The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Aug. 29, 2000

Filed:

Dec. 08, 1997
Applicant:
Inventor:

Yuji Tabata, Higashiyamato, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ; H04N / ;
U.S. Cl.
CPC ...
358-19 ; 358457 ; 358460 ; 358535 ;
Abstract

A ROM in the control circuit of a color printer stores a threshold matrix. The individual elements of the threshold matrix correspond to print dots, the number of which is X.times.Y and which form 1 pixel in the original image. Values t (x, y) which are integral numbers not less than 0 are assigned one to each of the individual elements in a predetermined order. Using the threshold matrix, the CPU of the control circuit creates mask patterns for representing halftones. A value of 1 is subtracted from the tone number allotted to the tone of color of a pixel in an image to be printed, and the resultant value is substituted for a variable G. When a gradation for image data representing the pixel is given as 'g', the condition required for setting ON (transferring toner to print) the dot specified by the coordinates (x, y) in the pixel in the case of the gradation 'g' is expressed by the following formula (6):


Find Patent Forward Citations

Loading…