Luminance contrast analyses for low vision in a senior living facility: A proposal for an HDR image-based analysis tool

This study proposes the use of digital photography as a visual assessment tool to incorporate the needs of the aging eye to the design process. The research utilizes digital photographs to collect luminance and luminance contrast data, and employs visual field masks to represent and analyze human's visual field. Digital image blurring filters are developed to examine contrast perception problems related to visual acuity (specifically, recognition acuity) loss. Employing an experimental design for tool testing and involving a case study of a senior living facility for empirical data collection, the proposed research aims to verify using a digital image-based analysis tool to represent the visual acuity levels of the aging eye, and explore luminance distribution and luminance contrast ratios that cause mobility problems and affect the safe orientation of people with low visual acuity. The results of the case study demonstrated the viability of the proposed tool, highlighting reduced luminance contrast on the egress staircase for lower visual acuity conditions. The outcomes include lighting design caveats with respect to preventing injuries and falls, and facilitating accessibility and comfort in senior living environments. Future research can benefit from the proposed methodology to study both qualitative and quantitative aspects of the luminous environment in different indoor and outdoor contexts. The proposed method and analysis of luminance contrast values will help revisit the viability of the existing lighting guidelines and develop perceptual lighting metrics that take into account the lighting-related needs and preferences of senior populations.