A variety of form roller—the roller that directly contacts and transfers ink to the printing plate—found in the inking system of an offset press which, unlike conventional form rollers, moves laterally as it rotates. The oscillation of the form roller should be at a rate different from that of the nearest oscillator, a standard ink roller that itself oscillates back and forth. Oscillating form rollers are added to not only further smooth the ink before it is transferred to the plate, but to also help eliminate the press problem known as mechanical ghosting, commonly caused by allowing the image area of the plate to continuously remove ink from the same portion of the roller. (See also Form Roller.)
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