A dimming-control lighting apparatus for an incandescent electric lamp with less
accompanying color temperature change, using a dimming power source installed in
TV studios or theater stages, is disclosed. The voltage of the first filament whose
rated voltage is lower than the maximum output voltage of a dimming power source
rapidly rises to the sawtooth voltage of the dimming power source, and after the
first filament reaches a constant color temperature, the output of the second filament
having the same rated voltage as the maximum output voltage of the dimming power
source is delayed to thereby light the second filament. Thyristors and connected
to the first filament and the second filament, respectively, are operated by the
control of control means based on the detection of the ignition phase angle of
the sawtooth wave of the dimming power source to thereby light the first filament
and the second filament (lamps), as mentioned above, so that dimming control having
a smaller color temperature change is performed using the dimming power source.