![]() Philips has also worked with Ethentica to combine their technologies, but without known product. TFT optical / TFT optique Philips replaces the CMOS sensor by a TFT display, used as sensor. In July 2005, NanoIdent unveils a flexible fingerprint sensor using polymer/organic photodetector. Mitsumi & NEC proposes the same but with a sweep sensor. NEC and Delsy (and Secom?) use a CMOS camera which is the size of the finger, with a fiber optic in-between, the light is coming from the edges in this case. Mitsubishi proposes to read the fingerprint with a regular camera. It is also possible to directly read the light transmitted by the finger. (2005) TBS launch a touchless sensor with the "Surround Imaging". The BERC lab from Yonsei University (Korea) also developped a touchless sensor (2004). Thales (formerly Thomson-CSF) also proposed the same, but with the use of a special powder to put on the finger. TST removed the prism by directly reading the fingerprint, so the finger does not touch anything (but still need a guide to get the right optical distance). Casio Alps ElectricĪs well as Digital Persona with the Firefly Digital Persona Firefly Cecrop seems to have abandonned this device Kinetic Sciences Paper describing the sensor Cecrop/SannaedleĬasio + Alps Electric uses a roller with the sensor inside. Kinetic Sciences and Cecrop/Sannaedle have proposed sweep optical sensors based on this principle. Nagoya University uses a micro-collimator instead of the fiber optic, enabling direct fingerprint comparison. Generally, one fingerprint is taken at a time, but some devices are able to acquire several fingers at a time. Here is the example of the Compaq fingerprint reader (CMOS camera, around 2000). Optical readers -Reflection Many companies are offering such devices, this is a common technology. (FTIR: frustrated total internal reflection). The finger is illuminated from one side with a LED while the other side transmits the image through a lens to a camera. Reflection The oldest 'live-scan' readers use frustrated refraction over a glass prism (when the skin touches the glass, the light is not reflected but absorbed). Ink and paper are the tried-and-true way to take fingerprints, but technology has found ways to eliminate smudges and ink stains. Reflection Transmission Sweep, sweep with a roller Touchless TFT Fingerprint sensing techniques 0920 2007 Biometrics Tech. ![]()
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