Optical system and method for reading encoded microbeads

1. An optical system comprising:

microbeads that are structurally distinct and capable of moving independently with respect to one another, the microbeads being encoded and configured to provide output light signals onto a Fourier plane when illuminated by an incident light;

an input light source configured to illuminate the structurally distinct microbeads thereby providing the output light signals, the output light signals configured to be projected onto the Fourier plane in a readable manner;

a reading device positioned to detect the output light signals from the Fourier plane;

a processor configured to perform Fourier plane analysis of the optical light signals to determine corresponding codes of the microbeads; and

a support substrate configured to receive a plurality of the microbeads that are randomly distributed along the support substrate.

2. An optical system of claim 1 , wherein the support substrate is configured to orient the microbeads in a predetermined manner for when the microbeads are illuminated.

3. An optical system of claim 1 , wherein the system is configured to orient the microbeads in a predetermined manner for when the microbeads are illuminated.

4. An optical system of claim 1 , wherein the output light signals are projected on the Fourier plane by scattering incident light off or through the microbeads.

5. An optical system of claim 1 , wherein the reading device includes a charge coupled device (CCD).

6. An optical system of claim 1 , further comprising a transform lens that is configured to be arranged between the microbeads and the Fourier plane at a distance of about one focal length f from the Fourier plane and at a distance of about one focal length f from the microbeads.

7. An optical system of claim 1 , wherein the processor determines the codes based upon detected Fourier components from the output light signals.

8. An optical system of claim 7 , wherein information is contained in both a power amplitude and spatial frequency of the Fourier components, the processor analyzing the power amplitude and the spatial frequency of the Fourier components.

9. An optical system of claim 1 , wherein the corresponding codes are determined by looking at a presence or absence of predetermined Fourier spatial frequencies.

10. An optical system of claim 1 , wherein the output light signals on the Fourier plane form corresponding bar codes or digital images, the respective codes on the microbeads being unintelligible as the corresponding bar code or the corresponding digital image.

11. A system according to claim 1 , further comprising a detector configured to detect fluorescence from the microbeads.

12. A system according to claim 1 , wherein the processor is configured to identify locations of the randomly distributed microbeads.

13. A system according to claim 1 , wherein the processor identifies respective substances that are associated with the microbeads based upon the code.

14. A system according to claim 1 , wherein the processor includes one or more microprocessor-based architectures.

15. An optical system comprising:

microbeads that are structurally distinct and capable of moving independently with respect to one another, the microbeads being encoded and configured to provide output light signals onto a Fourier plane when illuminated by an incident light;

an input light source configured to illuminate the microbeads thereby providing the output light signals, the output light signals configured to be projected onto the Fourier plane in a readable manner;

a reading device positioned to detect the output light signals from the Fourier plane; and

a processor configured to perform Fourier plane analysis of the optical light signals to determine corresponding codes of the microbeads, wherein the processor identifies chemical probes immobilized to the microbeads based upon the code.

16. A method for reading encoded microbeads, comprising:

providing a plurality of microbeads having individually identifiable codes, the microbeads being structurally distinct and capable of moving independently with respect to one another, the microbeads being provided onto a support substrate and randomly distributed along the support substrate;

illuminating the microbeads with an incident light, the codes providing corresponding output light signals indicative of the respective codes, the corresponding output light signals of the microbeads being projected on a Fourier plane; and

reading the respective codes from the Fourier plane.

17. A method according to claim 16 , wherein the output light signals are projected on the Fourier plane by scattering the incident light off or through the microbeads.

18. A method according to claim 16 , wherein each of the codes comprises a variation in at least one of an effective refractive index or optical absorption of the respective microbead.

19. A method according to claim 18 , wherein the variation in at least one of the effective refractive index or optical absorption is located within an inner region that is surrounded by an optically transparent outer region.

20. A method according to claim 16 , further comprising identifying the microbeads by looking at a presence or absence of predetermined Fourier spatial frequencies.

21. A method for reading encoded microbeads, comprising:

providing a plurality of microbeads having individually identifiable codes;

illuminating the microbeads with an incident light, the codes providing corresponding output light signals indicative of the respective codes, the corresponding output light signals of the microbeads being projected on a Fourier plane; and

reading the respective codes from the Fourier plane, wherein the codes of the microbeads are correlated to chemical probes that are immobilized to the microbeads, the method further comprising identifying the chemical probe using the code.

22. A method according to claim 21 , further comprising determining whether the chemical probes have selectively bound to a target analyte after the microbeads are exposed to the target analyte.