Methods and devices related to the treatment of diseases using phototherapy are described. Some embodiments provide an organic light-emitting diode device, such as a light-emitting device for phototherapy, comprising Ring system 1, Ring system 2, Ring system 3, or Ring system 4. Methods of treating disease with phototherapy are also described.敘述關於使用光療以治療疾病的方法和裝置。一些實施例提供有機發光二極體裝置,例如光療用的發光裝置,其包含環系統1、環系統2、環系統3、或環系統4。亦敘述以光療治療疾病的方法。