| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a two-stage force sensor keyboard having at least one key and a thin film switching circuit positioned below the key. <P>SOLUTION: A thin film switching circuit comprises: a first junction; a second junction; a first separation layer to separate the first junction and the second junction; a third junction; a fourth junction; and a second separation layer to separate the third junction and the fourth junction. The second separation layer is thicker than the first separation layer. When a key is pressed due to a primary pressure, the first junction gets contacted with the second junction generating a first signal. And when the key is pressed due to a secondary pressure, the first junction gets contacted with the second junction as well as the third junction gets contacted the fourth junction generating a second signal. The larger a proportional value of the thickness of the second separation layer and the thickness of the first separation layer becomes, the easier it is for a user to identify a difference between the primary pressure and the secondary pressure. <P>COPYRIGHT: (C)2012,JPO&INPIT |
