| 摘要 |
PURPOSE: To measure acceleration in a direction parallel to a substrate and perpendicular to a beam. CONSTITUTION: A weight 61 and beam 62 are displaced by acceleration Y which is parallel to a silicon substrate 50 and perpendicular to the beam 62 and another accelerationαZ which is perpendicular to the substrate 50. When piezo- resistors 64-1 and 64-2 are respectively strained by e1 and e2 , e1 -e2 =9.6mldY/ Ea<2> b, and e1 +e2 =12mlαZ/Eab<2> are established. Since the resistance of the piezo-resistor 64-1 varies proportionally to the displacement of the resistor 64-1 by the strain e1 , the variation of the resistance is measured as the output voltage of a detector. Similarly, the variation of the resistance of the piezo- resistor 64-2 is measured as the output voltage of the detector. A computing element calculates the accelerationαY by taking the difference between the outputs of the detector and multiplying the difference by a constant. The computing element, in addition, calculates the accelerationαZ by taking the sum of the outputs of the detector and multiplying the sum by a constant.
|
