Laser Printer

-Abhijit H Jadhav (Roll no 02)-

Overview

Introduction History Basic Components Laser Printing process Advantages Disadvantages Applications Latest laser printers Bibliography

Introduction

Printers are classified into Impact and non impact printers. LASER stands for Light Amplification by Stimulated Emission

of Radiation. Laser printers uses electrostatic printing process. Laser printers are used to produce high quality images and

graphics.

It is a type of printer that utilizes a laser beam to produce an image on drum.

It uses a non-impact (keys don't strike the paper), photocopier technology.

History Laser printer invented by Gray Starkweather at in

1969 when American Xerox Corporation held a dominant position in the copier market In 1960.

Commercially IBM introduced the first laser printer in 1975 to use it with its mainframe computers.

In 1984, Hewlett-Packard ( HP ) revolutionized laser-printing technology with its first LaserJet, a compact, fast, and reliable printer that personal computer users could afford.

Gray Starkweather

Basic Components

•The drum inside the toner cartridge is photosensitive,(reacts to light)•The laser beam is reflected onto the surface of the drum to create a pattern of charged representing the image of the

page to be printed.

Drum

•The laser beam paints the image of the printed page on the drum. 

Laser

•The process uses very high voltage to charge the drum and transfer and hold the toner on the paper.

Power supply

•The paper path for laser printers ranges from a simple, straight path to the complicated turns of devices•The goal is the same for all these devices-to move the paper from a supply bin to the engine where the image is laid on the paper and fixed

to it

Paper transport

•The primary corona charges the photosensitive particles on the surface of the drum.Primary cornea

•The transfer corona charges the surface of the paper just before it reaches the toner area.Transfer corm

•The fuser makes the printed pages hot.•The toner is melted permanently to the page by apply pressure and heat (between 165 and 180C) to it.Fusing Roller

•It communicates with the OS of printer, and forms the image printed on the page. •This is the motherboard of the laser printer, and it has architecture and components like a PC motherboard.

Controller

Laser Printing Process

Cleaning: Before a new page is printed, any remaining from the previous page are cleared away. The drum is swept free with a rubber blade,

and a fluorescent lamp removes any electrical charge remaining on the drum.

Conditioning: The entire drum is uniformly charged by the primary corona wire. This charge conditions the drum for the next step.

Writing: The laser printer controller uses a laser beam and a series of mirrors to create the image of the page on the drum. The laser beam is turned on and off in accordance with the image to be created on the drum.

Developing: A magnet inside the developing roller attracts the iron particles in the toner. This roller rotates near the drum and the toner is attracted to the areas of the drum that have been exposed by the laser, creating the print image on the drum.

(Toner : the electrostatic image is created by changing the charges on different places. The drum continues to revolve and the toner sticks to the negatively charged places of the text.)

• Transferring: A magnet inside the developing roller attracts the iron particles in the toner. This roller rotates near the drum and the toner is attracted to the areas of the drum that have been exposed by the laser, creating the print image on the drum.

• Fusing: The fusing rollers apply heat and pressure to the toner, which melts and presses it into the paper to create a permanent bond. The rollers are covered with Teflon and treated with a light silicon oil to keep the paper from sticking to them.

Advantages

It is a very fast printer. The printing cost of laser printer is less than inkjet

printer. It has the ability to print the high resolution images

that is 1200 dpi consuming less time.

It makes no noise during printing process.

Their maintenance time span is longer (changing of the toner)

Its efficiency is very high.

Disadvantages

It is very expensive. The maintenance cost is high. Very Bulky and difficult to repair. It has health hazards.(gases like ozone, nitrogen

oxide, carbon monoxide are emitted which are harmful for health.)

Also emit Ultraviolet radiation that can cause eye damage.

Applications

For taking huge printout. For hoardings and banner printings. For taking light fast printouts. For printing books, newspapers etc in huge

industries.

Latest Laser printers (2016)

40 Pages per minute. Maximum storage memory 512 MB. Toner capacity of printing 5000 pages. Capacity of printing 2400 dpi . Wireless printing. Photo printing.

32 Pages per minute. Maximum storage memory 128 MB. Toner capacity of printing 4200

pages. Capacity of printing 2400 dpi . Wireless printing.

 XEROX COLORQUBE 8570DN  BROTHER HL-L8350CDW

Bibliography

https://en.wikipedia.org/wiki/Laser_printing#Color_laser_printers

http://www.sqa.org.uk/e-learning/HardOSEss03CD/ http://www.brainbell.com/tutors/A+/Hardware/Pri

mary_Components_of_a_Laser_Printer http://computer.howstuffworks.com/laser-printer1.h

tm http://www.global-b2b-network.com/direct/dbimage

/50334056/Toner_Cartridge