Biometric sensors are semiconductors with embedded algorithms that are used in security systems or environments that require user authentication. They produce electrical signals from fingerprints or other physical characteristics in biometric access control systems. Biometric sensors consist of an array of tiny electrodes and an analog-to-digital converter (ADC) that digitizes information from the sensor array. In fingerprint access control systems, the user presses an index finger to a scanning device that includes a biometric sensor. The varying capacitive values across the sensor array are then converted into an image of the fingerprint. Other components of the biometric access control system then compare the image to a stored template.

Applications for biometric sensors include computer and network security, building and facility access, mobile device security, government and military identification, medical records, kiosks and point of sale (POS) terminals.