Photocopiers...How they work.

How Photocopiers Work – A Clear Picture

Thu, 03/16/2000 - 07:17 — Arlene Martell

The purpose of photocopiers is to create a clear picture – a picture that’s an exact duplicate of the original. Look at the word – photocopy. Photo – picture of. Copy – duplicate. So, as we said, a photocopy is a duplicate of the original picture. But how could an exact copy be created? What kind of technology would it involve? Would it surprise you that the technology behind photocopying is based on two natural phenomena?

The amazing thing about how photocopiers work is the nature of these phenomena. These principles are:

1. Materials of opposite electrical charges attract, and
2. Some materials become better conductors of electricity when exposed to light.

When Chester F. Carlson applied these principles to his work – to find an alternative method of duplicating for the myriad of reports he had to produce – the result was the basis of today’s photocopier, printer and fax machine technology.

The basic principles of photocopying

Chester Carlson’s experiments followed a simple process:

1. A photoconductive surface is given a positive electrical charge.
2. The photoconductive surface is then exposed to the image of a document.
3. The electrical charge dissipates in the exposed areas.
4. Negatively-charged powder that’s spread over the surface sticks to the positively-charged areas through electrostatic attraction.
5. A piece of paper is placed over the powder image and given a positive charge.
6. The negatively-charged powder is attracted to the paper as it’s separated from the photoconductor.
7. Heat fuses the powder image to the paper, producing a copy of the original image.

Today’s copiers follow these principles

Carlson’s electrophotographic process, through much experimentation, has been greatly improved. Modern-day copiers are much advanced from the original model first put out by Xerox in 1948. Let’s look at the electrophotographic process, after it was developed into what we know of today as the photocopier.

• Inside every copier is a light-sensitive surface called a photoreceptor, consisting of a thin layer of photoconductive material that’s applied to a flexible belt or drum. This drum can be charged with a form of static electricity.
• Also inside the copier is toner, a very fine black powder. The drum, when it’s charged with static electricity, can attract the toner particles.
• The drum can be selectively charged; that is, selected parts of it can be charged, thereby attracting toner to only those parts that are charged.
• The sheet of paper gets charged with static electricity and it pulls the toner off the drum.
• The toner is heat sensitive, so the loose toner particles are attached, or fused, to the paper with heat as soon as they come off the drum.

How do you like your copy?

So let’s put all these principles together and see exactly what happens after you put your original on the platen (glass) and close the lid.

After you close the lid, the first thing you see is that bright light passing over your original. This is a similar process to light being let in by a camera lens, projecting the image onto a photoreceptive surface. In the case of the photocopier, the photoreceptive surface is the drum.

The dark, or printed, areas on the original don’t reflect light, and that produces a positive electrical charge. Since positive charges attract, they pull toner, which carries a negative charge, from the toner cartridge, only to the areas that carry a positive charge – the printed areas. From there, heat is applied (which is why your copies are so hot), which fuses the particles of toner to the blank sheet of paper, thereby reproducing your original.

That’s simply it! You get your copy exactly as you want it – exactly what you tell the photocopier to give you.

What about all those parts?

Don’t you wonder how all those moving parts come together at exactly the right time to give you your copy? Let’s see if we can see inside the photocopier to find out what happens when you press that “Start” button.

The first part that comes into play is the corona wire. Its job is to lay down a positively-charged layer of ions on the drum. Then, simultaneously, the light comes on, and the drum begins to rotate. The light reflects off mirrors onto the drum, with the dark areas absorbing the light.

The drum is made out of aluminum, which is a great conductor of electricity. And that makes it the ideal material, because the next step in the process is the addition of an electrical charge, or voltage. And the next part that comes into play is the rollers, which are covered with toner. The toner is pressed onto the roller.

Then the corona wire is activated again, giving the sheet of paper that’ll ultimately be your copy, a positive charge. The sheet of paper then picks up the toner from the drum, and is then sent to the fuser. The fuser consists of heated rollers that melt the toner onto the page.

The copied page is then sent to the collection tray and, voila! You have your photocopy.

The principles of electrophotography are used in many machines today

All this from the dreams and the efforts of one man – Chester F. Carlson – the creator of xerography. Xerography is a unique process that depends on chemical, electrical, mechanical and software know-how. Besides photocopiers, this process is also used in printers and fax machines. The rapid and economical digital printing process most used today produces either one print or hundreds of identical prints in black and white or color. More importantly, the capability of xerography enables on-demand printing of complete documents such as brochures and books. Such on-demand printing can save time, reduce costs, and eliminate document obsolescence, overruns and warehousing.

