| 摘要 |
<p>PURPOSE:To identify an electric signal by a frequency level by providing an oscillator, which is directed to the peripheral part of the tip of a penpoint and oscillates high frequency oscillating waves having a natural frequency, in the peripheral part surrounding the penpoint of a holder body and connecting the oscillator to an oscillating circuit. CONSTITUTION:A holder body 15 is formed into a narrow and long cylinder, and a penpoint 16 such as a felt pen, an oscillating circuit 17, and a cell 18 like a dry cell are stored in the holder body 15. Detecting circuits 33 are attached to both ends of a high polymer piezoelectric sheet 1 to calculate potentials VL and VR generated in the left and the right. In this case, the + terminal of an operational amplifier (O.P) is grounded similarly to a metallic film 4. When a distortion occurrence point of a resistance value 3 is defined as a variable (x), coordinates (x) of the distortion occurrence point at a time t = t0 are obtained in accordance with VR(to) and VL(to), and the difference between respective signals of counter electrodes 5x and 5x is divided by the sum value to obtain coordinates (x) as displacement from the center point of a resistance film 3, and a writing tool 14 is displayed as coordinates of the writing position, and a coordinate signal having the same motion as the form of a character on an electronic blackboard 7 is taken out simultaneously. Thus, simultaneous display of many points and color display are accurately and easily performed.</p> |
