Laser Principle of Three-Dimensional Foot Scanner in Foot Shape Reconstruction in Rehabilitation Medicine
In the foot shape reconstruction scheme of rehabilitation medicine, the core technology of the three-dimensional foot scanner is the laser triangulation method.
This principle, through non-contact scanning, accurately captures three-dimensional data of the foot, providing a millimeter-level precision basic model for customized corrective insoles, braces, or surgical planning. Its workflow is divided into three steps:
Laser Projection: Multiple groups of sensors project structured laser lines or dot matrices onto the sole, covering key areas such as the arch and heel. The laser forms deformation patterns on the foot surface, mapping contour fluctuations in real time.
Image Acquisition: High-resolution optical sensors capture laser deformation data within 0.2 seconds, generating a dense point cloud containing tens of thousands of coordinate points. This process can penetrate socks or slight sweat, ensuring data integrity.
Three-Dimensional Reconstruction: Algorithms automatically fit the point cloud, reconstructing a 1:1 foot model. For example, through speckle projection technology (a type of laser interferometry), the arch collapse angle (<15 mm indicates flat feet) or calcaneal varus deviation (>4° indicates varus feet) can be analyzed, directly outputting STL format files for 3D printing.
The advantage of this technology lies in avoiding manual measurement errors (accuracy up to 0.5 mm) and optimizing the design of rehabilitation schemes.
In rehabilitation applications, such as calcaneal varus correction, the three-dimensional model generated by laser scanning can directly connect to 3D printing systems to produce personalized osteotomy guides or braces, significantly improving surgical precision and patient comfort.
