Apparatus and method for marking arcuately configured character strings

Apparatus and method are described for developing indentation defined characters formed within pixel matrices having a generally arcuate configuration. The row and column matrices which are formed by the method are characterized in having arcuate rows which are regularly spaced radially from a marker axis. The column components of the pixel matrices are regularly angularly spaced radii emanating from the same marking axis. A rotational marker head is provided carrying marker pin assemblies which are oriented at regular radial angular spacings and in progressively incrementing regular radial distances from the marker axis. As the marker head assembly is rotated, the marker pin assemblies are actuated to form the arcuate character string. The apparatus and method permits the marking of significant character string information on restricted surfaces such as the face of gears and the like.