So you can see, there are many reasons to gain a good knowledge and understanding of electrophotography and its subsequent technology, xerography. If you know what’s going on with your copier, you’ll be able to get the maximum use of its features and benefits. And with that, you’re left with a clear picture.

HONEY it's Medicinal Properties.

Tungsten Carbide..the hardest known alloy

Tungsten carbide (WC) is an inorganic chemical compound containing equal parts of tungsten and carbon atoms. Colloquially, tungsten carbide is often simply called carbide. In its most basic form, it is a fine gray powder, but it can be pressed and formed into shapes for use in industrial machinery, tools, abrasives, as well as jewelry. Tungsten carbide is approximately three times stiffer than steel, with a Young's modulus of approximately 550 GPa,^[2] and is much denser than steel or titanium. It is comparable with corundum (α-Al₂O₃ or sapphire) in hardness and can only be polished and finished with abrasives of superior hardness such as silicon carbide, cubic boron nitride and diamond amongst others, in the form of powder, wheels and compounds.

DomesticTungsten carbide is sometimes used to make the rotating ball in the tips of ballpoint pens that disperse ink during writing.

A tungsten carbide ringTungsten carbide can now be found in the inventory of some jewelers, most notably as a primary material in men's wedding rings. When used in this application the bands appear with a lustrous dark hue often buffed to a mirror finish. The color is more similar to that of hematite than to that of platinum. The finish is highly resistant to scratches and scuffs, holding its mirror-like shine for years. Although it is possible to inlay precious metals, woods, and other materials, these are less scratch-resistant than tungsten carbide.

A common misconception concerning tungsten carbide rings is that they cannot be removed in the course of emergency medical treatment, requiring the finger to be removed instead. Emergency rooms and many full-service jewelry repair shops are equipped with jewelers' saws that can cut through tungsten carbide rings without injuring the hand or finger. An easier way to remove tungsten carbide rings is to use a tool such as a vise, which can be used to shatter the ring.

Many manufacturers of this emerging jewelry material state that the use of a cobalt binder may cause unwanted reactions between the cobalt and the natural oils on human skin. Skin oils cause the cobalt to leach from the material. This is said to cause possible irritation of the skin and permanent staining of the jewelry itself. Many manufacturers now advertise that their jewelry is "cobalt free". This is achieved by replacing the cobalt with nickel as a binder.

LEARN TO ADMIT YOUR MISTAKES

One reason Hitler lost World War II was that he did not fully understand the situation. Bearers of bad news were punished. Soon no one dared tell him the truth. Not knowing the truth, he could not act appropriately.

Many of us are individually guilty of the same error. We do not like to admit to ourselves our mistakes, errors, shortcomings, or ever admit we have been in the wrong. And because we will not see the truth, we cannot act appropriately.

Someone has said that it is a good exercise to daily admit one painful fact about ourselves to ourselves.

Look for and seek out true information concerning yourself, your problems, other people, or situation, whether it is good news or bad news.

Adopt the motto – “It doesn’t matter who’s right, but what’s right.”

Admit your mistakes and errors but don’t cry over them. Correct them and go forward. In dealing with other people try to see the situation from their point of view as well as your own.

REGARDS









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14. The Stonehenge

14. The Stonehenge

The Stonehenge landscape of Salisbury Plain , England , has become a tourist hotspot. But before foreigners with windbreakers and cameras showed up, the area may have been a burial ground and ceremonial den dating back 5,000 years.

13. The Ark of the Covenant..Unsolved mystery.

13. The Ark of the Covenant.
The Ark of the Covenant is described in the Bible as a wooden casket, gold plated, made for carrying the tablets of the Ten Commandments. The casket was carried throughout the desert and remained in the Israelite Temple until its destruction by the hand of the Babylonian Empire. Its whereabouts are still unknown, but Hollywood made its own version for ‘Raiders of the Lost Ark.’


The Ark of the Coveanant.

12. Chupacabra..another unsolved mystery

12. Chupacabra

Phylis Canion holds the head of what she is calling a Chupacabra at her home in Cuero , Tex. The strange-looking animal, first reported in Puerto Rico in 1995, apparently has a taste for chicken and goat blood. Although many pictures like the above might prove its existence, biologists assure none such creature exists.

