Surface inspection in industrially produced “high-quality” products plays an increasing role in the industry.

The outer appearance of products is an important purchasing criterion for the customer. If a product has any surface defects, such as pits, dents, blisters, paint defects, etc., the customers’ purchasing interest drops due to the bad processing quality.

In order to efficiently produce a product at consistent quality, surface inspections must be performed at high-contrast lighting during early stages of the production process already, since it is often the case that few or no surfacve defects can be perceived under low-contrast lighting, which would cause them to enter the further production processes.

The surface control optics developed by us permit improved control of the surfaces. A special lighting simplifies the conditions for visual surface inspection and permits initiation of process corrections in a timely and effective manner.

Depending on the type of surface and type of defect there are different surface control optics:

• Surface control optics for surfaces with high reflectance
• Surface control optics for surfaces with low reflectance

Areas of use

Painted surfaces with usually smooth surfaces have a very high reflection level. In contrast to matte surfaces, smooth surfaces emit a much higher luminance. Glare develops very quickly.
This circumstance of glare is highly unsuitable for optimal surface inspection. In order to reduce glare, and thus the emitted luminance, lighting intensity must be reduced or adjusted to the surface brightness.

Contrast vision can be improved with surface control optics here as well. However, these special lamps show broader black fields and produce a rougher freflection image on the surface.
Other special surface control optics bring out even polishing defcts on the surface.

Areas of use

Continuous quality control along the production chain is broken down into many partial steps with many different requirements. For example, the reflection levels between the parts to be inspected differ. A raw part from the press has entirely different reflection properties than a finally painted part and accordingly requires a different lighting.

Untreated raw parts usually have a mattle surface. The reflection level of such surfaces is accordingly very low at 0.1 to 0.2 p. The emitted luminance is not sufficient for the human eye to easily recognise errors. A visual inspection is only possible with difficulty.

In order to permit an optimal surface inspection, the luminance on the surface must be increased based on lighting intensity. Surface control optics with narrow black fields project a fine reflection image onto the surface and thus support contrast vision. Even small surface defects can be perceived more easily.