A flexible proximity sensor fully fabricated by inkjet printing is proposed in this paper. The flexible proximity sensor is composed of a ZnO layer sandwiched in between a flexible aluminum sheet and a web-shaped top electrode layer. The flexible aluminum sheet serves as the bottom electrode. The material of the top electrode layer is nano silver. Both the ZnO and top electrode layers are deposited by inkjet printing. The fully inkjet printing process possesses the advantages of direct patterning and low-cost. It does not require photolithography and etching processes since the pattern is directly printed on the flexible aluminum sheet. The prototype demonstrates that the presented flexible sensor is sensitive to the human body. It may be applied to proximity sensing or thermal eradiation sensing.

Micromixers are the devices which have the ability to mix liquids uniformly. However, a Tesla valve has the potential for micromixer development because of its simple structure and special flow mechanism. In this study, a numerical simulation analysis of a new Tesla-type micromixer was designed by placing a flow plate into a micromixer, which has a contact angle of 30° with the channel wall. The optimization of the geometric parameter, aspect ratio (AR) and the Reynolds number (Re) effect is discussed. The results show that the optimal geometric parameters of the unit Tesla-type micromixer are θ ₁ = 45°, θ ₂ = 30°, A = 0.3 mm, B = 0.22 mm, C = 0.3 mm, D = 0.25 mm, and the mixing efficiency can achieve ε _mixing = 0.953 by passing three-unit Tesla-type micromixers (inverse-type, Re = 1, AR = 1). The Tesla-type micromixers designed in this study, which have a lower pressure drop and a higher mixing performance at a low Reynolds number, can contribute to the application of biomedical chips and chemical reactors.