Mitsubishi has developed a prototype inline print quality control system for commercial web offset presses, dubbed the “MAX DIAMOND EYE,” and will unveil the new system at IGAS 2007 installed on a Mitsubishi DIAMOND 16SSS web press.

Previously, Mitsubishi and The Yomiuri Shimbun jointly developed an inline print quality control system, known as DIAMOND EYETM, for the company’s line of double width newspaper offset presses. In 2006, the DIAMOND EYETM received a technology award from the Japan Newspaper Publishers and Editors Association.

Since then, Mitsubishi has been aiming to expand applications of the system to its line of commercial web offset presses, however, due to the significant differences in color reproduction of inks, web substrates and overall printing quality demands, practical application has been difficult.

The prototype MAX DIAMOND EYE basically follows the same system configuration as for newspaper printing, but includes a newly developed image processor containing a preprogrammed database of calibrations on different ink and web combinations in order to match different color reproductions.

MAX DIAMOND EYE realizes full automation of color matching without the use of color patches by calculating and setting the printing target based on printing characteristics of the press, such as a dot gain, and then comparing the image data received from prepress with the actual image data read by the image sensor in the press. The system consists of a PPC Server, IPC II+, operation console, control device, and image sensor.

The PPC Server receives CIP3/4 image data from the prepress and converts it into control data that is then stored. The stored control data is transmitted to the control device from the PPC Server via the IPC II+. Once printing begins, the control device compares the actual image data provided by the image sensor with the stored control data and automatically performs control and check.

MAX DIAMOND EYE Main Functions:

1. Color Density Control
   Target density of C, M, Y, and K is calculated for each inking area based on image data and controlled at the startup of printing. Therefore, color matching is automatically initiated without input from the press operator. As an additional control method, the operator can set the target density, which may prove more effective for controlling specific colors or specific image parts.


2. Printed Web Surface Check
   This function detects ink spots and oil splattering by comparing actual printed image density with preset (proof) density in pixel. Defective prints are automatically removed by signal transmission to the delivery carrier.

MAX DIAMOND EYE Standard Specifications (IGAS Exhibit)
Printing Speed	1,200 rpm (10.9m/sec) for 546 mm cutoff
Density Control Function	Patchless Two control modes: 1. Startup control: within target density of ±0.20D for each color 2. Good copy control: within target density of ±0.10D for each color
Printed Web Surface Check Function (Minimum defect detection diameter)	4mmΦ for each color (In case of blank sheet, density 1.0D)
Required Systems	PPC Server, IPC II+ (online connections)