Projection and reflection: where is the difference?
A comparison of optics
Projection: light control via lenses
Lens systems feature high precision and efficiency. High uniformity in terms of brightness and colour constancy is generated within the light beam. Imperfections or spill light losses are avoided because all light rays are guided through the lens system. This means that operators benefit from high efficiency (lx/W). Even very narrow light beams for striking accents can be implemented.
Reflection: light control via reflectors
With light control via reflectors, only the light rays emitted to the side are controlled. Therefore very narrow light beams are not possible. Furthermore, high spill light losses (red lines) or not clean beams (e.g. halos) occur. Unfocused and sometimes coloured edges to the light beams may also occur as well as a non-uniform distribution of illumination in the centre.