The desired amount of reduction for coring depends on line width and overall nominal colorant level. Coring, defined as a process whereby the colorant level is reduced in the interior of text or characters, is a remedy for these shortcomings. However, this can result in undesired color shifts and the introduction of halftone texture in light regions. A conventional approach to reduce toner overdevelopment is to restrict the color gamut of printers.

Toner scatter caused by toner overdevelopment in color EP laser printers can significantly impact print quality. Since text and lines are indispensable to print quality, many studies have proposed methods for measuring these print quality attributes. Thus, the print quality of color EP laser printers is more important than ever before. The use of color electrophotographic (EP) laser printing systems is growing because of their declining cost. Finally, we describe the design of a set of instruction pages that walk the customer through the process of identifying on the test pages PQ defects that can be remedied by customer replaceable parts. For the constant tone fields on the test page, we consider the specific case of designing halftone patterns that will not show fine pitch banding that is within specification.

The PQ test pages should be designed to not reveal such defects to the customer. We introduce the concept of imperfections within specification which are PQ defects that fall within the PQ specification of the printer. We then incorporate these test features into a set of test pages for a specific print mechanism architecture.

We design test features which clearly reveal the common PQ defects that occur with color laser printers, such as failure of color plane registration, ghosting, and repetitive artifacts. We develop a set of test pages for the customer to check the condition of a printer without using any other tools. A print quality (PQ) test page is a diagnostic tool which is designed for accurate and effcient diagnosis of PQ defects.

Test print laser printer