Philips 40PFL8664H User Manual page 31

1.4.2 Ambilight
Ambilight is the lighting technology that emanates
from the back of the television onto the wall. This
innovative technology automatically adjusts the colour
and brightness of the light to match the TV picture.
This creates an unprecedented improvement in viewing
experience. The light also reduces eyestrain thus providing
a more relaxing viewing experience.
Read more on Ambilight in Use your TV.