Writing and reading fluorescent optical storage media using Bessel beams
Disclosed are fluorescent optical storage systems that include fluorescent optical media having one or more recordable layers, and a writer configured to direct an excitation beam on the fluorescent optical media. The excitation beam, which is capable of inducing a photochemical reaction in a selected layer of the one or more recordable layers, is generated from a Bessel beam. Such systems are capable of writing a sub-wavelength resolutions, which can be read using stimulated emission depletion. Light sheets may be used to selectively identify layers for writing.
1 . A fluorescent optical storage system comprising:
a fluorescent optical media including one or more recordable layers;
a writer configured to direct an excitation beam on the fluorescent optical media, the excitation beam capable of inducing a photochemical reaction in a selected layer of the one or more recordable layers, wherein the excitation beam is generated from a Bessel beam; and
a light sheet generator configured to produce a light sheet that selectively illuminates the selected layer of the one or more recordable layers to thereby assist in inducing the photochemical reaction in locations where the excitation beam intersects with the light sheet.
2 . The fluorescent optical storage system of claim 1 , further comprising a reader configured to stimulate and to detect fluorescence in one or more of the recordable layers of the fluorescent optical media.
3 . The fluorescent optical storage system of claim 2 , wherein the reader is configured to stimulate fluorescence using a Bessel beam.
4 . The fluorescent optical storage system of claim 2 , wherein the reader is configured to stimulate fluorescence using a beam produced by STED.
5 . The fluorescent optical storage system of claim 1 , comprising an axicon to produce the Bessel beam.
6 . The fluorescent optical storage system of claim 1 , further comprising one or more optical components that condition the Bessel beam to thereby generate the excitation beam.
7 . The fluorescent optical storage system of claim 6 , wherein the one or more optical components includes an aperture.
8 . The fluorescent optical storage system of claim 6 , wherein the one or more optical components includes a STED system.
9 . The fluorescent optical storage system of claim 8 , wherein the Bessel beam is used as an input beam for the STED system.
10 . The fluorescent optical storage system of claim 9 , wherein the Bessel beam is used as a depletion beam input for the STED system.
11 . A method for writing information onto a fluorescent optical storage media, the method comprising the steps of:
forming an excitation beam having a profile characterized by a Bessel function;
directing the excitation beam on a recordable layer of the fluorescent optical storage media to thereby induce a photochemical reaction in the recordable layer at an area illuminated by the excitation beam; and
selectively illuminating the recordable layer with a light sheet that assists the excitation beam in inducing the photochemical reaction in the recordable layer.
12 . The method of claim 11 , wherein the Bessel function is a first order Bessel function.
13 . The method of claim 11 , wherein the Bessel function is a higher order Bessel function.
14 . The method of claim 11 , wherein prior to directing the excitation beam on the recordable layer of the fluorescent optical storage media, the excitation beam is conditioned using one or more optical components.
15 . The method of claim 14 , wherein the one or more optical components comprises an aperture.
16 . The method of claim 14 , wherein the one or more optical components comprises a STED system.
17 . The method of claim 16 , wherein the STED system uses a Bessel beam as an excitation input.
18 . The method of claim 16 , wherein the STED system uses a Bessel beam as a depletion input.