Holder for optical fibre

Abstract

The invention relates to a holder (1) for an optical fibre, the holder (1) having at least one housing (3) for an optical fibre (60), the housing (3) having a proximal end (5) and a distal end (7), the housing (3) being optically penetrable at the ends, and the housing (3) comprising a flared portion (9) tapering towards the distal end (7).

Description

[0001] Description

[0002] Fiber optic support

[0003] DOMAIN

[0004] The invention relates to a support for an optical fiber, in particular a support for a plurality of fibers and in particular a plurality of fibers arranged in a ribbon or matrix form.

[0005] STATE OF THE ART

[0006] Fiber optic holders are used to hold one or a plurality of optical fibers in position. The plurality of optical fibers may in particular be arranged in the form of a ribbon and the fiber ribbon holder is in this case also referred to as a "Fiber Array Holder" abbreviated to FAH.

[0007] The supports may comprise a support body in which a triangular-shaped housing is formed. The housing is configured to accommodate the fiber. Once the fiber is placed in the housing, a cover of the support is then attached against the body and the fiber so as to fix the position of the fiber in the support body.

[0008] Such mounts require the handling of two separate parts to secure the fiber in the mount. There is a need to simplify fiber optic mounts.

[0009] EXPOSED

[0010] An aim of the present disclosure is to provide a simpler fiber optic support than in the prior art.

[0011] The object is achieved by means of a support for an optical fiber, the support having at least one housing for an optical fiber, the housing having a proximal end and a distal end, the housing being optically through at the ends, the housing comprising a flared portion tapering towards the distal end.

[0012] Such a support is advantageously and optionally completed by the following different characteristics taken alone or in combination: the flared portion has, with respect to a longitudinal direction passing through the ends, an angle of inclination less than or equal to 5 degrees, and preferably equal to 1.2 degrees, a transverse dimension of the housing measured in a plane orthogonal to the longitudinal direction increasing from the distal end towards the proximal end by a variation less than or equal to 40 μm and preferably equal to 10 μm; the flared portion defines, in a plane orthogonal to a longitudinal direction passing through the ends, a circle, a triangle or a hexagon; a membrane delimiting the housing at the distal end; the membrane comprises an anti-reflection layer or an optical filter facing the exterior of the support;the flared portion of the associated housing defines at the distal end a contour and a larger circle inscribed in the contour, the membrane having an orifice to leave free of material an axis centered on the larger inscribed circle; a cavity located on an edge of the support, the edge being defined by the membrane and a side of the support parallel to a longitudinal direction passing through the ends, the cavity opening outwards through an opening in the membrane and through an opening on the side of the support; the cavity is a first cavity, the support having a second cavity located on the edge of the support and opening outwards through an opening in the membrane and through an opening on the side of the support, the first cavity and the second cavity being arranged symmetrically with respect to a central plane passing through a center of the membrane;the housing is a first housing of a plurality of housings, the flared portion being a first flared portion of a plurality of flared portions, each flared portion being associated with a housing, the housings forming a row of housings, the support defining a channel which places two adjacent housings in fluid communication; a receiving surface, each housing opening at the proximal end into the receiving surface towards the outside, and a stopper extending from the receiving surface in the extension of the housings in a longitudinal direction passing through the ends, the stopper defining a plurality of grooves, each groove being associated with a housing; for each groove, a dimension of the groove measured at the proximal end is less than a dimension of the associated housing measured at the proximal end;for each groove, the flared portion of the associated housing defines at the distal end a contour and a larger circle inscribed in the contour, the dimension of the groove being greater than a dimension of the larger circle by a difference greater than or equal to 5 μm; and for each housing, a conduit which passes through the support, the conduit passing through the stop in the longitudinal direction Z until it opens outwards, the conduit opening into the housing at the distal end.;

[0013] The presentation also relates to an assembly comprising a support as just presented and an optical fiber inserted into the housing.

[0014] The disclosure further relates to a method of attaching an optical fiber to an optical fiber holder, the method comprising: - inserting a fiber into a housing of the holder along an axial direction of the fiber from a proximal end of the housing to a distal end of the housing, and

[0015] - centering of the fiber relative to the housing as it is inserted by means of a flared portion of the housing, the flared portion tapering towards the distal end.

[0016] DESCRIPTION OF FIGURES

[0017] Other characteristics and advantages will emerge from the following description, which is purely illustrative and non-limiting, and must be read in conjunction with the appended drawings in which: Figure 1 is a schematic representation of a fiber support; Figures 2 to 5 are schematic representations of a section of a fiber support; Figure 6 is a schematic representation of a fiber support; and Figure 7 is a schematic representation of a method of fixing a fiber.

