Tomographic Additive Manufacturing Spatial Coherence
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Tomographic additive manufacturing faces challenges in achieving accurate and high-resolution prints due to the solidification of photosensitive material in unintended areas, caused by the light beam traversing the entire build volume, leading to inaccuracies and artefacts in the printed objects.
Innovation Solution
The use of a spatially coherent light source with a low étendue and beam-parameter product, such as lasers or multiple lasers coupled into an optical fiber, ensures precise light distribution and minimizes unwanted solidification, allowing for accurate and high-resolution three-dimensional object creation by controlling the light dose distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a light beam traverses the entire build volume in tomographic additive manufacturing, then the photosensitive material can be illuminated from multiple angles for volumetric printing, but unwanted parts of the build volume accidentally become solidified leading to inaccuracies and artefacts
Solution Approach 1:
The patent applies local quality by using spatially coherent light sources (lasers) that can be precisely directed to illuminate only specific local regions of the photosensitive material. This allows the light to affect only the intended voxel locations rather than the entire build volume, thereby achieving both volumetric printing capability and high print accuracy by making the illumination effect localized to where it is needed.
2Device complexity
If conventional light sources are used in tomographic additive manufacturing, then the system is simpler and more versatile, but the spatial coherence is insufficient leading to poor print accuracy and resolution
Solution Approach 1:
The patent applies parameter changes by selecting light sources with specific optical parameters - specifically spatially coherent light sources like lasers that have high spatial coherence and low étendue. This parameter change in the light source properties enables precise control over light propagation and focusing, achieving high print resolution while managing system complexity through the use of established laser technology.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances print accuracy and resolution by maintaining a well-defined spatial dose distribution throughout the build volume, reducing artefacts and improving the depth of field, thereby achieving higher quality and more precise three-dimensional objects.
Implementation Method 1
A build volume containing a photosensitive material is then illuminated from many angles with these computed patterns of light, which leads to the solidification of well-defined parts of the photosensitive material into the final object
Data Source
AI summary
A method of fabricating a three-dimensional article comprises providing a spatially coherent light source (101, 201), generating from the light source (101, 201), patterns of light based on computed tomographic projections of the three-dimensional article, and projecting the patterns of light into a photoresponsive medium. The projecting is configured to define a three-dimensional dose distribution, thereby locally altering the phase of the photoresponsive medium and creating the article.