One of the most common types of non-contact 3D scanning is structured light scanning. Used for both dimensional inspection and reverse engineering, structured light scanning employs projected light and cameras to measure the three-dimensional surfaces of an object.
How Structured Light Scanning Works
The most basic principle behind structured light 3D scanning is triangulation. Light is projected in a pattern (usually a series of parallel lines) that becomes distorted on the surface of the object. Cameras capture this distortion from multiple angles, triangulation calculates the distance to specific points on the object, and the three-dimensional coordinates are used to digitally reconstruct the object in great detail.
The types of light used in structured light scanning include both white light and blue light. Although both options are effective in terms of accuracy and speed, blue light offers some benefits over white light in certain situations because it typically has:
- More portable equipment
- An LED light source that lasts longer
- A cooler operating temperature than white light
- Higher tolerance for scanning in a room with other light sources
Regardless of whether you use white light or blue light, the concepts behind the technology remain the same: A light pattern is projected onto an object, and cameras measure the distortions caused by the surface details of the object.
When to Use Structured Light Scanning
You might use this technique when contact scanners are not appropriate. For example, if the object is elastic, delicate, or otherwise difficult to handle, structured light scanning can be used without impacting the surface of the object.
Because they project many points of light at the same time, structured light scanners operate with great speed and precision relative to some other scanning methods. This efficiency is one of the reasons that this type of scanning is becoming more commonplace. Structured light scanning can also be used from the micro scale all the way to large objects such as airplanes, thus making it one of the more versatile 3D scanning technologies available.
The type of structured light scanning you should use will depend on other surface characteristics such as reflectivity, transparency, and roughness. In some cases, structured light scanning is not an appropriate method because diffraction and reflection can affect the measurements. The best way to decide which type of scanning makes the most sense for your application is to work with a qualified 3D scanning provider that has extensive experience with multiple scanning techniques.
If you are interested in learning more about structured light scanning and other 3D scanning techniques for a practical application, contact the experts at Q-PLUS Labs. We'll work closely with you to determine the type of scanning that makes the most sense for your application so you can get useful results within your budget. Contact us today to schedule a consultation.
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