Patent ID: 8564201

Claim:
A lamp circuit comprising: a heating circuit configured to heat an auxiliary amalgam-based material in a tube containing the auxiliary amalgam-based material and a main amalgam-based material; and a driver circuit configured to during a start-up period, control the heating circuit to heat the auxiliary amalgam-based material to an elevated temperature at which the auxiliary amalgam-based material releases mercury, and after the start-up period, control the heating circuit to lower the temperature of the auxiliary amalgam-based material to a temperature at which the auxiliary amalgam-based material absorbs mercury, while the main amalgam-based material is heated to a lamp operating temperature at which the main amalgam-based material releases mercury; and wherein the driver circuit is further configured to control the heating circuit to heat the auxiliary amalgam-based material to an elevated temperature at which the auxiliary amalgam-based material releases mercury by during an initial rapid heating portion of the start-up period, driving the heating circuit to a temperature that is above the temperature at which the auxiliary amalgam-based material releases mercury, and after the rapid heating period, driving the heating circuit to a reduced temperature to maintain the auxiliary amalgam-based material at a temperature that is at least as high as the elevated temperature.