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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6 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

12 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

13 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

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)