| 摘要 |
PURPOSE:To control both the frequency temperature characteristics and the oscillation frequency, by cutting away by the laser beam a part of the control electrodes of an inverted triangle and a rectangle which are formed by vapor deposition at the specified parts on both surfaces at the tip of the tuning fork arm of a coupled tuning fork type quartz oscillator that is used to an electronic wristwatch. CONSTITUTION:A coupled tuning fork type quartz oscillator 1 is supported by a supporting lead 2. The resonance frequency of the 1st higher harmonic wave F1 is referred to as fF for the refractive oscillation of the oscillator 1, and the resonance frequency of the basic twist oscillation is fT respectively. Then the ratio between fT and fF is defined as R. The 3rd temperature characteristics is obtained at a room temperature when R is set at a specified value. An R control electrode 8 and an fF control electrode 9 are provided on both surfaces of parts D and E near the tip of the tuning fork arm to control both fF and fT. The node D of F1 exists at the area of about 0.2 from the tip of the tuning fork arm when the arm's length is defined as 1. Thus the electrodes 8 and 9 are formed in a rectangle and a triangle at the regions of 0.1-0.4 and 0-0.2 from the tip of the tuning fork arm respectively. The electrodes 8 and 9 thus formed by vapor deposition are cut away to ensure a control to a desired characteristics. |
