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US 4,904,349 AGranted
Methods for producing optomagnetic recording media and systems for their use
AssigneeNippon Gakki Seizo Kabushiki Kaisha
InventorsTadao Tokushima, Makoto Shiraki
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Abstract
In production of an optomagnetic recording medium having a porous anode oxidized coat on a base plate, a thin film of magnetic material of high saturated magnetization is developed after grinding and etching following formation of the anode oxidized coat in order to increase the effective reflection plane, thereby greatly raising accuracy of detection of the polarization angle at reading-out of signals.
Claims8
A method for producing an optomagnetic recording medium, comprising the steps of:
- forming a base plate comprising aluminum;
- applying anode oxidation to a surface of said base plate to form a porous anode oxidized coat thereon;
- packing a first magnetic material in pores in said anode oxidized coat;
- grinding said surface of said anode oxidized coat until exposed ends of said first magnetic material in said pores are substantially flush with said anode oxidized coat immediately surrounding said pores;
- and after said grinding,
- depositing a thin film of a second magnetic material having a saturation magnetization of at least about 0.5 T on at least said exposed ends of said first magnetic material and on at least said anode oxidized coat immediately surrounding said pores.
3 more elements
Dependencies are inferred from the claim text.