An optical sensor module includes an interferometric sensor and a set of one or more optical elements. The interferometric sensor includes a coherent light source and at least one detector configured to generate an interferometric signal. The set of one or more optical elements is configured to simultaneously direct a first portion of light emitted by the coherent light source toward a first focus area within a first depth of focus; direct a second portion of the light emitted by the coherent light source toward a second focus area within a second depth of focus; and direct portions of the emitted light that are returned from one or more objects within the first depth of focus or the second depth of focus toward the interferometric sensor.

There is described a method of determining a position of a pipeline inspection gauge (PIG) in a fluid conduit. While the PIG is moving through the fluid conduit, one or more sensors positioned along the fluid conduit are used to detect one or more signals. Parameter data is extracted from the detected one or more signals. The parameter data includes one or more parameters of the detected one or more signals as a function of time and position along the fluid conduit. PIG movement data indicative of a position of the PIG in the fluid conduit as a function of time is generated using the parameter data.

Disclosed are method and electronic components for: i) electronically extracting a sequence of values from a measurement signal corresponding to a position of a moving object, wherein the sequence of values indicates the position of the moving object at corresponding time increments; ii) electronically determining at least one of an estimate for a velocity of the moving object and an estimate for an acceleration of the moving the object based on a plurality of the values in the sequence of values; and iii) electronically correcting a value in the sequence of values to substantially reduce the effect of processing and signal delays based on one or both of the velocity and acceleration estimates.

A rotary encoder includes: a rotary disk with an angle code; a light source; a detector reading the angle code; and a processing unit acquiring a reading value. The light source includes at least two light-emitting elements spaced from each other. Every time the rotary disk is rotated by a predetermined angle, where an arbitrary angle from a rotation angle θ within a reading range on the detector is provided as φ, the processing unit acquires reading values f.sub.I(θ+φ) and f.sub.I(θ) with a first light-emitting element and a reading value f.sub.II(θ+φ) with a second light-emitting element, to calculate a reading value error due to deflection at an angle θ+φ based on the difference between the reading values f.sub.II(θ+φ) and f.sub.I(θ+φ), to obtain a difference g.sub.I(θ,φ) between the reading values f.sub.I(θ+φ) and f.sub.I(θ) such that the error is reflected, and to self-calibrate based on a change in the difference g.sub.I(θ,φ).

A system for measuring pressure, temperature or both includes a diaphragm that responds to a change in temperature or pressure, and a base connected to the diaphragm that has a sapphire element. Between the diaphragm and the base is a cavity. An optical fiber that conducts light reflected off of a surface of the diaphragm is adjacent the cavity. An interrogator is used for detecting a deflection of the diaphragm based on at least two reflected light signals having similar wavelengths and coherence lengths. A quadrature phase detection unit demodulates signals received by the interrogator.

Provided are a multi-wavelength photoelectric measurement device, a confocal measurement device, an interference measurement device, and a color measurement device capable of measuring the characteristic amount of a measurement object such as the thickness, distance, displacement, or color with high accuracy using multi-wavelength light such as white light. The multi-wavelength photoelectric measurement device includes a laser light source, a light source optical member for concentrating light from the laser light source, a phosphor excited by light concentrated by the light source optical member, an optical fiber unit that includes one or a plurality of optical fibers and the phosphor disposed on a first end, receives light emitted by the phosphor from the first end, and transmits the received light toward a second end, and a head optical member that concentrates light emitted from the second end of the optical fiber unit toward a measurement object.

There is provided retro-reflective interferometer device for detection and/or measurement of displacements and/or rotations and/or mechanical vibrations, the device includes a transceiver unit including at least one radiation source capable of emitting a radiation beam and at least one radiation receiver; a movable unit movably mounted with respect to said transceiver unit, the movable unit includes one or more movable elements that are susceptible to displacement and/or vibration by an external force; and at least one retro-reflective element capable of reflecting back the radiation beam to form a sequence of radiation patterns; and an analyzing element operationally associated with the radiation receiver for analyzing a displacement change, an intensity change and/or a frequency change in the sequence of radiation patterns. Further provided are systems including the device and methods utilizing the same.

A fiber-optic sensors for measuring deformation, intended to operate in a harsh environment is provided. The sensor comprises a Fabry-Perot-cavity-based optical measurement head, a linking optical fiber and an expansion reserve case, the case comprising a segment of the linking optical fiber. The inside thickness of the case is comprised between one and several millimeters, the case being flat and of shape referred to as bicorne shape, the shape comprising a convex central portion and two concave symmetric ends, the optical fiber forming, inside the bicorne, one and only one arch, the segment of the optical fiber being, in addition, tangent to the internal surfaces of the reserve case, whatever the temperature conditions.

An electronic watch may include a housing and a crown configured to receive a rotational input. The crown may include a knob external to the housing, a rotor coupled to the knob and configured to rotate in response to the rotational input, the rotor defining a recess extending about a circumference of the rotor, and a coating positioned in the recess and configured to reflect at least a portion of light incident on the coating. The electronic watch may further include an optical sensing system configured to detect the rotational input using the reflected portion of the light.

The invention pertains to a contactless measurement method for detecting rotation of an object over an axis coinciding with an optical axis of a probe beam. The probe beam is comprised of two monochromatic wavelengths with circular polarizations of opposite chirality, having a frequency difference for providing a heterodyne probe beam. A neutral beam splitter is provided that directs a reflected beam via a polarizer filter towards a first photodetector and that directs a transmitted beam toward a quarter wave plate attached to a rotatable object. A mirror reflects the probe beam, via the same quarter wave plate, back into the neutral beam splitter, which directs the reflected beam via a polarizer filter toward a second photodetector. The rotation is derived from the relative phase difference between the first and second photodetector signals.