An optoelectronic chip includes optical inputs having different passbands, a photonic circuit to be tested, and an optical coupling device configured to couple said inputs to the photonic circuit to be tested.

The invention is directed to the characterization of an optical channel, such as an optical fiber, in an optical network. The method includes calibrating a transmitter by measuring its transmitter and dispersion eye closure (TDEC, in the case of non-return to zero optical (NRZ) optical systems or transmitter and dispersion eye closure quaternary (TDECQ, in the case of 4-level pulse amplitude modulation (PAM4) optical systems). That calibrated transmitter is used to characterize the optical channel being tested by providing a measure of its stressed eye closure (SEC) or stressed eye closure quaternary (SECQ). A loss deficit for the optical channel can be calculated by subtracting the SEC or SECQ value from the maximum TDEC or TDECQ value.

A photonic device and a continuous-wave THz signal generator using such photonic device. The photonic device includes an input waveguide arranged to receive input waves of at least two input frequencies and to generate photons at an output frequency associated with the at least two input frequencies; an output waveguide coupled to the input waveguide and arranged to collect the generated photons at the output frequency; wherein the output waveguide is further arranged to facilitate an amplification of the generated photons as the generated photons propagates along the output waveguide and arranged to output an amplified signal at the output frequency.

The present invention has an object to provide an optical fiber testing method and an optical fiber testing device capable of measuring the delay ratio between the modes at each position of a fiber over a long distance in which a plurality of modes propagate.

An optical fiber testing method and its device according to the present invention, measure the change amount for the wave number k of a Brillouin Frequency Shift ν in stimulated Brillouin scattering generated in the same acoustic mode, with respect to each target propagation mode. Thereby, the ratio of the change amount measured at each propagation mode is acquired as the group delay ratio between the modes.

There is provided a method for measuring the PDL of a DUT as a function of the optical frequency ν within a spectral range, which uses a single wavelength scan over which the input-SOP varies in a continuous manner. The power transmission through the DUT, curve T(ν), is measured during the scan and the PDL is derived from the sideband components of the power transmission curve T(ν) that results from the continuously varying input-SOP. More specifically, the Discrete Fourier Transform (DFT) of the power transmission curve T(ν) is calculated, wherein the DFT shows at least two sidebands. At least two sidebands are extracted and their inverse DFT calculated individually to obtain complex transmissions (ν), =−J . . . J, where J is the number of sidebands on one side. The response vector |m(ν) of the DUT is derived from the complex transmissions (ν) and a matrix determined by the continuous trajectory of the SOP of the input test lightwave; and the PDL of the DUT as a function of ν (PDL curve) is derived therefrom.

An optoelectronic chip includes optical inputs having different passbands, a photonic circuit to be tested, and an optical coupling device configured to couple said inputs to the photonic circuit to be tested.

The present embodiment relates to a method of directly measuring a leakage loss from a peripheral core in a MCF with a coating to the coating. In the measurement method, in a high refractive-index state in which the coating is present on an outer periphery of a common cladding, first transmission power of measurement light, which propagates through the peripheral core of the MCF, is measured. On the other hand, in a low refractive-index state in which a low-refractive-index layer with a lower refractive index than the common cladding is provided on the outer periphery of the common cladding, second transmission power of the measurement light, which propagates through the peripheral core of the MCF, is measured. The leakage loss LL from the peripheral core to the coating is calculated as a difference between the first transmission power and the second transmission power.

A method and system for obtaining photonic parameters. The system includes a computer, an optical source, a first and second optical fiber, a Mach-Zehnder Interferometer (MZI) structure, and a detector. The computer includes a processor and memory. The optical source is constructed to emit light of a first optical mode and a second optical mode in response to an instruction by the computer. The first optical fiber receives the first or second optical mode. The MZI structure includes first and second pluralities MZIs and receives the first or second optical mode from the optical fiber. The second optical fiber receives light from the MZI structure. The detector is configured to receive light that propagated through the second optical fiber, generate image data and provide the image data to the computer. The computer obtains a plurality of photonic parameters based on the image data and initial guesses for the plurality of photonic parameters.

A polarization-related characteristic of an optical path is determined from a predetermined function of the mean-square of a plurality of differences between polarization-analyzed optical power parameters corresponding to pairs of wavelengths mutually spaced about a midpoint wavelength by a small optical frequency difference. At least some of the said differences correspond to wavelength pairs measured under conditions where at least one of midpoint wavelength, input state of polarization (I-SOP) or analyzed state of polarization (A-SOP) of a pair is different.

Using pump-probe measurements on multi-span optical links may result in the determination of one or more of the following: 1) wavelength-dependent power profile and gain evolution along the optical link; 2) wavelength-dependent dispersion map; and 3) location of regions of high polarization-dependent loss (PDL) and polarization-mode dispersion (PMD). Such measurements may be a useful diagnostic for maintenance and upgrade activities on deployed cables as well as for commissioning new cables.