Towards non-mechanical wide angle fovea sensor — Fundamental design by liquid crystal lens cell

The authors aim at developing a wide angle fovea sensor by which a gaze point and magnification around it are variable in a field of view (FOV) without mechanical parts. Moreover, this sensor can gaze at not only a single point but also multiple points simultaneously. In order to achieve these functions, we apply liquid crystal (LC) for lens materials and control its distribution of optical refraction. As the first step, this paper introduces a prototype of a LC wide-angle fovea lens, in which the magnification around the central FOV of the LC lens cell is controlled electrically as maintaining its image angle of the FOV. In general, as the LC lens cell responds more quickly, it becomes harder to change the distribution of the optical refraction largely. The authors have developed a special-made wide-angle input lens and have combined it with the LC lens cell in order to achieve both the large change and the quick response. In addition, this paper introduces an experimental environment built up for observing projection images and fringe patterns of the LC fovea lens.