Resin cassettes with liquid inhibitor beds to minimize ghosting during additive manufacturing

An apparatus for manufacturing an object from a light polymerizable resin, comprising:

• (a) a carrier platform on which an object can be produced;
• (b) a resin cassette configured for carrying a light-polymerizable resin, said cassette including a light-transmissive window, said window having a liquid inhibitor supply bed therein, said supply bed having an inlet and a supply bed inlet and a supply bed outlet;
• (c) a light source positioned beneath said resin cassette and configured for projecting an enlarged image through said window;
• (d) a drive operatively associated with said resin cassette and said carrier platform and configured for advancing said carrier platform and said resin cassette away from one another;
• (e) a gas exchanger comprising a liquid side, a gas side, and an oxygen permeable barrier therebetween;
• said liquid side having a liquid side inlet and a liquid side outlet, with said supply bed inlet connected to said liquid side outlet, and said supply bed outlet connected to said liquid side inlet;
• (f) an oxygen carrying liquid in said liquid inhibitor supply bed and said gas exchanger liquid side;
• and (g) a pump operatively associated with said liquid inhibitor supply bed and said gas exchanger liquid side for circulating said oxygen carrying liquid therebetween;
• and (h) an oxygen gas source operatively associated with said gas exchanger gas side.