In 1969, Gary Starkweather, who worked in Xerox's product development department, had the idea of using a laser beam to "draw" an image of what was to be copied directly onto the copier drum. In the 1960s, the Xerox Corporation held a dominant position in the photocopier market. Gary Starkweather (seen here in 2009) invented the laser printer.
Over the decades, quality and speed have increased as prices have decreased, and the once cutting-edge printing devices are now ubiquitous. Invented at Xerox PARC in the 1970s, laser printers were introduced for the office and then home markets in subsequent years by IBM, Canon, Xerox, Apple, Hewlett-Packard and many others. Laser printing differs from traditional xerography as implemented in analog photocopiers in that in the latter, the image is formed by reflecting light off an existing document onto the exposed drum. As with digital photocopiers, laser printers employ a xerographic printing process. The drum then selectively collects electrically-charged powdered ink ( toner), and transfers the image to paper, which is then heated to permanently fuse the text, imagery, or both, to the paper. It produces high-quality text and graphics (and moderate-quality photographs) by repeatedly passing a laser beam back and forth over a negatively-charged cylinder called a "drum" to define a differentially-charged image. Laser printing is an electrostatic digital printing process.
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