目視によるモニタの階調再現特性および白色点の色度に対するキャリブレーション手法の検討 A Visual Calibration Method for Calibrating the Tone Reproduction Curve and the Chromaticity of White Point of a Monitor
These days, soft proof, which checks color images of printed matter on a monitor, is widely used in the field of graphic arts. In order to provide high quality soft proofing system, it is necessary to calibrate the tone reproduction curve and the chromaticity of white point of a monitor to desire characteristics and to make an ICC display profile. In such a background, we developed a method to calibrate them with low cost and high quality by visual calibration. This paper reports the principle and calibration accuracy of our method. In general, it is well known to adjust brightness of a continuous tone image with that of a binary image on a monitor for calibrating tone reproduction curve of the monitor. On the other hand, our method adjusts brightness and hue of three continuous tone images to those of binary images. As a result, our method can calibrate nonlinear tone curve of LCD accurately. In addition, our method can be applied to many viewing illumination conditions, because our method adjusts a color of white point of the monitor to that of target paper under a viewing illumination. Three experiments using three different LCDs were done to test the calibration accuracy of our method. The results of the experiment show the monitors calibrated by our method have enough accuracy for soft proof.
日本印刷学会誌 45(2), 89-100, 2008-04-30
The Japanese Society of Printing Science and Technology