*NEWS*TODAY’S COPIERS…..PRINTER-SCANNER

Toner News Mobile Forums Latest Industry News *NEWS*TODAY’S COPIERS…..PRINTER-SCANNER

Date: Wednesday May 5, 2004 10:25:00 am
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    <FONT color=blue><FONT face=Times size=6>Today’s copiers more of a hybrid printer-scanner</FONT><BR><BR></FONT><FONT face=”Times New Roman, Times, serif”><FONT color=blue size=3>In The beginning, photocopying was all done with smoke and mirrors. </FONT>
    <P></P><FONT color=blue size=3>Fortunately, today’s copiers keep the smoke to a minimum. </FONT>
    <P></P><FONT color=blue size=3>Frank Romano, professor of digital printing at the Rochester Institute of Technology, remembers a time — some 40 years ago — when every photocopier had a fire extinguisher nearby. </FONT>
    <P></P><FONT color=blue size=3>The paper, he said, would occasionally catch on fire. Romano never actually saw a full-blown fire, but he did retrieve a lot of burnt documents from the early Xerox machines he serviced. </FONT>
    <P></P><FONT color=blue size=3>”You could smell the charred paper inside the machine,” he said. </FONT>
    <P></P><FONT color=blue size=3>Nowadays, of course, paper is far more likely to get jammed than charred. Invented in the 1930s, photocopiers are still highly complex machines based on the science of light and electrostatic charge. But many of the components have been greatly improved over the years. </FONT>
    <P></P><FONT color=blue size=3>In fact, some argue that those changes are so substantial that the machines made aren’t photocopiers at all. They’re more like a hybrid between a scanner and printer. </FONT>
    <P></P><FONT color=blue size=3>”As of about two or three years ago, there isn’t a copier in the world that should be called a <I>photo</I>copier,” Romano said. </FONT>
    <P></P><FONT color=blue size=3>The imaging expert makes the distinction because, unlike modern copiers, old-fashioned machines used light rather directly to create an image. </FONT>
    <P></P><FONT color=blue size=3>Rocco Lapadula, manager of technical support for Canon Canada, said that in a traditional photocopier, the light that illuminates the image is sent through a series of lenses and bounced off mirrors. Ultimately, that light lands on a spinning cylinder. </FONT>
    <P></P><FONT color=blue size=3>The cylinder, or drum as it’s usually known, is specially made so that the outside is sensitive to light. Wherever light strikes the cylinder, the electrostatic charge changes. In this way, a pattern of charges that corresponds to the original document is formed on the drum. </FONT>
    <P></P><FONT color=blue size=3>Modern copiers also begin by illuminating the image and bouncing that light off a mirror, Lapadula said. But the light doesn’t travel very far before it is captured by a special component called a charge-coupled device. The CCD digitizes the pattern of light and shadow that represents the original image. Once the image has been digitized, it can be altered, e-mailed or posted to the Internet, simply by transferring it to a networked computer. </FONT>
    <P></P><FONT color=blue size=3>Printing the image on to a piece of paper requires a few more steps, however. </FONT>
    <P></P><FONT color=blue size=3>First, a laser controlled by the CCD shines on to the photosensitive drum in all the right places so that an image made up of electrical charges is produced on the drum’s surface, just like it was in the old days. Imaging experts call the image on the drum an electrostatic latent image. </FONT>
    <P></P><FONT color=blue size=3>Turning the latent image into a real black and white copy requires the addition of toner. The toner is added via a second cylinder called the developer. Toner on the developer is charged via friction between the developer and a blade-like component, just before it reaches the drum. The charged toner then sticks to the oppositely charged parts of the drum. (Sometimes the toner is charged positive, sometimes negative — it all depends on the composition of the drum itself.) </FONT>
    <P></P><FONT color=blue size=3>The next step is transferring the toner from the drum to the paper. Again, it’s all about opposites attracting. As the drum rolls over the specially-charged paper, the toner jumps off the drum and onto the blank page. </FONT>
    <P></P><FONT color=blue size=3>”At this point, the toner would be easy to smudge because it’s only being held on by charge,” Lapadula said. </FONT>
    <P></P><FONT color=blue size=3>To ensure the toner is fixed on to the paper, the paper is squeezed between two hollow, rubber rollers that have heat lamps inside. </FONT>
    <P></P><FONT color=blue size=3>”As it approaches, the heat melts the toner and the pressure of the rollers pushes it into the paper,” he said. </FONT>
    <P></P><FONT color=blue size=3>Once the picture has been transferred any remaining toner is automatically cleaned off the drum so that it’s ready to receive the next latent image. </FONT>
    <P></P><FONT color=blue size=3>Four-colour copiers use basically the same process, but four times over. Many machines have four drums and four developers: one set each for cyan, magenta, yellow and black. Others have one drum and four developers that butt up against the drum one at a time. </FONT>
    <P></P><FONT color=blue size=3>That’s how things work at the office anyway. It’s a different story altogether for the average home copier. Typically, those machines use inkjet technology and ink instead of toner. </FONT>
    <P></P><FONT color=blue size=3>In such a machine, the print head consists of nozzles with tiny holes. Each nozzle has a heat element that can go from hot to cold very rapidly. That change in temperature results in a change in pressure that causes ink to shoot out the nozzle in little blobs, Lapadula said. Printing an image is a simple matter of controlling the pressure of the nozzles so that the blobs of ink shoot out at the right time as the paper moves along. </FONT>
    <P></P><FONT color=blue size=3>”If you’re printing a lot, it’s more cost-effective to use a laser copier,” Lapadula said. </FONT>
    <P></P><FONT color=blue size=3>Photocopiers are often cited as the reason why the paperless office never materialized. The Internet made it easy to send and receive files, but copiers made them remarkably easy to duplicate too. </FONT>
    <P></P><FONT color=blue size=3>Romano believes, however, that the paperless office — or at least the near-paperless office — might still come to pass. </FONT>
    <P></P><FONT color=blue size=3>”The word copying will exist for a long time,” he said. But scanning will really take over. </FONT>
    <P></P><FONT color=blue size=3>That scanning might be done on a photocopier, but the printouts won’t be in high demand once people get used to using their office copier to convert paper files to digital records. </FONT>
    <P></P><FONT color=blue size=3>”When you think about it, we’re only copying things we have no digital file for,” Romano said. “Over time I think you’ll see more electronic files being moved around rather than hard copying.” </FONT>
    <P></P><FONT color=blue size=3>That would be good news to anyone who’s ever dislodged a troublesome paper jam or found their monthly report ablaze inside the big, beige box.</FONT></FONT>

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