Light Emitting Diodes (LEDs) are regarded as the light source of the future. This is because of their outstanding characteristics: LEDs are compact, dimmable, very energy-efficient and, with a life of 50,000 hours, practically never need to be replaced. Made of semiconductor material, LEDs emit light when an electric current is passed through them – in the case of series configurations by a low-voltage driver up to 24 V. Formerly available only as neutral white light sources (colour temperature ≥ 4,000 Kelvin), white LEDs today can deliver a warmer light (3,000 Kelvin).
LEDs are also an alternative for the direct replacement of incandescent lamps. To provide a suitable light source, white LEDs are grouped in a screw base lamp with integrated operating gear. These lamps are mainly intended for decorative accent lighting. Few models at present are a suitable replacement for lamps used to provide general room lighting.
Some LED manufacturers have been involved in the semiconductor market for a long time but have only recently turned to lighting. The LED market is characterised by international competition and large product volumes from Asia. Because LEDs do not fail but lose luminosity through degradation, quality deficiencies are not immediately identifiable. In the case of LEDs, it is therefore particularly important to pay attention to good quality.