Overview: Blue light irradiation therapy is a simple, efficacious and fast-acting method for treating neonatal jaundice. Jaundice is a high bilirubin content in the baby’s body, and bilirubin absorbs light, and under the action of light and oxygen, fat-soluble bilirubin is oxidized into a water-soluble product, which can be discharged from the bile or urine, thus lowering the concentration of serum unconjugated bilirubin. It is generally believed that the wavelength of 440-470nm blue light has the strongest effect on bilirubin, which can oxidize bilirubin into a non-toxic water-soluble product, so that jaundice deposited in the skin can be discharged from the body as soon as possible through feces and urine, so it is commonly used in this way to treat jaundice in babies. Physiological jaundice: no need for blue light irradiation, can subside on its own Pathological jaundice: intermittent blue light irradiation is mostly used in the clinic, which is stopped after 4-8 hours of irradiation, and at the same time, bilirubin levels are monitored until bilirubin decreases to within the normal range, and then a decision is made whether or not to discontinue the treatment based on the hourly bilirubin curve of the neonate. During phototherapy the child is exposed to the skin as much as possible so that there is a large contact area with the blue light to improve the efficacy of the treatment. The eyes and genitals should be covered with a black cloth during phototherapy to prevent damage to the retina and reproductive function. For children with congenital bilirubin metabolism anomalies, their bilirubin levels are prone to recurrence, and the irradiation time should be relatively longer.