Laser Printers Objectives Know the Six Steps of the Laser Printing Process Know the Components of a Laser Printer How to Troubleshoot a Laser Printer

The Laser Printing Process The physical side of the process The electronic side of the process

The Physical Side of the Laser Printing Process Laser printers perform the printing process in a series of steps Cleaning the drum Charging (conditioning) the drum Writing the image to the drum Developing the image Transferring the image Fusing the image

Six Steps of the Printing Process

Cleaning of the Drum This is were the printing process begins Photosensitive drum must be physically and electrically cleaned Rubber Cleaning Blade Erase Lamp

Charging the Drum Primary Corona wire is used Uniform Negative Voltage 600 to 1000 volts

Write the Image A Laser supplies a positive charge to the drum that is the image of the print job

Develop the Image The toner particles are negatively charged and are attracted to the positive charged areas on the drum This creates the print image on the drum

Transfer the Image The image now must be transferred from the drum onto the paper The transfer corona puts a positive charge on the paper The negatively charged toner particles are transferred to the paper

Fusing the Image The toner is mostly composed of plastic The paper with the image passes between two rollers A heated roller coated with a nonstick material A pressure roller

Print Job Completed Static Charge Eliminator Printer Ejects the Printed Copy Process begins again

Components of a Laser Printer Critical Components of a laser printer are the (continued) Transfer corona Fuser assembly Power supplies Turning gears System board Ozone filter Sensors and switches

Components of a Laser Printer Components inside a laser printer

The Electronic Side of the Laser Printing Process A raster image is a pattern of dots Laser printers use a laser to “paint” a raster image on the photosensitive drum It uses a chip called the Raster Image Processor (RIP) to translate the raster image sent to the printer into commands to the laser

The Electronic Side of the Laser Printing Process The RIP needs memory (RAM) in order to store the data that it must process A laser printer must have enough memory to process an entire page

Troubleshooting a Laser Printer Maintenance Problems

Maintenance The rubber guide rollers of the laser printer can be cleaned with a small amount of alcohol on a fibrous cleaning towel Printer maintenance kits help to assure the continuing reliability of LaserJet printers

Maintenance Replacing certain components of the laser printer periodically ensures a long, healthy life for the printer Following the manufacturer’s maintenance guidelines also helps to ensure years of trouble-free, dependable printing from the laser printer

Problems A user can encounter the following problems when working with laser printers: Blank paper Dirty print outs Ghosting Vertical white Lines

Problems Blotchy print Spotty print

Troubleshooting a Laser Printer General troubleshooting issues that crop up with laser printer are: Print jobs never print Print job that comes out in a strange size Misaligned or garbage printouts Problems sharing multiple printers Consumables and crashes on power up

Components of a Laser Printer The critical components of a Laser Printer are the: Toner Cartridge Photosensitive drum Erase Lamp Primary Corona Laser Toner