3D scanners are revolutionising the manufacturing industry. Engineers and designers across the field are integrating them into their workflows — for a good reason. From automotive manufacturing to healthcare, consumer goods, and art, 3D scanning enables users to digitize physical objects in intricate details for 3D printing, structural analysis, and reverse engineering.
But the marketplace is brimming with different types of 3D scanning technologies. New users in particular might get lost in the sea of scanners. How can you choose the technology that works best for you?
Read on as we compare the most common 3D scanning technologies. Learn their strengths and drawback and find out which gives the results your operation needs.
Structured Light
Structured light 3D scanning is one of the most popular types of 3D scanner technology. These scanners — such as Peel 3.CAD — work by projecting a structured light pattern onto the scanned object. The light pattern may consist of horizontal or vertical bars, a crisscrossing diamond pattern, or some other shape, depending on the device.
As the light hits the object, it scatters back. Sensors on the scanner device detect the reflected light. Based on trigonometric triangulation, they calculate the XYZ coordinates of the reflection and build a 3D model based on this data.
Structured light 3D scanners used to use white light, but light of this wavelength doesn’t always work well in daylight. To this end, many structured light scanners today use blue light, which gives them better resistance to ambient lighting.
This scanning technology is popular for its fast speed, high accuracy, and the devices’ affordable prices. However, it can struggle to scan shiny or transparent objects, although it’s possible to mitigate this issue with 3D scanning sprays.
| Structured Light | |
| Pros | Cons |
| Affordable 3D scanners | Brightly lit environments can affect scan quality |
| High accuracy | Struggles with shiny, dark, or transparent objects |
| Fast scan speeds | Not ideal for very large objects |
| High resolution | |
| Doesn’t require safety gear | |
| Suitable for many industries | |
| Simple device operation |
Laser Triangulation
Laser triangulation-based 3D scanners, like Creaform HandySCAN, work similarly to structured light scanners. However, instead of a light pattern, they use a series of lasers to triangulate the scanned objects XYZ coordinates — hence the name.
The scanning devices project a number of laser beams at the object. Generally, the more lasers the scanner has, the more accurate results it can get. The laser beam bounces back from the scanned object, and the scanner’s sensors interpret its shape and size.
Since they’re quite similar, laser triangulation 3D scanning shares many of the advantages and drawbacks of structured light scanning. It can be extremely accurate and fast, and it may perform slightly better with transparent surfaces due to the intensity of the laser beam.
But laser triangulation scanners are often more expensive. These 3D scanners may also require users to wear safety goggles to protect themselves from the bright lasers.
| Laser Triangulation | |
| Pros | Cons |
| Extreme accuracy | Somewhat sensitive to ambient light |
| Fast scan speed | Can have issues with shiny, dark, or transparent objects |
| Can scan larger objects | Scanners can be costly |
| Easy operation | May need safety goggles |
| Highly versatile end-use cases | |
| Capable of low- and high-resolution scans |
Laser Pulse
Laser pulse 3D scanning systems, including Leica BLK360, also use lasers. But unlike laser triangulation, they don’t rely on triangulation. Instead, they calculate shapes and distances based on the speed of light.
The device sends out potentially hundreds of thousands of laser pulses per second. By measuring the time it takes for the laser pulses to bounce back, the 3D scanner can construct an accurate, large-scale 3D model. If the system has cameras, like Leica, it can even scan in full colour.
The main advantage of laser pulse 3D scanning is its ability to scan very large objects, such as entire rooms or buildings. With a rotating mirror, the scanner can cast the last pulses 360 degrees around itself.
But not every laser pulse scanner is used for scanning enormous things. Another popular application of the technology is intraoral dental 3D scanning, with devices like 3Disc Heron-IOS. These scanners use a rotating head to get an accurate 3D scan of the patient’s mouth, allowing the dentist to accurately plan treatment and even 3D print dental appliances.
Laser pulse scanning does tend to be rather slow. But if you need to scan big objects, you can’t hurry the process.
| Laser Pulse | |
| Pros | Cons |
| Can scan very large objects | Not suitable for scanning smaller objects |
| Good resolution and accuracy | The scanner must remain stationary while scanning |
| Simple usability | Typically captures point cloud data which can be challenging to work with in some CAD software |
| 360° scanning field of view | |
| Scans over long ranges |
Photogrammetry
Photogrammetry doesn’t rely on reflected light like the above technologies. In fact, it doesn’t use a 3D scanner at all. All you need for photogrammetry is a normal camera.
To digitise an object using photogrammetry, you must take a high-quality photograph of it from all angles. You can then use specialised software to stitch the photographs into a 3D model.
This technology is rather popular since it doesn’t need any special physical equipment. It can be very cheap as you only need a good camera. It’s also capable of capturing textures and large outdoor areas rather accurately.
But photogrammetry is very difficult. The software it uses is rarely straightforward and it takes a lot of processing power and time to form the models. Additionally, your camera must be suitably high-resolution to get satisfactory results.
| Photogrammetry | |
| Pros | Cons |
| Can be affordable | Relies on special software |
| No special equipment necessary | Forming 3D models is slow |
| Photographing objects is fast | Accuracy depends on the quality of the camera |
| Good accuracy |
Contact Scanning
Last but not least, we have contact scanning, also called digitising. These 3D scanners don’t use cameras at all. Instead, they capture an object’s surface details by physically touching it with a sensitive probe.
The probe moves across the scanned object, recording its contours and surface structure. The scanner must get enough contact points to accurately recreate the object digitally. To this end, some contact 3D scanners use articulated robotic arms to move the probe.
The major advantage of contact scanning is that it’s entirely surface agnostic. It can accurately capture even transparent objects.
However, contact scanning is very slow. It takes a long time to run the probe all over the object. It’s also limited in how complex shapes it can capture — the probe may not reach every nook and cranny.
| Contact Scanning | |
| Pros | Cons |
| Can scan transparent, shiny, or dark objects | Very slow scan speed |
| Accurate | Not suitable for large objects |
| Works with small objects | The probe could damage fragile objects |
Choose the Right 3D Scanning Technology
You now know the major types of 3D scanning, their working methods, and the pros and cons. Armed with these details, you can start narrowing your options down based on how the technology fulfils your needs.
When picking a 3D scanner for your business, ask yourself these questions:
- How large objects will I scan?
- Do my objects have transparent, shiny, or dark surfaces?
- Do I need high-accuracy or high-resolution scanning?
- How important is scanning speed to me?
- Will I scan many different kinds of objects or only one type?
- What is my budget?
Answering these questions can help you choose the 3D scanning technology that works best for you. But if you still feel a bit lost, here are our recommendations:
- For versatility, ease of use and an affordable cost, consider a structured light 3D scanner, like Peel 3.CAD.
- Laser triangulation 3D scanners, such as Creaform HandySCAN, let you scan intricate details quickly.
- Laser pulse 3D printers, like Leica BLK360, are your go-to solution for scanning very large objects and spaces.
- For dental applications, check out intraoral scanners like 3Disc Heron-IOS.
With these suggestions, you can choose the right type of 3D scanner. Introduce 3D scanning to your business and begin capturing parts, objects, and entire houses in stunning detail.
If you’d like to learn more about various 3D scanning technologies, get in touch with the friendly Solid Print3D experts! Call us at 01926 333 777 or email us at info@solidprint3d.co.uk.
