To enable the high luminous flux and the brilliance of the metal halide lamps to be fully utilised in any given situation, several luminaires offer two glass diffuser options, each with different properties. The completely frosted diffuser produces an optical increase of the lamp surface while the beam softly fades at the edges. Conversely, the focal diffuser increases illuminance and brilliance in the centre of the beam so that jewellery, glass, porcelain and all other gloss surfaces can be strikingly displayed. The carefully designed anti-glare protection using Darklight technology ensures optimum visual comfort.