Testing And Analysis Of The Performance Of The Liquid Lens Based On Electrowetting Effect

The focal length of the electric liquid lens based on the Electro-Wetting changes with appliedvoltage, which can be changed without mechanical movement. So the electric liquid lens has beenthe focus of research in recent years.This paper introduces the principle and structure of the liquid lens which based on the electricwetting effect in detail, and successfully made the electric liquid lens with metal side wall. Thepaper presents the design of the device to test the performance of the electric liquid lens, whichconsists of a helium neon laser, liquid lens, pore apertures, photoelectric balance of receiver andoscilloscope. According to the Gaussian beam transmission and lens transformation principle thispaper analyzes the theory of test mechanism in detail. The luminous flux which enters thephotoelectric balance detector will change by the focal length of the lens and the output of theoscilloscope corresponding to the focal length of the lens will change too. This device can be usedto measure the dynamic process and response time of the variational focal length of the liquid lens.This paper studies the influence of the size and position of the pore apertures to the performance ofthe test device. The results show that the diaphragm should be placed on beam waist place of theprobe beam when it passes the liquid lens. The diameter of the small aperture takes0.05mm. Thispaper developed a liquid lens performance testing device based on the design proposal andmeasured the variational properties of the liquid lens with the frequency of the50HZ alternatingcurrent. The results show that with the increase of voltage, there are four periodic signals appear inproper order whose frequency is50HZ and the value of the four signals will increase with theincreasing voltage. The polarity of the applied voltage will influence the signal to a certain extent.When the applied voltage is lower, the shape of the liquid level will change according to thespherical with the time. When the applied voltage is higher, the liquid level will produce oscillation,the shape of the liquid level will no longer change by spherical.