There is provided a method of easily forming thin film transistors having the same characteristics in fabricating a differential circuit or a current mirror circuit utilizing two thin film transistors made of a polycrystalline silicon semiconductor. By applying the organic light emitting element using this metal complex, an inexpensive light emitting device which is bright but consumes little power can be provided as well as an electric appliance using the light emitting device. The main tube is configured to transfer torque between the first and second links. In the first mode, a peak voltage and a baseline voltage are sequentially directed to the actuator. One end of the horizontal body of the reaction chamber is fluidly attached to the combustion chamber, while the other end of the horizontal body of the reaction chamber is fluidly attached to a lower end of the upright plenum of the reaction chamber. The covering elements extend over the entire width of the floor marking and taper on both sides at one of their ends so that a recess bounded by an acute-angled isosceles triangle is formed there.