The gap between the electrodes and the electro-optic element of a proximity coupled electro-optic device, such as a multi-gate light valve for an electro-optic line printer, is filled with a dielectric having a relative dielectric constant (i.e., the dielectric constant relative to that of air) which...http://www.google.de/patents/US4370029?utm_source=gb-gplus-sharePatent US4370029 - Dielectric interface for proximity coupled electro-optic devices
