Patent ID: 8315510

Claim:
A light emitting type heat treatment apparatus, comprising: two types of filament lamps including two or more relatively low rated power density filament lamps and two or more relatively high rated power density filament lamps whose rated power density is higher than that of the two or more relatively low rated power density filament lamps, in which a heat treatment includes a temperature raising heat process for raising a temperature of a work piece to a predetermined heat treatment temperature by light emitted from the filament lamps and a constant temperature heating process succeeding the temperature raising heating process for maintaining the predetermined heat treatment temperature of the work piece; and a control unit operative to control a light-ON state and a light-OFF state of the two types of filament lamps so that, for the temperature raising heat process, at least the filament lamps with relatively high rated power density are in the light-ON state and, for the constant temperature heating process, the filament lamps with relatively low rated power density are in the light-ON state and the filament lamp with relatively high rated power density are in the light-OFF state.