A fluorescent lamp controlling circuit reduces andor prevents a fluorescent lamp from suddenly flickering when a power switch is turned on andor off. In the start-up method, the phases of gate signals of third and fourth switching devices are gradually shifted relative to the phases of gate signals of first and second switching devices. The anisotropic scattering member has a scattering center and scatters light traveling along a scattering axis direction which is a direction having a predetermined angle range centered around the scattering center. The protector member is movable between a reception position in which the protector member is received in the receiving section, and a projection position in which the protector member projects to an outside of the main body through the opening. A first of the valve outlets provides exhaust gas to the EGR system for recirculation to the engine air inlet passage, a second of the valve outlets provides exhaust gas to the exhaust gas bypass passage and a third of the outlets provides exhaust gas to the impeller.