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 

C

leaning the drum 

C

harging (conditioning) the drum 

W

riting the image to the drum 

D

eveloping the image 

T

ransferring the image 

F

using 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  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

 Blotchy print  Spotty print

Problems

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