A biometric authentication device uses biometric information to perform biometric authentication by comparing biometric data for authentication, recorded in advance, with biometric data obtained during authentication. The biometric authentication device is characterized in that it is provided with: a near-infrared light radiating unit which radiates near-infrared light onto a finger an image-capturing unit which captures images of biometric data obtained as a result of the near-infrared light, that has been radiated from the near-infrared light radiating unit, passing through the finger a control unit which acquires the biometric data acquired by the image-capturing unit and a visible light radiating unit which radiates visible light into a finger insertion portion into which the finger is inserted. The biometric authentication device is also characterized in that the visible light radiating unit begins radiating visible light before the image-capturing unit acquires the biometric data, and if the brightness of the captured image of the biometric data acquired by the image-capturing unit is greater than a brightness suitable for authentication, the control unit reduces the brightness of the radiation from the visible light radiating unit, and compares the biometric data obtained with the reduced radiation brightness with the biometric data for authentication recorded in advance.La présente invention concerne un dispositif dauthentification biométrique qui utilise des informations biométriques pour exécuter une authentification biométrique au moyen de la comparaison de données biométriques dauthentification, enregistrées à lavance, avec des données biométriques obtenues au cours de lauthentification. Le dispositif dauthentification biométrique est caractérisé en ce quil est pourvu : dune unité de rayonnement de lumière du proche infrarouge qui soumet un doigt à un rayonnement de lumière du proche infrarouge dune unité de capture dimages qui capture des images de don
