Three dimensional printing adhesion reduction using photoinhibition

Abstract

Methods, systems, and apparatus, including medium-encoded computer program products, for three dimensional print adhesion reduction using photoinhibition include, in one aspect, a method including: moving a build plate in a vat of liquid including a photoactive resin; creating a photoinhibition layer within the liquid directly adjacent a window of the vat by directing a first light through the window into the liquid, the first light having a first wavelength selected to produce photoinhibition; and creating a solid structure on the build plate from the photoactive resin within a photoinitiation layer of the liquid by directing a second light through the window into the liquid, where the photoinitiation layer resides between the photoinhibition layer and the build plate, and the second light has a second wavelength different than the first wavelength.

What is claimed: 
     
         1 . A method for printing a three dimensional (3D) object, comprising:
 (a) providing (i) a build platform adjacent to a window, and (ii) a resin between said build platform and said window;   (b) directing a first light and a second light through said window to said resin, wherein (i) said first light subjects a first portion of said resin to curing to yield a polymeric layer coupled to said build platform or a previously deposited layer, and (ii) said second light inhibits curing of a second portion of said resin;   (c) using one or more sensors to detect said polymeric layer; and   (d) modifying an operation of said printing based at least in part on said polymeric layer detected in (c).   
     
     
         2 . The method of  claim 1 , further comprising using said one or more sensors to detect curing of said first portion of said resin into said polymeric layer. 
     
     
         3 . The method of  claim 1 , further comprising processing said polymeric layer detected in (c) and a pattern of said first light directed through said window resin to determine whether said 3D printing is proceeding correctly. 
     
     
         4 . The method of  claim 1 , wherein said one or more sensors comprise a camera. 
     
     
         5 . The method of  claim 1 , wherein said modifying comprises adjusting an intensity or exposure time of said first light or second light. 
     
     
         6 . The method of  claim 1 , wherein said modifying comprises adjusting an amount of said resin. 
     
     
         7 . The method of  claim 1 , wherein said modifying comprises (i) supplying said resin comprising a photon absorbing species to a region adjacent to said window through an inlet in fluid communication with said window, or (ii) removing said resin comprising said photon absorbing species from said region adjacent to said window through an outlet in fluid communication with said window, thereby adjusting an amount of said photon absorbing species in said resin. 
     
     
         8 . The method of  claim 1 , wherein (c) is performed prior to printing an additional layer of said 3D object. 
     
     
         9 . The method of  claim 1 , further comprising detecting adhesion of said polymeric layer to said window. 
     
     
         10 . The method of  claim 1 , further comprising, during said printing, increasing a distance between said build platform and said window along a direction away from said window. 
     
     
         11 . The method of  claim 10 , wherein said distance is increased by moving said build platform along said direction. 
     
     
         12 . The method of  claim 1 , wherein during at least a portion of said printing, said build platform is not in contact with said resin. 
     
     
         13 . The method of  claim 1 , wherein said first light and said second light are generated by different light sources. 
     
     
         14 . The method of  claim 1 , further comprising iteratively directing a varying pattern of said first light through said window and increasing a distance between said build platform and said window. 
     
     
         15 . A system for printing a three dimensional (3D) object, comprising:
 a window configured to retain a resin;   a build platform configured to support a polymeric layer generated from said resin during said printing;   one or more light sources configured to direct a first light and a second light through said window to said resin;   one or more sensors configured to detect said polymeric layer; and   a controller operatively coupled to said one or more light sources and said one or more sensors, wherein said controller is configured to:
 (i) direct said one or more light sources to direct said first light and said second light through said window to said resin, wherein (1) said first light subjects a first portion of said resin to curing to yield said polymeric layer coupled to said build platform or a previously deposited layer, and (2) said second light inhibits curing of a second portion of said resin; 
 (ii) use said one or more sensors to detect said polymer layer; and 
 (iii) modify an operation of said printing based at least in part on said polymeric layer detected by said one or more sensors. 
   
     
     
         16 . The system of  claim 15 , wherein said controller is configured to process said polymeric layer detected by said one or more sensors and a pattern of said first light directed through said window to determine whether said 3D printing is proceeding correctly. 
     
     
         17 . The system of  claim 15 , wherein said one or more sensors comprise a camera. 
     
     
         18 . The system of  claim 15 , wherein said controller is configured to adjust an intensity or exposure time of said first light or second light. 
     
     
         19 . The system of  claim 15 , wherein said controller is configured to adjust an amount of said resin. 
     
     
         20 . The system of  claim 16 , wherein said one or more light sources comprise different light sources configured to generate said first light and said second light.