潜指纹是刑事侦查中重要的证据。为了研究基于紫外偏振成像技术的潜指纹无损检测,利用背照式sCMOS探测器,提出了紫外偏振成像方案。分析了紫外偏振成像的基本工作原理,设计了由双胶合透镜光学系统、异步旋转机械结构和自动调谐电子学系统构成的分时型紫外偏振成像探测系统,并通过实验验证了该系统的功能和性能。结果表明,利用该系统可以实现对潜指纹等弱特征目标的无损检测。相较于传统强度信息检测,该方法获取的偏振信息提高了目标与背景的对比度,凸显了目标的细节特征,为偏振成像探测应用于潜指纹无损检测提供了实验依据。

Latent fingerprint is an important evidence in criminal investigation. In order to study the nondestructive detection of latent fingerprint based on ultraviolet (UV) polarization imaging technology, the back-illuminated sCMOS detector is used to study the UV polarization imaging scheme. The basic working principle of UV polarization imaging is analyzed, and the time-division UV polarization imaging detection system consisting of double-glued lens optical system, asynchronous rotating mechanical structure and automatic tuning electronics system is designed. The experiment verifies the function and performance of the system. The results show that the system can realize the non-destructive detection of weak feature targets such as latent fingerprints. Compared with the traditional intensity information detection method, the polarization information obtained by the method improves the contrast between the target and the background, highlights the details of the target, and provides experimental basis for the application of polarization imaging detection in latent fingerprint nondestructive detection.