Non-uniformity correction for LED printhead in electrophotograph

Incremental printing of symbolic information – Light or beam marking apparatus or processes – Scan of light

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Details

347237, B41J 247, B41J 2435

Patent

active

056661509

ABSTRACT:
A method and apparatus for calibrating a gray level recording printhead having a plurality of light-emitting recording elements is described. In the calibrating method a light intensity of each recording element is measured. The light intensities measured are quantized into M first cells. For each cell an exposure time t (i, j) is determined wherein i is a number representing number of cells and varies from i=1, . . . M and j is a number greater than one representing a number of gray levels. The set of exposure times {t (i, j)} is sorted to remove duplicate times and define a subset of exposure times {t (k)}. A non-uniformity constant value u is associated with each exposure time t (k). Boundaries for plural second cells are defined wherein exposure times, t (k), within a cell are spaced within substantially about the value u from a time b (n) that is calculated from a cell boundary and also falls within the boundaries of each cell. If a number of calculated times b (n) is such that n is different from N, a number representing a number of available exposure times of the printhead, certain of the steps above are repeated with replaced values u until n=N and there is then stored a set of values representing b (n) in a memory associated with the printhead.

REFERENCES:
patent: 4653013 (1987-03-01), Collins et al.
patent: 4831395 (1989-05-01), Pham et al.
patent: 4857944 (1989-08-01), Hart et al.
patent: 4885597 (1989-12-01), Tschang et al.
patent: 4982203 (1991-01-01), Uebbing et al.
patent: 5016027 (1991-05-01), Uebbing
patent: 5025322 (1991-06-01), Ng
patent: 5200765 (1993-04-01), Tai

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