[0018] DETAILED DESCRIPTION OF THE INVENTION

[0019] Fiber optic support housing

[0020] In relation to figures 1 and 2, a support 1 for an optical fiber has at least one housing 3 for an optical fiber. The support 1 comprises an internal wall 2 closed on itself which defines in its interior the housing 3. The support 1 extends in a so-called longitudinal direction Z. The housing extends over a height 4 in the longitudinal direction Z from a proximal end 5 to a distal end 7. The height 4 is approximately 500 pm. The height is greater than or equal to 100 pm and less than or equal to 1 mm, preferably greater than or equal to 400 pm and less than or equal to 600 pm. X and Y denote two directions orthogonal to the Z direction. The X and Y directions are orthogonal to each other. The X direction corresponds to a distribution direction and the Y direction to a stop direction.

[0021] In a transverse plane, that is to say a plane orthogonal to the longitudinal direction Z, or a plane parallel to the directions X and Y, the housing defines a section closed on itself. The edges of the section are included in the internal wall 2.

[0022] The housing 3 is optically through at the ends, which means that light can be transmitted through the housing from the proximal end 5 to the distal end 7 or vice versa from the distal end 7 to the proximal end 5. In other words, light can propagate along an axis parallel to the longitudinal direction Z, the axis passing through the housing 3, the proximal end 5 and the distal end 7.

[0023] The support 1 may in particular have a receiving surface 26 which is parallel to the X and Y directions. B denotes the plane parallel to the X and Y directions and passing through the receiving surface. Plane B separates the support into a lower part in which the housings are located and an upper part. The housing 3 opens outwards through the receiving surface 26, thus defining the proximal end 5.

[0024] It should be noted that the upper and lower parts may have different chemical compositions. The two parts can be joined by polymer bonding or by anodic Si / Si welding.

[0025] The support 1 may further comprise a membrane 46 which defines one end of the support 1 in the longitudinal direction Z. The membrane 46 extends parallel to the X and Y directions. The membrane 46 is parallel to the receiving surface 26. When present, the membrane 46 delimits the housing 3 at the distal end 7. The edges of the housing are then defined on the one hand by the internal wall 2 in the X and Y directions and on the other hand by the membrane 46 in the Z direction. If one end of a fiber is inserted into the housing in the longitudinal direction, from the proximal end 5 towards the distal end 7, the membrane can serve as a stop for the fiber.

[0026] The membrane 46 can in particular be made of a laminated resin which has then been glued to the rest of the support 1 comprising the housings 3.

[0027] The membrane is the part of the support that is intended to be glued against the object that is intended to receive the light from the fibers inserted into the support.

[0028] The membrane 46 has a thickness in the longitudinal direction Z less than or equal to 30 pm. It may be greater than or equal to 2 pm, or even 5 pm. It is for example 20 pm.

[0029] The membrane 46 has an optical index which is greater than or equal to 1.4 and less than or equal to 1.6. For example, the optical index is 1.5. This optical index is close to or even equal to the optical index of the optical fiber intended to be inserted into the support.

[0030] The membrane 46 may be textured or fragmented, that is to say that the membrane is not a continuous and regular layer but it has reliefs with a certain periodicity. It may take the form for example of a grid or a paving. This textured or fragmented configuration of the membrane 46 makes it possible to better manage thermal expansions at the support / object interface. The membrane is in fact located at this interface. If the object and the support have different thermal expansion coefficients, there may be a risk of degradation of the support / object connection. This risk can be reduced thanks to the textured or fragmented configuration of the membrane 46. Advantageously, the membrane 46 may have an anti-reflective layer 58 facing the outside of the support. The anti-reflective layer may for example be deposited on the membrane.The layer makes it possible, for example, to improve the light transmission through the housing, when the light propagates in the longitudinal direction Z from the proximal end 5 to the distal end 7. This is particularly the case if this light is carried by a fiber inserted into the housing.

[0031] As an alternative to the anti-reflective coating, the membrane can include an optical filter. This filter allows light to pass only in a certain wavelength range.

[0032] The housing 3 comprises a flared portion 9 tapering towards the distal end 7. The flared portion 9 is included in the internal wall 2. The flared portion 9 extends from the proximal end 5 to the distal end 7 in the longitudinal direction Z. The portion 9 defines in section by a transverse plane a contour. The contour may or may not be closed. At each height in the longitudinal direction Z, the portion 9 can be virtually cut by a transverse plane and the intersection between the transverse plane and the portion 9 defines the contour. In particular, the contour can be characterized by a transverse dimension, that is to say a length in the transverse plane between two points of the contour facing each other.The fact that the portion 9 tapers towards the distal end 7 means that the transverse dimension of the contour decreases when traveling in the longitudinal direction from the proximal end 5 towards the distal end 7.

