SLE (selective laser-induced etching) is a new laser technology for rapid manufacturing of true 3D devices made out of transparent material consisting of cavities, tunnels and even mounted moving parts.
SLE is a two-step process: In a first step ultra-short pulsed laser radia-tion is focused to micrometer-sized focus to permanently modify the transparent material internally. This laser modification is done without cracks and with high precision ¡ª not to be confused with the 3D pictures in glass consisting of micro cracks. An arbitrary 3D connected volume is exposed inside the glass by 3D scan-ning of the focus. In a second step of developing only the modified mate-rial is removed by wet chemical et-ching starting at a surface of the workpiece.
For the precision of the SLE tech-nique the selectivity is essential. The selectivity is the ratio of the etching rate of the modified material and the etching rate of the untreated ma-terial. For example the selectivity in fused silica glass is larger than 500:1 resulting in long fine channels with small conicity. Therefore, by the SLE- technique complex 3D cavities can be produced, which are the basis of our products like micro fluidic struc-tures and micro structured 3D parts.
Advantages of SLE are the large preci-sion (¡ª 1pm), no debris, true 3D capa-bility and the high processing speed using our LightFab 3D Printer. There-fore, the SLE technology is perfect for digital 3D printing of components made out of transparent material.
Present state of the art for our reali-zation of the SLE process chain in-cludes the straightforward laser tool path generation from 2D & 3D-CAD models in a wide variety of common file formats. That way design changes can be easily implemented and tes-ted e.g. for rapid prototyping. After identification of an adequate proto-type for your special application even series production can be performed with the same system due to speed of the LightFab 3D Printer unrivaled at the market. For mass production of single designs the production can be transferred to our High Speed Mi-croscanner which has to be custo-mized for the special design.
