Introduction. Visually-impaired or severely visually impaired persons are primarily guided by their existing vision. Unfavorable lighting can further reduce the already reduced visual potential. The primary goal of this work is the creation of barrier-free lighting and lighting solutions as well as the development of a calculation method for the subjectively perceived contrast. From this, the resulting recommendations and guidelines for planners and for standardization have been derived. Methods. For the examination of the visual performance in different light conditions, a new dedicated experimental setup was developed by which different adaptation lighting densities could be generated. A variety of visual tests were presented by means of a brightness-adjustable monitor and the visual performance was determined as a function of the adaptation luminance as well as glare. In the form of interviews, the subjective feelings of the visually impaired subjects were also surveyed. 98 visually impaired people and 38 normal sighted people participated in the study. Results. The results of the interviews showed that most of the visually impaired persons have individual light requirements. In this group of people the need for light is increased in more than 50 % of the examined persons and in 75 % an increased glare sensitivity is present. Problems with adaptation and uneven lighting are also mentioned. Visually impaired persons show a clear effect in the visual performance at different levels of brightness. In the case of glare, the persons with eye diseases have a strongly reduced contrast threshold and a higher subjective disturbance sensation compared to normal eyesight. In general, glare has a decisive influence on the visual performance of visually impaired people. For the contrast calculation taking into account external and physiological influences, the glare-contrast-sensitivity and the contrast calculation according to Hauck were developed. Conclusions. For general lighting, a predominantly indirect lighting is to be preferred for visually impaired people. For horizontal illuminance in commonly used premises the values from ÖNorm EN 12464-1 are to be used. For a good visual communication attention should be paid to a high cylindrical illuminance. In individually used rooms as well as in visually impaired workplaces the individual brightness requirement should be considered. Glare should generally be kept as low as possible. A UGR value < 13 should be aimed for. For the calculation of the photometric contrast of materials to each other, the application of the Michelson formula is very well applicable. In order to be able to perceive contrasts, physiological aspects and the surrounding conditions must be considered. Here, the new contrast calculation according to Hauck has clear advantages.