The present invention concerns a display device comprising: at least one micro-reaction-chamber (2) to which is associated an inlet (3a) to receive a reaction liquid and an outlet (4b) to discharge the product of reaction; at least one charge micro-channel (3) connected to said inlet (3a) and at least one discharge micro-channel (4) connected to said outlet (4b); a porous substratum (2a) situated inside said micro-reaction-chamber (2); at least one chemical and/or biological element (22) immobilised on the porous substratum (2a) capable of generating light emission when in contact with the reaction liquid.