A far-infrared radiation multi-stage type heating furnace for steel sheets for hot stamping, the furnace including far-infrared radiation heaters having flexibility that are prevented from deflecting even during heating at temperatures ranging from the Ac.sub.3 transformation temperature to 950 C. The furnace includes: multiple-staged heating units that accommodate steel sheets, each heating unit formed by thermal insulation materials disposed around the periphery; and far-infrared radiation heaters positioned above and below the heating units. A far-infrared radiation heater is received by first metal strips. The first metal strips are disposed so that their strong axis direction approximately corresponds to the direction of gravity and supported by support pieces so as to be expandable and contractible in a longitudinal direction by thermal expansion or thermal contraction. The support pieces are disposed outside the thermal insulation materials in the heating units and a ceiling unit.

A plasma processing apparatus according to an embodiment includes a processing container, a mounting table, a plurality of heaters, and a power supply device. The mounting table is provided in the processing container. The plurality of heaters are provided in the mounting table. The power supply device supplies electric power to the plurality of heaters. The power supply device includes a plurality of transformers and a plurality of zero-cross control type solid state relays (SSRs). The plurality of transformers are configured to step down a voltage from an alternating-current power source. Each of the plurality of transformers includes a primary coil and a secondary coil. The primary coil is connected to the alternating-current power source. Each of the plurality of SSRs is provided between one corresponding heater among the plurality of heaters and the secondary coil of one corresponding transformer among the plurality of transformers.

A plasma processing apparatus according to an embodiment includes a processing container, a mounting table, a plurality of heaters, and a power supply device. The mounting table is provided in the processing container. The plurality of heaters are provided in the mounting table. The power supply device supplies electric power to the plurality of heaters. The power supply device includes a plurality of transformers and a plurality of zero-cross control type solid state relays (SSRs). The plurality of transformers are configured to step down a voltage from an alternating-current power source. Each of the plurality of transformers includes a primary coil and a secondary coil. The primary coil is connected to the alternating-current power source. Each of the plurality of SSRs is provided between one corresponding heater among the plurality of heaters and the secondary coil of one corresponding transformer among the plurality of transformers.

A coated graphite heater. The heater has a configuration comprising a plurality of heating elements having a major portion disposed parallel to an upper surface of the heater so that the major portion is disposed horizontally. The heater configuration provides a heater that exhibits reduced thermal stress and/or reduced CTE mismatch stress particularly compared to designs having heating elements with a major portion oriented perpendicular to the plane of the upper surface of the heater.

A coated graphite heater. The heater has a configuration comprising a plurality of heating elements having a major portion disposed parallel to an upper surface of the heater so that the major portion is disposed horizontally. The heater configuration provides a heater that exhibits reduced thermal stress and/or reduced CTE mismatch stress particularly compared to designs having heating elements with a major portion oriented perpendicular to the plane of the upper surface of the heater.

A metal wiring bonding structure 100 comprises contacts 753 of connection FPC 75 and heater lands 46 of a sheet heater 30 to be bonded by a solder bonding member 766. A connection FPC 75 includes contact opposed lands 754 famed of metal and disposed at positions respectively opposed to the plurality of contacts 753 on a surface of a support layer 751 opposite from a surface on which metal wires 750 are provided, and through holes 755 penetrating the contact opposed lands 754, the support layer 751, and contacts 753. Solder bonding members 756 cover surfaces of contact opposed lands 754 and are filled inside through holes 755 and in a bonding space C.

A metal wiring bonding structure 100 comprises contacts 753 of connection FPC 75 and heater lands 46 of a sheet heater 30 to be bonded by a solder bonding member 766. A connection FPC 75 includes contact opposed lands 754 famed of metal and disposed at positions respectively opposed to the plurality of contacts 753 on a surface of a support layer 751 opposite from a surface on which metal wires 750 are provided, and through holes 755 penetrating the contact opposed lands 754, the support layer 751, and contacts 753. Solder bonding members 756 cover surfaces of contact opposed lands 754 and are filled inside through holes 755 and in a bonding space C.

A system for positioning an optical preform in a furnace is provided that includes an upper muffle and a downfeed handle assembly with a tube defining a first end and a second end, the second end extending into the upper muffle. A handle is disposed within the tube. A second end of the handle extends into the upper muffle and a seal assembly is positioned around both the tube and the handle. The first end of the handle extends through the seal assembly and a drive assembly is coupled with the downfeed handle.

A system for positioning an optical preform in a furnace is provided that includes an upper muffle and a downfeed handle assembly with a tube defining a first end and a second end, the second end extending into the upper muffle. A handle is disposed within the tube. A second end of the handle extends into the upper muffle and a seal assembly is positioned around both the tube and the handle. The first end of the handle extends through the seal assembly and a drive assembly is coupled with the downfeed handle.

A gas phase type heating method includes loading an object into a vapor heating furnace or a heating furnace via a loading/unloading portion, cooling vapor of a heat transfer liquid by a cooler provided above the loading/unloading portion in the vapor heating furnace, and causing a gas to go in and out, making a pressure in a continuous furnace uniform, and heating the loaded object, by a connection portion that is provided above the cooler and has a pressure loss smaller than a pressure loss of the loading/unloading portion.