Halftone or Screen
This is a method by which photographs and other images are printed using arrangements of dots to simulate the tones between light and dark. A printing press uses one color of ink at a time; therefore, dots of ink are used to trick the eye into seeing a continuous tone image. With older technology, to accomplish this, a photo was taken through the mesh of a screen to break the image into tiny dots, with today's computer technology the image is converted to dots when scanned. Closer rows of dots and smaller dots mean more dots per inch, leading to a crisper image.
See also dots per inch.
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