Laser Marking
The use of lasers for industrial marking and materials processing has seen rapid growth in recent years. Here, a high-intensity laser is used to melt, etch, sinter, ablate, or in other way modify the exposed material relative to its surrounding. Until now, the dominant approach in this application has been a single beam rastered over the work surface by galvo scan mirrors. While the focused beam is effective in generating the intensity needed to modify the material, the throughput of such systems is limited as the area is written sequentially using just a single beam. Recent advances in total available laser power are enabling higher productivity alternatives. For example, by replacing the scan mirror with a spatial light modulator, the single beam is turned into hundreds or thousands of beamlets all writing to the surface in parallel. Clearly, this throughput boost requires a spatial light modulator with outstanding power-handling capability. The robust materials-set comprising the GLV position it well to serve this emerging application.
Examples of Written Media
We have created a laser marking system to demonstrate the benefits of using the PLV. This system uses a 1064nm, 10ps, 20W laser to illuminate the PLV. The PLV is then imaged with a demagnification of 10x to give high fluence with 20um resolution at the work surface. This system was designed for making black marks on stainless steel, but has also been used on aluminum, plastic, and graphite.
See how PLV can be used for Laser Marking.
The figure above shows various patterns marked on 304 stainless steel with a brushed finish. The line beam is ~1mm long and scanned along the long dimension of each image. The features are well-defined with sharp edges and text is crisp and easy to read.
While the system was optimized for stainless steel, it can be used on other materials as well. Figure above shows high-resolution images on aluminum
Images marked on generic white plastic index card using 515nm femtosecond laser