Fingerprinting technology is the most mature biometric identity verification tool. A combination of factors including non-invasive data acquisition, global acceptability, and the existence of large databases make fingerprinting the most used biometric identity verification technology.
Various public and private enterprises have already started using fingerprinting as an alternative to traditional identity verification mechanisms such as username-password, VPN token, other unique personal identifiers, etc. While the popularity of using fingerprints as a means for identity verification is on an upswing, fingerprint capture is an area that has significant room for improvement.
Fingerprint image acquisition is of vital importance in any fingerprint-based authentication system. Current fingerprint capture technologies rely on one of the two approaches:
- Applying ink (or similar pigments) to the finger and then pressing or rolling the finger onto a paper surface
- Imaging the finger ridges as they touch (or press on) a glass (or glass-like -silicon, polymer, etc.) surface
- Typical problems associated with available imaging technologies include:
- Distortion resulting from pressing the finger against the sensing surface causing skin deformation thus compromising the quality of the captured fingerprint and resulting in distorted spatial data, inconsistent image quality, partially captured fingerprint, etc.
- Slippage and smearing due to moist fingers
- Improper contact due to finger dryness
- Leaving a latent fingerprint on the imaging surface
- Accumulation of dirt on the imaging surface resulting in sub-optimal capture
- Degraded image quality resulting from wear and tear of capture surface coatings
- Device wear and tear associated with the capture process introduces additional maintenance and repair costs.
Above limitations are addressed through a Touchless 3D Fingerprint Imaging System (T3FIS) capable of capturing 3D fingerprint data in conjunction with a range based imaging sensor. This is an alternate approach to a conventional 2D fingerprint capture, designed to improve the quality of the captured fingerprint by introducing a touchless, 3D fingerprint capture technology which takes advantage of sweep imaging enabled by laser-based detection and ranging. The approach is based on merging multiple range images to produce a continuous description of the entire finger.The method will potentially result in improved fingerprint matching metrics and improved efficiency for the end user.
|Advantages of T3FIS over Contact-based Fingerprint Identification (CFI).e|
|3-D data||More accurate data and better image quality result in better matching rates.
New matching features based on the 3D data will lead to better identification.
Capture of 3-D images with no possibilities of print deformation will improve consistency and reliability
|Non-contact||Better image quality is achieved because there is no contact of the print with the scanner to distort the image. Extremely consistent prints. No cleaning between uses.
Convenient for the user – touch-less, one-time, hygienic
|Latency||No latent fingerprints|
|Physical Condition||Independent of skin conditions|
|Anti-spoofing||Tests for finger curvature, ridge modulation and segmentation defeat common deceptive techniques.|
|Automated||The device can function independently of an operator. Quality of the print no longer tied to the skill of operator manipulating the subject’s hand.|
|Backwards compatible||The 3D fingerprint image is flattened as a 2D rolled fingerprints and streamed back to the server for further processing and feature collection and be compatible and consistent with existing databases.This way we maintain a simple framework and keep the cost down.|
|Go/No go||Real time image quality assessment will let operator know immediately if the print acquired is of acceptable quality or if the subject should repeat the process.|