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:
Jul. 22, 2003
Filed:
Dec. 10, 2001
Abstract
A phase-conjugate holographic data storage device capable of enhancing the characteristics of recording and reproducing data by using a focusing lens is provided. The holographic data storage device includes a focusing lens which focuses an object beam having data, a spatial light modulator which is located on the optical path of the object beam passing through the focusing lens and modulates the object beam, and a data recording medium which records an interference pattern generated by interference between a reference beam and the object beam passing through the spatial light modulator and converging into a focus. The focusing lens is a focusing lens having at least two different focuses. The holographic data storage device is capable of effectively reducing a dc term having a bad influence on the characteristics of recording data, minimizing the size of a data unit, that is, a spot, and thus enhancing the density of recording data.