One of the most widespread biometric modalities is fingerprint recognition. The sensors work by capturing two-dimensional (2D) intensity images of the finger's surface. The distinguishing features (or minutiae) extracted from them are used to authenticate individuals by comparison with those recorded during enrollment.
Yet many problems remain. These include the highly variable quality of the images produced by a standard sensor, itself caused by acquisition conditions that are difficult to control: excessively high or low humidity, dirt on the sensor or finger, damage to the finger's surface (scars, deliberate removal of fingerprints, etc.), or the user applying the wrong amount of pressure. This limits the reader's performance and the reliability of authentication. New sensors have therefore been developed that can produce a three-dimensional representation of the finger. The resulting information, far richer than that conventionally acquired from a finger, allows the finger to be analyzed throughout its depth and makes it possible to segment most types of biological tissue. The interferogram is a recording of the interferometric signal obtained by recombining light backscattered by the tissue beneath the probe with a reference signal.
