that the liquid crystal molecules proximate the surface are induced to a predetermined pretilt angle application_number US 6757498 A description fig1 is a schematic of the physical and electrical configuration of a preferred ion source for the ion beam system 1 used to produce the liquid crystal cell of the present invention the principals of operation of the system are best understood by realizing that an ion source consists of three regions ions are generated in the discharge plasma region 12 accelerated through the extraction region 6 and travel through the beam plasma region 44 ions are generated in the discharge plasma region 12 by electron bombardment of neutral gas atoms electrons are emitted by a hot filament cathode 8 driven by a current source i c 10 and accelerated by a potential difference v d 20 between the cathode 8 and the anode 14 preferably a low energy beam of argon ions is used to bombard the surface of a polyimide film layer 24 the argon beam produces directional alignment when the beam is at an angle other than perpendicular to the surface because neutral beams of energetic particles can also cause damage of the polyimide resulting in broken bonds which provide a deleterious time dependent response in the liquid crystal when a voltage is applied to operate the display it is highly desirable to use a low energy beam of energies comprising greater than 25 volts rather than the hundreds of volts described in the literature see e g u s pat no 5 030 322 issued july 1991 to shimada et.