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.
Patent No.:
Date of Patent:
Oct. 24, 2000
Filed:
Oct. 14, 1997
Christopher S Magirl, San Diego, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
Large, overlapping 'mega-dots', placed on small, high resolution pixel locations, are used in high quality monochrome imaging to preserve information to the micro, or pixel, level, thus avoiding the need to use micro-sized droplets. By using multiple passes and multiple pens with different levels of gray ink, one may build a single monochrome 600 dpi (dots per inch) pixel with the composite gray of those droplets at that pixel location as well as the neighboring locations. With careful print modes and multiple passes, one can produce several levels of gray at a particular pixel location. The biggest advantage of using multipixel dots is that the sensitivity to trajectory errors is significantly reduced. For example, a dot that is 1/150.sup.th inch diameter is almost indifferent to a 1/1200.sup.th trajectory error. Even a relatively large 1/600.sup.th inch error has little impact on the large 1/150.sup.th dot (25% error). In reducing the sensitivity to trajectory errors, overall imaging errors, such as banding, can be reduced, and overall image quality enhanced. Optimally, the large dots have a diameter that is about three to five times the pixel size, providing an overlap of three to five dots, respectively.