Differential Position Sensor with Amorphous Wires in a Silicon Membrane

Sensors used in the medical field require biological compatibility and low electricity. This paper proposes a new differential position sensor with amorphous wires in a silicon membrane (A-S sensor). A sensor was manufactured and its characteristics were evaluated. The results may be summarized as follows:1. The ac permeability of the amorphous wires was in the range from 830 to 21,000 for frequencies from 1 kHz to 100 kHz. It is recognized that the amorphous wires were made of high-permeability material.2. To satisfy the conditions of reduced electricity and increased sensitivity, the frequency chosen must be in the range from 46 kHz to 74 kHz.3. The detective sensitivity of the A-S sensor was shown by using the following appr oximate expression:Vout=26.4x [V]The A-S sensor has a potential application in monitoring a patient‘s heart beat to prevent sudden death.