Patent ID: 11919244
Assignee: LAWRENCE LIVERMORE NATIONAL SECURITY, LLC
Field: Other special machines (Mechanical engineering)
Classification: CPC B  G | IPC B  G

Claim 17:
18. An in situ cure monitoring control system for use with a volumetric three dimensional (3D) printing system, wherein the volumetric 3D system includes a container defining a build volume, the container including a photocurable resist used for making a 3D part, and the resist being responsive to an optical curing beam from a light source which is controlled by a controller, and which is passed through the resist, the cure monitoring control system comprising:
an optical signal source configured to generate optical signals having a wavelength selected in relation to a characteristic of the resist, such that the optical signals experience a first level of absorption when passing through the resist when the resist is uncured, and a second level of absorption which is greater than the first level of absorption, when passing through the resist after the resist is cured, the optical signals being directed to pass through the build volume as the curing beam is also passing through the resist;
a detector for detecting the optical signals after the optical signals have passed through the resist and generating output signals in accordance therewith, the detector and the optical signal source being mounted stationary relative to the build volume; and
a monitoring module configured to communicate with the controller, and to monitor the output signals and to use the output signals to modify the curing beam to help optimize curing of the resist;
the monitoring module configured to use the output of the detector to construct a real time cure map of the resist as the 3D part is being formed;
the monitoring module further including a predetermined cure map for the resist, and configured to:
compare the real time cure map with the predetermined cure map;
to construct an error cure map from a differences between the real time cure map and the predetermined cure map; and
to use the error cure map to control the curing beam to modify curing of the resist in real time.