BRS BioLock, User Manual

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To ensure correct operation of BioLock
®
it is imperative that the guidelines
below be followed without question or variation.
A fingerprint is a characteristic pattern that is unique to the individual person
bearing it. Although fingerprint patterns vary widely from type to type, each
fingerprint has a small central area around which the remainder of the pattern
is distributed. This central area is the “core” of the fingerprint. Typically, this
core is opposite the point that the fingernail emerges from the cuticle.
While the matching algorithm of the BioLock system is quite tolerant to non-
optimum finger placement, centering the core on the sensor will give the best
possible performance. Find your fingerprint cores and verify that the core
location of your fingerprints is approximately as described. Most fingers will
follow this general rule. If your core location is very different, adjust your
finger placement accordingly.
Capture the full area of the fingerprint by contacting the sensor surface with
the finger placed flat on the sensor, as opposed to presenting only the tip of
the finger.
The fingertip alone contains insufficient image data for a high-quality
fingerprint.
The ridges in this area are mostly parallel lines, with few distinct
minutiae
from which to construct an identification template. It is unlikely that the image
management algorithm will actually permit enrollment, but if it does, such a
feature-poor environment can lead to False Acceptance errors.
Lay the finger down flat, lightly but firmly on the sensor make sure that the
finger is placed perpendicular to the sensor. This results in minimal
distortion of the skin. If the finger is pulled or pushed left or right, forward or
back, the image is distorted and the fingerprint quality is reduced.
Note: Do not roll the finger as you might when taking a traditional ink-and-
paper image! Keep the finger flat and motionless against the sensor detection
surface during the imaging process.
The BioLock matching algorithm can tolerate non-optimum entry angles up to
±15°, in addition vertical displacement ±5mm and laterally ±7mm but the
performance of the matching algorithm may be affected by this misalignment.