Non Impact Printer

Introduction

The modern xerographic process used today was pioneered by Chester Carlson

Chester Carlson developed the first mass produced office copier with the Haloid Company, which later became Xerox.

The first xerographic image

1938 Chester Carlson made the prototype photocopier

First commercial photocopier

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Cost per Page

$0.00

$0.20

$0.40

$0.60

$0.80

$1.00

1992

1996

1998

1999

2000

2001

Year

Uni

ts Color LPColor IJ

HP Printer Cost Comparison

$0

$500

$1,000

$1,500

$2,000

$2,500

$3,000

$3,500

$4,000

$4,500

1992 1994 1996 1998 2000 2002 2004 2006

Monochrome

Color

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Laser Printers

• Interaction of mechanical, electrical and optical technologies

• Use toner, a dry, powdered electrically charged ink

• Performs various steps in printing process

Non Impact Printer

How its works?

Cleaning

The Six Stages of Operation in a Laser Printer include:

Conditioning

Writing

Developing

Transferring

Fusing

Six Steps of Laser Printing

1. Cleaning

2. Conditioning

3. Writing

4. Developing

5. Transferring

6. Fusing

Take place inside toner cartridge

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How a Laser Printer Works

• Cleaning

Drum is cleaned of residual toner and electric charge

• Conditioning

Drum is conditioned to contain high electrical charge

• Writing

A laser beam discharges a lower charge only to places where toner should go

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How a Laser Printer Works

• Developing Toner is placed on the drum where charge has been

reduced

• Transferring Strong electrical charge draws toner off the drum onto the

paper

Takes place off the drum

• Fusing Heat and pressure fuse toner to the paper

Step 1: Cleaning

• The drum is cleaned of any residual toner and electrical charge

Step 2: Conditioning

The drum is conditioned to contain a high electrical charge. This drum assembly is made out of highly photoconductive material that is discharged by light photons.

As the drum revolves, the printer shines a tiny laser beam across the surface to positively charge certain points. In this way, the laser "draws" the letters and images to be printed as a pattern of electrical charges , an electrostatic image.

Step 3: Writing

Step 3: Writing

• Data from PC is received by formatter (1) and passed to DC controller (2) which controls laser unit (3)

• Scanning mirror (4) is turned clockwise by scanning motor

• Laser beam is reflected off scanning mirror, focused by focusing lens (5) and sent to the mirror (6)

• Mirror deflects laser beam to a slit in the removable cartridge and on to the drum (7)