Polaroid's inkless photo printers rely on special 2-by-3-inch (5-by-7.6-centimeter) paper that is embedded with over 100 billion dye crystals to work. As this paper goes through the printer, the print head generates 200 million pulses of heat at different temperatures for varying periods of time [source: Zink]. Each temperature and time period activates a different color -- either magenta, cyan or yellow. Different combinations of these colors can produce any color you need to make a quality picture.
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