These units consist of white or blue lamps which emit light of wavelength 400-500nm. Light of these wavelength oxidizes un conjugated bilirubin into harmless derivatives and so is very important in the treatment of jaundice in neonates. Infant receiving phototherapy have to be nursed naked,which can cause problems of temperature control. There is also increased insensible fluid loss and a theoretical risk of eye damage,so eye shields are placed on the infant.