Category Archives: Office Evolution

A Simple Guide to the Plotter

The plotter is a form of computer printer used for wide-format printing applications.

Wide format printing is a requirement when one looks to produce hard copies of designs, drawings, maps or similar such items that may have been generated through vector graphics via a computer or other digital source.

Plotters and modern wide format printers are often essential pieces of kit for many different industries and sectors such as graphic designers, architects, engineering, construction or mapping; among many others.

The Traditional Pen Plotter

Pen plotters really began to come into prominence with office printing and designers towards the end of the 1960s and into the 1970s, pioneered by companies such as Hewlett-Packard.

Traditionally plotters operated by use of an automated pen system within the machine, the pens working to a programme to copy the vectors of the computer-generated design. They provided an effective and efficient method of producing hard copies of large or wide format drawings, with the ability to manoeuvre over the paper to draw intricate and complex shapes, lines and colours.

Of course, in comparison to today’s modern wide-format printers (inkjet or LaserJet for example) these plotters were a pretty slow and cumbersome piece of equipment. They were limited by space and design to the number of colours they could possess while there were practical issues with their use such as ensuring pens didn’t run dry of ink.

Despite this plotters were still considered vital for printing requirements due to the fact that they could, even the 1970s vintage, produce high-resolution drawings. In addition, they were also, until the mid-1980s the only real source of attaining a colour hard copy of computer generated imagery.

Plotting an Evolution

Many of the original plotters were designed with a flatbed over which pens were mounted to a travelling bar which would move across the bed, the pens moving according to the vector graphics in order to draw the required shapes onto the paper.

These plotters were effective in their overall quality but slow in operation as well as being bulky and heavy in general use.

Moving into the 1980s plotters however began to evolve, moving towards the modern printers we use today. This evolution included the introduction of ‘grit wheel’ mechanisms which eliminated perforations at the paper’s edge, as factor which, as much as anything, increased the aesthetic quality.

The evolution would continue with the introduction of paper moving printer / plotters with single sheets of paper being fed through a ‘paper pinching’ device in the machine. This moved the plotters away from the old flat-bed design and onto the path that would lead to the printing and plotting machines we see in our offices and workplaces today.

Modern Office Plotters

Today we see a range of different machines which offer digital printing solutions similar to the old style pen plotter.

Machines such as the Hewlett-Packard range of wide-format plotters which can be easily installed into an office or workplace and provide a fast and efficient way of hard copies of computer generated drawings, designs, paperwork and plans.

The Hewlett-Packard Design Jet for instance can produce high resolution colour prints up to four times faster than previous plotter devices whilst maintaining high line accuracy and lower running costs by efficient use of both energy and ink. This evolution in the technology of plotters and wide-format printing means that more and more offices are in a position to handle their own printing and copying requirements in a cost effective and straightforward fashion without the associated costs and hassles of large volume outsourcing.

The History of Printing – Lithography

Lithography is a method of printing that dates back to the late 1700s. Developed by the German actor, Alois Senefelder as a means to publish scripts cheaply, the technique is founded upon the principle of oil and water repelling.

Early Lithography

The original method of lithography involved an image created by oil or wax upon a smooth stone surface, traditionally limestone.

The stone would then be treated with a mildly acidic gum which would enter the pores of the stone that weren’t protected by the oil based image (etching).

During the printing process the stone would be made wet from water, before an oil-based ink was applied. The etched areas would retain the water, repelling the ink which would adhere only to the oil-based image on the stone.

The inked image would then be transferred to a blank sheet of paper, which would give you the printed image on a page.

Senefelder first develop the process in 1796, continuing to master it into the nineteenth century with a vision that perfecting a multi-coloured form of lithography would allow for accurate re-prints of major works of fine art.

The process was taken on and developed further by Godfroy Engelmann who devised the process of chromolithography in 1837. This new version of the technique involved each colour requiring its own stone, the image being pressed with each stone in turn.

Lithographic techniques would subsequently find favour into the mid-1800s with the British Army for instance, seeing the technique as a means to cheaply mass-produce military drawings and maps during the Peninsula War.

Modern Lithography

Versions of lithography are still used to this day; often still in the producing of maps, drawings, posters or the re-production of artwork.

Furthermore, most types of text based publication – books and magazines, will be produced using what is known as offset lithography.

In this modern format, stone has been replaced by a modern printing plate of aluminium or similar material which is given a brushed texture and covered in photosensitive emulsion. A photo negative of the image required for printing will then be brought into contact with the emulsion and exposed to ultraviolet light.

This process produces a reverse image of the photo negative, in other words, a replica of the original image. The image is then transferred to a cylinder in the press and dampened by water. Similar to the traditional lithography techniques, the emulsion on the image areas repels the water, attracting instead the ink later applied.

The image is then transferred further to another cylinder, this time covered in a rubber blanket, to allow the image to dry out. Paper is then fed through this cylinder and a counter-weighted cylinder, upon which the dry image is impressed.

Lithography and Art

Whilst the technique is still used as a commercial process, albeit in ever more digitised forms, lithography as a form has been used throughout the years as a means of printing by some of the world’s major artists – much as Senefelder suggested it might.

Artists in nineteenth century France used the process to produce limited edition prints of their work, with Manet, Degas and Toulouse Lautrec exponents of the craft.

The form continued into the 1900s with notable names such as Chagall and Picasso creating many of their works directly onto Lithographic stone with the printing process itself becoming an ever more integral component of the creation of the work; lithography taking its place as a technique of fine art.

Chester Carlson – Father of Photocopying

Inspired by the likes of Thomas Edison and in search of a way to escape financial hardship, Chester Carlson had long held onto the idea of becoming an inventor.

