The present invention discloses a two-dimensional optical waveguide pressure sensor array comprising two or more row optical waveguides; two or more column optical waveguides, wherein the row optical waveguides and the column optical waveguides are deformable and arranged in a planar array to define a sensor in the crosspoints, wherein each crosspoint includes one of the row waveguides in contact with one of the column waveguides at its intersection point; wherein each crosspoint further includes a light coupling structure configured to enhance waveguide bending when pressure is applied to the crosspoint; wherein the light coupling structure comprises a layer of mechanical light scattering material disposed in contact with at least one of the row or column optical waveguide; or wherein the optical waveguide pressure sensor array can sense pressure by providing light to the row optical waveguides and measuring light coupled at each crosspoint to its column optical waveguide.

The present invention discloses a distributed continuous high-accuracy bidirectional displacement fiber-optic measurement system and a measurement method thereof for measuring displacement of a measurement target, including a Brillouin analysis device connected with an optical fiber strain gauge, a fiber-optic sensor assembly including a reference fiber-optic sensor device and a plurality of fiber-optic sensor devices, and an operation module, the operation module is operable to receive the continuous data and the single-spot data transmitted from the Brillouin analysis device and the fiber-optic sensor devices, and to calculate an accurate displacement for each interval of the optical fiber strain gauge according to the continuous data and the single-spot data so as to form continuous displacement data. Thus, the present invention is economic in respect of cost and suits the need of the market application, and can be applied in a large area, and enhances the accuracy of measurement.

An optical sensor according to an embodiment of the present disclosure includes a light emitting substrate and a circuit board. The light emitting substrate includes a light emitting device. The circuit board is provided at a position opposing the light emitting device. The circuit board includes a light transmitting section and one or multiple light receiving devices. The light transmitting section transmits light of the light emitting device. The one or multiple light receiving devices receive light reflected by a reflective layer of the light of the light emitting device exiting through the light transmitting section. For example, the one or multiple light receiving devices are formed on a first major surface of the circuit board. For example, the light emitting substrate is disposed at a position opposing a second major surface, of the circuit board, on an opposite side to the first major surface, and is stacked on the circuit board with a first bump interposed therebetween.

A system for assaying forces applied by cells includes an optically transparent substrate comprising a soft material having a Young's modulus within the range of about 3 kPa to about 100 kPa. An array of molecular patterns is disposed on a surface of the optically transparent substrate, the molecular patterns include fluorophore-conjugated patterns adherent to cells. The system includes at least one light source configured to excite the fluorophore-conjugated patterns and an imaging device configured to capture fluorescent light emitted from the fluorophore-conjugated patterns. Dimensional changes in the size of the patterns are used to determine contractile forces imparted by cells located on the patterns.

Provided is a displacement measurement system including: a sensor that is contactable with a measurement target object and includes a first spacer that has at least a one-dimensional spread, and two or more types of light emitting particles that are distributed over the spread of the first spacer and emit light at different wavelengths by an excitation energy; an excitation energy source that causes the two or more types of light emitting particles included in the sensor to emit light; and a light receiver that receives light emitted from the sensor.

This application describes a fibre optic cable structure which is advantageous for distributed fibre optic sensing, for example distributed acoustic sensing (DAS). The fibre optic cable structure includes an optical fibre for distributed fibre optic sensing and is configured to comprise at least one longitudinal section of a first type, which exhibits a change in effective optical path length of the optical fibre of one polarity in response to a given applied force, and which is adjacent to at least one longitudinal section of a second type, which exhibits a change in effective optical path length of the optical fibre of the opposite polarity in response to an equivalent applied force. When used for DAS, the response of a sensing portion that includes sections of both the first and second types, will include or exclude certain wavenumber by summation, which provides a directional sensitivity to incident waves.

A system for monitoring downhole cement quality in a cased well includes an active acoustic source that generates acoustic waves, a distributed acoustic sensor, and a controller. The distributed acoustic sensor includes an optical fiber disposed on an outer surface of a casing of the cased well; a pulsed laser coupled to the optical fiber and that transmits pulses of laser light along the optical fiber; a sensor that detects light that is backscattered and reflected by the optical fiber; and a processor that controls the pulsed laser, receives signals from the sensor, and converts the signals into acoustic information. The controller receives the acoustic information from the processor and identifies well integrity loss.

Various tactile sensors and associated methods are enabled. For instance, a sensing apparatus comprises a photosensitive sensor. A compound-eye structure is on the photosensitive sensor and an elastomer layer is on the compound-eye structure. A reflective layer is on the elastomer layer, opposite the compound-eye structure and a light source emits light between the reflective layer and the compound-eye structure.

The disclosure relates to an impact detection composite as well as related articles and methods. The impact detection composite incorporates a plasticizer and plurality of microcapsules into a polymeric matrix. The microcapsules serve as a means for detecting impact on the composite or a substrate to which it is attached. A sufficiently forceful impact can rupture the microcapsules and release an indicator therein. Presence of the plasticizer in the matrix facilitates diffusion of the indicator through the matrix once released. This allows for rapid detection of the indicator, for example as a visually observable color or color change at an external surface of the impact detection composite. The detectable change provides a tamper-proof and non-electronic means for detecting an impact. The impact detection composites can be incorporated into a variety of articles and used in a variety of settings, for example to monitor personal safety, to monitor article integrity, etc.

In an example, a pressure indicator film includes a first polymeric film material and a second polymeric film material that satisfy a threshold thermal degradation temperature. The pressure indicator film includes microcapsules on a surface of the first polymeric film material and a developer material on a surface of the second polymeric film material. The microcapsules are formed from a polymeric shell material that satisfies the threshold thermal degradation temperature. The microcapsules encapsulate a payload that includes a pH indicator and a solvent having a boiling point that is greater than the threshold thermal degradation temperature.