Optical microlenses have been developed for 30 years, and thus are widely used in various application fields including imaging, optical communication, optical interconnection, sensors, and so on. Traditional optical microlenses, which are usually fabricated by common optical materials such as typical glasses or silicon materials, have generally immobile shape and fixed focal length and focus distribution over the focal plane of the lens. But it has certain limitations because of the fixed optical properties, for example, a zoom lens for a CCD or CMOS camera need a change of the focal length or the lens power achieved by mechanical movements of several individual lenses in lens system. Current research demonstrates that liquid crystal (LC) is a kind of excellent electro-optic materials, because they have relatively large electrical and optical anisotropies, and their optical properties can easily be shifted by external electric fields applied. Compared to traditional optical microlenses, the focal length of LC microlenses can be changed according to the variance of the alternating signal voltage applied over the LC microlenses. A relatively wide range adjustable and precise output voltage signal can be utilized to perform well in the controlling LC microlenses array, because the variance of focal length can be set in a relatively large range when the voltage of the signal is varied in a relatively large dynamic region. According to the above demands, a digital control device with a wide-range adjustable precise output voltage is designed and realized for LC lens.