Patent
Magneto-optical recorder with small-sized, low-powered electromagnetic coil
Takeshi Nakao,Yutaka Akiba +1 more
TLDR
In this article, a magneto-optical recorder is disclosed in which an external magnetic field required for recording and erasing can be produced by a small-sized electromagnetic coil having a small magneto motive force.Abstract:
A magneto-optical recorder is disclosed in which an external magnetic field required for recording and erasing can be produced by a small-sized electromagnetic coil having a small magneto-motive force. The electromagnetic coil is made up of a magnetic core and a coil winding, and the outer peripheral portion of the coil winding other than that peripheral portion thereof which confronts a recording medium, is covered by a core material. A magnetic field emanating from the electromagnetic coil spreads in a narrow space, and can be applied to the recording medium with large intensity even when the electromagnetic coil has a small magneto-motive force. In the recorder, a magnetic body is disposed such that the electromagnetic coil and the magnetic body face each other, to concentrate the magnetic field generated by the electromagnetic coil, to the vicinity of that portion of the recording medium which is irradiated with a light spot. The length of the electromagnetic coil is made equal to or greater than the length of the recording area of the recording medium, to apply a substantially uniform magnetic field to the whole recording area without moving the electromagnetic coil.read more
Citations
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References
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Patent
Magnetic imaging apparatus
TL;DR: In this paper, the cooperative action of two opposite-polarity, concentric magnetic poles is used to create a somewhat doughnut-shaped defined magnetized zone, which is characterized by multi-directionally oriented magnetic vectors distributed generally with spherical geometry.
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TL;DR: In this article, the authors presented a method to obtain a writing magnetic field and an erasing magnetic field of sufficient intensity by providing an electromagnet opposite to a condenser lens and a magnetic body, which focuses a magnetic field generated by the electromagnetic field on a beam-irradiation point on a recording medium, at the condenser-lens side.
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TL;DR: In this article, a magnetic head has three pole pieces that form a magnetic circuit and are arranged in a common plane so that the two outside poles are each spaced from the central pole piece to form a transducing gap between each of the outside pole pieces and the central poles, and a first and a second coil, each having the same magnetic sense, is wound on the magnetic structure between an outside and the center pole piece.
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TL;DR: In this paper, a magnetic flux phi flows to a magnetic path consisting of a magnetic pole 5 and a yoke 7 when an exciting coil 6 is conducted electricity, and it is possible to impress a magnetic field having the direction vertical to the medium 1 which is opposite to the tip of the pole 5.
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