| 摘要 |
PURPOSE:To apply a field across electrodes to cause mass transfer due to migration after adjusting the frequency of the crystal piece and to achieve a fine adjustment, which is provided with plural electrodes consisting of thin films consisting of Ag or the like, within a specified variation and sealing it hermetically in vacuum. CONSTITUTION:Cr, Ni, Ti, or the like is stuck to the surface of a tuning fork crystal piece 1 cnsisting of a resonance part 1a and a base part 1b, and Ag is stuck to it to form an electrode 3. An insulating film consisting of a phenolic resin or the like is formed in a dotted part 4. The crystal piece 1 is fayed to an airtight terminal 5, and a laser beam 6 or the like is used to remove the additional mass of the tip of the resonance part, and the crystal piece 1 is sealed hermetically in vacuum to adjust the frequency within + or -50ppm. Next a DC voltage 8 is applied across stems 5b of the terminal 5 to generate a field in the insulating film of the dotted part 4, thereby causing mass transfer due to migration of Ag. As the result, the frequency is adjusted finely to adjust the variation of the frequency. |
