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:
Sep. 13, 2011
Filed:
Jun. 24, 2009
Sang H. Choi, Poquoson, VA (US);
Yeonjoon Park, Yorktown, VA (US);
Glen C. King, Williamsburg, VA (US);
James R. Elliott, Vesuvius, VA (US);
Sang H. Choi, Poquoson, VA (US);
Yeonjoon Park, Yorktown, VA (US);
Glen C. King, Williamsburg, VA (US);
James R. Elliott, Vesuvius, VA (US);
Abstract
An embodiment generally relates to an optical device suitable for use with an optical medium for the storage and retrieval of data. The optical device includes an illumination means for providing a beam of optical radiation of wavelength λ and an optical path that the beam of optical radiation follows. The optical device also includes a diffractive optical element defined by a plurality of annular sections. The plurality of annular sections having a first material alternately disposed with a plurality of annular sections comprising a second material. The diffractive optical element generates a plurality of focal points and densely accumulated ray points with phase contrast phenomena and the optical medium is positioned at a selected focal point or ray point of the diffractive optical element.