Abstract: The present invention, by improving the silicon surface/bulk micromachining technology using two steps of silicon etch mask patterning and four steps of silicon etching, fabricates a structure which has vertically offset electrodes and consequently fabricates an electrostatic vertical and torsional actuator using one single-crystalline silicon wafer. According to the method of the present invention, the problems of the prior art that used a number of silicon wafers and single/double SOI wafers, or combining of these wafers with additional deposited poly-crystalline silicon films, may be resolved.

Abstract: A vehicle detector comprising a loop sensor, phase lock loop (PLL), frequency change detector, and a micro-processor including a logic circuit. Output of the PLL and the frequency change detector is inputted to the logic circuit, and the logic circuit performs logical OR operation of the output of the PLL and the output of the frequency change detector. The output of the logic circuit is used as a vehicle detection signal. The vehicle detector can detect vehicles at a low speed as well as vehicle at high speed accurately.