Lamina comprising cube corner elements and retroreflective sheeting

A lamina comprising a row of cube corner elements having face formed from a side groove set wherein the grooves are nominally parallel to each other and range from being nominally parallel to non-parallel to within 1° to reference plane 28.

An article comprising preferred geometry cube corner elements wherein at least one cube comprises a 1-2 dihedral angle error and a 1-3 dihedral angle error;

• wherein the dihedral angle errors vary in opposition.

An article comprising at least one preferred geometry cube corner element having three dihedral angles errors wherein the dihedral angle errors are different from each other.

Retroreflective sheeting comprising a row of preferred geometry cube corner elements having faces defined by a side groove set wherein at least two grooves within the set are nonparallel by amounts ranging from greater than nominally parallel to about 1°.

Retroreflective sheeting comprising a row of preferred geometry cube corner elements having face defined by a side groove set wherein the grooves are nominally parallel to each other and range from being nominally parallel to non-parallel to within 1° to reference plane 28.

Retroreflective sheeting comprising an array of preferred geometry cube corner elements that exhibits an average brightness at 0° and 90° orientation according to ASTM D4596-1a of at least 375 candelas/lux/m2 for an entrance angle of −4° and an observation angle of 0.5°.