Purpose: Recently, monitors with maximum luminance exceeding 2000 cd/m2 (high-luminance monitor) have been used for diagnostic mammography. In this study, we examined the visibility of high-luminance monitors by converting luminance meter measurements into the just noticeable difference (JND) Index. The ambient light was also examined at the same time.
Method: The high-luminance monitor is a 21.3-inch IPS monochrome monitor with a maximum luminance of 3000 cd/m2. Experiments were conducted with a minimum luminance of 0.6 cd/m2 and a maximum luminance of 500, 850, and 1200 cd/m2. The luminance ratio was set to 1 : 2000 and the maximum luminance was changed to 500, 1000, and 2000 cd/m2. The ambient light was varied to 8.7, 36.1, 61.3, and 129.6 lx. The Japan Radiological Society recommended luminance values for each stage of phantom and Grayscale Standard Display Function curves were measured.
Result: The JND increased as the maximum luminance was increased for both the case with the same minimum luminance and the case with the same luminance ratio, and visibility was improved.
Conclusion: In both the case of the same minimum luminance and the case of the same luminance ratio, the JND was found to increase as the maximum luminance was increased. The results suggest that high-luminance monitors may improve visibility and allow for higher ambient light settings. Furthermore, the degree of eye fatigue needs to be verified.
Keywords: ambient light; high-luminance monitors; mammography; softcopy interpretation.