Additive manufacture system using light valve device

Abstract

An object build area is exposed to a radiation beam, such as a laser light source, which has been processed and controlled through a grating light valve or valves, or planar light valve, to thereby melt, sinter, fuse or cure predetermined portions of the build area corresponding to the equivalent of individually controlled pixels, with rapid movement and positioning of the resulting LV application output array on the build area. The LV arrangement is adapted to also generally heat an entire powder bed, or targeted areas of the bed, to just below melting temperature.

What is claimed is: 
     
         1 . An apparatus for making an object in additive manufacture using an energetic source of solidifying radiation working upon a material in a build area, comprising:
 an optical element expanding a beam source into a planar beam;   at least one grating light valve (GLV) receiving the planar beam;   a beam expander for expanding a beam generated by the GLV;   a scanning device receiving the expanded beam from the beam expander and conveying the expanded beam to a build area surface;   a lens correcting the beam from the scanning device for distortion correction prior to exposing the build area;   a controller for operating the GLV and scanning device according to predetermined exposure detail constituting individual layers or slices in the build up of an object through additive manufacture.   
     
     
         2 . The apparatus of  claim 1 , wherein the controller operates the system to use the GLV for heating of the build area surface to a temperature below that of solidification of the material. 
     
     
         3 . The apparatus of  claim 2 , wherein the system is a selective laser melting system using a powder build material. 
     
     
         4 . An apparatus for making an object in additive manufacture using an energetic source of solidifying radiation working upon a material in a build area, comprising:
 an optical element expanding a beam source into a planar beam;   at least one light valve, as of a grating light valve (GLV) or planar light valve (PLV), receiving the planar beam;   a beam expander for expanding a beam generated by the LV;   a scanning device receiving the expanded beam from the beam expander and conveying the expanded beam toward a build area surface;   a lens correcting the beam from the scanning device for distortion correction prior to exposing the build area as an expanded work beam;   a controller for operating the light valve and scanning device according to predetermined exposure detail constituting individual layers or slices in the build up of an object through additive manufacture, the controller being operated in a mode whereby the expanded work beam is extended across substantially the entire build area surface in a single sweep by the scanning device.   
     
     
         5 . The apparatus of  claim 4 , wherein the controller operates the system to use the expanded work beam for heating of the build area surface to a temperature below that of solidification of the material. 
     
     
         6 . The apparatus of  claim 5 , wherein the system is a selective laser melting system using a powder build material. 
     
     
         7 . An apparatus for making an object in additive manufacture using an energetic source of solidifying radiation working upon a material in a build area having a length and a width, comprising:
 an optical element expanding a beam source into a planar beam;   at least one light valve, as of a grating light valve (GLV) or planar light valve (PLV), receiving the planar beam;   a beam expander for expanding a beam generated by the LV;   a scanning device receiving the expanded beam from the beam expander and conveying the expanded beam toward a build area surface;   a lens correcting the beam from the scanning device for distortion correction prior to exposing the build area as an elongated expanded work beam having an end to end length;   a controller for operating the light valve and scanning device according to predetermined exposure detail constituting individual layers or slices in the build up of an object through additive manufacture, the controller being operated in a mode whereby the expanded work beam is scanned along the length of the build area but its length is less than the width of the build area, the expanded work beam thereby being applied to the build area surface in passes along the length of the build area.   
     
     
         8 . The apparatus of  claim 8 , wherein the passes are adjacent one to the next and together cover the extent of the build area surface in the build up of a layer. 
     
     
         9 . The apparatus of  claim 8 , wherein the passes can be controlled to move the expanded work beam along only desired lengthwise passes and thereby covering less than the entire extent of the build area surface in the build up of a layer. 
     
     
         10 . The apparatus of  claim 8 , wherein the controller operates the expanded work beam in a raster scan mode. 
     
     
         11 . The apparatus of  claim 8 , wherein the controller operates the expanded work beam in a TV mode. 
     
     
         12 . The apparatus of  claim 8 , wherein the scanning device is an x-y scanner. 
     
     
         13 . A method for making an object in additive manufacture using an energetic source of solidifying radiation working upon a material in a build area having a length and a width, comprising:
 providing an optical element expanding a beam source into a planar beam;   providing at least one light valve, as of a grating light valve (GLV) or planar light valve (PLV), receiving the planar beam;   providing an optical system for expanding a beam generated by the LV;   providing a scanning device receiving the expanded beam from the optical system and conveying the expanded beam toward a build area surface;   correcting the beam from the scanning device for distortion correction prior to exposing the build area as an elongated expanded work beam having an end to end length;   operating the light valve and scanning device according to predetermined exposure detail constituting individual layers or slices in the build up of an object through additive manufacture, whereby the expanded work beam is scanned along the length of the build area but its length is less than the width of the build area, the expanded work beam thereby being applied to the build area surface in passes along the length of the build area.   
     
     
         14 . The method of  claim 13 , wherein the passes are adjacent one to the next and together cover the extent of the build area surface in the build up of a layer. 
     
     
         15 . The method of  claim 13 , wherein the passes can be controlled to move the expanded work beam along only desired lengthwise passes and thereby covering less than the entire extent of the build area surface in the build up of a layer. 
     
     
         16 . The method of  claim 13 , wherein the controller operates the expanded work beam in a raster scan mode. 
     
     
         17 . The method of  claim 13 , wherein the controller operates the expanded work beam in a TV mode.