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:
Oct. 12, 1999
Filed:
Oct. 28, 1997
FDK Corporation, , JP;
Abstract
Disclosed is a magneto-optical element material composed of a magnetic garnet single crystal which is small in temperature dependency of a Faraday rotation angle, capable of being formed into a film by the LPE, and significantly small in wavelength dependency of a Faraday rotation angle in a specific composition region defined by. The magneto-optical element material is composed of a magnetic garnet single crystal expressed by a composition formula of R.sub.3-x Bi.sub.x Fe.sub.5-v-w-y Ma.sub.v Mb.sub.w Co.sub.y O.sub.12 where R indicates a rare earth element including yttrium, Ma is a trivalent cationic element, and Mb is a tetravalent cationic element; and x, y, v and w satisfy relationships of 0.6.ltoreq.x.ltoreq.1.9, 0.01.ltoreq.y.ltoreq.0.47, 260y-88x+45.ltoreq.0, 500y-30x+37.ltoreq.0, 0.ltoreq.v.ltoreq.1.0, and 0.ltoreq.w.ltoreq.0.35. The material satisfying the following relationships of 0.01.ltoreq.y.ltoreq.0.28 and 800y-130x+45.ltoreq.0 specifically shows improvement in a wavelength dependency of a Faraday rotation angle. Further disclosed is a Faraday element formed by superimposing an A film on a B film for broadening a usable wavelength band region using difference in wavelength dependency of a Faraday rotation coefficient between both the films A and B. The A film is made, by the LPE, from a Bi-substitution type rare earth-iron garnet single crystal not containing Co and the B film is made, by the LPE, from a rare earth-iron garnet single crystal containing Co.