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照明的使用应尽可能使要检查的地物与周围环境形成最佳对比。照明的颜色、照明的角度和照明的形式对图像中特征的可见度有很大影响。
信息：
良好的照明是获得良好图像的基本条件，因此也是获得良好测量结果的基本条件！
无论是在自然界，还是在建筑物和工业厂房中，光线通常都是不受控的。它具有以下特点：
•光照强度变化：这可能是由一天中的时间、天气条件、移动物体投射的阴影、建筑物照明的外来光线等造成的。
•色谱变化：这受一天中的时间、具有滤光效果的窗户、使用具有不同发射光谱的灯具的人工照明等因素的影响。
•偏振：随太阳位置和周围环境而变化。
•改良照明技术并非为图像采集而设计。
这就是为什么不受控制的光线会给机器视觉带来特别的问题。不过，在仪器设备中应用工业机器视觉时，光线应该是可控的。
通过选择合适的照明技术、灯具、较高的光强度、滤光片等，可以创造出适合采集的条件，以特别突出物体的特性。通过滤光技术对摄影材料进行后续处理，确实可以弥补一些照明误差，但所获得结果的质量始终会受到影响。
要检查的物体特性在很大程度上决定了照明的选择。
Lighting should be used to create the best possible contrast between the features to be examined and the immediate surroundings. The colors of the lighting, the lighting angle and the lighting form have an enormous effect on how features are visible in the image.
Information:
Good lighting is an essential requirement for good image acquisition and thus for a good measurement result!
In nature, but also in buildings and industrial plants, light is usually uncontrolled. It has the following characteristics:
•Varying light intensity: This can be caused by the time of day, weather conditions, shadows cast by moving objects, extraneous light from a building's lighting, etc.
•Varying color spectrum: This is affected by the time of day, windows that have a filter effect, artificial lighting using lamps with varying emission spectra, etc.
•Polarization: Varies according to sun position and surroundings.
•Improvised lighting technology not designed for image acquisition.
This is why uncontrolled light poses a particular problem for machine vision. However, when applying industrial machine vision in the context of instrumentation, the light should be controlled.
By choosing suitable lighting technologies, lamps, higher light intensities, filters and so on, it is possible to create conditions for acquisition that are suitable for highlighting the object properties particularly well. Subsequent processing of the photographic material by means of filtering techniques can indeed compensate for some lighting errors, however, the quality of the achievable results always suffers.
The object properties to be examined largely determine the choice of lighting.