| 摘要 |
PROBLEM TO BE SOLVED: To reduce the reflection of a surface acoustic wave transferred on a substrate for increase in the traveling speed of a movable body and energy efficiency by forming two surface acoustic wave exciting electrodes disposed separately from each other on a piezoelectric substrate out of one-way electrodes. SOLUTION: Two one-way electrodes 2, 3 are mounted on a piezoelectric substrate 1 and connected to power sources 4-7. The one way electrode 2 consists of two interdigital electrodes 2A, 2B, which are disposed separately from each other by one-fourth wave length, and the one-way electrode 3 is formed so that the pattern of the electrode 2 may be reversed, and consists of two interdigital electrodes 3A, 3B. A solid movable body 10 is disposed between the one-way electrodes 2 and 3. The phase difference of a surface acoustic wave generated by the electrodes 2A, 2B becomes π and weakens each other on the side where the movable body 10 does not exist, and the phase difference becomes zero and strengthens each other on the side where the movable body 10 exists. Voltage is regulated, and respective amplitudes of waves on the side where the movable body 10 does not exist are equalized to cancel the waves each other, thereby suppressing energy loss. |
