Sensing Method and Sensor System A sensing method comprises using a vertical cavity surface emitting laser (VCSEL) to oscillate and emit a laser beam. A diaphragm is used to reflect a portion of the laser beam back into the VCSEL. This method can be referred as self mixing interferometry. A current or voltage at the VCSEL is monitored, and is used to sense movement of the diaphragm. This allows a property external to the VCSEL to be sensed without using a photo-detector.

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 fiber optic sensor and a related method of manufacture are provided. The fiber optic sensor includes an embedded optical fiber contained within a metal diaphragm assembly, where the terminal end of the optical fiber is positioned opposite a diaphragm. The method includes forming a metal-embedded optical fiber by ultrasonic additive manufacturing and securing the metal-embedded optical fiber to a housing having a diaphragm that is opposite of the terminal end of the optical fiber. The sensor can provide extremely accurate pressure measurement at high temperatures and in highly corrosive media. An optical fiber-based pressure sensing system is also provided.

Systems and methods for calibrating deformable sensors are disclosed. In one embodiment, a method of calibrating a deformable sensor includes capturing image data of the deformable sensor using an external image sensor, wherein the deformable sensor comprises a deformable membrane defining an enclosure that is configured to be filled with a medium. The method further includes comparing the image data of the deformable sensor to a metric. When the image data does not satisfy the metric, the method includes adjusting a pressure within the enclosure.

A method includes receiving wavelength domain data for a time step, performing a Discrete Fourier Transform (DFT) to transform the wavelength domain data for the time step into frequency domain data for the time step only for the limited set of frequency bins associated with a frequency of interest, calculating pressure based on the frequency domain data for the time step, and updating the frequency of interest and the limited set of frequency bins. The method includes repeating receiving wavelength data for subsequent time steps, performing a DFT to transform the wavelength data for the respective subsequent time steps, calculating pressure for each subsequent time step, and updating the frequency of interest and limited set of frequency bins for each subsequent time step. The method includes outputting pressure data based on calculating pressure for the subsequent time steps.

A pressure sensor (100) for a measuring system (10) measuring concentrations of gaseous and/or aerosol components of a gas mixture with a reaction carrier (14), with a flow channel (42). The flow channel (42) forms a reaction chamber (46) with a reactant (48), that enters into an optically detectable reaction, and with a measuring device (12) with a gas port unit (5) connecting an inlet channel (16) and an outlet channel (18) to the flow channel (42) and a gas delivery unit (28). The pressure sensor (100) measures a pressure difference of a gas mixture flowing through the gas delivery assembly unit (2) and/or the flow channel (42) of the reaction carrier (14) and has an elastic element (102), which is configured to undergo deformation as a function of the pressure difference. A measuring method, a measuring device and a reaction carrier for such a measuring system are also provided.

Optical pressure sensor assemblies that can be used with existing catheters and imaging systems. Pressure sensors may be compatible with atherectomy and occlusion-crossing catheters, where intravascular pressure measurements at various vessel locations are needed to determine treatment efficacy. The pressure sensors may employ an optical pressure measurement mechanism using optical interferometry, and may be integrated with existing imaging modalities such as OCT. The pressure sensor assemblies may include a movable membrane that deflects in response to intravascular pressure; an optical fiber that transmits light to the movable membrane and receives light reflected or scattered back from the movable membrane into the fiber; and a processor or controller configured to determine the distance traveled by the light received in the fiber from the movable membrane, where the distance traveled is proportional to the intravascular pressure exerted against the membrane.

An integrated optical transducer for measuring displacement of a diaphragm comprises the diaphragm, a lens element and a substrate body having a waveguide structure and a coupling element. The diaphragm is arranged distant from the substrate body and substantially parallel to a main extension plane of the substrate body. The waveguide structure is configured to guide light from a light source to the coupling element and from the coupling element to a photodetector . The coupling element is configured to couple at least part of the light in the waveguide structure onto a light path between the coupling element and the diaphragm and to couple light reflected by a surface of the diaphragm from the light path into the waveguide structure. The lens element is arranged on the light path such that light on the light path passes through the lens element.

An integrated optical transducer for detecting dynamic pressure changes comprises a micro-electro-mechanical system, MEMS, die having a MEMS diaphragm with a first side exposed to the dynamic pressure changes and a second side, and an application-specific integrated circuit, ASIC, die having an optical interferometer assembly. The interferometer assembly comprises a beam splitting element for receiving a source beam from a light source and for splitting the source beam into a probe beam in a first beam path and a reference beam in a second beam path, a beam combining element for combining the probe beam with the reference beam to a superposition beam, and a detector configured to generate an electronic interference signal depending on the superposition beam. The MEMS die is arranged with respect to the ASIC die such that a gap is formed between the second side of the diaphragm and the ASIC die, with the gap defining a cavity and having a gap height. The first beam path of the probe beam comprises coupling into the cavity, reflection off of a deflection point or a deflection surface (16) of the diaphragm and coupling out of the cavity.

Optical pressure sensor assemblies that can be used with existing catheters and imaging systems. Pressure sensors may be compatible with atherectomy and occlusion-crossing catheters, where intravascular pressure measurements at various vessel locations are needed to determine treatment efficacy. The pressure sensors may employ an optical pressure measurement mechanism using optical interferometry, and may be integrated with existing imaging modalities such as OCT. The pressure sensor assemblies may include a movable membrane that deflects in response to intravascular pressure; an optical fiber that transmits light to the movable membrane and receives light reflected or scattered back from the movable membrane into the fiber; and a processor or controller configured to determine the distance traveled by the light received in the fiber from the movable membrane, where the distance traveled is proportional to the intravascular pressure exerted against the membrane.