| 摘要 |
A contactless SAW-based torque and temperature sensor comprising a first 2 and a second 3 SAW resonator provided on a substrate made of Y+34{ cut of quartz. The first SAW resonator 2 has its principle axis inclined at +45{ to the X-axis of the substrate, which, in use, is either aligned with the longitudinal axis of the device whose torque is to be measured or is perpendicular thereto, and the second SAW 3 has its principle axis inclined at -45{ to the X-axis of the substrate. A third SAW 4 has its principle axis inclined at an angle of 30 degrees to the X-axis of the substrate. Each said SAW resonator 2, 3, 4 is formed by laying a film of aluminium on the substrate having a thickness (h) and the SAW resonators have an average operating wavelength X where the ratio h/X is in the range 0.021 to 0.032. The resonators may operate in the frequency range 428 - 437 MHz; preferably the aluminium has a thickness in the range 160 - 240 nm. |
