Now we can use the Standard Color Management System, however many users can not use well. Because it is difficult for them to understand all of the system. In this paper I explain about the Standard Color Management System and the ICC Profile. In addition I introduce the problems and the solutions about the ICC profile.

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The Color Control System (CCS) is in-line color control system for offset web printing processes. It uses color measurement information to increase the accuracy of color reproduction during the printing process. The CCS automatically searches for, locates, and tracks micro color bars to relate color density information to press operators. It also automatically sends any necessary correction to press ink key control console. The measurement for correction is performed by the patented video densitometer installed in the CCS Scanner on the Scanner Stand at the end of printing process. The CCS has capability to eliminate the subjectivity and inconsistency for color reproduction and to maintain the color densities through the press run. The CCS also provides the functions to monitor the 3-color gray balance, CMY midtone balance, trapping and effect of dot gain. This paper reports color control is quickly becoming both an acceptable technology and to meet customer expectations.

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The expansion of conventional still cameras has provided opportunities for consumers to enjoy new digital imaging. The typical digital-camera system flow in which the image data are captured and transformed to a set of encoded signals is described. Three transformations including an input transformation from scene to a hub-space, a hub-space to a display monitor space, and a hub-space to a printer space are classified and clarified. Requirements for digital still cameras to make good picture quality images are discussed and then compared to those for conventional photographic films. It is stressed that the rendering issue in relation to device characteristics and a picture-taking situation is a key to achieve best image quality.

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Authors have been continuing to investigate the colorimetric characteristics of process color prints and proofs produced under various printing conditions. This paper reports measured data and analyzed results of these data. These results obtained can be summarized as follows:
1) Regarding the 3 color prints, three-dimensional colorimetric values for color patches where their ink values of the one color (e.g. Cyan) are held fixed and others are arbitrary have a planner relationship and lie on a flat plane in the L*a*b* color space.
2) The planner relationship for an ink F (F: Cyan, Magenta or Yellow) can be expressed by the following equation. L*=α_F(F)a*+β_F(F)b*+γ_F (F) where, F is an ink value of Cyan, Magenta or Yellow. Coefficients of α_F (F), β_F (F) and γ_F (F) can be approximated by quadratic functions of ink value F, and their curves of coefficients have almost same form regardless of rendering systems. The mean value of color differences (ΔEs) between measured values and predicted values for specified ink values is less than 4.0 for offset processes, newsprints and proof print.
3) Regarding the 4-color prints, the same relationship as 3-color prints can be observed when F and K values are held fixed and others are arbitrary. When replacement of coefficients α_F (F)→α_F (F+K-F×K-δ_F), β_F (F)→β_F (F+K-F×K-δ_F) and γ_F (F)→γ_F (F+K-F×K-δ_F) is performed, coordinates of Colorimetric values for color patches of 4-color prints have a planner relationship referred to in Result 1) where, the δ_F (additional value) is a small value for correction.
These results made possible to describe the output device profile by simple equations accurately and to provide the gray balance conditions. Moreover, we could obtain the mutual conversion algorithm between CMY and CMYK ink values and the replacement rule between color inks and black ink for UCR and achromatic process by making clear the planner relationship for 4-color prints.

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Liquid crystal Displays (LCDs) have been used for many applications these 20 years. This paper reviews the different kinds of LCD mode in the view of liquid crystal materials. The relation between the LC material parameter (Δε, Δn, Kii etc) and LCD parameter (Contrast, Response, Drive Voltage etc) is also discussed.

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This paper presents an outline of printability of offset ink and a solution to trouble shooting in offset printing. Ink transfer from roll to roll is one of the most important features for good printability and printing quality. Both quality control by several factors like solid density or tone value increase and elimination of troubles such as scumming, tinting and ghosting are fundamentally indispensable. In addition, numerous factors exist in printing process and affect both printability and printing quality. In various aspects these factors also affect themselves one another. Effective control of those factors gives stable printability and better printing quality. Thus standardization in printing process is becoming important.

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