Patent ID: 7005808
Filing Date: 2006-02-28
Classification: H05B,Y10S

Abstract:
1. A discharge lamp illumination circuit comprising: a DC-AC conversion circuit which effects AC conversion and boosting upon receipt of a DC input; and a starter circuit for supplying a start-up signal to a discharge lamp, the discharge lamp illumination circuit being used for illumination control using control means for controlling a power output from the DC-AC conversion circuit, wherein the DC-AC conversion circuit comprises: wherein the operating frequency of the switching elements is controlled so that a resonance voltage generated at a primary side of the AC conversion transformer is boosted to supply electric power to the discharge lamp from a secondary side of the AC conversion transformer; and wherein when a resonance frequency of the discharge lamp during an extinction period is denoted as fi and a resonance frequency of the discharge lamp during an illumination period is denoted as f