  The paper is devoted to differential geometric invariants determining a
Frenet curve in up to a direct similarity These invariants can be presented by
the Euclidean curvatures in terms of an arc lengths of the spherical
indicatrices. Then, these invariants expressed by focal curvatures of the
curve. And then, we give the relationship between curvatures of evolute curve
and shape curvatures. Morever, these invariants is given the geometric
interpretation.
