Phototherapy (Biliblanket) A biliblanket is a portable phototherapy device for the treatment of neonatal jaundice (hyperbilirubinemia). This is a common condition in infants, referring to an increase in the amount of bilirubin in the blood. With the development of flexible fluorescent panels, it was now possible to wrap the infant in the panel during treatment, without eye protection, and still allow the parent to hold the child during part of all of the therapy. .