The Fraunhofer Institute for Laser Technology ILT is developing solutions for the production of optics using new laser processes. These make it possible to produce components with minimal roughness and high functionality - from microlens arrays to free-form optics. "With our laser processes, we bring optics directly into shape - without detours, without reclamping, quickly and cost-effectively," says Dr. Edgar Willenborg, who helped establish the topic of optics production at Fraunhofer ILT. The researchers achieve a high level of efficiency, particularly with more complex geometries.
Machining lenses in a single clamping operation
A key process is selective laser-induced etching (SLE), which is used to process the front, back and edges of lenses in a single clamping operation. This method reduces production times and costs. Another technique, laser ablation, makes it possible to create complex shapes from inexpensive glass bodies - such as aspheres or free-form optics that are used in cameras or sensors.
Finishing with laser technology
Shaping is followed by finishing: lasers polish surfaces that are still rough due to previous processing. The laser heats the surface so sensitively that the smallest unevennesses melt away within a few seconds and without mechanical contact. Willenborg and his team are researching laser beam figuring (LBF) for particularly high demands on shape accuracy. This involves the targeted removal and correction of the smallest form deviations in nanometer layers, which is crucial for high-performance optics, for example.
New processes for the assembly of optical systems
In addition to shaping and polishing, the Fraunhofer ILT is also developing processes for the assembly of optical systems. These include the precise bonding or soldering of components so that they remain stable even under load. "Our processes are particularly in demand when conventional manufacturing methods reach their limits," says Dr. Willenborg. Complex geometries and materials that are difficult or expensive to process using traditional methods can be realized efficiently and cost-effectively using laser technologies.