Ellipse construction, Continued
The conjugate diameter method of ellipse construction uses conjugate
diameters to project a circle and through a series of tangents, plot points on
the circumference of the ellipse.
To construct an ellipse using conjugate diameters, use this table;
Given two conjugate diameters (AB and DE) with C as a center,
use the distance from C to A as a radius to draw a circle with C as
Draw line (GF) perpendicular to AB and passing through C.
Draw lines connecting points D and F and points G and E.
Select any point (X) along AB and draw a line (PQ) parallel to DE
and RS parallel to FG.
Determine at least five points to each quadrant. For larger ellipses,
plot more points. The more points plotted the more accurate the
Lightly sketch the outline of the ellipse. Darken the ellipse using
Figure 2-50 illustrates the conjugate diameter method of ellipse construction.
Continued on next page