## 1 Introduction
### Laser Profilometry (LPM)  
Laser profilometry plays an important role in the evaluation of surface roughness parameters. It is capable of accurately and reliably measuring the dimensional accuracy, the shape accuracy, and the surface roughness of components. Laser profilometry makes it possible to obtain detailed information about surface deviations, curvatures, the thickness of coatings, geometric shapes, and other critical parameters that are important for the functional reliability and service life of components [20]. Laser profilometry, applying the triangulation principle, involves projecting a linear laser beam onto the surface of the object being measured at a specific angle. Subsequently, a camera positioned perpendicular to the object's surface detects the deformed image (profile) of the laser's track on the surface (Figure 1). After that, the surface of the object to be measured, or the sensing device itself, is moved by a small distance with the help of a programmable displacement, and another profile is captured by the camera. This procedure is repeated, obtaining a series of profiles from the surface of the measured object. After obtaining several profiles, their images are combined and aligned into one overall image, resulting in an actual 3D profile of the measured object, which provides a large amount of information about the surface structure, such as differences in height, the roughness, geometric characteristics, and other parameters. This information is important in assessing the quality of the surface and its functional properties, as well as in identifying possible problems or changes during operation. This process of the composition and subsequent evaluation of individual profiles is implemented using specialized software equipment for laser profilometry itself [21]. In the past, laser profilometers and scanning technologies used (red) lasers with a wavelength of around 650 nm, or infrared lasers. This color of light was common for historical reasons and was considered suitable for the given applications [22]. In recent decades, the rapid development of microelectronics and material physics has resulted in a wide spectrum of light sources being available for experimental 3D measurement setups [23]. Traditional lasers are gradually being replaced by laser diodes, which provide a sufficient coherence length necessary for use in coherent topographic methods and are also more affordable [24]. Currently, however, with the expansion of modern technologies and their implementation in various areas, alternative laser devices with different wavelengths of radiation than the red spectrum are beginning to appear. The reason is the need to look for new possibilities and to adapt to specific requirements and properties of materials and applications [25]. There are several reasons why alternative colors of laser light are being explored. For example, some materials may have better visibility or contrast with other colors of light, which can lead to more accurate and reliable roughness measurements. The use of other wavelengths may bring advantages for certain applications, such as improved resolution when measuring finer structures or a better ability to penetrate the surface [26]. Laser profilometry is widely used in all branches of industry, where quality control of the surface properties and the shape of objects is important. This technology enables fast and accurate measurements in real-time, which contribute to the higher quality, efficiency, and productivity of production processes [27]. Introducing the spatial control of surface quality into metrological practice is a challenge that requires us to solve technical, economic, and processing problems. Not only the surface measurement itself but also the processing of the results and the effective use of the obtained information are important aspects. The effective use of this method will depend on the ability to solve these challenges and provide relevant and reliable surface information for various applications in industry and metrology [28].