---

---

---

---

Assalamualaikum Everyone
This is @ripon999 from Bangladesh

• Hope Everyone is well.
• I am also well by the grace of Allah.
• Today I have chosen "Technology" among the three contest at "Technology" "Science" and "Computing" by Settem-Bangladeah community.
• So Let's get Started.

---

---

The object that I am going to discuss today about technology is very important and significant among us and its name is "Photocopy Machine"

---

---

🆆🅷🅰🆃 🅸🆂 🅿🅷🅾🆃🅾🅲🅾🅿🆈

A photocopier is a machine that makes copies of documents and other visual images onto paper plastic film quickly and cheaply. Most modern photocopiers use a technology called xerography, a dry process that uses electrostatic charges on a light sensitive photoreceptor to fast attract and then trancefer toner particales onto paper in the form of an image.The toner is then fused onto the paper using heat, pressure or a combination of both.

source

---

---

🅗🅘🅢🅣🅞🅡🅨

Chester Carlson the invetor of photocopying was originally patent attorney as well as a part time researcher and inventor.His job at the patent officce in New York.Carlson used his kitchen for his electrography experiment and in 1938 he applied for a patent for the process. he made the first photocopy using a zinc plate cover with Sulfur.The words "10-22-38 Astoria" Were written on a microscope slide, which was placed on top of more sulfur on under a bright light. After the slid was removed, a mirror image of the words remained.

In 1944,the Battle Memorial Institute a nonprofit organization in Columbus Ohio contracted with carlson to refine his new process. Over the next five years the institute conducted experiment to improve the process of Electro photography.In 1947, Holid Corporation Approached Battelle to obtain a licence to develop and market to copying machine based on this technology.

source

Haloid felt that the work electrophotography was too complicated andvdidvnot have good recall value.After consulting a professor of classical language at ohio State University.Haloid and carlson change the name of process to "Xerography":which was derived from Greek words that meant "dry writting".Haliod called the new copier machines "Xerox Matchine" and in 1948, the word xerox was trademarket.Haloid eventually changed it's name to "Xerox Corporation".

Xerographic copier manufacturers took advantage of a high percived value of the 1960s and early 1970s,and marketed paper that was specially degsigend for xerographic output.Bye the end of the 1970s,paper producers make xerographic runabillty requierments for most ofvtheir office paper brands.

Among the key adventage of photocopiers over earlier copying technologies are their abillity:

• To use plain(untreated) office paper.
• To implement duplex (or two-sided) printing.
• To scan sevaeal page automaticallyvwith with and ADF and
• Eventually,to sort and staple output.
  source

---

---

🅷🅾🆆 🅸🆃 🆆🅾🆁🅺🆂

Charging:

Cylindrical drum is electrostatically charged by a high voltage wire called a corona wire or a charge roller.The drum has a coating of a photoconductive material.A photoconductor is a semiconductor that become condective when exposed to light.

Exlosure :

Abright light illuminates the orginal documents and the white areas ofvthe original documents reflect on to the surface of the photoconductive drum.The areas of the drum that are exposed to light become conductive and therefore discharge to the ground.The area of the drum not exposed to light remain negatively charged.

Developing:

The toner is posetively charged.When it is applied to the drum to develop the image,it is attracted andvstike to the areasvthat are negatively charged ,just as paper sticks to ballon with a static charge.

Tranansfer:

The resulting toner image on the surface of the drum is tranceferred from the drum onto a pice of paper that has an even greater nagetive charge than the drum has.

Fusing:

The toner is melted and bonded to rhecpaper by heat and pressure rollers.

source

---

---

🅕🅞🅡🅔🅝🅢🅘🅒 🅘🅳🅔🅝🅣🅘🅕🅘🅒🅐🅣🅘🅞🅝

Similar to forensic identification of type writers computer printers and copiers can be traced by imperfections in their output. The mechanical tolerance of the toner And paper feed mechanisms banding,which can reveal information about the individual devices Mechanical properties. it is often possible to identify the manufacturer and brands, and in some case,the individual Printer can be identify from a set of known printers by comparing their outputs.

---

---

🅲🅾🆄🅽🆃🅴🆁 🅵🅴🅸🆃🅸🅽🅶

To counter the risk of people using colour copiers to creat counterfeit copiers to paper currency,some countries have Incorporated anti-counterfeiting holograms tiny security stripe makes of plastic and ink that appears to change color as the currency viewed at an angel.Some photocopy matchines contain special software that can prevent copping currency that contains a special pattem.

source

Best regards @ripon999

---

♥Thanks To All♥

---