3D Laser Scanners are usually to use in the industry field. However, the commercial scanners is not only heavy but also expensive. It also need to use the complicate calibration process to improve its accuracy. The purpose of this study was to produce a tread depth measurement system. The principles we used was composed of triangulation measurement and image identification. The hardware we used was composed of camera lens of the mobile phone and laser line module. As the results, the two-dimensional images can be translated into three-dimensional space under 8 mm of the tread depth. The accuracy range was from -0.5 mm to 0.36 mm (Root Mean Square Error, 0.28mm). The unexpansive tread depth measurement system we produced can detect the tread depth rapidly and accurately.
