Liquid crystal optical modulator device with each electrode width smaller than both the liquid crystal thickness and the electrode gaps

An optical modulator device comprising:

• a pair of transparent insulating substrates having opposed surfaces;
• two groups of fine linear electrodes, each linear electrode being spaced from an adjacent linear electrode by a gap, each group being disposed opposite the other in a parallel and evenly spaced pattern on a surface of a respective one of the pair of transparent insulating substrates, each of said linear electrodes having a central axis with a height being periodically changed in a waveform as a function of space;
• and
• a liquid crystal layer sandwiched between the pair of said transparent insulating substrates, said liquid crystal layer being divided into a plurality of pixels having a matrix arrangement by said opposite electrode patterns, a continuous spatial modulation pattern being formed at the electrode gap regions encompassed by the plurality of said adjacent fine electrodes by driving said plurality of pixels by a transverse electric field upon impressing a voltage on said fine electrodes;
• each said electrode having a width and a gap between adjacent electrodes smaller than the thickness of said liquid crystal layer.

A method of forming a continual spatial modulation pattern, the method comprising the steps of:

• arranging two groups of fine electrodes in parallel evenly spaced patterns on opposed transparent insulating substrates, the fine electrodes each having a characteristic width, and the distance between adjacent fine electrodes comprising a characteristic gap;
• providing a liquid crystal layer sandwiched between the substrates, the thickness of the crystal layer being larger than the characteristic electrode width and the characteristic electrode width being smaller than the gap distance between adjacent fine electrodes;
• selecting the fine electrodes;
• and
• impressing a voltage on the selected fine electrodes to form the spatial modulation pattern encompassing the area defined by the selected fine electrodes, and the characteristic gaps formed by the selected fine electrodes on one substrate and the opposite substrate being driven by a transverse electric field.