Micro-Fresnel zone plate optical devices using densely accumulated ray points
First Claim
1. An optical device suitable for use with an optical medium for the storage and retrieval of data, the optical device comprising:
- an illumination means for providing a beam of optical radiation of wavelength λ
;
an optical path that the beam of optical radiation follows; and
a single planar diffractive optical element configured to comprise a plurality of annular sections comprising a first material alternately disposed with a plurality of annular sections comprising a second material or a different thickness of the first material, wherein the diffractive optical element is configured to generate a plurality of diffractive focal points and a plurality of densely accumulated ray points on an optical axis away from the diffractive optical element; and
an optical medium positioned at a selected densely accumulated ray point which is surrounded by one or multiple of zero-light-intensity destructive interference ring patterns that are located near the optical axis away from the diffractive optical element.
2 Assignments
0 Petitions
Accused Products
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.
59 Citations
8 Claims
-
1. An optical device suitable for use with an optical medium for the storage and retrieval of data, the optical device comprising:
-
an illumination means for providing a beam of optical radiation of wavelength λ
;an optical path that the beam of optical radiation follows; and a single planar diffractive optical element configured to comprise a plurality of annular sections comprising a first material alternately disposed with a plurality of annular sections comprising a second material or a different thickness of the first material, wherein the diffractive optical element is configured to generate a plurality of diffractive focal points and a plurality of densely accumulated ray points on an optical axis away from the diffractive optical element; and an optical medium positioned at a selected densely accumulated ray point which is surrounded by one or multiple of zero-light-intensity destructive interference ring patterns that are located near the optical axis away from the diffractive optical element. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
Specification
-
- Resources
-
Current AssigneeUnited States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
-
Original AssigneeUnited States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
-
InventorsElliott, James R., Park, Yeonjoon, Choi, Sang H., King, Glen C.
-
Primary Examiner(s)Young; Wayne
-
Assistant Examiner(s)BERNARDI, BRENDA C
-
Application NumberUS12/490,747Publication NumberTime in Patent Office811 DaysField of Search369/44.26, 369/109.01, 369/112.01, 369/112.03, 369/112.2, 359/565, 359/569US Class Current369/112.03CPC Class CodesG11B 2007/0006 adapted for scanning differ...G11B 2007/13722 Fresnel lensesG11B 7/1353 Diffractive elements, e.g. ...G11B 7/1374 Objective lenses optical ob...
