Device and Method for Producing a Three-Dimensional Object by Means of Mask Exposure

• US 20110101570A1
• Filed: 01/12/2011
• Published: 05/05/2011
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: Envisiontec GmbH
• Original Assignee: Envisiontec GmbH
• Inventors: Schillen, Volker, El-Siblani, Ali, John, Hendrik
• Granted Patent: US 8,815,143 B2
• Time in Patent Office: Days
• US Class Current: 264/401
• CPC Class Codes: B29C 35/0805 using electromagnetic radiation
• CPC Class Codes: B29C 35/0866 using particle radiation
• CPC Class Codes: B29C 64/124 using layers of liquid which are selectively solidified
• CPC Class Codes: B29C 64/129 characterised by the energy source therefor, e.g. by global irradiation combined with a mask
• CPC Class Codes: B29C 64/135 the energy source being concentrated, e.g. scanning lasers or focused light sources
• CPC Class Codes: B29C 71/04 by wave energy or particle radiation , e.g. for curing or vulcanising preformed articles during moulding, e.g. in a mould B29C35/08
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 50/00 Data acquisition or data processing for additive manufacturing
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes
• CPC Class Codes: G03F 7/0037 Production of three-dimensional images
• CPC Class Codes: G03F 7/2022 Multi-step exposure, e.g. hybrid; backside exposure; blanket exposure, e.g. for image reversal; edge exposure, e.g. for edge bead removal; corrective exposure
• CPC Class Codes: G03F 7/70291 Addressable masks, e.g. spatial light modulators [SLMs], digital micro-mirror devices [DMDs] or liquid crystal display [LCD] patterning devices

Abstract

The invention describes device and method for producing a three-dimensional object by solidifying a solidifiable material under an action of electromagnetic radiation by means of energy input via an imaging unit comprising a predetermined number of discrete imaging elements (pixels). The energy input related to a specific cross-sectional area of the three-dimensional object is controlled by exposure by means of multiple successive raster masks (bitmaps; e.g. bitmap 1 and bitmap 2 and possibly additional ones). The imaging unit is suitably controllable such that at least two masks can be generated, including a first overall mask covering the cross-sectional area (bitmap 1; with pixel-specific area elements exposing in white light) and a partial mask (bitmap 2; in which only a fraction of the area elements are exposed pixel-specifically with white light) within the overall mask. A voxel matrix may be formed. A hardness depth per voxel (volume pixel) can be specifically and precisely influenced in the solidifyable material.

Claims

1. A device for producing a three-dimensional object by solidifying a solidifiable object, the device comprising:

an imaging unit comprising a plurality of discrete imaging elements, wherein the imaging unit is controlled to expose a portion of a solidifiable material corresponding to a cross-section of the three-dimensional object in accordance with multiple bitmap masks, and each bitmap mask defines an energy input for each one of the discrete imaging elements.

2. The device of claim 1, wherein the multiple bitmap masks comprise a first bitmap mask and a second bitmap mask, and the second bitmap mask is a partial mask within the first bitmap mask.

3. The device of claim 1, wherein each bitmap mask includes a plurality of locations each having an associated gray value or color value that defines the energy input for a corresponding one of the discrete imaging elements.

4. The device of claim 1, wherein the cross-section of the three-dimensional object has a first region and a second region, the first region and the second region are complementary to one another, the multiple bitmap masks comprise a first bitmap mask and a second bitmap mask, the first bitmap mask defines energy inputs sufficient to solidify the solidifiable material for each of the discrete imaging elements corresponding to the first region, and the second bitmap mask defines energy inputs sufficient to solidify the solidifiable material for each of the discrete imaging elements corresponding to the second region.

5. The device of claim 1, wherein the cross-section of the three-dimensional object has a first region and a second region, the multiple bitmap masks comprise a first bitmap mask that defines energy inputs sufficient to solidify the solidifiable material for each of the discrete imaging elements corresponding to the first region and the second region and a second bitmap mask that defines energy inputs sufficient to solidify the solidifiable material for each of the discrete imaging elements corresponding to the second region but not those corresponding to the first region.

6. The device of claim 5, wherein the first region has a first cross-sectional area, the second region has a second cross-sectional area, and the second cross-sectional area is less than the first cross-sectional area.

7. The device of claim 5, wherein the multiple bitmap masks correspond to a first solidification depth for the first region and a second solidification depth for the second region, and the second solidification depth is greater than the first solidification depth.

8. The device of claim 5, wherein the second region corresponds to an object overhang.

9. A method for producing a three-dimensional object, comprising:

supplying solidification energy to a portion of a solidifiable material corresponding to a cross-section of the three-dimensional object in accordance with a first bitmap mask; and

supplying solidification energy to the portion of the solidifiable material corresponding to the cross-section of the three-dimensional object in accordance with a second bitmap mask.

10. The method of claim 9, wherein the second bitmap mask is a partial mask within the first bitmap mask.

11. The method of claim 9, wherein each of the first bitmap mask and the second bitmap mask includes a plurality of locations each having an associated gray value or color value that defines the energy input for a corresponding one of the discrete imaging elements.

12. The method of claim 9, wherein the cross-section of the three-dimensional object has a first region and a second region, the first region and the second region are complementary to one another, the first bitmap mask defines energy inputs sufficient to solidify the solidifiable material for each of the discrete imaging elements corresponding to the first region, and the second bitmap mask defines energy inputs sufficient to solidify the solidifiable material for each of the discrete imaging elements corresponding to the second region.

13. The method of claim 9, wherein the cross-section of the three-dimensional object has a first region and a second region, the first bitmap mask defines energy inputs sufficient to solidify the solidifiable material for each of the discrete imaging elements corresponding to the first region and the second region and the second bitmap defines energy inputs sufficient to solidify the solidifiable material for each of the discrete imaging elements corresponding to the second region but not those corresponding to the first region.

14. The method of claim 13, wherein the first region has a first cross-sectional area, the second region has a second cross-sectional area, and the second cross-sectional area is less than the first cross-sectional area.

15. The method of claim 13, wherein the multiple bitmap masks correspond to a first solidification depth for the first region and a second solidification depth for the second region, and the second solidification depth is greater than the first solidification depth.

16. The method of claim 13, wherein the second region corresponds to an object overhang.