An essential basis for reliable and targeted process control is understanding the interaction between the laser beam and the material to be processed. There are various sensor principles that can be used for in-situ detection of the machining process when machining with short and ultrashort laser pulses, including short coherence interferometry (OCT).

Since most applications with short or ultrashort pulsed lasers are a combination with a scanning technology to deflect the laser beam, the selected sensor technology must be adapted to these specific processing heads. This article deals with applications where it is necessary to measure the ablation depth in-situ in order to control the process. Processes where it is necessary to quantify the cleaning process and its results. With a high measuring frequency of the sensor device, it is possible to achieve this goal. And in the case of sensor principles with their own light source, the induced chromatic shift caused by the F-theta lens of the scanner device can be reduced by clever selection of the wavelength.

This contribution to ICALEO 2025 will present initial results in the investigation of possibilities for capturing process results when processing surfaces with short laser pulses and we will discuss these results.