How does 3D scanning work?

Introduction

What is 3D scanning, how does it work and how can this be used for 3D printing? Let’s find out.

What is 3D scanning?

3D scanning is a process of analyzing an object from the real world, to collect all the data in order to recreate its shape and appearance, digitally. Thanks to this process, the object can become a 3D model, which could help you as a base for the 3D project you are about to develop, but it can also be useful to reconstruct, analyze, or simulate ideas.

Different machines and methods exist to 3D scan objects. You might not know it, but there are different ways possible to create a digital version of a real object. We are going to see more in detail of how each of them works. There are a lot of different 3D scanning methods, but today, we will focus on three of them, that we can consider as the main ones: Laser 3D scanning, photogrammetry, and structured light scanning. The choice of the 3D scanning technique will be made regarding your project or its context.

How does 3D scanning work?

Laser 3D scanning

Laser 3D scanning is certainly the most common and used 3D scanning technique. Digitally capturing the shape of the object using laser light to get a digital representation of the real object. These 3D scanners are able to measure really fine details and capture free-form shapes to generate highly accurate point clouds.

This laser scanning technique is perfect for measurement and inspection of complex geometries. It allows getting measurements and data from where it is impractical with traditional methods!

A scanner using laser light is a little bit like a camera: it can only capture what is in its field of view. With this process, a laser dot or line is projected on an object from the device and a sensor measures the distance to the surface of this object.

By processing this data, it can be converted into a triangulated mesh, and then a CAD model.

Photogrammetry

Photogrammetry is a science of making a measurement from photographs! It seems pretty simple, no? This method uses the parallax obtained between several pictures, taken from different points of view. Photogrammetry can be used to record complex 2D and 3D motion fields. It imitates the stereoscopy of the binocular human vision, and it is used to get all information of existing physical objects. Indeed, this process collects the data regarding the shape, the volume, and the depth of the subject that you are trying to scan.

This is the method used to turn several pictures into an accurate 3D design. It won’t allow you to get the most accurate result, but by using good photogrammetry software you could actually reach a satisfying result!

Structured Light Scanning

With this Structured Light Scanning method, one of the camera positions used in previous scanning methods is actually replaced by a projector that projects different light patterns on the surface of an object. The way the objects distorts these patterns is recorded, allowing to create the 3D scan.

The structured light scanning process is used in facial or environment recognition technologies.

How to use 3D scanning?

3D scanning can be a faster and easier technique to create a 3D model for 3D printing if you just want to recreate an existing object. Once you have your 3D model, you can add the modifications to it, it can actually be a great basis to start your project.

What are the applications of these 3D scans? The medical sector is really making the most of this scanning technology. It is also helping to create made to measure prosthesis for patients, from 3D scans. The use of 3D scans is already quite popular in the dental sector, for example, to observe, simulate options, or even create some dental devices, like braces, implants, and dentures. Using 3D scanning and 3D printing is perfect to avoid all the disadvantages of molds and the whole process of creating these molds.

3D scanning has numerous benefits. It is even a solution to stock data that we can use later. Do you know that some 3D scans of Notre-Dame, the French cathedral that partially burned on the 15 April 2019, could be used in order to restore it? 3D scanning has a lot of potentials.

We hope this blog post helped you to see clearly how 3D scanning techniques are working. Are you already using some of these 3D scanning methods? Tell us everything in the comments. If you are interested in 3D scanning, check out our blog post of the best 3D scanners, to see which one could actually help you with your project.

Don’t hesitate to subscribe to our newsletter!