The present invention relates to microfluidic or millifluidic chips (1) comprising at least one pressure sensing unit (4) able to measure a fluid flow pressure. The present invention also relates to a method for a direct and contact-free measuring of a local pressure of a fluid circulating in a microfluidic circuit, using a microfluidic or millifluidic chips (1) according to the invention.

A pressure sensing device for sensing pressure. The pressure sensing device includes a sealed chamber, a second flexible diaphragm, and a protector member. The sealed chamber includes an upper portion comprising a first flexible diaphragm and a lower portion. The protector member includes a bottom surface with a fist concave shape, a top surface with a second concave shape, and a longitudinal hole between a lower cavity and an upper cavity. The lower cavity is between the first flexible diaphragm and a bottom surface of the protector member. The upper cavity is between the second flexible diaphragm and an upper surface of the protector member.

The present invention relates to an apparatus and a method for measuring ground subsidence using a pressure gauge, in which the apparatus includes: a plurality of pressure gauges installed along a ground surface at a subsidence reference point of ground and a plurality of measurement positions to be measured, respectively, to measure a pressure displacement at each of the measurement positions; a pressure transmission pipe filled therein with a liquid supplied from a tank installed at the subsidence reference point to transmit a pressure to each of the pressure gauges; and a measurement terminal connected to each of the pressure gauges through an optical cable, and configured to convert the pressure displacement measured by each of the pressure gauges into a height displacement to measure an amount of the ground subsidence.

The present invention relates to an apparatus and a method for measuring ground subsidence using a pressure gauge, in which the apparatus includes: a plurality of pressure gauges installed along a ground surface at a subsidence reference point of ground and a plurality of measurement positions to be measured, respectively, to measure a pressure displacement at each of the measurement positions; a pressure transmission pipe filled therein with a liquid supplied from a tank installed at the subsidence reference point to transmit a pressure to each of the pressure gauges; and a measurement terminal connected to each of the pressure gauges through an optical cable, and configured to convert the pressure displacement measured by each of the pressure gauges into a height displacement to measure an amount of the ground subsidence.

A micro-machined optical pressure sensor, comprising: a diaphragm configured to deform when a force is applied thereto; and a sensing micro-ring spaced apart from the diaphragm by a gap, the gap being variable depending on the force applied on the diaphragm, wherein the sensing micro-ring is configured to produce a resonance wavelength shift when the gap is varied, the resonance wavelength shift indicative of the force applied to the diaphragm.

A leakage detection device for detecting water leakage in a water pipe of a water system after a stop valve of the water system is closed. The leakage detection device may be part of a stop valve, and may include an interior chamber connectable to the water pipe in such a way so as to receive a stagnation volume of the water when the water flow through the water pipe is stopped by the stop valve. An actuation element provides a force acting on a diaphragm or a piston in the direction of the first interior chamber and against or into the stagnation volume of water. If water leakage is present in the water pipe, the diaphragm or piston will move under the applied force to compensate for the leakage in the water pipe. A sensor unit may detect water leakage in the water pipe based on the movement.

A waveguide for guiding an electro-magnetic wave comprises: a first waveguide part; and a second waveguide part; wherein the first waveguide part has a first width in a first direction (Y) perpendicular to the direction of propagation of the electro-magnetic wave and the second waveguide part has a second width in the first direction (Y), wherein the second width is larger than the first width; and wherein the first and the second waveguide parts are spaced apart by a gap in a second direction (Z) perpendicular to the first and second planes in which the waveguide parts are formed, wherein the gap has a size which is sufficiently small such that the first and second waveguide parts unitely form a single waveguide for guiding the electro-magnetic wave. The waveguide may be used in numerous applications, such as in a photonic integrated circuit, in a sensor or in an actuator.

A pressure sensing device for sensing pressure. The pressure sensing device includes a sealed chamber, a second flexible diaphragm, and a protector member. The sealed chamber includes an upper portion comprising a first flexible diaphragm and a lower portion. The protector member includes a bottom surface with a fist concave shape, a top surface with a second concave shape, and a longitudinal hole between a lower cavity and an upper cavity. The lower cavity is between the first flexible diaphragm and a bottom surface of the protector member. The upper cavity is between the second flexible diaphragm and an upper surface of the protector member.

A sensor comprises: a thin structure, which is configured to receive a force for deforming a shape of the thin structure and which is arranged above a substrate; and a waveguide for guiding an electro-magnetic wave comprising: a first waveguide part; and a second waveguide part; wherein the second waveguide part has a larger width than the first waveguide part; and wherein the first and the second waveguide parts are spaced apart by a gap which is sufficiently small such that the first and second waveguide parts unitely form a single waveguide, wherein one of the first and the second waveguide part is arranged at least partly on the thin structure and another of the first and the second waveguide part is arranged on the substrate.

A pressure sensor includes a lidless structure defining an internal chamber for a sealed environment and presenting an aperture; a chip including a membrane deformable on the basis of external pressure, the chip being mounted outside the lidless structure in correspondence to the aperture so that the membrane closes the sealed environment; and a circuitry configured to provide a pressure measurement information based on the deformation of the membrane.