A method for compensating for dynamic changes in a body of a patient during a controlled interaction with the body includes acquiring data from at least one sensing device disposed on the body and detecting a change along at least one optical fiber of the sensing device caused by dynamic changes associated with the body during the controlled interaction. A respiratory gating signal is generated based on the change along the at least one optical fiber of the sensing device measured over time. The method further comprises controlling relative movement between the body and an interactive device in response to the respiratory gating signal to compensate for the dynamic changes associated with the body during the controlled interaction.

A system for sensing phase changes in a medium includes a bidirectional interferometer having a reference arm and a sensing arm, two inputs at each of the two ends of the interferometer, and a circulator disposed between each input and the interferometer. Sources provide squeezed state pulses at an input at each end of the interferometer. Spaced-apart partial reflectors are disposed along the arms. There are detectors associated with each input. The circulators pass the squeezed state pulses into the interferometer and route reflections of the pulses to the detectors. Classical pulses may provided at the other input at each end of the interferometer.

The present invention discloses an integrated system for optical fiber sensing and communication through sharing co-frequency resources. Specifically, the system consists of two parts: optical path detection and circuit demodulation. The entire system consists of a continuous wave laser, a fiber coupler, a polarization controller, a mach-zehnder modulator, an arbitrary waveform generator, an erbium-doped fiber amplifier, an optical filter, an optical fiber annular, an optical fiber, a photodetector, a data acquisition device, a balance detector and a data acquisition card. A transmission optical signal and a sensing detection light are generated by the same laser, transmission performance and sensing performance of the system are changed by adjusting modulation power of a transmission signal, the transmission signal is obtained by using direct detection at far-end, a sensing signal is obtained by using heterodyne coherent detection at local-end. The present invention provides a simple, compact and high-efficiency integrated system for co-frequency sharing optical fiber sensing and communication, to solve the deficiencies of the existing integrated system in practical applications.

A method for compensating for dynamic changes in a body of a patient during a controlled interaction with the body includes acquiring data from at least one sensing device disposed on the body and detecting a change along at least one optical fiber of the sensing device caused by dynamic changes associated with the body during the controlled interaction. A respiratory gating signal is generated based on the change along the at least one optical fiber of the sensing device measured over time. The method further comprises controlling relative movement between the body and an interactive device in response to the respiratory gating signal to compensate for the dynamic changes associated with the body during the controlled interaction.

A distributed acoustic sensing system based on an optical neural network and an all-optical integration method are provided. The distributed acoustic sensing system based on an optical neural network includes: a distributed acoustic sensing (DAS) optical path integrated part, an external connection part, and an integrated signal processing chip. The provided combines an integrated optical delay line, a tri-port analogous detection structure and a pure optical neural network module to achieve all-optical integration of the DAS sensing system and signal processing by a pure optical method, which has the advantages of reducing photoelectric conversion, enhancing parallel processing capabilities, increasing processing speed, reducing energy consumption, improving system stability, and simplifying system architecture.

An object is to provide a differential mode delay measurement device and a method thereof capable of measuring a DMD with a simple configuration even when an FMF to be measured is a long distance.

A differential mode delay measurement device 301 according to the present invention includes a light source 11 configured to output a coherent light beam having an optical frequency changed with a predetermined modulation period, a branching element 12 configured to bifurcate the light beam; a light incidence unit 13 configured to excite one of the light beams in a plurality of modes, cause the one of the light beams to enter one end of an optical fiber to be measured 51 that is a few-mode optical fiber, and input the other of the light beams into one end of a reference optical fiber 52 in a single mode; an image sensor 15 configured to observe an interference light beam between a measurement light beam emitted from the other end of the optical fiber to be measured 51 and a reference light beam emitted from the other end of the reference optical fiber 52; and an arithmetic unit 16 configured to detect a peak of the interference light beam appearing when the modulation period is changed, and measure a differential mode delay based on a period of the peak and an electric field distribution of the interference light beam at the peak.

A method for compensating for dynamic changes in a body of a patient during a controlled interaction with the body includes acquiring data from at least one sensing device disposed on the body and detecting a change along at least one optical fiber of the sensing device caused by dynamic changes associated with the body during the controlled interaction. A respiratory gating signal is generated based on the change along the at least one optical fiber of the sensing device measured over time. The method further comprises controlling relative movement between the body and an interactive device in response to the respiratory gating signal to compensate for the dynamic changes associated with the body during the controlled interaction.

Techniques for determining compensation parameters for a fiber sensor are disclosed herein. An example method includes detecting interferometric pattern data spanning an affected region of the fiber sensor when the fiber sensor is experiencing temperature transitions over the affected region. The example method further includes determining an optical path length parameter and a relative group index parameter that compensate for variations between a target optical configuration of the fiber sensor cores and an actual optical configuration of the fiber sensor cores.

The photo-acoustic conversion based sound emitter device has a sound output surface for transmitting sound wave vibrations to a medium outside the device. An optical waveguide, is used to transmit light through an optical path within the device. First and second photo-acoustic conversion volumes, at different distances from the sound output surface, are used for transmitting sound generated in the first and second volume to the medium via the sound output surface, the optical path extending directly or indirectly successively through the first and second photo-acoustic conversion volume. The device comprises an intermediate volume separating the first and second photo-acoustic conversion volumes along the optical path, the intermediate volume having a lower light absorption coefficient than the first and second photo-acoustic conversion volumes; and/or the first and second photo-acoustic conversion volume have a different cross-section area size and/or shape with virtual planes perpendicular to the optical path; and/or the first and second photo-acoustic conversion volumes have different optical absorption coefficients, or a different optical wavelength dependence of these optical absorption coefficients.