Graphic plotters were invented in the 1950s. During the 1960s and 1970s, companies such as Hewlett Packard and IBM bought out smaller companies to become large-format print industry leaders. Graphic plotters were still in widespread use throughout the 1980s and 1990s. However, progress in the capabilities of laser printers (including size, speed, accuracy, computer compatibility and resolution) led to the decline of plotter use in traditional settings (like architecture and graphic design firms) in the late 1990s.
The first graphic plotters, which were built in the 1950s, used ball-point pens attached to armatures to draw on large, flat pieces of paper. A simple computer controlled a motor to generate the drawing movements. These machines took up several square feet of floor space because the paper had to lie flat. The pens moved slowly (to draw all the details accurately and because the computer processing capabilities were so small). Over time, drum plotters (which used rolls of paper and placed the pens in a housing above the paper) replaced these flatbed plotters.
Plotters print graphic images (including maps, diagrams, blueprints, patterns, schematics and fine art reproductions) that are created using computer aided design (CAD) software programs. The files are usually in a vector format (which uses mathematical information to create images, rather than the pixels used by a raster image). Graphic plotters print up to the equivalent of 1,000 dots per inch (dpi), making them ideal for large, detailed images.
Architects and product designers use graphic plotters to print blueprints, schematics and diagrams. Printing companies often use these machines to create posters or fine art reproductions. During the 1980s, companies attempted to market plotters as the perfect home printer. Plotters for home use never gained popularity because of their slow speed and size.
While inkjet and laser printers create images using dots of ink, graphic plotters print using pens that draw in continuous lines. Graphic plotters tend to take longer to print images because of the image file size, the amount of detail in the images being printed and the size of the print itself. The machine can use inexpensive paper suitable for drafts or acid-free paper suitable for archival-quality prints. Plotters also use different types of ink, with a wide variety of colors and qualities (from draft to archival) available.