High Speed Optical Coherence Tomography System And Imaging Of Fingerprints

Optical Coherence Tomography is a kind of imaging technology that is in a period of rapid development.It has advantage of high resolution,high sensitivity,no-invasive and non-contact.The methods of OCT have been developed from Time-Domain OCT to Fourier-Domain OCT,with the research going on,the resolution and imaging speed of OCT improve a lot.It's widely used in medical imaging because of its high resolution and suitable imaging depth range.Fingerprint identification is an important point in modern security.Traditional fingerprint collection generally uses optical sensors.OCT is a new way to collect fingerprint.Compare with traditional methods,OCT system can effective get the fingerprint from dirty finger and find pseudo fingerprint.This paper explains basic theory of OCT system.The optical path of frequency domain OCT system is introduced and the derivation process of final imaging results is given.The paper calculate the transverse and axial resolution of frequency domain OCT system and explain the influence of structural parameters of different components on the overall imaging effect.For collect the fingerprints,this paper build a high-speed Fourier Domain OCT system,the paper introduce the whole process of built of system,include the connection to all instrument and data processing.In this thesis,several solutions are put forward to eliminate the instrumental error from scan mirror.The method make the imaging result accurate.Finally,fingerprints have been collected by OCT system built in our Laboratory,different scales of 2D and 3D imaging are shown in the end of the paper,imaging of pseudo fingerprint was used for contrast.From the experimental data,fingerprints and other features in finger were extracted.