| 摘要 |
PURPOSE:To set the position with high accuracy, by producing many linear electrodes connected to common electrodes and then cutting off some linear electrodes from the common electrode in response to the position to be adjusted. CONSTITUTION:An inter-digital transducer 13 produces two surface acoustic waves which propagate in directions opposite to each other to diffract optical bit signals a1 and b1 showing two signals. In order to produce the transducer 13, many linear electrodes 31 which are parallel to each other and two common electrodes 32 are formed by a photolithographic process for example so that the electrodes 31 are connected to the electodes 32 alternately. Then an electrode 31a is cut off from the electrode 32 with irradiation of laser light, etc. to correct the distance in case distances l1a and l1b are different from the electrode 31 of the end part through points of diffraction of the signals a1 and b1 respectively. |
