Hermary scanners and many industrial 3D scanners work on the principle of laser triangulation. A laser beam is projected at a known angle onto a target to be measured; a camera at a known offset from the laser views the projected image.
Principles of Laser Triangulation
Understanding the laser scanning process can help you choose the right industrial 3D scanners for the job. The principles of triangulation gather data points in a reference plane established by a laser fan beam. All data points will be somewhere on this plane. If the laser strikes an object at A, this will be seen by the scanner’s image sensor at location A’. If the laser strikes an object at position B, it will be seen at B’. By examining where the laser is seen by the sensor, the scanner can calculate the distance to the object. 
A Typical 3D Scanner Setup
The setup below is a typical industrial setting. There are many 3D scanners that combine both the illumination source and the imaging sensor in one housing.
A typical laser triangulation setup
3D Scanner Working Principles and How Point Cloud Works
3D machine vision, more broadly known as 3D scanning technologies, empowers inspection, feature identification, object detection, and process optimization by taking three-dimensional measurements of a target object. The most widely used 3D scanning technology is powered by the principle of laser triangulation.
3D data is often captured in coordinates, namely, X, Y, and Z. These coordinates collectively form point clouds that represent the 3D shape of the object being scanned. Depending on the scanner position and arrangement, further data manipulation may be required.
3D Scanners Using Geometric Measurement Techniques
This video shows how laser scanners work seamlessly to capture a target object’s dimensions using the principle of triangulation. In modern manufacturing, laser triangulation is one of the most robust and reliable industrial scanning methods.
