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:
Nov. 22, 1988
Filed:
Feb. 12, 1987
Applicant:
Inventors:
Shigeyuki Hosoki, Hachioji, JP;
Keiji Takata, Koganei, JP;
Toshiyuki Aida, Chofu, JP;
Sumio Hosaka, Nishitama, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01J / ;
U.S. Cl.
CPC ...
346158 ; 3461531 ;
Abstract
An electron beam recording and reproducing apparatus which radiates the electron beam emitted from a needle cathode to a disc for recording and reproduction is disclosed. The needle cathode moves on the disc. A magnetic field is applied in the axial direction of the needle cathode in order to converge and radiate the electron beam emitted from the needle cathode to the disc.