Design and simulation of adaptive beam steering actuated by hydraulic polymer elastic membrane

There is a strong demand for beam steering aiming to reposition an optical beam in various fields of applications, such as optical communications, light detection and ranging, microscopies, displays. In this paper, we present a beam steering method actuated by a hydraulic polymer elastic membrane. A thick polydimethylsiloxane (PDMS) membrane is placed underneath a thin PDMS membrane. The beam steering angle can be varied adaptively through inputting different hydraulic pressure. The thin PDMS membrane deforms significantly and the thick PDMS membrane deforms slightly since there is enough thickness difference between thick and thin PDMS membrane when the liquid pressure is applied. The model of the adaptive beam steering method is built and some simulation experiments are carried out by COMSOL Multiphysics software. The effects of some model parameters are analyzed. The parameters include the thickness ratio, the distance between the thick PDMS membrane and the acrylic frame, the length of the thick PDMS membrane, and liquid pressure are studied. We can find that the linearity of the effective refractive surface increases with the increase of thickness ratio and decreases when the thick PDMS membrane is close to the acrylic frame. The beam steering angle increases with increasing of the liquid pressure. We also find that there is a tradeoff between the length of the thick PDMS membrane and the range of the beam steering angle. The results show that the appropriate thickness ratio of the thick and thin PDMS membrane is 7:1. The beam steering angle is 0°~33.46° when the liquid pressure is 0 kPa~8 kPa. The length of the thick PDMS membrane is 7.5 mm. This paper can be used to design an adaptive beam steering device actuated by the hydraulic pressure.