Abstract
Objective
To investigate whether the accuracy of 3D laser scanning is influenced by the angles and number of scans.
Methods
Using a 3D laser scanner, 10 manikins with facial markers were scanned at 7 horizontal angles (front view and at 20°, 45°, and 60° angles on the right and left sides). Three-dimensional facial images were reconstructed by 6 methods differing in the number and angles of scans, and measurements of these images were compared to the physical measurements from the manikins.
Results
The laser scan images were magnified by 0.14 - 0.26%. For images reconstructed by merging 2 scans, excluding the front view; and by merging 3 scans, including the front view and scans obtained at 20° on both sides; several measurements were significantly different than the physical measurements. However, for images reconstructed by merging 3 scans, including the front view; and 5 scans, including the front view and scans obtained at 20° and 60° on both sides; only 1 measurement was significantly different.
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