Reflectors And Light Pollution
Reflector Types
Light from a luminaire is controlled by its reflector and the position of the lamp in relation to the reflector.
Below shows the various types of reflectors and the shapes of light output possible.
Asymmetric | Symmetric | Adjustable | Flood | Spot |
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| This reflector makes it possible to direct light towards a preferred area | This reflector gives an even distribution of light for general flood lighting | This reflector permits the light to be adjusted to achieve the desired effect | This reflector makes it possible to illuminate a large area | This reflector enables concentrated light to highlight details without any light overspill |
Light Pollution
External lighting that is badly selected and installed can result in light being directed into the sky. This wastes energy and also ‘pollutes’ the view of the sky.
If lighting is misdirected it can also cause discomfort and visual impairment - possibly resulting in accidents.
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| This luminaire gives upwards light loss | The side of the building is lit and some of the light is lost upwards | The light is aimed downwards but the angle of the luminaire is causing upward light loss |
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| Correct illumination achieved with reflecting louvres | Wherever possible the light should be directed downwards to minimise light pollution | The use of asymmetrical reflectors avoids excessive angling of the luminaire |