16 results about "Mode field diameter" patented technology

A multicore optical fiber may include a common cladding comprising a radius R4 defining a glass portion of the optical fiber and having a cladding relative refractive index Δ4. At least two waveguides may extend through the common cladding. Each waveguide may include a core region, an inner cladding region, and a depressed cladding region. Each core region may include a maximum relative refractive index Δ1max. Each inner cladding region may include a relative refractive index Δ2. Each depressed cladding region may include a minimum relative refractive index Δ3min and a trench volume from 20-45%µm2 such that Δ1max>Δ2>Δ3min, and Δ4>Δ3min. A cable cutoff wavelength of each waveguide is ≤1150 nm. The co-propagating and counter-propagating inter-waveguide cross talk between each waveguide and a nearest waveguide is <-35 dB at 1310 nm and <-20 dB at 1550 nm for application lengths of 20 m. A mode field diameter of each waveguide is 8.2-9.0 µm at 1310 nm.

A polarization maintaining optical fiber (1) has: a core (11); an inner layer (12) that surrounds the core (11) without a gap; a pair of stress applying portions (13) disposed at positions sandwiching the core (11); and a cladding (14) that encloses the inner layer (12) and the pair of stress applying portions (13), a mode field diameter of light of a wavelength of 1.55 μm is 9.3 μm or less in a case where the light propagates in the core (11), a cutoff wavelength is 1.32 μm or more in a case where the optical fiber length is 0.25 m and the stress applying portions (13) are wound one turn around an axis having a radius of 2 mm in a manner that a slow axis of the stress applying portions (13) is perpendicular to a surface of the axis, and a product of an area of a cross section of the inner layer (12) perpendicular to a length direction and an average of relative refractive index differences of the inner layer (12) as a whole with respect to the cladding (14) is -36% μm 2 or more and 0% μm 2 or less.

The application discloses an optical fiber device, a preparation method of the optical fiber device and a coupling device, and belongs to the technical field of micro-nano photonics. The application sequentially arranges a mode field expansion area and a phase modulation area at an exit end of an optical fiber, uses the mode field expansion area to expand a beam mode field diameter, uses a substrate film matched with the mode field expansion area in refractive index and a micro-nano unit with high refractive index to form the phase modulation area, realizes a target phase distribution based on geometric sizes and / or a rotation angle of the micro-nano unit, and then performs phase modulation and wavefront shaping on the expanded beam, so as to output a target light field such as a focused beam, a collimated beam, a Bessel beam or a Bessel beam array. The optical fiber device can realize high coupling efficiency, high alignment tolerance and multi-functional wavefront regulation at the exit end of the optical fiber, can solve the mode field mismatch problem in optical fiber-chip coupling, can reduce system complexity and realize multi-functional integration.

This invention relates to a single-mode optical fiber supporting fiber-to-chip interconnect applications, comprising a core layer and a cladding layer, wherein the core layer R1 has a radius of 4.2–6.2 μm, and Δ n The cladding thickness ranges from 0.25% to 0.4%, and from the inside out, it consists of an inner cladding, a first planarization layer, a first depressed cladding, a second planarization layer, a second depressed cladding, and an outer cladding. The radius of the inner cladding, R2, is 5.6–9 μm, and Δn2 decreases linearly. The radius of the first planarization layer, R3, is 8.1–9.2 μm, and Δn2 decreases linearly. n 3 is -0.05% to 0.05%, the radius of the first indented blanket R4 is 18.8 to 28.4 μm, Δ n 4 is -0.95% to -0.55%, the radius R5 of the second flattening layer is 24.2 to 29.2 μm, Δ n 5 is -0.05% to 0.05%, the radius of the second indented blanket R6 is 35 to 50 μm, Δ n The 6-value is -0.50% to -0.75%, and the outer cladding layer is a pure silica glass layer. This invention has a low cutoff wavelength, a large mode field diameter, and good bending performance in short-distance applications.

A waveguide structure (400), a silicon optical chip, a detection apparatus (1500), and a terminal device, used for reducing transmission loss caused by a TPA effect in waveguides under high optical power. The waveguide structure (400) comprises an edge coupler (EC) (4111), a first waveguide (4112), and a second waveguide (4113); the first waveguide (4112) is connected to a first output end of the EC (4111); the second waveguide (4113) is connected to a second output end of the EC (4111); an input end of the EC (4111) has a first mode field diameter; the first waveguide (4112) and the second waveguide (4113) each have a second mode field diameter; and the first mode field diameter is greater than the second mode field diameter. An input of the EC (4111) is a large mode field diameter, and outputs of the EC (4111) are two small mode field diameters. The EC (4111) can directly split an input optical signal into two waveguides, so that the optical power in each waveguide is reduced, high optical power density is not prone to occurring in each waveguide, and thus a TPA effect is not prone to occurring, thereby solving the problem of large transmission loss caused by the TPA effect in waveguides under high optical power density.

