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. 26, 1999
Filed:
Dec. 06, 1995
Yoshihiko Okamoto, Ohme, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Technology for forming a fine light beam having a size smaller than the theoretical limit determined by the wavelength of light and characteristics of an objective lens. A beam distribution shifter having two light transmission regions is disposed between a source of light and an objective lens, a phase shifter is provided on one of the two light transmission regions to divide the light passing through the beam distribution shifter into two light fluxes having phases opposite to each other, and the two light fluxes are focused through the objective lens to form a fine light beam having a size smaller than the theoretical limit determined by the wavelength of the light and characteristics of the objective lens due to destructive interference between the two light fluxes.