A device (100) for evaluating a humidity characterization parameter indicative of a dry eye, the device comprising: (a) an alternating current source (102) adapted to connect to a power supply (104) and to produce an alternating current； (b) an electrode arrangement (110) having at least a first electrode (112) and a second electrode (114) electrically connected to said alternating current source (102), said first electrode (112) electrically separated from said second electrode (114) by an electrically insulating region (120), said arrangement (110) having at least one semi-rigid region that fixes said electrodes in a separately arranged manner and is adapted to contact soft tissue on the inner surface of a eyelid of the eye, and said electrodes and said insulating region which are composed of biocompatible materials； and (c) a processor (150), associated with said electrode arrangement (110), wherein, when said electrode arrangement (110) is supplied with said alternating current, and is arranged against the soft tissue, the soft tissue does an electrical bridge between said electrodes (112, 114) to form an electrical circuit, such that an electrical signal is produced by said alternating current passing from the first electrode to the second electrode through soft tissue, said processor (150) which is adapted to receive an electrical information based in vivo that originates from said electrical signal, through said circuit, and to produce an output referring to, or derived from, the humidity parameter, based on said electrical information in vivo , said processor (150) which is designed and configured to compute the parameter of humidity in the soft tissue, at least partially based on said electrical information in vivo, and based on an empirical correlation lyric between said in vivo electrical information and said humidity parameter, said empirical correlation that includes an inverse relationship between an electrical impedance derived from said in vivo elect
