Edgar M. Vuelban @ The Optics Research Group. said:
... the use of liquid could be a solution to the problem of low spatial resolution inherent to most solid-state deformable mirrors. Only a few research efforts on liquid-based deformable mirrors have been reported. For the last three decades, only two liquid-based deformable mirrors were proposed and demonstrated. These two design concepts are based on electromagnetic actuation.
This thesis presents a new design concept of a liquid-based deformable mirror, based on electro-capillary actuation. This new design offers advantages compared with solid mechanical mirrors and the other liquid-based deformable mirrors (LDM). These advantages include, among others, 1) a very high umber of actuators, 2) lower power dissipation, 3) low-cost fabrication 4) an initially flat surface, among others.
The proposed LDM consists of an array of vertically oriented capillaries filled with two immiscible liquids, an conducting liquid and a dielectric liquid, where the dielectric liquid overfills the top end of the channels and forms a thin layer on top. A free-floating reflective membrane is utilized to remedy the problem of the low reflectivity of a pure liquid surface.The fundamental issues relating to the proposed device such as the propagation of surface waves on the liquid, how fast the liquid reacts to the actuation signal, and the shape of the surface when deformed are studied numerically.
Numerical simulation shows that the propagation of surface waves can be damped in less than a millisecond depending on the viscosity of the top liquid being used. From the numerical simulation, the response time of the proposed device turns out to be in the order of few milliseconds (¡ 10ms)...