Manual

How Our 3D Scanner Works

The Matter and Form 3D Scanner is a laser-based scanner. Laser scanners work by

shining a laser at an object, using a camera to capture data that is returned from the

laser hitting the surface of an object and then using software to stitch all that data

together. On the Matter and Form scanner, as the lasers pass over the surface of an

object, data is generated at a rate of approximately 2,000 points per second. This

data is comprised of thousands of individual points that record things like surface

detail, distance from the camera, texture, and color. These thousands of points, when

viewed collectively, form a “point cloud” that is a direct representation of the

scanned object.

The scanner is very good at capturing organic shapes. Curves, surface detail and

outer geometry scan very well. Deep depressions and overlapping features, however,

are difficult for the scanner to capture accurately. For example, it would be able to

scan the outside of a drinking straw but not all the empty space on the inside of the

straw. Like a photo camera, the scanner can only capture what is in its field of view.

The Importance of Calibration

In order to maximize the scanner’s precision and accuracy, it’s highly recommended

users devote time to calibration whenever the scanner has been moved. Every

scanner will have tiny, unique differences as a result of the manufacturing process,

temperature fluctuations and physical placement, so it is necessary to allow the

software to properly measure and compensate for such differences (i.e., calibration).

Calibrating is especially important after a scanner is moved. All data captured by the

scanner are in relation to the dead center of the turntable. Because the turntable can

shift up to 1 mm, any potential shift can affect what the camera, lasers and software

consider to be the dead center of the turntable when constructing a point cloud.

Throughout the calibration process the scanner’s camera, lasers and software are

developing reference points in an XYZ coordinate system based on the geometries

and angles of the calibration box and its checkered squares. Upon completion, the

software and firmware will save these reference points when scanning all subsequent

objects until calibration is completed again and new reference points are saved.

What Happens During a Scan

The scanner uses two lasers to scan small to medium sized objects placed on its

rotating bed. One rotation provides 360° coverage of an object. For some small

objects, one full rotation (or pass) is enough to scan the whole thing. In order to

capture larger objects, the scanner’s head rises and automatically detects whether

there is more of the object to scan. Like building a virtual layer cake, the scanner

continues additional passes until the full height of the object is captured.

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