The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 13, 2004
Filed:
Mar. 09, 2001
Kunio Kojima, Nabari, JP;
Masaki Hamamoto, Toshima-ku, JP;
Junichi Satoh, Nara, JP;
Hiroyuki Katayama, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A composite magnetic head device includes a recording head and a reproducing head for magnetically recording and reproducing information on and from a recording medium, and further includes heat sources for heating the recording medium when recording and reproducing. As the heat sources, diffraction grating patterns for the recording head and the reproducing head are formed independently. With this structure, when recording and reproducing information based on the thermal distribution of the recording medium heated by the heat sources, the thermal damage on the recording medium can be suppressed, and the likelihood of such problem that the recording medium is heated too much and the information recorded in the heated portion are erased can be prevented.