Fingerprint imaging and authentication

The IDEX SmartFinger® sensor is a swipe-type fingerprint sensor. The fingerprint authentication sequence is shown in Figure below.

The fingerprint sensor itself delivers calibrated image data in real time over the SPI interface. The complete fingerprint representation is built up line by line and recorded as the finger is swiped over the “single line” sensor array.

The image reconstruction can take place on a separate microcontroller or directly on the host processor in the case a PC or mobile phone applications. The patented, sensor specific image reconstruction principle is the core of IDEX’ IP, and the basis for the user-friendly, robust, high-quality imaging offered by the SmartFinger technology.