[0033] The narrowing of the flared portion allows the technical effect of guiding the optical fiber as it is inserted into the housing. If one end of a fiber is inserted into the housing in the longitudinal direction, from the proximal end 5 to the distal end 7, the transverse position of the fiber end is increasingly constrained so that the end is guided to an ideal position when it reaches the distal end 7. The fiber can then be glued into the housing. Thanks to the flared portion, the holder can be monobloc, that is to say, the holder is in one piece, while still allowing the fiber to be fixed. The holder is no longer formed of two separate pieces that need to be manipulated and fixed together to fix the fiber in the holder.

[0034] In addition, the flared portion surrounding the end of the fiber allows the glue intended to fix the fiber in the holder to be distributed all around the fiber. This allows a self-centering effect of the fiber in the housing and better positioning precision.

[0035] It should be noted that if the support is monobloc, it can however include different zones of different chemical composition. In particular it can include several layers of different chemical composition stacked in the longitudinal direction Z.

[0036] It can be provided that at each height in the longitudinal direction Z, the flared portion 9 defines a contour and a larger circle inscribed in the contour, the larger inscribed circle being tangent at at least three points of the contour. The three tangent points are distributed over more than half of the circle, that is to say they define an angular sector of the circle which measures more than 180°. The tangent character at three points implies that the larger inscribed circle is inside the contour. As the wall narrows, this implies that the diameter of the larger circle decreases when traveling in the longitudinal direction from the proximal end 5 towards the distal end 7.

[0037] A position in the transverse plane XY of a center of the largest inscribed circle in the contour does not vary with height in the longitudinal direction Z. This means that the centers of the largest inscribed circles are aligned along an axis parallel to the longitudinal direction Z. This axis is called the housing axis. The housing is centered on this axis parallel to the longitudinal direction Z. It is on this axis that we wish to align the fiber core that is intended to be inserted into the housing.

[0038] At the distal end 7, the flared portion defines in a transverse plane a section and a larger inscribed circle which is adjusted relative to the diameter of the fiber that one wishes to insert. This larger circle at the distal end 7 is designated by target circle. The target circle has a diameter greater than the diameter of the fiber. The mechanical clearance between these two diameters advantageously corresponds to less than 0.5 μm so as to guarantee satisfactory precision in the placement of the fiber.

[0039] The narrowing of the flared portion is such that in the housing, the flared portion approaches the axis of the housing when moving along the insertion direction toward the distal end.

[0040] It may also be provided that the flared portion 9 defines, in a plane orthogonal to the longitudinal direction Z, a circle, a triangle or a hexagon. This means that the contour defined by the flared portion 9 in section by a transverse plane defines a constant shape over the entire height of the housing in the longitudinal direction Z, this shape being able to be a circle, a triangle or a hexagon. It may in particular be a regular hexagon, an equilateral or isosceles triangle.

[0041] It is specified here that a form defines:

[0042] - a circle when this shape is a whole circle or part of a circle, the part of the circle being sufficiently large to allow the geometric parameters of the circle to be identified, namely its center and its diameter,

[0043] - a triangle when this shape is a whole triangle or part of a triangle, the part of the triangle being large enough to allow the geometric parameters of the triangle to be identified, namely the position of the three vertices of the triangle, and - a hexagon when this shape is a whole hexagon or part of a hexagon, the part of the hexagon being large enough to allow the geometric parameters of the hexagon to be identified, namely the position of the six vertices of the hexagon.

[0044] The circular and hexagonal shapes allow the size of the support 1 to be reduced while maintaining good performance.

[0045] In relation to Figure 3 which illustrates a section through a transverse plane, the flared portion 9A located on the left of the figure defines a contour which has a triangular shape defined by the points P1, P2 and P3. The section is defined by the successive segments [P3P1], [P1 P2] and [P2C1] so that the shape of the section is part of a triangle. The shape clearly defines a triangle because the vertices P1 and P2 are clearly visible and by virtually extending the segment [P2C1], we obtain the point P3 which is the third and last vertex of the triangle.

[0046] Figure 3 also shows circle 22, which is the largest circle inscribed in the contour defined by the flared portion 9A. Circle 22 is tangent to the contour at points T1, T2 and T3. In this situation, the largest circle 22 inscribed in the contour is tangent to the contour at three points.

