How 3D Structured-Light Scanners Work & How We Save You Time & Money

The basic function of a structured-light scanner is straightforward. The scanner’s lightsource projects a pattern of light from a 2D lens onto a 3D object, which distorts as it interacts with the object’s surface. It is also possible to use two laser beam points to intersect.

The distortion that occurs is filmed using multiple, sophisticated cameras, capturing even the slightest displacement in light. The scanned distortions are directly converted into 3D coordinates. These coordinates are used to generate a model of that particular area on the object’s surface. The object is then rotated, repeating the process, and the scanner records the next visible section of the object.

Once the entire object is scanned, the data is processed by scanning software, using a method of triangulation in which the depth and surface information of the object is determined. The multiple scans are then cleaned up and stitched together, forming a highly-detailed, digitized three-dimensional model. This last step in the scanning process is referred to as post-processing. Both white and blue light scanners use the same technology, but the type of illumination differs.

White light scanners perform surface height measurements of an object using white light as a source of illumination. These devices can be used on a camera mount, tripod, or robot to create a point-and-shoot style workflow that minimizes any set-up or programming time.

White light scanning is the predecessor to blue light scanning, and is typically more accessible than blue light, however, blue light scanning results has proven to be more accurate and less susceptible to the effects of transparency or reflections.

Structured-light scanning systems that operate using LED bulbs, or blue light, are referred to as blue light scanners.

These are considered to be more accurate than white light scanners, and provide an enhanced experience compared to white light scanning. The two types of light are used in similar situations; however, blue light offers a higher output of quality through increased precision and accuracy.

Blue light scanners yield better results due to the fact that LED has a narrower wavelength, whereas white light is a combination of all the colors on the visible spectrum. Blue light is able to filter any interference from ambient light much more effectively than white light is. It is safe to say that blue light scanners offer enhanced capabilities, however, white light scanners are also capable of highly-accurate measurements.

Structured-light scanning systems provide ease of use, accuracy, and a number of advantages compared to other traditional methods of 3D scanning. Some applications of structured light 3D scanning include:

• Dimensional measurements used for the reproduction of parts, defect detection, repairs, and further quality assurance.
• Reverse engineering (RE) of objects, used to produce CAD data in particular.
• Automated optical inspection in high-volume manufacturing and assembly.
• Volume measurement of complex, engineered parts.
• Recovery of damaged or worn parts.