A light stick is formed from an elongated, light-transmitting member having a plurality of grooves formed in its exterior surface and an aperture at one end for receiving a light source, such as a light-emitting diode (LED). The light from the LED is directed into the interior of the elongated member....http://www.google.ca/patents/US6857771?utm_source=gb-gplus-sharePatent US6857771 - Light stick with LED light source
