Apparatus for additively manufacturing of three-dimensional objects
Apparatus ( 1 ) for additively manufacturing of three-dimensional objects ( 2 ) by means of successive layerwise selective irradiation and consolidation of layers of a build material ( 3 ) which can be consolidated by means of an energy beam ( 4 ), wherein a measuring unit ( 5 ) is provided that is configured to generate information relating to a collimated part ( 6 ) of the energy beam ( 4 ) and information relating to a focused part ( 7 ) of the energy beam ( 4 ).
1. Apparatus for additively manufacturing of three-dimensional objects by means of successive layerwise selective irradiation and consolidation of layers of a build material which is consolidated by means of an energy beam, characterized by a measuring unit comprising:
a first beam splitter located between a collimating optic and a focusing optic;
a first measuring device is configured to generate information relating to a collimated part of the energy beam;
a protective glass arranged between the focusing optic and a build plane, wherein the protective glass is configured to reflect at least a part of a focused part of the energy beam before contacting the build plane; and
a second measuring device configured to generate information relating to the focused part of the energy beam reflected from the protective glass.
2. Apparatus according to claim 1 , wherein a first optical beam path extends from the collimating optic through the focusing optic onto the build plane and a second optical beam path extends from the collimating optic to the first measuring device and a third optical beam path extends from protective glass through the focusing optic to the second measuring device, wherein the first measuring device is configured to generate information relating to a current focal length of the collimating optic, and wherein the second measuring device is configured to generate information relating to a current focal position of the focusing optic and/or an optical parameter of the focusing optic.
3. Apparatus according to claim 2 , characterized in that the first measuring device comprises a second beam splitter configured to split a second energy beam travelling the second optical beam path into two sub-parts and/or the second measuring device comprises a second beam splitter configured to split the part of the energy beam travelling the third optical beam path into two sub-parts.
4. Apparatus according to claim 3 , characterized in that the first measuring device and/or the second measuring device comprise two optical sensors, wherein the first sub-part is measured via the first optical sensor and the second sub-part is measured via the second optical sensor.
5. Apparatus according to claim 4 , characterized in that at least two optical sensors of the same measuring device are arranged in different distances and/or movable relative to the second beam splitter.
6. Apparatus according to claim 2 , characterized in that the second measuring device comprises a dichroic beam splitter configured to split radiation traveling the third optical beam path into a first sub-path extending from a zone of the build plane to a meltpool monitoring unit and a second sub-path reflected from a surface between the focusing optic and the build plane to the second beam splitter of the second measuring device.
7. Apparatus according to claim 1 , characterized in that the information generated by the first measuring device comprises or relates to:
a current beam power and/or
a current focal length of the collimating optic.
8. Apparatus according to claim 1 , characterized in that the information generated by the second measuring device comprises or relates to:
a current focal position and/or,
an optical parameter of the focusing optic.
9. Apparatus according to claim 1 , characterized by an optical diaphragm located in a focal position of the energy beam reflected by the protective glass.
10. Apparatus according to claim 1 , characterized in that at least one information generated by the measuring unit is transferable to a quality management system.
11. Apparatus according to claim 1 , characterized by a control unit configured to control at least one process parameter of the energy beam dependent on at least one information generated by the measuring unit.