LIGHT MODULATOR

摘要

A light modulator comprises liquid crystal material (6) sandwiched between two substrates (2, 4) each bearing a set of electrodes, the sets crossing each other to define a matrix of pixels. A plurality of pixel areas having different switching thresholds is achieved by one or both of the sets of electrodes comprising a set of primary electrode portions (10) separated from a set of secondary electrode portions (12) by an insulating layer (11), each secondary electrode portion (12) being connected to the corresponding primary electrode portion (10) by a plurality of connection members (13) extending through the layer (11). The structure presents a substantially flat surface to enable the liquid crystal layer (6) to be of uniform thickness and thus simplify the definition of the switching thresholds. In addition, the electrode material remains thin so that it offers less impedance to the passage of light. The secondary electrode portions (12) may be positioned so as to overlie the spaces (18) between the primary electrode portions (10), which may obviate the need for a black mask.