An exposure system for fabricating optical film such as for photoalignment, where the optical film has a photosensitive layer and a substrate. The assembly comprising a fire box having an interior area, a baffle in the interior area defining lower and upper combustion chambers relative to the baffle. In other words, high concentration regions where impurity concentrations are higher than that at a central portion in the end parts of the channel formation portion on the side of a source and a drain. In an implementation, two materials, the first an ink depositing amine and the second an ink depositing epoxy, are printed separately. These iterations are repeated until a termination condition is reached.