| 摘要 |
<PICT:1024330/C1/1> A method of making a ferro-electric crystal, e.g. of BaTiO3 having two orthogonally oriented domains, comprises heating a wafer of a multi-domain ferro-electric to a temperature near its Curie point and cooling it whilst subjecting it to an electric field, e.g. of about 1 kV/cm. parallel to the plane of the wafer, and then subjecting a part of the wafer to a field perpendicular to the plane of the wafer in order to obtain a second domain polarized at right angles to the first. Fig. 4 shows a rectangular wafer of barium titanate having two such domains 5, 6 separated by a partition 7 which forms an angle of about 45 degrees with the face of the wafer. The position of the partition may be varied between limits 7a, 7b by means of a voltage applied across electrodes 8, 9. |