This invention discloses a coupling structure and method for an anti-resonant hollow fiber and a single-mode fiber, belonging to the field of fiber coupling technology. The technical solution is as follows: a coupling structure for an anti-resonant hollow fiber and a single-mode fiber, characterized by comprising a broadband light source, a first single-mode fiber, an anti-resonant hollow fiber, a tapered coreless fiber, a tapered single-mode fiber, a second single-mode fiber, and a spectrometer. The beneficial effect of this invention is that by adjusting the parameters of the tapered coreless fiber, the light emitted from the anti-resonant hollow fiber is focused into the tapered single-mode fiber, thereby achieving mode field diameter matching between the single-mode fiber and the anti-resonant hollow fiber. Simulation and experimental results show that, compared to the traditional coupling of a tapered single-mode fiber and an anti-resonant hollow fiber, fusing a tapered coreless fiber at the tip of the tapered single-mode fiber significantly improves the coupling efficiency.

The application discloses a thin-film lithium niobate hetero-integrated double-layer mode spot converter, which comprises a lower lithium niobate waveguide module and an upper silicon nitride waveguide module, the lower lithium niobate waveguide module and the upper silicon nitride waveguide module are positioned by a silicon oxynitride cladding layer, the upper silicon nitride waveguide module is suspended in the silicon oxynitride cladding layer and the suspension height is greater than the thickness of the lower lithium niobate waveguide module, and the silicon oxynitride cladding layer is arranged above a silicon oxide substrate; the lower lithium niobate waveguide module is designed by gradually changing the waveguide width, thereby realizing efficient conversion from a fiber mode to a lithium niobate ridge waveguide base mode; and the upper silicon nitride waveguide module realizes low-loss mode conversion between lithium niobate-silicon nitride hetero waveguides by a three-dimensional reverse taper coupling structure. The double-layer mode spot converter realizes optical field coupling between hetero materials by a vertical stacking structure of a thin-film lithium niobate ridge waveguide and a suspended silicon nitride strip waveguide, and in combination with a lithium niobate ridge waveguide width modulation technology, continuous regulation and control of a mode field diameter can be effectively realized.

A fiber laser device includes a first optical fiber, a second optical fiber, and a third optical fiber configured by polarization maintaining fibers. The first optical fiber includes at least one first part and at least two second parts alternatively disposed with the first part. The first part and the second part adjacent to each other are connected to each other such that a fast axis of the first part coincides with a slow axis of the second part at a connection point. A total length of the first part is equal to a total length of the second parts. A mode field diameter of the first optical fiber is smaller than each of a mode field diameter of the second optical fiber and a mode field diameter of the third optical fiber.

This invention relates to the field of laser measurement instrument technology and discloses an automatic loss detection method for fiber optic connectors based on optical signal attenuation analysis. The method includes: acquiring the backscattered light power sequence of the fiber optic link under test; calculating the logarithmic rate of change of power behind the connector feature point to generate a logarithmic power attenuation rate sequence; processing the sequence through a sliding window to calculate the spatial autocorrelation coefficient and determine a stationarity discrimination index characterizing the evolution trend of mode distribution; identifying the spatial location where the index enters the noise baseline range and establishing the mode equilibrium inflection point; and based on the power evolution relationship between the inflection point and the feature point, stripping the power fluctuation component caused by mode field diameter mismatch and calculating the intrinsic insertion loss. This invention achieves deep decoupling of energy transient fluctuations caused by mode reconstruction and interface intrinsic loss in the spatial dimension, eliminating pseudo-loss interference generated by heterogeneous fiber interconnects.

A power splitter may include a single-core optical fiber, a beam-splitting optical fiber, and a multicore optical fiber. The beam-splitting optical fiber may include a polygonal core configured to output a multimode interference beam pattern including a plurality of beam spots, an input end coupled to the single-core optical fiber, and an output end coupled to the multicore optical fiber. In embodiments, a difference between a mode field diameter of the cores of the multicore optical fiber and a mode field diameter of the core of the single-core optical fiber may be less than or equal to 50%. In embodiments, when the power splitter is in operation, a difference between a distance between neighboring beam spots of the multimode interference beam pattern output by the beam-splitting optical fiber and a core pitch of the cores of the multicore optical fiber may be less than or equal to 10%.

