非接触式指纹采集与识别的研究

为了构建一个结构紧凑、实时、高效、小型的指纹采集识别系统,提出了非接触式光学采集方法.即采用激光或非相干光源,利用激光透射、扫描和非相干光照射,通过超半球浸没透镜和双胶合透镜等组合的光学系统,运用光学非接触式方法实现完整、清晰的指纹图像的采集,这种方法有效地避免了接触式所造成的指纹的旋转、扭曲和变形,提高了采集图像的质量.从而为利用空间光调制器实现指纹的实时傅里叶相关识别提供了有效的保证.

Study on Indirect-contact Collection and Identification of Fingerprint Images

In order to construct a compact, real-time, high efficient, small-scale fingerprint collection-identification system, a new method of fingerprint indirect-contact collection was proposed. Laser or incoherent light source was adopted and the principle of laser transmission, scan and incoherent light irradiation were applied in the experiment. The integrity clear fingerprint image was indirect-contact collected by using optical system that was consisted of super-hemisphere-immerge lens and pair of veneer lens. The approach avoids fingerprint rotation, distortion and out of shape effectively caused by direct-contact method and improves image quality. Thus the approach offers the effective assurance that utilize spatial light modulator can realize real-time Fourier correlate identification of fingerprint.