Optics

This example illustrates a simulation of the opto-electro-thermo-mechanical actuation of a bi-layer micro-mirror. This mirror is composed of two layers made of materials with different thermal expansion coefficients. The extremity of an “arm” of the system is submitted to a given electric potential while the others have a null potential. Due to this difference of potential between the different extremities, a current appears through the system and causes heating by joule effect. Because the thermo-mechanical behavior of the two layers is different, a bending effect appears and it is possible to control the elevation of the device by modifying the applied voltage. The optical impact of mirror displacement is then obtained.

A support was generated around two mirrors that are defined in a ZEMAX provided design. The complete structure is cooled. The impact of the material used for the support of the two first mirrors (off-axis design) was analysed. In this particular case, a change from aluminium to titanium for the support reduces by a factor 4 the perturbation of the merit function value.

The impact of the direction of a pressure load applied on the support of a parabolic reflector can be evaluated. The applied force at the support induces a tilt motion of the mirror. The identification of the rigid body motion parameters enables highlighting pure elastic deformations hidden by the magnitude of the rigid body motion.