The photocopier is an intricate machine, but it works using two fundamental scientific principles.
The core of the photocopier is its spinning drum equipped with a unique photo-conductive coating. The paper is exposed the bright light that will charge the white areas positively while leaving the black parts negatively charged. The drum is then attracted by toner that sticks to it and makes an printed image on the paper.
Xerography
The technology that drives the majority of copy machines is known as the xerography. It’s a process that is dry made using electrostatic charge. It works by applying static charges to an ‘ink’, a black powder called toner. It then uses heat to make them adhere to the paper.
Chester Carlson invented the xerographic method at his home laboratory in 1938. It has transformed our work by making it possible to produce large numbers of copies. The invention of Carlson was initially rejected by some large companies, but he went on to make it one of the most significant office innovations of 20th century.
In a photocopier the sheet of paper that is to be copied gets illuminated by an extremely bright light. In a photocopier the sheet of paper to be copied is illuminated with the very bright light. The printed or marked parts don’t bounce the light back. The result is that electrons on the edge of the drum to diffuse downwards leaving behind a lingering electrostatic image of the paper.
Then, the toner is charged negatively. This is accomplished by sending the ‘ink’ into an electric field that is created by corona wires. The negative toner is drawn towards the electric shadow of the photoconductor and produces an inked replica of the original. A roller is able to give the paper on the other side of a conveyor belt a charge, which draws toner that is positively charged. The toner and paper are then fused with high heat. This gives the copy its permanent appearance.
Photocopying Technology
Photocopiers ‘print’ documents onto papers using an electric charge, rather than ink. The charge is produced through a rotating drum which contains a reservoir containing black powder, also known as toner. Toner and the drum both are charged with different electrical charges. They draw each other. The drum has a coating of a chemical which draws toner particles onto a blank piece paper.
The document that you want to copy can be placed in a slot at the top of the machine. A bright light scans the document looking for dark areas. The scanner’s light reflects off of these dark areas and creates an electric shadow’ of the page that is reflected off of a conveyor belt called a photoconductor.
A photoconductor is the form of a cylindrical object coated with an electroconductive coating. The drum is given positive charge through the laser inside a scanning device or scanner. The drum is also exposed to a reservoir with carbon toner particles which carry an opposite charge. Toner sticks to the exposed drums that are heated before being is bonded to the paper. Static electricity can cause paper to jam if it is still in the copy. This is the reason it’s crucial to clean the surface of the copier frequently.
Photocopier components
The most obvious photocopier components are the glass tray where you put your document and the lamp that casts light on it as well as the drum, which is an elongated conveyor belt that is coated with a special photo-conductive substance. The photoconductor that was used in early copiers was a form of the rare metal selenium, and later models used enhanced selenium telluride alloys. This material turns light into electricity by removing electrons from photo-conductive atoms. By shining a bright beam over the original document more light reflects off areas that are white and unprinted than off the black inked areas making an electrical shadow of the initial page the photoconductor.
The optical scanner creates an image that is then passed to the printing section of the photocopier by the RIP. This section also generates static electricity, and employs the same technique as a photocopier. Thue may photocopy hcm prints each line of the document using the drum, which heats to create the ink.
It’s likely that you’ve seen static electricity before. It’s what you experience when you rub a balloon on your clothing and then attach it to the wall. Another trick is the fact that some substances get more conductive as they absorb light (photoconductivity). This is how xerography works and that’s the reason why many modern photocopiers the dependable and high-performance machines that they are.
Electrophotography
The formation of a charge electrostatic on the drum or a different surface is key to photocopying. The charge is generated by corona wires which are exposed to high voltage to create an electrical field between the drum and paper. The negative charges on the paper attract the positively charged toner particles, creating images on the page.
Electrophotography, also known as xerography, is the principle operation that drives all laser and digital copy printers. This process was created in 1937 by Chester Carlson, who worked alongside the Battelle Memorial Institute to develop the technology into a commercial item. He established Haloid Corporation which became Xerox Corporation by 1961.
Electrophotography utilizes two fundamental phenomena: materials of opposite electrical charge draw each other and some materials are better conductors of electricity when exposed to light. Carlson invented a procedure in six steps to transfer an image from one area to another through these phenomenon.
Then, the document is exposed to the photoreceptor. It is typically an especial drum that is coated with a semiconductor material which only conducts in a vertical direction. After placing the document in front of a photoreceptor shining light is reflected onto it. The light bounces off of the white parts of the document, and is transmitted through mirrors to illuminate dark regions. The light reflected passes through the photoreceptor, and releases its electric charge to the illuminated areas. The resultant pattern of electrical charges that is formed on the photoreceptor’s surface is known as a latent image.