There are many ways to capture 3D data from reality and a couple of weeks ago we got together with the folks at Shining 3D to take a closer look at their Einscan Pro+ scanner and see how it can be used to quickly capture detailed 3D surfaces. Many thanks to the guys at Print A World in Brooklyn, NY for hosting the demo.
How does structured light scanning work?
We’re glad you asked – it’s really rather clever! There’s a pretty neat article on Wikipedia that goes into more detail, but the simple answer is
Projecting a narrow band of light onto a three-dimensionally shaped surface produces a line of illumination that appears distorted from other perspectives than that of the projector, and can be used for geometric reconstruction of the surface shape (light section).
A faster and more versatile method is the projection of patterns consisting of many stripes at once, or of arbitrary fringes, as this allows for the acquisition of a multitude of samples simultaneously. Seen from different viewpoints, the pattern appears geometrically distorted due to the surface shape of the object. ~ en.wikipedia.org/wiki/Structured-light_3D_scanner
So – straight lines of light projected onto any real world object are distorted by that surface. This can be recorded as a contoured samples of that objects 3D shape and as more contour samples are built up, a complete digital 3D model can be built up.
If that’s a lot to wrap your head around, maybe some animated GIFs might help explain:
This entire scan only took around 2 minutes and was uploaded using the integrated Sketchfab exporter. It’s a very detailed model at 9.3 million faces so be warned it is a very large file and will take some time to load.:
Processing the data to for export doesn’t take long, and this is even more impressive considering the level of detail achieved with the recently released HD Prime Pack from such a monochrome and shiny subject.
Handheld vs. Turntable
EinScan Pro+ is a multi-function 3D scanner: it has a handheld scan mode and fixed scan mode in one piece of hardware. Using the Einscan Pro+ in handheld mode is great for when you have limited access to a subject but for certain objects the automated turntable mode is more suitable. In this workflow, the Einscan Pro+ is set on a tripod and directed at an automated turntable. You simply drop your subject onto the turntable and start the scanning process.
By re-scanning the subject in different orientations it’s possible to create a complete scan of an object. Thanks to the calibrated set up and software, all of this is achieved automatically without the need for manual markers. Resulting 3D models can be simplified and exported as OBJ, PLY, STL and ASC.
What is structured light scanning good for?
Due to the large data sets created and limits on projection distance, structured light scanning is ideal for small to medium sized subjects. Within this range however, pretty much anything goes and you can scan people, components, foods, clothing, artifacts and more. An additional colour module can be used to – you guessed it – capture in colour as well.
What do you need to capture 3D data with structured light scanning?
When using the Einscan Pro+ for structured light scanning you need:
- the handheld scanner
- a Windows PC with a discrete graphics card
- dedicated scanning software
The complete kit is relatively compact and very easy to use – you can find out more, including pricing, on the Shining 3D website and remember, you can upload directly to Sketchfab from the Einscan Software.