Topography with Laser Line

In the previous lessons, we considered images acquired by a regular camera, meaning we had no direct information about the 3D shape of the inspected objects.

In many inspection scenarios, we need to obtain the object’s topography. We might want to measure its volume or check for bumps and holes. Some options for acquiring topography information include:

• Stereoscopic vision system: Multiple cameras grab images of the same scene. When properly calibrated, a stereoscopic vision system can reconstruct the 3D coordinates of matched points. It will typically produce a sparse point cloud.

• Time-of-flight cameras: A projector sends light pulses on the scene, and a camera detects the pulse’s reflections. The delay between the pulse emission and its detection allows us to evaluate a dense topography map. Such a system can be a viable option when a spatial ...