Advanced electrode geometry for liquid crystal adaptive lenses

The liquid crystal adaptive lens (LCAL) is an electro-optical device which utilizes a graded index of refraction to bring light to a focus. A set of electrodes control the index variation in a liquid crystal thin film. Previous researchers have analyzed this LCAL extensively and identified two sets of phase aberrations which prevented the LCAL from having a near diffraction-limited performance. One set is called the static phase aberration (which are built-in upon device construction due to the electrode geometry), while the other set is called the dynamic phase aberration (inaccurate applied voltages which could be dithered, or adjusted during operation). Since the static phase aberration is created by the discrete nature of the electrodes, a conductive meshing (CM) method was developed which promised to eliminate any discrete electrodes. Instead of the traditional isolated electrodes, the CM design has a uniformly conducting electrode with multiple driving points. Although CM is very promising, it posed some technical difficulties in controlling ITO thickness during multiple depositions. To circumvent this difficulty, we developed conductive ladder meshing (CLM), a hybrid of the CM and the conventional architecture