Assessment of optimal ambient lighting: Comparision of two methods

Abstract Optimal lighting is an essential part of visual rehabilitation. Generally, lighting levels are assessed depending on the amount of light that is required to fulfil a task. However, it is equally important to assess tasks that rely on ambient lighting. This study compares two different methods to assess optimal ambient lighting levels for people with visual impairment. Method Two different methods were used. During the first method, the 3D Lightlab, subjects were seated on the side of a room and asked to describe which objects they detected and which objects they recognised in the room during increasing illumination levels. In the second method, subjects were asked the same question, but the room and the objects were projected on a screen with a beamer. Illumination levels were controlled using ND-filters. Results Illumination levels for optimal lighting are comparable for both Lightlabs. However, patients have a higher confidence level in the outcome of a 3D Lightlab. Significance Although the 3D Lightlab is generally preferred by people with visual impairment, the 2D Lightlab is suitable for implementation in visual rehabilitation for clients who need to know their illumination levels for optimal lighting.