Software By bitgraphicXTable of Contents
Whether you’re reverse engineering existing parts, verifying fit within an assembly, or simply digitizing a physical object, choosing the right 3D scanning tool is crucial. In this guide, we’ll explore the core technologies, key differences, and important specifications to help you select the best 3D scanner for your needs.
How does 3D scanning work?
Laser vs. Structured Light Scanners, what’s the difference?
Desktop or handheld scanners, which one should you choose?
Topics we will cover in second article
Key specifications to consider when selecting a 3D scanner
Common applications of 3D scanning
How do 3D scanners work?
3D scanners are optical measurement systems that capture data from physical objects, environments, or subjects and convert it into an accurate digital representation.
The information captured includes an object’s geometry, surface characteristics, texture, and spatial position within a defined field of view. This data is processed into a 3D point cloud, which is then converted into a closed mesh or solid model. These digital models can be imported into CAD, inspection, or 3D modeling software for analysis, modification, and manufacturing workflows.
3D scanning often replaces traditional measurement methods such as manual measuring, mold-making, or plaster casting, reducing time while improving accuracy and repeatability.
Among the many scanning technologies available, laser triangulation and structured light projection are the most widely used due to their versatility across industries. Both technologies project light onto an object and use cameras to capture how that light interacts with the surface. Through triangulation, the captured points are calculated in 3D space and merged into a complete mesh model.
These systems determine distance by analyzing how light is reflected, distorted, or deformed by the object’s surface.
What are the differences between Laser and Structured Light scanners?
Laser scanning is generally less sensitive to ambient lighting and works better on dark or reflective surfaces. It projects one or more laser lines onto an object, creating precise rows of data points where the laser contacts the surface. While extremely high in resolution, scanning a single line would be inefficient, so most laser scanners are handheld and use multiple laser lines to cover large areas efficiently, such as automotive bodies, aircraft components, boats, and ships.
Laser scanners rely on reflective markers placed on or around the object to align scan data accurately. Due to their precision, they are widely used in metrology applications, with some systems achieving point spacing as fine as 0.05 mm and volumetric accuracy of 0.05 mm/m. High-performance systems typically cost between $20,000 and $60,000.
Structured light scanners, on the other hand, project patterned light — such as stripes or grids, onto an object’s surface. One or more cameras track how these patterns deform, allowing the system to capture large areas quickly with strong accuracy and resolution, though slightly lower than laser scanning.
A major advantage of structured light is flexibility in alignment. Data can be aligned using surface features, markers, or color information, whereas laser scanning primarily depends on markers. With the addition of color cameras, structured light systems can capture full 24-bit color, making them ideal for artwork, organic shapes, and surfaces with distinct color variation.
Structured light scanners often use infrared, white, or blue LED light sources, which are safe for human eyes and suitable for scanning faces and people. They work well as stationary or handheld systems but are more sensitive to ambient lighting and can struggle with very dark or highly reflective surfaces.
Desktop vs. Handheld Scanners, which should you choose?
Desktop scanners usually project multiple light patterns onto a stationary object, often placed on a turntable, capturing a series of images to build a 3D model. Handheld scanners capture data continuously as the operator moves around the object, allowing for rapid coverage from multiple angles.
Why choose a desktop scanner?
Best for capturing small parts (around 0.5 to 2 inches) with very high resolution and accuracy.
Turntable-based scanning is simple and repeatable.
Shadowing may occur, requiring multiple orientations to capture all surfaces.
Desktop systems often use structured light technology and can outperform handheld structured light scanners in resolution and precision.
Why choose a handheld scanner?
Ideal for large or complex parts, capturing wide surfaces efficiently.
Many handheld systems capture 500,000+ points per second at 15+ frames per second.
Portable, versatile, and suitable for on-site or remote scanning projects.
Better at capturing deep pockets, cavities, and hard-to-reach areas.
Laser handheld scanners can scan large parts while maintaining high accuracy.
Structured light handheld scanners are very fast, though generally with slightly lower resolution compared to desktop structured light systems.
Written by Belal Ahmad
Software By bitgraphicX