Continuous liquid interface production with force monitoring and feedback

Abstract

A method of making a three-dimensional object () is carried out by: (a) providing a carrier () and an optically transparent member () having a build surface, the carrier () and the build surface defining a build region therebetween, the optically transparent member () carrying a polymerizable liquid (); (b) advancing the carrier () and the optically transparent member () away from one another to draw the polymerizable liquid () into the build region; then (c) optionally, partially retracting the carrier () and the optically transparent member () back towards one another; and then (d) irradiating the build region with light to form a growing three-dimensional object () from the polymerizable liquid (); and then (e) cyclically repeating steps (b) to (d) while maintaining a continuous liquid interface () between the growing three-dimensional object () and the optically transparent member () until at least a portion of the three-dimensional object () is formed, while during at least some of the cyclically repeatings: (i) monitoring a transient increase in tension between the carrier () and the build surface through the growing three-dimensional object () during the advancing step (b), and optionally monitoring a transient increase in compression between the carrier () and the build surface through the growing three dimensional object during the partially retracting step (c); and then, when the transient increase in tension has substantially subsided, (ii) initiating the partially retracting step (c) when present, or initiating the irradiating step (d).