The present invention relates to an optical fiber (200) having a core (202) extending along a central axis (206) and a cladding (204) concentrically surrounding the core (202). The core (202) has at least 83-mole percent (mol %) of Silicon dioxide (SiO2) and at most 17-mole percent (mol %) of an up-dopant and, the cladding (204) has at least 99-mole percent (mol %) of Silicon dioxide (SiO2). Further, the optical fiber (200) has (i) an effective area of greater than or equal to 100 μm2, (ii) a mode field diameter (MFD) in a range of 11 μm to 15 μm, and (iii) a chromatic dispersion of less than or equal to 23.5 picoseconds (ps / (Km·nm) at a wavelength of 1550 nm.

An optical fiber comprising: a core having an outer radius r1; a cladding having an outer radius r4<45 microns; a primary coating surrounding the cladding and having an outer radius r5 and a thickness tp>8 microns, the primary coating having in situ modulus EP of 0.35 MPa or less and a spring constant χP<1.6 MPa, where χP=2EP r4 / tP; and a secondary coating surrounding said primary coating, the secondary coating having an outer radius r6, a thickness tS=r6−r5, in situ modulus ES of 1200 MPa or greater, wherein >10 microns and r6≤85 microns. The fiber has a mode field diameter MFD greater than 8.2 microns at 1310 nm; a cutoff wavelength of less than 1310 nm; and a bend loss at a wavelength of 1550 nm, when wrapped around a mandrel having a diameter of 10 mm, of less than 1.0 dB / turn.

A multicore optical fiber may include a common cladding comprising a radius R4 defining a glass portion of the optical fiber and having a cladding relative refractive index Δ4. At least two waveguides may extend through the common cladding. Each waveguide may include a core region, an inner cladding region, and a depressed cladding region. Each core region may include a maximum relative refractive index Δ1max. Each inner cladding region may include a relative refractive index Δ2. Each depressed cladding region may include a minimum relative refractive index Δ3min and a trench volume from 20-45% μm2 such that Δ1max>Δ2>Δ3min, and Δ4>Δ3min. A cable cutoff wavelength of each waveguide is ≤1150 nm. The co-propagating and counter-propagating inter-waveguide cross talk between each waveguide and a nearest waveguide is <−35 dB at 1310 nm and <−20 dB at 1550 nm for application lengths of 20 m. A mode field diameter of each waveguide is 8.2-9.0 μm at 1310 nm.

The present invention relates to optical coupling between optical components and, more particular, to an optical probe (1) configured for optical testing of at least one micro-optical component (50), to a method for producing an optical probe (1), and to a method for simultaneously optical testing of at least one micro-optical component (50). The optical probe (1) is comprising: a probe head (10), wherein the probe head (10) comprises a test component (2); a plurality of micro-optical elements (20), wherein each micro-optical element (20) is a separate element with regard to the test component (2) and in mechanical contact with the test component (2), wherein each micro-optical element (20) is individually aligned with regard to the test component (2); and wherein each micro-optical element (20) is configured to generate a mode-field diameter of up to 100 µm, wherein the micro-optical elements (20) are configured to optically couple at least one light beam (3) between the test component (2) and the micro-optical component (50), thereby being configured to determine an emission characteristics of a coupling location (52) comprised by the micro-optical component (50), wherein the micro-optical component (50) further comprises a beam-shaping element (51a), wherein the beam-shaping element (51a) is arranged in a manner that at least a portion of the light beam (3) is travelling through the beam-shaping element (51a).

This optical fiber comprises: a glass fiber having a core, an inner cladding surrounding the core, and an outer cladding surrounding the inner cladding; and a covering resin layer covering the outer periphery of the glass fiber. The core contains germanium. When the diameter of the core is 2r1 and the diameter of the inner cladding is 2r2, 3 ≤ r2 / r1 ≤ 6 holds. The diameter of the core is 4.6-8.9 μm inclusive. When the relative refractive index difference of the core is ∆1, the relative refractive index difference of the inner cladding is ∆2, and the relative refractive index difference of the outer cladding is ∆3, 0.40% ≤ ∆1−∆2 ≤ 0.80% and −0.10% ≤ ∆2−∆3 ≤ 0.10% hold. Residual stress in the core is compressive stress. The mode field diameter at a wavelength of 1310 nm is 8.4 μm or less. The cable cutoff wavelength is less than 1530 nm. The diameter of the covering resin layer is 180 μm or less.