Relationship between liquid crystal layer thickness and variable-focusing characteristics of an ultrasound liquid crystal lens

The effect of the liquid crystal (LC) layer thickness on the optical characteristics of an ultrasound LC lens was explored. Three LC lenses with differing LC layer thicknesses (100, 200, and 300 µm) were fabricated, and the optical focal lengths were measured by an optical microscope with a varying driving voltage. For the lens with a 200-µm-thick LC layer, a larger change in the focal length was observed for a smaller driving voltage compared with that of the other two lenses, indicating that the LC layer thickness is appropriate for a variable-focus lens.

Liquid crystal lens with four driving voltages and its applications in imaging system with rectangular aperture

Liquid crystal lens has the characteristic of variable focal length. Many studies have demonstrated that electronically controlled focusing without mechanical movements can be realized by using liquid crystal lenses in imaging system. In this paper, a four-electrodes liquid crystal lens with a rectangular aperture is applied to focus. The aperture’s aspect ratio of the liquid crystal lens can be designed arbitrarily so that installing it with the periscope lens in phones becomes possible.