Apparatus and method for generating a variable line width

DETAILED DESCRIPTION What is claimed is: 1.
An apparatus for drawing with an ink pen having a radially asymmetric nib, comprising: a.
a plotter having: i.
a table for receiving medium upon which said pen will draw; ii.
a pen slider translatable with respect to said table parallel a first axis (nominally designated the "X" axis); and iii.
a pen holder for receiving said pen, mounted on said slider and translatable with respect to said slider parallel a second axis (nominally designated the "Y" axis), orthogonal to said first axis, said pen holder including means for maintaining said pen substantially parallel to and at a known angular orientation with respect to a third axis (nominally designated the "Z" axis) perpendicular said X and Y axes and said pen is rotatable about said Z axis; and b.
means for selectively varying the angular orientation of said pen nib with respect to said Z axis, thereby controlling said pen to apply ink of selectable and variable widths along a line independent of the shape of the line or its orientation with respect to the X and Y axes.
2.
The apparatus of claim 1, wherein said means for selectively varying the angular orientation of said pen nib comprises: a.
a means for position indexing having an output member that indexes through preselectable positions; and b.
means for mechanically linking said output member of said indexing means with said rotatable pen such that a position of said output member corresponds to a predetermined angular orientation of said pen.
3.
The apparatus of claim 2, further comprising a digital computer which controls said means for selectively varying the angular orientation of said pen nib.
4.
The apparatus of claim 3 wherein said means for indexing comprises a stepping motor.
5.
The apparatus of claim 4 wherein said means for mechanically linking said output member to said rotatable pen comprises a flexible sheathed cable.
6.
The apparatus of claim 5 wherein said pen comprises: a.
a first cylindrical tube connectable to said pen holder and maintainable at a fixed angular orientation with respect to said Z axis; and b