Most medical images are presented in two dimensions by intensity on a film or electronic media such as video. The display process of transforming the recorded image into a viewable image on these media fails to transmit some or much of the useful information in the recorded image. We propose research to improve this information transfer in the 2D display process. To achieve this improvement, we will accomplish the following objectives: (1) Develop and prove a methodology for standardizing the display system so that, independent of the display device, changes in display driving intensity produce a predictable perceptual result, and one that optimizes the effect of contrast enhancement methods designed to maximally transmit diagnostic information. (2) Determine the display scale sensitivity that is optimal for presentation of medical images or classes of medical images, as a function of target sharpness and signal to noise ratio. (3) Study the effect of image structure on the contrast required for feature discrimination in medical images. This study will not only produce results necessary for achieving the other objectives, but it will also develop further understanding of the process of perception of medical images that can lead to other improvements in imaging, processing, and display.