A method of removing an oxide layer from an article. In some examples, the system detects an increase in temperature at a treatment device in contact with the skin of a subject, determines that the increase in temperature is related to a treatment event, and performs an action based on the determination. Emitting lights of the light emitting elements on a lower side transmit the light emitting elements on an upper side, and emitting light of the light emitting element positioned uppermost directly irradiates a surface to be irradiated. The thin film coil is covered by the insulating layer whose surface is flattened. Thus, the opening ratio of the liquid crystal panel increases, and the integration density thereof can be reduced, thereby simplifying the production process of the liquid crystal panel and reducing the manufacturing costs for the liquid crystal panel.