  In this paper we present a Deformable Mirror (DM) based on the continuous
voltage distribution over a resistive layer. This DM can correct the low order
aberrations (defocus, astigmatism, coma and spherical aberration) using three
electrodes with nine contacts leading to an ideal device for sensorless
applications. We present a mathematical description of the mirror, a comparison
between the simulations and the experimental results. In order to demonstrate
the effectiveness of the device we compared its performance with the one of a
multiactuator DM of similar properties in the correction of an aberration
statistics. At the end of the paper an example of sensorless correction is
shown.
