A displacement sensor has a graded index multi-mode fiber with a length that is an odd multiple of a quarter pitch length of the graded index multi-mode fiber and a single-mode optical fiber fusion spliced to the first end of said graded index multi-mode fiber. A reflective mirror coating is applied to a planar facet on the second end of said graded index multi-mode fiber. A plurality of mechanical attachments are spaced along the graded index multi-mode fiber and single-mode optical fiber that mechanically deform said graded index multi-mode fiber, when any one of said plurality of mechanical attachments is displaced relative to any other one of said plurality of mechanical attachments.

A method of detecting tampering with a conveyance medium may include determining a baseline brightness level detected at opposing ends of an optical fiber segment disposed proximate to the conveyance medium, determining whether a change in brightness above a threshold level occurs, and providing an output indicating that a breach in continuity of a shielding material that shields both the conveyance medium and the optical fiber segment from exposure to ambient light has occurred in response to the change in brightness being above the threshold level.

Waveguides, such as light guides, made entirely of elastomeric material or with indents on an outer surface are disclosed. These improved waveguides can be used in sensors, soft robotics, or displays. For example, the waveguides can be used in a strain sensor, a curvature sensor, or a force sensor. In an instance, the waveguide can be used in a hand prosthetic. Sensors that use the disclosed waveguides and methods of manufacturing waveguides also are disclosed.

A side illuminated multi point multi parameter optical fiber sensor that requires no sensitive coating is provided. This sensor comprises an optical fiber having at least one removed cladding section as the sensitive region, at least one probing light source that side illuminates the fiber, a power supply, a detector, a signal processor and a display. The sensitive optical fiber is optically affected by the presence of a measurand medium that can fluoresce, phosphoresce, absorb and/or scatter the probing light. This probing light is guided by the fiber core towards a detector which measures the light intensity and this light intensity is correlated with a measurand.

What are disclosed are a flexible display device and a method of detecting a curved state of a flexible display panel thereof, which can estimate a curved state of a flexible display panel. The flexible display device includes a flexible display panel and a controller. The flexible display panel includes N optical fibers which can be curved with the curving of the flexible display panel, a laser transmitter disposed at an input terminal of the optical fiber and a light intensity detector disposed at an output terminal of the optical fiber, wherein N is an integer greater than or equal to 1. The controller is configured to acquire a light intensity parameter detected by the light intensity detector, and determine a current state of the flexible display panel according to the light intensity parameter, wherein M is an integer greater than or equal to 1 and smaller than or equal to N.

A fiber optic sensor for detecting an excitation in proximity to a fiber optic assembly, the excitation inducing a modulation of the phase of an optical signal propagating in the fiber optic assembly, the sensor comprises: a laser assembly emitting at least one laser beam; a fiber optic assembly; an optical system configured to: inject at least one portion of the laser beam; generate at least one laser signal beam issued from the laser beam injected into and propagated in the fiber assembly; generate at least one reference beam from the laser beam or the signal beam; produce at least one interference zone corresponding to the interference between a portion of the reference beam and a portion of the interference signal beam corresponding to the interference between a portion of the reference beam and a portion of the signal beam; a digital holography assembly comprising: a liquid-crystal spatial light modulator; a video camera configured to receive the interference zone and to transcribe it electrically to the liquid-crystal spatial light modulator in order to create thereon a phase hologram corresponding thereto; at least one optical detector configured to detect an output optical signal beam.

A photoelectric sensor includes a connecting section for light projection to which a light propagation member for light projection optically coupled to a light emitting element is connected, a connecting section for light reception to which a light propagation member for light reception optically coupled to the light receiving element is connected, a signal generating unit configured to compare a light reception signal generated by the light receiving element and a threshold and generate a detection signal indicating a result of the comparison, a first light emitting element for indication optically coupled to the connecting section for light reception, and a mounting substrate on which each of the first light emitting element for indication and the light receiving element is positioned in the connecting section for light reception or one of the first light emitting element for indication and the light receiving element is positioned via the other.

A side illuminated multi point multi parameter optical fiber sensor that requires no sensitive coating is provided. This sensor comprises an optical fiber having at least one removed cladding section as the sensitive region, at least one probing light source that side illuminates the fiber, a power supply, a detector, a signal processor and a display. The sensitive optical fiber is optically affected by the presence of a measurand medium that can fluoresce, phosphoresce, absorb and/or scatter the probing light. This probing light is guided by the fiber core towards a detector which measures the light intensity and this light intensity is correlated with a measurand.

A system and method of delivering fiber optic communication service is provided. The method includes monitoring a strain signal generated by a strain-sensing optical fiber embedded in a roadway. The method includes comparing the strain signal to a predetermined allowable strain threshold of an optical communication cable associated with the strain-sensing optical fiber. The method includes relieving strain at a position along a length of the optical communications cable when the strain signal is determined to exceed the predetermined allowable strain threshold.

The invention relates to a light conductor for sensory purposes, comprising at least one crack, wherein a longitudinal direction of the crack relative to a direction of propagation of the light conductor includes an angle of incidence (), and wherein the crack is delimited by two boundary surfaces, each of which is substantially parallel to the longitudinal direction of the crack, the two boundary surfaces including an opening angle (), said opening angle () being greater than 0.