Abstract
A photofluidic interface is a new fluidic device which transduces optical control signals to pneumatic or hydraulic control signals. Up to now two kinds of device have been proposed and one of them was developed by B. Hockaday, et al. in 1983. Although this device has the advantage of producing a larger response than the other, the principle of its operation is not fully understood.
In this paper, the static and dynamic characteristics of this type of interface were investigated experimentally and theoretically. A He-Ne laser beam of 5∼40mW was focused into the flow in the supply nozzle edge of the device. The following results were obtained: 1. By the experiment with air or water as a working fluid, the measurement of the temperature change at and around a focal point, and the analytical flow model, it was made clear that the heat generated by light changed the fluid viscosity locally, and this caused a difference in output pressure. 2. The proposed analytical model can make reliable predictions about the effects of focal point, nozzle width, and splitter distance on the relation between optical power and output differential pressure. 3. The frequency response of the interface was measured and the band width was 150Hz.
