Multicore Optical Fiber Research Articles

Insertion Success or Failure Distinction for Miniature Assembling Automation of the Optical Parts

Assembling for miniature mechanism is used in the precision mechanics and the electronics generally. An optical fiber array is an optical communication device that consists of multi-core optical fibers and the V-grooved substrate. Because the demand for optical fiber arrays has increased, it needs the mass production of optical fiber arrays. For automatic assembling of optical fiber array, a fiber must be put in a precise position of the V-groove. In the fiber insertion to the V-grooved substrate, the trial fiber insertion system distinguished success or failure of fiber insertion using image application. The failure of the insertion depends on a bent fiber or an adsorption of the fiber. Then the system replaces a bending and an adsorption by the lateral offset and the angular offset. The system measures them with micro CCD from two directions. The effectiveness of this new distinction system was verified with 12 cores fibers.

Multicore Optical Fibres for an External Talbot Cavity

In the paper the application of multicore optical fibres in phased-locked high power lasers is presented. The manufacturing and properties of multicore active optical fibres were presented. The thermally stable aluminosilicate glass doped with Nd (0.5 mol%) ions were melted and used as cores in manufactured multicore optical fibres. Two configurations of double clad multicore optical fibres with the circular array containing 15 and 30 Nd doped cores on ring inside a large pump clad were realized. Absorption and luminescence spectra of obtained glasses and fibres were presented. An external plane mirror located at certain distance of the array forms the basic Talbot cavity. The possibilities of mode selection and phase-locking by using Talbot resonator applied to fabricated multicore fibres were investigated.

Design and Fabrication of an Er-Doped Silica Optical Fiber with Six Photosensitive Subcores

A type of multi-core Er-doped photosensitive silica optical fiber (MC-EDPF) is proposed and fabricated, in which a high consistency Er-doped core is surrounded by six high consistency Ge-doped cores. The multi-core design can overcome the difficulties encountered in the design and fabrication of single-core EDPFs through a modified chemical vapor deposition method combined with solution doping technology, and there is a conflict between high consistency Er doping and high consistency Ge doping. The absorption of MC-EDPFs achieved 15.876 dB/m at 1550nm and 10 dB/m at 980nm. The reflectivity of the fiber Bragg gratings (FBGs) written directly on the MC-EDPFs is as much as 96.84%.

Two-Axis Temperature-Insensitive Accelerometer Based on Multicore Fiber Bragg Gratings

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> We report a compact two-dimensional accelerometer based upon a simple fiber cantilever constructed from a short length of multicore optical fiber. Two-axis measurement is demonstrated up to 3 kHz. Differential measurement between fiber Bragg gratings written in the multicore fiber provides temperature-insensitive measurements. </para>

Coupling losses in perfluorinated multi-core polymer optical fibers

The aim of the present paper is to provide a comprehensive analysis of coupling losses in perfluorinated (PF) multi-core polymer optical fibers (MC-POFs), which consist of groups of 127 graded-index cores. In our analysis we take into account geometrical, longitudinal, transverse, and angular misalignments. We perform several experimental measurements and computer simulations in order to calculate the coupling losses for a PF MC-POF prototype. Based on these results, we propose several hints of practical interest to the manufacturer which would allow an appropriate connector design in order to handle conveniently the coupling losses incurred when connectorizing two PF MC-POFs.

Image amplifier based on Yb^3+-doped multi-core phosphate optical fiber

We demonstrate image amplification with a 19-pixel optical image amplifier array based on high gain per unit length Yb(3+)-doped phosphate glass optical fiber. The 19 pixels of the image amplifier provide spatially uniform image amplification whose gain can reach 30 dB/pixel or more with a fiber length of 10 cm. This image amplifier responds quickly to changes in the image position - with potential for GHz-level frame rates. This unique approach for image amplification offers low noise, high gain, and wide field of view in a compact fiber-based device.

Ultrafast-laser inscription of a three dimensional fan-out device for multicore fiber coupling applications

A fan-out device has been fabricated using ultrafast-laser waveguide-inscription that enables each core of a multicore optical fiber (MCF) to be addressed by a single mode fiber held in a fiber V-groove array (FVA). By utilizing the unique three-dimensional fabrication capability of this technique we demonstrate coupling between an FVA consisting of a one-dimensional array of fibers and an MCF consisting of a two-dimensional array of cores. When coupled to all cores of the MCF simultaneously, the average insertion loss per core was 5.0 dB in the 1.55 mum spectral region. Furthermore, the fan-out exhibited low cross-talk and low polarization dependent loss.

Fabrication of a range of SERS substrates on nanostructured multicore optical fibres

AbstractAn effective method for producing arrays of nanoscale triangles, rods and wells on the distal end of a silica optical fibre is presented. The structures are produced by applying a wet‐etch procedure to drawn‐down imaging fibres. Structural variation is achieved by altering the final diameter of the drawn fibre. Feature sizes of less than 100 nm can be readily achieved in this way. When coated with silver, surface‐enhanced Raman scattering enhancement factors of over 106 can be achieved, depending on the size and shape of the structures present. Copyright © 2006 John Wiley &amp; Sons, Ltd.

Two-axis bend measurement with Bragg gratings in multicore optical fiber.

We describe what is to our knowledge the first use of fiber Bragg gratings written into three separate cores of a multicore fiber for two-axis curvature measurement. The gratings act as independent, but isothermal, fiber strain gauges for which local curvature determines the difference in strain between cores, permitting temperature-independent bend measurement.

Two-dimensional bend sensing with a single, multi-core optical fibre

Measurement of two-dimensional bending in a structural element using intrinsic optical fibre strain gauges would normally require three sensors to be attached to, or embedded within, the structure. The same measurement can now be made using a single multi-core optical fibre, reducing deployment cost and increasing practicality. Fabrication of a novel three-core photonic crystal fibre is described. The ability of the fibre sensor to measure bend in two dimensions is demonstrated in the laboratory using interferometric interrogation at a single wavelength. Deployment of the sensor to measure the deformation of a bridge undergoing loading trials is described.

Bend measurement using Bragg gratings in multicore fibre

The first measurements of curvature made using Bragg gratings written in separate cores of a multicore optical fibre are described. The gratings act as independent, but isothermal, strain gauges. The difference in Bragg wavelength between the gratings provides a temperature-independent measurement of the local curvature.

Performances of endoscopic holography with a multicore optical fiber

A holographic setup that involves the use of a multicore optical fiber as an in situ recording medium has been developed. The hologram is transmitted to a CCD camera for electronic processing, and the image is reconstructed numerically, providing more flexibility to the holographic process. The performances of this imaging system have been evaluated in terms of the resolution limit and robustness relative to noise. The experimental cutoff frequency has been measured experimentally over a range of observation distances (4-10 mm) and presents a very good agreement with the predictions made by simulation. The system features a resolution of 5-µm objects for a 4-mm observation distance. The different sources of noise have been analyzed, and their influence on resolution has been proved to be nonrelevant.