CONTROL DEVICE FOR RUBBING TREATMENT OF SUBSTRATE FOR LIQUID CRYSTAL DISPLAY ELEMENT

摘要

PURPOSE:To control rubbing treatment with good accuracy by winding a ''Permalloy'' leaf between the roll supporting shaft and roll material of a rubbing roll and providing a magneto-resistance element (constituting a means for controlling a proximity distance) which detects the proximity of the ''Permalloy'' leaf on the surface of a surface plate. CONSTITUTION:A glass substrate 9 with the oriented film faced upward is set on a surface plate 3 and a driving source is actuated to advance a rubbing roll 2 toward the plate 3. A magneto-resistance element 8 detects a ''Permalloy'' leaf 5 approaching to said element together with the roll 2 and transmits an output signal. The output is larger as the proximity distance (the distance between the roll 2 and the substrate 9) of the leaf 5 with respect to the element 8 is smaller. The contact condition of the roll 2 with the substrate 9 is thus quantitatively detected from the output of the element 8 and the operation of the driving source is stopped when the output attains a prescribed position. The rubbing treatment is performed in this state. The rubbing pressure is thus controlled with good accuracy and the higher duty is achieved.