| 摘要 |
PURPOSE:To read co-ordinates with high accuracy extending over a wide range, by repeatedly generating AC magnetic fields whose phase is different, at every area so that they become same, and providing an AC magnetic field generation part for generating an AC magnetic field which is capable of discriminating the area by frequency, level, phase, timing, etc. CONSTITUTION:An AC magnetic field generation part 1 has plural areas A, B- for generating AC magnetic fields having each different phase phi1-phi4, and also generates magnetic fields B1, B2- showing the areas A, B-. A plate 2 is used for placing a form on which an input item, etc. have been printed in advance, and indicating by a magnetic field detector 3, or placing a blank sheet of paper and entering a character, etc. by the magnetic field detector 3 constituting a writing tool. The magnetic detector 3 has coils of a phase detecting part and an area detecting part, and a signal corresponding to phase is applied to a processing device 6 by detecting the phase of a detecting signal of the magnetic field detector 3 by reference phase in a phase detector 4. Also, an area detector 5 detects an area and provides it to the processing device 6. The processing device 6 derives co-ordinates by the detecting signal and outputs them. |
