  Focusing optics for neutral molecules finds application in shaping and
steering molecular beams. Here we present an electrostatic elliptical mirror
for polar molecules consisting of an array of microstructured gold electrodes
deposited on a glass substrate. Alternating positive and negative voltages
applied to the electrodes create a repulsive potential for molecules in
low-field-seeking states. The equipotential lines are parallel to the substrate
surface, which is bent in an elliptical shape. The mirror is characterized by
focusing a beam of metastable CO molecules and the results are compared to the
outcome of trajectory simulations.
