For laser marking applications, there is often a need to change the spot size and focus height during the mark to achieve the shade, surface finish and speed of the mark. Using a small laser spot gives good image quality in the edges and corners of the mark, but large areas of filling in the image can take a long time to complete. A small spot will etch into a metal part creating a bright, textured mark. A larger spot on the other hand is useful for filling large areas of a laser marked image, but leads to a low definition of the edges of the image. Larger spot sizes will have an annealing effect, creating a smooth, dark mark.
For many applications, the benefits of both a small and large spot size may be required on the same part. Changing the spot size by ‘de-focussing’ the laser leads to inconsistencies in the marking process. The part may have different levels, requiring the focus height to be changed during the mark.
Using the new Zoom Beam Expander from Laser Components, both the laser spot size and focus height can be adjusted in real time. Unlike commonly available manual beam expanders, the Laser Components beam expander can be integrated into a production process, with compatible lasers from IPG, Raycus, SPI Ø35 collimated and SPI LPPK diverging output housings.
A number of standard beam diameter ranges are available, with multiple control options to suit most laser marking applications. Custom configurations are available upon request.