It is disclosed a device for measuring a concentration of glucose, for example, in a translucent piece of a body, like an earlobe, a tissue connecting two fingers, a nasal ala, or a cheek. The piece is illuminated by a linearly polarized laser beam at a certain polarization direction. Consequently, a diffused radiated light is emitted from the piece, including a directed beam. The device includes a polarizing beam splitter which receives the directed beam, a lens, a sensor array, and means for connecting to a processor. The splitter splits components of the directed beam at two mutually orthogonal linear polarization directions into two polarized beams propagating at two respective different directions. The lens images the distribution of the directed beam on the translucent piece on two spatially separated groups within the sensor arrays. The processor defines pixel pairs from a first and second images which correspond to a same point on the second surface of the translucent piece, and subtracts the first pixels from the respective second pixels to get a difference image. In addition, the processor calculates the variance of the difference image, and calculates the desired concentration accordingly.Linvention concerne un dispositif permettant de mesurer une concentration de glucose, par exemple, dans une partie translucide dun corps, telle quun lobe doreille, un tissu reliant deux doigts, une aile du nez, ou une joue. La partie est éclairée par un faisceau laser polarisé linéairement dans une certaine direction de polarisation. Par conséquent, une lumière rayonnée diffuse est émise à partir de la partie, y compris un faisceau orienté. Le dispositif comprend un séparateur de faisceau de polarisation qui reçoit le faisceau orienté, une lentille, un réseau de capteurs, et un moyen pour la connexion à un processeur. Le séparateur sépare les composantes du faisceau orienté dans deux directions de polarisation linéaires mutuellement orthogonales en deux faisceaux polaris
