基于小视场结构光的指纹三维形貌测量系统

Fingerprint three-dimensional shape measurement system based on small field of view structured light

  • 摘要: 针对传统二维指纹采集技术存在的信息失真,卫生风险等安全问题,利用结构光三维测量技术对指纹表面形貌进行高精度三维测量。通过研究解算相位方法、远心成像三维检测模型、快速标定算法,可解决小视场三维测量系统精度较低,标定复杂的问题。实验中搭建了三维指纹采集系统,实现了手指指纹的采集及三维形貌的测量。在视场为39.9 mm×26.6 mm且工作距离为138 mm的条件下,系统的测量精度达到了30 μm。相比传统方法,误差显著降低,指纹采集速度优于1.5 s。相关研究工作有助于解决三维指纹获取成本过高、重建精度不高的问题,为进一步提高警方物证勘验、痕迹检验鉴定中的指纹测量精度、识别率、检测实时性提供技术支撑。

     

    Abstract: To address issues with traditional 2D fingerprint acquisition technology, such as distortion and hygiene risks, a structured light 3D measurement system for high-precision fingerprint topography measurement was introduced. By optimizing the phase calculation, telecentric imaging 3D detection model, and fast calibration algorithms, the problems of low accuracy and complex calibration of small field of view 3D measurement system could be solved. A 3D fingerprint acquisition system was built in the experiment, achieving the collection of fingerprints and the measurement of 3D morphology. Under the conditions of a field of view of 39.9 mm×26.6 mm at a working distance of 138 mm, the measurement accuracy of the system reaches 30 μm. Compared with traditional methods, the errors are significantly reduced, and the fingerprint collection speed is better than 1.5 s. The relevant research work is conducive to solving the problems of high acquisition cost and low reconstruction accuracy of 3D fingerprints, providing technical support for further improving the measurement accuracy, recognition rate and real-time detection performance of fingerprints in police physical evidence examination and trace examination and identification.

     

/

返回文章
返回