palmprints

Palmprints are digital or physical impressions of the entire palm surface, capturing skin texture, ridge patterns, and creases. They extend beyond the area covered by fingerprints, including the thenar and hypothenar regions and the central palm. Like fingerprints, palmprints are formed by friction ridges unique to an individual; they also include palmar creases that appear when the hand is flexed. Palmprints are used in forensics and biometric identification.

Analyzing palmprints involves examining friction ridge patterns and palmar creases. The ridges can form various flow patterns, with local features such as ridge endings and bifurcations used for matching. The palm also contains major creases that reflect hand posture, and databases segment the palm into regions (central palm, thenar, hypothenar) to support feature extraction and comparison.

Collection and use: In forensic science, palmprints are collected at crime scenes or from suspects; in civil applications, live-scan devices capture palmprint images for identity verification. Palmprints can be obtained via ink impressions or digital scanners, and software compares ridge patterns and texture against a stored template. Palmprint biometrics can be used alone or combined with fingerprints to improve recognition accuracy.

Limitations and considerations: Image quality depends on skin condition, moisture, pressure, and cleanliness, and aging or injury can affect prints. Some individuals yield partial or less distinct impressions, which can complicate matching. Privacy, consent, and legal standards govern the collection and use of palmprints in various settings.