| 摘要 |
PURPOSE:To enable one vibrator to obtain frequency-temperature characteristics equivalent to those of two vibrators combined, by using a vibrator which has the boundary of an electrical twin crystal in parallel to a plane obtained by turning the Z plane on the X axis by 1 to 10 deg.. CONSTITUTION:A sample is selected which has boundary M of an electrical twin crystal nearly in parallel to the Y-axial direction of X-cut sample A, and then cut so that boundary M of the twin crystal will be at the center of blank N; its size is determined by polishing and an angular correction of less than 10 deg. is made around the X axis. Further, the sample is finished into a tuning fork with right and left crystals confirmed and divided by boundary M with polarities made equal at the flank before electrodes are fitted. In this case, the electric twin crystal is opposite in polarity and cut angles are ''+x deg.'' and ''-x deg.'' respectively; and this results in that two vibrators with zero-temperature coefficient temperatures Tpa and Tpb are connected in parallel and the frequency-temperature variation is shown by curve (c), which is improved one. |
