Patent attributes
A planar heater 1 in which a power supply terminal unit 108 which supplies an electric power is arranged on a central portion on a lower surface of a silica glass plate-like member 102. The power supply terminal unit includes small-diameter silica glass tubes 105a and 106a, which contain a connection line which supplies an electric power to a carbon heat generator and a large-diameter silica glass tube 2 which contains the small-diameter silica glass tubes 105a and 106a. A flange portion 2a is formed on a lower end of the large-diameter silica glass tube 2, and a bent portion 2b having different diameters is formed between an upper end of the large-diameter silica glass and the flange portion 2a, and the first heat shielding plates 19, 20 and 21 configured by metal plates or opaque silica glass plates are contained in the large-diameter silica glass tube below the bent portion.
