Method and apparatus for scanning a receiving medium
AssigneeEastman Kodak Company
InventorsSeung H. Baek, Thomas A. Mackin, Ephraim Pinsky
Life of this patent
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Abstract
A method and apparatus are disclosed for scanning a receiving medium. The apparatus comprises a motor-driven lead screw which is used to advance a print head relative to a receiving medium supported on a rotatable drum. In order to overcome the problem of banding in an image produced by the apparatus as a result of a sinusoidal pitch error of the lead screw, the pitch error of the lead screw is broken up into a random pitch error. In another embodiment, the pitch error frequency is shifted to a higher frequency which is less sensitive to the human eye.
Claims13
A method of scanning a receiving medium to write an image on said medium in an apparatus comprising means for supporting said medium, a scan head movable relative to said medium, means for moving said scan head relative to said medium including a lead screw having a pitch error which adversely affects the image written on said medium, and a motor arranged to drive said lead screw in response to a command signal supplied thereto, said method comprising the step of injecting an error signal into said command signal to variably drive said lead screw whereby adverse image effects are minimized.
Apparatus for writing an image on a receiving medium by scanning said receiving medium, said apparatus comprising means for supporting said medium, a scan head movable relative to said medium, means for moving said scan head relative to said medium including a lead screw having a pitch error which adversely affects the image written on said medium, a motor arranged to drive said lead screw in response to a command signal supplied thereto, and means for injecting an error signal into said command signal to variably drive said lead screw whereby adverse image effects are minimized.
Apparatus for writing an image on a receiving medium by scanning said receiving medium, said apparatus comprising means for supporting said medium, a scan head movable relative to said medium, means for moving said scan head relative to said medium including a lead screw having a pitch error which adversely affects the image written on said medium, a motor arranged to drive said lead screw in response to a position command signal representing a position of said scan head supplied to said motor, and means for injecting an error signal into said position command signal to variably drive said lead screw whereby adverse image effects are minimized.
Dependencies are inferred from the claim text.