The invention relates to a liquid detecting apparatus that drives a liquid detecting unit that outputs two detection signals having phases opposite to each other in accordance with the amount of liquid. The deflecting section deflects the electron beam and corrects distortion of an image of the electron beam on the wafer. The pulse of light permits the testing of dynamic and static characteristics of the SLM, while the use of optical computational units in the computation of the correlation image greatly reduces computational requirements and testing time. First and second transmission lines are coupled to respective folded dipole portions. The power controller controls the voltage to be supplied to the electronic devices with a low voltage, a reference voltage higher than the low voltage, and a high voltage higher than the reference voltage in accordance with an idle stop state, a constant velocity traveling state, an acceleration state, and a deceleration state of the vehicle. In particular it involves the use of non-reactive hot melt adhesives and flexible polyolefin films.