# Modelling the Interaction of Illuminations with a Sensor Matrix Used in Vision Systems
## 1 Introduction  
The development of lighting techniques can be dated as early as 300,000 years ago, at the time of the discovery of fire by prehistoric people, who served as a source of heat and light. Bonfires, torches, the first tallow, and oil lamps made it possible to live in caves and create the first wall paintings, i.e., the first paintings. The first drawings painted in caves had to be made using artificial lighting. The development of lighting technology made it possible to build the first lighthouses and lamps installed on the streets. A wide range of light sources with different spectral characteristics and purposes is available. The selection of illuminators for a specific control or measurement task is carried out based on the analysis of the spectral characteristics of the illuminator and the study of its operating parameters. Vision systems used in industrial applications use various types of illuminators selected for specific control or measurement tasks [1; 2]. The basis of imaging is the registration of electromagnetic radiation in a selected spectral range on the sensor matrix. On this basis, a description of the scene in the form of a picture is created. The illuminator's design and its operation's spectral range have the most significant impact on the parameters of the recorded image [3; 4]. However, it is also necessary to take into account the way the lighting interacts with the surface of the imaged object. The spectral range of electromagnetic radiation reaching the sensors built on the matrix from the illuminator is also influenced by the parameters of the lens. Equally important are the filters placed on the lens and filters applied directly to the sensor matrix. Significant disturbances in industrial conditions are introduced by unstable lighting of production halls and changes in solar lighting reachingthe production stations. In addition, in the optical path between the illuminator, the illuminated object, and the sensor matrix, interference in the form of water vapour or vapours of various chemical compounds may occur in industrial conditions. Measurements with vision systems carried out in laboratory conditions eliminate most disturbances [5]. However, in industrial settings, the interaction of lighting with the geometric structure of the surface is of great importance in surface imaging tasks. It has been shown that in industrial conditions, there is not only one type of interaction [6]. The most common combination of interactions between a light and a surface depends on the surface condition, which changes the radiation image recorded on the sensor matrix. For example, measurements of the parameters of the geometrical structure of the surface in terms of surface defects and surface roughness require an individual approach, which must consider the type of material and the conditions for the measurement. For example, measurements of the parameters of materials produced by selective laser sintering required the selection of the kind of lighting and a specialized optical path for the imaging method [7]. The choice of the type of illuminator is a crucial task from the point of view of industrial imaging. It is the task of the illuminator to indicate and strengthen the feature of the examined object in such a way that it is visible in the recorded image. The selection of the light source, the choice of the illuminator structure, the selection of the frequency of the illuminator, and the selection of the spectral range of the illuminator's operation determine the success of the imaging process. The quality of the recorded image determines the possibility of using it in measurement and control tasks. It should be noted, however, that the illuminator parameters must be selected for a specific measurement task, taking into account the specific operating parameters of the vision system. The selection of industrial lighting should also consider the change in the working conditions of operators working on the production line.