Contactless fingerprint acquisition apparatus, the apparatus comprising: - a casing defining a cavity; - a space for receiving a finger of a user; - a transparent wall forming a window between the cavity and the space for receiving the finger; - a translucent wall arranged opposite and remote from the transparent wall so as to provide the space between them; - a lighting source contained in the cavity and configured to emit illumination light illuminating the space; - a camera configured to acquire an image of a fingerprint of the finger, when the finger is received in the space, without coming into contact with the apparatus; the apparatus further comprising a polarization system (20, 22) configured to: - polarize the illumination light in a first direction before the illumination light reaches the space; - polarize the illumination light in a second direction after the illumination light has passed through the space, with the second direction being different from the first direction; - polarize ambient light in the second direction emanating from outside the apparatus and propagating towards the camera, before the ambient light reaches the space; and - polarize the ambient light in the first direction after the ambient light has passed through the space, wherein the polarization system (20, 22) comprises a first polarizer forming or being attached to the transparent wall and being configured to: - polarize the illumination light in the first direction before the illumination light reaches the space; and - polarize the ambient light in the first direction after the ambient light has passed through the space, and before the ambient light reaches the camera; wherein the polarization system further comprises a second polarizer attached to the translucent wall and being configured to: - polarize the illumination light in the second direction after the illumination light has passed through the space; and - polarize the ambient light in the second direction before the ambient light reaches the space. - a casing defining a cavity; - a space for receiving a finger of a user; - a transparent wall forming a window between the cavity and the space for receiving the finger; - a translucent wall arranged opposite and remote from the transparent wall so as to provide the space between them; - a lighting source contained in the cavity and configured to emit illumination light illuminating the space; - a camera configured to acquire an image of a fingerprint of the finger, when the finger is received in the space, without coming into contact with the apparatus; - polarize the illumination light in a first direction before the illumination light reaches the space; - polarize the illumination light in a second direction after the illumination light has passed through the space, with the second direction being different from the first direction; - polarize ambient light in the second direction emanating from outside the apparatus and propagating towards the camera, before the ambient light reaches the space; and - polarize the ambient light in the first direction after the ambient light has passed through the space, wherein the polarization system (20, 22) comprises a first polarizer forming or being attached to the transparent wall and being configured to: - polarize the illumination light in the first direction before the illumination light reaches the space; and - polarize the ambient light in the first direction after the ambient light has passed through the space, and before the ambient light reaches the camera; - polarize the illumination light in the second direction after the illumination light has passed through the space; and - polarize the ambient light in the second direction before the ambient light reaches the space.