White light-emitting diodes (LEDs ... eventually becoming a uniform natural white (a colour temperature of 6,000 K) at drive currents of 20 mA and above.

The emergence of convenient sources of broadband light spanning the visible and near-infrared is proving increasingly useful for applications involving spectroscopy, imaging and metrology ...

Lots of different sources produce light. Earth's main source of natural light is the Sun. At night, moonlight is created by the moon reflecting the Sun's light. This allows us to see at night ...