Measurements of evanescent wave in a sandwich Lamb wave sensor

One method for evanescent wave measurement of the Lamb wave biosensor is proposed by putting another Lamb wave device above the first with the distance less than the evanescent field penetration depth in the liquid. The liquid layer is sandwiched with the two Lamb wave devices. The devices are interacted by an evanescent field; thus the evanescent wave can be studied. The mode is split by the interaction of the evanescent wave. The investigation of the evanescent field gives insight into acoustic biosensors and provides precise and multiparameter measurements.