Patent ID: 8149088

Claim:
An optical biometric acquisition device comprising: a prismatic optical element comprising two opposite faces and of which at least a part of one face appears in a window and constitutes an application surface for placement of a body member of which a biometric image is intended to be formed, and illumination means arranged with respect to the prismatic optical element so that the illumination means illuminates said window from inside the prismatic optical element, and, if there is a body member placed on said application surface of the window, they form a biometric image of said body member by total reflection, means for presenting luminous information which are arranged under the prismatic optical element and approximately next to said window so that they transmit an externally perceptible image of luminous information through the window without total reflection, whereby the image of luminous information appearing through said window can be perceived by an observer when there is no body member placed on said application surface, wherein the means for presenting luminous information are separated from the illumination means and wherein the device comprises control means capable of inhibiting the means for presenting luminous information when a body member is placed on said application surface.