LIGHTING SCHEMES

Lighting principles and typical applications for choosing the CIS setup.

In dark field illumination, the light strikes the material from the side at an inclined angle. This configuration is suitable for low-reflectance objects and helps highlight surface details, defects, or contamination that may be less visible with more frontal lighting. With external sources, the illumination angle can be adjusted depending on the object being inspected.

This configuration uses specular reflection: light strikes the surface at a defined angle and is collected at the same angle of reflection. It is suitable for inspecting flat, glossy surfaces and helps highlight contrast differences due to scratches, bumps, depressions, and other surface defects.

In coaxial reflection, the light illuminates the sample vertically, and the reflected signal returns to the sensor along the same optical axis. This configuration is suitable for brushed metal surfaces and, more generally, for reflective materials where a more stable reading of surface details is required.

Thanks to the coaxial configuration, the system helps reduce irregular reflections from shiny surfaces and overcome problems related to the directionality of brushing on metal, improving image readability in the most critical applications.

In backlighting, the light passes through the material being inspected and the CIS detects the object’s profile in transmission. This configuration is suitable for shape checks, profile measurements, PCB contour inspection, and through-hole measurement, where a clear reading of edges and geometries is required.

LED illumination integrated directly into the CIS, designed to ensure stable and repeatable light across the entire scan width.

Ideal for opaque or diffusely reflective materials and for standard imaging and inspection applications where compactness, simple integration and consistent acquisition are required.

The illumination angle is fixed, as defined by the CIS design.