the toner. And the heat of fusion system which causes the paper out of the printer heated.

10 - The paper feeder pushes the paper out of the printer, usually with the printed side facing down,
the page order right impression tray.

Note - In the above description, the electrical positions in all situations can be reversed with the same result. The method described here is valid for most printers that work with the Canon print module, as the models of Hewlett-Packard, among standard laser printers. This recording method is known as black, for each fixed point the cylinder through the laser printer marks a location that will be printed in black. However, there is a method.
Alternatively, in which a laser produces quite different results. 0 Another method, used by the print modules
Ricoh is known as blank recording, because all the places hit by the laser beam end up owning a load
equal to the toner - toner is attracted to areas not affected by the light beam. Printers with blank recording
generally produce black areas darker and with writing in black are more perfect in details.

Source: Evolution of Computers