Miniaturized microparticles

1. A microparticle comprising:

a plurality of segments aligned along an axis, wherein the plurality of segments define a code for the microparticle;

an outer cuboid encapsulating the plurality of segments, wherein the plurality of segments are detectable through the outer cuboid.

2. The microparticle of claim 1 , wherein the plurality of segments comprise:

a first cuboid segment; and

a second cuboid segment, wherein the first cuboid segment and the second cuboid segment have the same cross section shape.

3. The microparticle of claim 2 , wherein the first cuboid segment and the second cuboid segment have different lengths.

4. The microparticle of claim 1 , wherein the plurality of segments are opaque and the outer cuboid is transparent.

5. The microparticle of claim 1 , wherein a volume of the microparticle is 20,000 cubic microns or less.

6. The microparticle of claim 1 , wherein a length of the microparticle is 160 microns or less.

7. The microparticle of claim 1 , wherein the outer cuboid has a substantially square cross-section along its length.

8. An encoded microparticle comprising:

an outer cuboid, wherein the outer cuboid has a substantially square cross section taken orthogonal to the length of the microparticle; and

opaque and transparent segments, wherein the opaque and transparent segments form a code of the microparticle, and wherein each of the opaque segments is enclosed within the outer cuboid.

9. The microparticle of claim 8 , wherein the opaque and transparent portions alternate along the length of the microparticle.

10. The microparticle of claim 8 , wherein the microparticle comprises at least two opaque segments.

11. The microparticle of claim 8 , wherein the opaque portion is composed of amorphous silicon.

12. The microparticle of claim 11 , wherein the transparent portion comprises silicon dioxide.

13. The microparticle of claim 8 , wherein the microparticle has a maximum length dimension of 160 microns.

14. The microparticle of claim 8 , wherein the outer cuboid and the transparent segments are comprised of the same material.

15. A microparticle comprising:

a first material comprising two or more segments aligned along an axis; and

a second material, wherein the second material forms an outer cuboid enclosing the first material.

16. The microparticle of claim 15 , wherein

the first material is opaque and the second material is transparent.

17. The microparticle of claim 15 , wherein the two or more segments aligned along the axis are cuboid segments.

18. The microparticle of claim 15 , wherein the outer cuboid has a square cross section shape orthogonal to a length of the microparticle.

19. The microparticle of claim 15 , wherein the microparticle has a maximum length dimension of 160 microns.