Publications by authors named "Michinobu Matsuyama"

This study was conducted to measure the recognition time of the test pattern and to investigate the effects of the maximum luminance in a medical-grade liquid-crystal display (LCD) on the recognition time. Landolt rings as signals of the test pattern were used with four random orientations, one on each of the eight gray-scale steps. Ten observers input the orientation of the gap on the Landolt rings using cursor keys on the keyboard.

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Liquid-crystal displays (LCDs) with different types of surface treatment have been developed for decreasing the effect of ambient lighting on a displayed image. The effect of ambient lighting on LCDs with different surface treatments, namely, glare (G)-type, anti-glare (AG)-type, and anti-reflection (AR)-coating LCDs, was evaluated quantitatively in this study for appropriate selection. The effect of ambient lighting on diffuse reflection and specular reflection was investigated.

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Although variation of chromaticity in medical liquid-crystal displays (LCDs) has created interest in the quality assurance and quality control of display devices for medical use, it is unknown how chromaticity varies with the viewing angle. Our aims in this study were to investigate the variations of chromaticity in grayscale images displayed on medical LCDs depending on viewing angles, and to examine color discrimination at different viewing angles. Variations in chromaticity, Δu'v', between 0° and each viewing angle (-60° to +60°) were investigated.

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Purpose: The color characteristics of medical liquid-crystal displays (LCDs) have become one of the main interests in quality assurance and quality control of medical display devices. It is necessary to evaluate variations of the color characteristics in medical LCDs in order to provide consistent color characteristics for image reading. In this study, we characterize the color characteristics in grayscale images displayed on medical LCDs.

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