| 摘要 |
PURPOSE:To inexpensively manufacture the titled card with a function having a very strong illegal prevention by arranging at least two kinds of magnetic materials in an optional order with different coercive force and recording a data specific to the card depending on the arranged order of the magnetic materials and/or its magnetizing direction. CONSTITUTION:At least two kinds of magnetic materials having a different coercive force are arranged in an optional order and the data specific to the card is recorded depending on the arranged order of magnetic materials and/or its magnetizing direction. The magnetic material regions 16H, 16L made of at least two kinds of magnetic materials whose coercive force differs are magnetized at first in one direction, and a reverse magnetic field stronger than the minimum coercive force is applied to invert the direction of magnetization sequentially from the magnetic material with smaller coercive force. The reproduction signal is compared before and after the inversion to detect the position of the magnetic material having magnetization inversion and the distribution of coercive force is detected finally to discriminate and confirm the correct magnetic card. Thus, the recording structure of the specific data is hardly known by the result of observation or reproduced waveform by a magnet viewer, the preventing function against forgery or modification is high and the entire system is formed inexpensively.
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