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3D measurement opens up many possibilities. Just imagine, for everything that can be found in the real world, you can get a digital model in just a few minutes.
Every day, thousands of companies use 3D measurement software to:
- Creation, reverse engineering of CAD models of real products with lost drawings, as well as for modeling a new design.
- Quality control of products by comparing their geometry with a reference CAD model
- Manufacture of customized parts and products for medicine, dentistry, advertising and fashion industry
- Scanning of buildings, industrial premises to create actual building models
This is not science fiction. 3D measuring scanners and related software are now available to many. Scanners are fast, inexpensive and very accurate in measurements. Processing software is more automated, gives better results and works faster than ever before
What are 3D measuring scanners?
There are many different devices that can be called 3D measuring scanners. Any device that measures details in the real world using lasers, light sources, or X-rays and generates point clouds or polygon meshes can be considered a 3D scanner. They go by various names, including 3D digitizers, laser scanners, white light scanners, industrial CT (computed tomography), LIDAR, and others. The common unifying factor of all these devices is that they capture the geometry of physical objects with hundreds of thousands or millions of dimensions. In addition, They can also be called optical measuring machines.
Why do you need software?
Because scanners collect huge amounts of data, special reverse engineering software such as Geomagic is needed to convert the data into something usable by other software. Depending on what the scan data will be used for, Geomagic can do many different things with it. The most common applications are reverse engineering, geometry control, digital archiving, or 3D printing. Dedicated software like Geomagic is the fastest and easiest way to unlock your full potential.
How do 3D measurement methods work?
There are many different 3D measurement methods based on different visualization principles. In addition, some technologies are ideal for measuring small parts, while others are better for scanning medium to large dimensions.
Laser triangulation 3D scanners
Laser triangulation scanners use one or more laser lines to scan across an object. The sensor captures the radiation reflected from the object, and using trigonometric triangulation, the system calculates the distance from the object to the scanner.
The distance between the source and the sensor, as well as the angle between the laser and the sensor, are known very precisely. When laser light reflects off a scanned object, the system can determine at what angle it returns to the sensor, and therefore the distance from the source to the surface of the object.
Structured light 3D scanners (white or blue light)
Structured light scanners also use trigonometric triangulation, but instead of looking at laser light, these systems project a series of linear structures onto an object. Moreover, by examining the edges of each line in the pattern, they calculate the distance from the scanner to the surface of the object. Basically, instead of the camera seeing the laser line, it sees the edge of the projected pattern and calculates the distance in the same way.
| Type of laser scanner | Laser triangulation | structured light |
|---|---|---|
| Advantages | Many applications More portable More efficient at scanning rough parts Less environmentally sensitive |
Usually more accurate Can usually run at lower (better) resolution Less noise when scanning |
| Flaws | Less accurate than structured light Working with higher (worse) resolution Getting information with more noise |
Limited scanning area Usually not portable and require special working conditions More sensitive to surface quality (requires preparation of the part for scanning) Requires specialized lighting |
Pulse-based 3D laser scanners
Laser pulse scanners, also known as time-of-flight scanners, are based on a very simple concept: the speed of light is measured very precisely, so if we know how long it takes for a laser to reach an object and bounce back into the sensor, we know how far this object is located. These systems use picosecond-accurate circuitry to measure the time it takes millions of laser pulses to return to the sensor and calculate the distance. By rotating the laser and sensor (usually through a mirror), the scanner can scan up to 360 degrees around itself.
Phase Shift 3D Laser Scanners
Moreover, phase shift systems are another type of time-of-flight based 3D measuring technology. They work conceptually similar to pulse-based systems. In addition to pulsing the laser, these systems also modulate the power of the beam, and the scanner compares the phase of the laser sent and then returned to the sensor. The phase shift measurement is more accurate, resulting in a more accurate result.
| Type of laser scanner | Advantages | Flaws |
|---|---|---|
| Based on impulses | Work at very long distances up to 1000 m | Less accurate Slower data collection Noisy information collected |
| with phase shift | More accurate Scanning process faster Less noise |
Medium range (up to 200m) |
