In this paper, an electrically tunable-focusing and polarizer-free liquid crystal (LC) lens for ophthalmic lenses is demonstrated. The optical operating principles of the LC lens in a human eye system are introduced and the optical principle of the polarization independent of the double-layered LC lens is investigated. The polarization dependency, image quality and the response time of the double-layered LC lens are measured. The continuously tunable-focusing properties of the LC lenses are more practical in applications for different visional conditions of people. The concept in this paper can also be extensively applied to imaging systems, and projection systems, such as cameras in cell phones, pico projectors, and endoscopes.