US 12,271,009 B2
Retro-reflective marker with uniformly distributed microelements
Shaulaine White, Troy (CA); Derek Peter Zwambag, Guelph (CA); Larry Chen, Fergus (CA); and Athanasios Tommy Balkos, Waterloo (CA)
Assigned to Northern Digital Inc., Waterloo (CA)
Filed by Northern Digital Inc., Waterloo (CA)
Filed on May 24, 2024, as Appl. No. 18/674,190.
Claims priority of provisional application 63/525,382, filed on Jul. 7, 2023.
Prior Publication US 2025/0012953 A1, Jan. 9, 2025
Int. Cl. G02B 5/124 (2006.01)
CPC G02B 5/124 (2013.01) 30 Claims
OG exemplary drawing
 
1. An apparatus comprising:
a retro-reflective section in a curved shape, the retro-reflective section comprising:
an outer surface,
an inner surface, and
a plurality of retro-reflective microelements comprising a plurality of reflective surfaces, wherein each of the plurality of retro-reflective microelements extends from the inner surface at a location different from locations of the other retro-reflective microelements, and each of the plurality of retro-reflective microelements comprises a central axis extending along a direction that corresponds to a surface normal of the outer surface,
wherein each of the plurality of retro-reflective microelements comprises two or more planar angles that are perturbed away from a reference angle by a respective value of a predetermined range.