Fountain of youth..another uvexplained mystery!

11. The Fountain of Youth:

Don Juan Ponce de Leon completed Spain ’s claim on America in 1509, and soon after was made governor of Puerto Rico . Six years later, following Indian rumors, he traveled north to the island of Bimini in search of the Fountain of Youth. Bimini turned out to be the peninsula of Florida, and the fountain remained hidden until July 2006, when famed magician David Copperfield claimed the waters on his $50 million Exumas Island (c.) had healing properties

Tagore Memorial Day...From the Hindu

Dated April 26, 1961:Tagore centenary

The Tagore birth centenary celebrations next month would mark the institution of several chairs in Indian universities and the establishment of permanent Tagore memorial theatres in every State. Disclosing this in an interview with newsmen in Madras on April 25, Professor Humayun Kabir, Union Minister for Scientific Research and Cultural Affairs, said the occasion would be celebrated all over the world in a fitting manner. The Annamalai University in Madras State had agreed to institute a Chair for Bengali literature, while other Indian universities would be opening Chairs for History, Philosophy, Banking, etc. The London University was also introducing a Tagore centenary lecture every year. In the United States, six universities had combined to establish a Chair for Indian Studies. Prof. Kabir said that translations of Tagore's works into various Indian and European languages would also be undertaken.

Significance of Mothers day in India and the Far East

Buddha's birthday, Mother's Day celebrated

By Grace Soong

Tens of thousands of believers gathered to celebrate Buddha's birthday, also officially known as Veska Day, along with Mother's Day and the 100th anniversary of the Republic of China on Ketagalan Boulevard in front of the Presidential Office, yesterday.

Guests from around the globe and mothers from all over Taiwan congregated and “bathed the Buddha” in hopes of bringing peace and prosperity to Taiwan and the world through this spiritual gathering.

For the third consecutive year, the celebration of Buddha's birthday took place on Ketagalan Boulevard on Mother's Day. The event was arranged by the Executive Yuan's Council for Cultural Affairs and hosted by Fo Guang Shan (FGS, 佛光山) and the Buddha's Light International Association (BLIA, ). According to the BLIA, over 100,000 attended the event.

Vice President Vincent Siew encouraged the people of Taiwan by discussing Venerable Master Hsing Yun's philosophy of “three goods and five ways to be at peace” (三好五和), saying that doing good things, saying good words, and thinking good thoughts will bring peace within oneself and society. Buddha's teachings are long lasting, just like a mothers' love, Siew said, while wishing for long life for democracy and freedom of religion.

President Ma Ying-jeou, who was not present at the event, called and expressed his blessings for mothers and the spreading of Buddha's creeds to the crowd through a speakerphone.

The event was attended not only by politicians but also ambassadors and officials from Nicaragua, Swaziland, Nauru, St. Christopher, the Philippines, Mexico and various other nations.

Jeffery Huffines, Chair of the NGO / DPI Executive Committee & U.N. Representative for CIVICUS: World Alliance for Citizen Participation, commended the BLIA, which was acknowledged by the U.N. as an NGO in 2003. He also commended its founder Venerable Master Hsing Yun for promoting humanitarian relief efforts.

Huffines encouraged the creation of “a world in which material and scientific development is governed by ethical and spiritual principles that promote the prosperity of people everywhere.” He also commented that Buddha's spirit of compassion and Buddha's timeless teachings could navigate many global problems and serve as a platform, just like the U.N., for global coordination in this materialistic world.

Former Head of the Yamanashi prefecture parliament Fukazawa Toshio also attended the Veska Day event. He brought along a letter from the president of the Japanese Liberal Democratic Party, Tanigaki Sadakazu, who expressed his gratitude to the Taiwanese public for all their financial and spiritual support following the March 11 Japan earthquake.

“Bathing the Buddha” is a traditional Buddhism practice for Veska Day, where believers scoop up water and pour it over the shoulders of a small-scale Buddha. Venerable Master Hsing Yun said that bathing the Buddha is not just to show respect for the spiritual leader — the source of Buddhist teachings, but also to cleanse the impurities within our minds. To pay tribute to Buddha and mothers for the love and warmth they have brought this world, Hisng Yun said, is the reason Veska Day is celebrated. “May Buddha bless you all,” he said.

Despite the heat, followers of Buddha, including mothers who were over 100 years of age, waited patiently in line for their turn to bathe the Buddha at the end of the ceremony