3D Scanning - is the process of analyzing a real-world object or environment to collect data on its shape and sometimes its appearance, like the color and texture of the object. The collected data can then be used to construct digital 3D models.
At Vision Miner, we use and sell a full line of 3D scanners -- check out visionminer.com/einscan to see all those. Right now, though, I’m going to talk about the different types of 3D scanning, so you can get an idea of what’s out there.
So, first, let’s talk about the different types of scanning technology.
3D scanning actually comes in many forms, some you might already be familiar with. CAT scans create 3D models of the insides of the human body and your modern smartphone sitting in your pocket right now 3D scans your face to unlock it.
Professional 3D scanners however can use a variety of different technologies, each with their own pros and cons. These can easily be split into two categories: contact and non contact. For this video, we’ll focus on the latter of the two.
Contact scanning technologies like CMM or coordinate measuring machines basically take a very sensitive probe and run it across the surface of an object, recording data and comparing it to its digital cad model. Pretty much anywhere where accuracy down to the smallest measurement is of utmost importance, you can find CMM machines.
Non-contact scanning technologies like these four from Shining 3D, use a variety of technologies to capture their data.
ToF or Time of Flight -- this uses a laser light to probe the subject of the scan. A laser rangefinder gets the distance of a surface by timing the round-trip speed of a pulse of light. This is usually great for large scale objects, entire rooms, or even entire buildings. Unfortunately, like the iphone, they’re not super accurate with details, and the resolution of the scans don’t get close to the next types of scanners.
Hand Held Lasers - these use triangulation with an actual laser and multiple sensors, and of the lineup that we have here, this is the EinScan HX -- you can get details down to 0.05mm or 50 microns. Another benefit is that it works with dark and reflective objects, unlike the next technology.
Structured and Modulated light. Most 3D Scanners use this technology -- it projects structures of light (think QR code patterns) as well as modulating bars of light that change back and forth. It then reads this data and calculates the shape and size of the part using algorithms.
Lastly, we have Photogrammetry - this basically takes many photographs from different angles, calculates all the differences, and chunks out a solid 3D model -- however, a big disadvantage of this is that it’s not measuring while it’s scanning, unlike all the other methods -- but it can work great, especially on a budget, and depending on your photographs and style of photography, it can also be very accurate.