Alps Electric Co., Ltd.

Hiroshi Yamagami

Masahiro Iizuka

Kinya Aoyagi

Kazuhiro Kaneko

Masao Aoki

Mitsuru Kano

Hiroyuki Hebiguchi

Yoshihiko Ishitaka

Tokuo Nakamura

Seiichi Abiko

Masahiko Yamaguchi

Takashi Saito

Satoshi Maki

Kiyomi Sugawara

Junichi Niijima

Kazuichi Endo

Koji Suzuki

Kazue Masuda

A magnetic head includes a pair of magnetic core halves provided with at least metal magnetic films are combined together so that the metal magnetic thin films of one of the pair of magnetic core halves are abutted on the thin films of the other. A winding slot is provided in the abutting portions between the pair of magnetic core halves to form a front gap and back gap on both sides of the winding slot. The pair of magnetic core halves are bonded together with first bonding glass adjacent to the back gap, and second bonding glass adjacent to the front gap, which as a thermal expansion coefficient higher than that of the first bonding glass.

Multilayer film core magnetic head with bonding glasses of differing thermal expansion coefficients

The ZnO amount contained in the ferrite is lowered more than those of conventional ones to increase the mean coefficient of thermal expansion of the ferrite. Thus, a difference between the mean coefficient of thermal expansion of the ferrite and the mean coefficient of thermal expansion of the soft magnetic material is reduced. Further, the Fe.sub.2 O.sub.3 amount contained in the ferrite is suitably controlled to reduce the absolute value of the magnetocrystalline anisotropic energy K1 and the absolute value of the saturation magnetostriction .lambda.S. Thus, the absolute value of the apparent magnetic anisotropic energy is lowered, and the magnetic anisotropy is weakened. The magnetic permeability and the head output can be elevated in a high frequency region by lowering the magnetic anisotropy.

Magnetic head

The absolute values of the apparent magnetocrystalline anisotropic energy K1 is made large to increase the absolute value of the crystal magnetic anisotropy energy by adjusting the content of Fe.sub.2 O.sub.3 in the single crystal ferrite to 50 to 52 mol % or 55 to 58 mol %, thereby the absolute value of the apparent magnetic anisotropic energy is increased. Accordingly, the magnetic pole at the demagnetization time is stabilized and noise fluctuation is suppressed to a low level.

The magnetocrystalline anisotropic energy Kl is set to not more than 100 J/m.sup.3 and the absolute value of the magnetostriction in the &lt;100&gt; direction, as the magnetic circuit direction, is reduced by appropriately selecting the ferrite material composition. Since the magnetocrystalline anisotropic energy Kl is small, the magnetoelastic energy largely affects the anisotropy of the crystallographic axis. The magnetoelastic energy is made negative and small in magnitude by adjusting the average coefficients of thermal expansion of the ferrite material and glass so as to apply a tensile stress around the magnetic gap of the magnetic head. The &lt;100&gt; direction, i.e., magnetic circuit direction, is thereby allowed to coincide with a hard axis of magnetization. As a result, the permeability of the magnetic head is improved at high-frequency bands.

An orientation film for a liquid crystal display. The film is formed on a substrate and has a first irregular form repeated in a first direction and a second irregular form repeated in a second direction, which is perpendicular to the first direction. The second irregular form has a longer pitch than the pitch of the first irregular form. The profile of the second irregular form in any plane perpendicular to the first direction has a portion inclined with respect to the substrate. The pretilt angle of the orientation film is high. The patterns may be irregular and asymmetric, which may be ridges separated by a continuous groove. The orientation may be formed by using a first mold having one of the patterns, and a second mold with a second pattern, or first and second holographic exposed layers. The orientation layer may be a liquid crystal polymer which is formed by using a heated stamper to form a pattern in a high polymer liquid crystal while applying a voltage.

Orientation film of liquid crystal having bilaterally asymmetric ridges

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Niigata-ken, Japan

Hiroshi Yamagami