With his development of the electrophotography process, he would achieve his wish and make a significant mark upon the world.

Growing Up

Born in Seattle, Washington in 1906 Carlson had to grow up quickly. With little household income due to illness of both parents, he was required to earn a wage from a young age. By thirteen he was major provider for his household, fitting work into his days before and after school.

In school his interests seemed to gravitate towards science and pursuits into graphic design, in particular from a publishing perspective – the idea of producing print copies of documents and text a captivating concept for the young man destined to change that industry forever.

As a high school student he developed a handcrafted newspaper, This and That, while, at the same time, taking an after-school job at a professional printers. Trying to publish his magazine using the traditional methods available to him at the printers was laborious and Carlson grew frustrated by the task.

The seed of his idea for a new way of copying was born.

The Zest for Invention

Carlson worked tirelessly to enable himself a place at University, finally graduating with a degree in Physics in 1930.

His mother had died a few years earlier and his father was, by now, too sick to work. Carlson was desperate for a way out of poverty, at a time when the world was plunging headlong into depression. The idea of a developing some kind of invention seemed like a good way to climb out of the economic mire.

Carlson managed to find work as a research engineer with Bell Laboratories in New York City. Within a year he had moved into the patent department. During his time there he continued to work on ideas of his own; returning always to his passion for printing and his scientific background.

In 1933 Carlson was fired from Bell but, despite the continued depression, he was fortunate to not be out of work for too long. Within two years he had managed to get a job as Head of the Patent Department with P.R. Mallory (who would later become a division of Proctor & Gamble).

By his own admission, however, this kind of office existence didn’t suit him. His drive was for creation invention as a means to financial freedom and personal achievement.

Repeatedly he came back to the notion of creating a means to easily produce exact copies of documents and text.

Developing Electrophotography

Through his own experiences in printing and his background as a physics major, Carlson began to develop the idea of creating duplicates via a process of electrostatic charge – using light and ink to attract to positively charged areas of paper.

In October 1938 Carlson had his breakthrough – his invention worked and the world’s first modern photocopier was born.

The problem at the time, however, was that nobody seemed particularly interested!

Battle Memorial and the road to success

Over the next six years, Carlson saw more frustration head his way as he tried to sell the concept to the major companies such as IBM, all of whom declined.

Then, in 1944 and on the point of giving up, his invention caught the interest of the Battle Memorial Institute in Ohio. They agreed to fund further research, to help with development and to seek out interested parties for the idea.

In December 1946 they finally secured a deal. The Haloid Company were already making copying devices and signed an exclusive rights deal to use Carlson’s idea.

Over the next fifteen years the process was developed into workable machines.

Haloid would become Xerox, Carlson found his fortune and the age of the photocopier was born.

Ever Wondered How A Photocopier Works?

Most of us have, at some point, used a photocopier – whether at the office or other place of work, at the library, university or school.

Maybe you were that kid in class who could never stop talking and had to spend playtime photocopying all the Geography hand-outs!

It’s a simple task isn’t it?

From the user’s point of view, there’s really nothing to it.

  1. Open lid
  2. Put your document (face down) onto the glass plate inside
  3. Close lid
  4. Select how many copies you want made
  5. Press Start.

And then the magic happens.

We hear the machine whirr into action, a light moves mysteriously beneath the lid and moments later exact replicas of your document slide gracefully from within – perfectly printed and luxuriously warm to the touch.

But what are these wondrous powers operating inside?

Contrary to popular belief, the process of photocopying is not a mystical act of wizardry nor some magical conjuring trick.

The reality is that it all boils down to good old fashioned science.

In fact, the basic principle behind the workings of a standard photocopier is that of static electricity (electrostatic force).

Perhaps you remember physics lessons from school where you might have rubbed a balloon on a woollen sweater. How the balloon would then react, suddenly blessed with the power to stick to a wall or the top of your head. Or indeed, playing around with the literally hair-raising Van Der Graaf Generator, which would send tingling charges onto your hands when you touched it, making your hair stand on end as the charge passed through your body?

What you witnessed with these experiments was the principle of electrostatic attraction – two forces with opposite electrical charges being attracted to each other.

And it is this same principle which is at the heart of the photocopying process.

So how does an electrostatic force create exact copies of documents and images?

Within the photocopier there are numerous components including:

  • A drum or belt made from photoconductive material
  • A High Voltage Conducting Wire
  • Toner – a dry powder substance
  • A bright lamp
  • A lens.

Having placed our document face down on the glass plate in the photocopier and closed the lid, we then press the start button, which sets into motion the process, as follows:

  1. The high voltage wire creates a positive electrostatic charge across the drum or belt of the photocopier
  2. At the same time, the lamp (its beam extremely bright) passes over the document.
  3. The areas on the paper which contain content (words, images etc) are darker than the blank areas – these dark areas absorb the light from the beam while the light is reflected onto the drum or belt from the blank areas on the paper.
  4. The reflected light hits the drum and forms electrons which neutralises the positive charge in those areas.
  5. The dark areas (the areas with content on the paper) are not reflected and therefore those corresponding areas on the belt or drum remain positively charged.
  6. The toner, which is negatively charged, passes over the drum or belt, being attracted and adhering to the areas still positively charged, thus filling in the areas of content (image or words)
  7. A blank sheet of paper is then passed across the wire, itself becoming positively charged, drawing the toner from the drum or belt and onto its surface.
  8. The paper is then heated so the toner becomes bonded to the surface before being dispensed out into the world.

And hey presto! A perfectly replicated copy of your document.