[0047] Advantageously, the membrane 46 may have an orifice 62 to leave a longitudinal axis free of material, that is to say an axis parallel to the longitudinal direction Z, centered on the housing. This is for example the axis of the housing. In this way, the membrane can constitute a stop for the insertion of the fiber, while allowing light transmitted by the fiber to pass through. For example, the orifice 62 can be adapted so that it is sufficiently narrow to block the fiber and sufficiently wide to leave the fiber core free of material. The orifice can in particular leave an axis free of material centered on the largest circle inscribed in the contour defined by the flared portion 9 in section by a transverse plane.

[0048] It may also be provided that the flared portion 9 has an angle 10 of inclination relative to the longitudinal direction Z. This may in particular correspond to the situation where the shape of the contour does not vary as a function of the height, the dimension of the contour decreasing linearly as a function of the height in the longitudinal direction Z from the proximal end 5 towards the distal end 7.

[0049] In a section plane parallel to the longitudinal direction Z, as illustrated in figure 2, the flared portion 9 appears as a straight segment directed in an oblique direction relative to the longitudinal direction Z. An angle 10 can be defined between the flared wall 9 and the longitudinal direction.

[0050] The angle of inclination 10 is advantageously less than or equal to 5 degrees, and even more preferably equal to 1.2 degrees.

[0051] When the angle of inclination takes a value less than or equal to 5 degrees, the transverse dimension of the housing increases from the distal end 7 towards the proximal end 5 by a variation less than or equal to 40 pm and preferably equal to 10 pm.

[0052] Multiple housing units

[0053] The support 1 may comprise more than one housing 3. Each housing is intended to accommodate a fiber from a plurality of fibers, for example from a fiber ribbon or a fiber matrix.

[0054] Each housing of the plurality of housings conforms to the housing that was presented previously. Each housing can therefore be associated with a flared portion. Ideally, the housings of the plurality of housings are identical to each other. The housings are distributed according to the distribution direction X so as to define a row of housings. Figure 1 illustrates this situation. The distance separating two adjacent housings is preferably constant. It corresponds to the gap (or "pitch" in English) between two adjacent fibers in the ribbon that one seeks to insert into the support. This arrangement allows in particular the support 1 to accommodate a ribbon of optical fibers. This gap is greater than or equal to 40 pm and less than or equal to 1000 pm. The gap may in particular be 50 pm, 82 pm, 127 pm, 250 pm or 500 pm. Such supports possibly have a gap between two adjacent fibers that is smaller than in the prior art.

[0055] Alternatively, the housings may be distributed along the distribution direction X and the stop direction Y so as to define a matrix of housings. The distance separating two adjacent housings is preferably constant. It corresponds to the gap (or "pitch" in English) between two adjacent fibers in the matrix that one seeks to insert into the support. This arrangement notably allows the support 1 to accommodate a matrix of optical fibers.

[0056] When the dwellings define a row of dwellings, these are advantageously aligned according to the distribution direction X. With reference to Figure 1, we can define a plane A parallel to the distribution direction X and passing through the center of each dwelling. Plane A can in particular pass through the axes of the dwellings when they can be defined.

[0057] When the housings define a row of housings, the support 1 defines a channel 16 which places two adjacent housings in fluid communication. The channel extends parallel to the distribution direction X and has a central plane parallel to the longitudinal direction Z and to the distribution direction X. With reference to Figure 3, three housings 3A, 3B and 3C define a row of housings along the distribution direction X. The housings 3A, 3B and 3C are identical and correspond to flared portions 9A, 9B and 9C which define in section by a transverse plane a contour which has a triangular shape, and more precisely an isosceles or equilateral triangle shape.

[0058] The channel has a smaller width 20 measured in the Y stop direction.

[0059] The central housing 3B corresponds in figure 3 to the triangle Q1, Q2 and Q3 and the housing on the right 3C corresponds to the triangle R1, R2 and R3.

[0060] The support 1 comprises the flat walls 18A and 18B which define the channel 16. The flat walls 18A and 18B are part of the internal wall 2. The internal wall 2 defines the set of housings 3A, 3B and 3C. The internal wall 2 comprises on the one hand the flared portions 9A, 9B and 9C which, as already described, can be inclined relative to the longitudinal direction Z and on the other hand the flat walls 18A and 18B which extend along a plane. The flat walls 18A are parallel to the distribution direction X, they are located on either side of the central plane of the channel. The flat walls can be parallel to the longitudinal direction Z. In this case for each wall the distance from the wall to the central plane is constant. Alternatively the flat walls can be inclined relative to the longitudinal direction Z.When they are inclined relative to the longitudinal direction Z, each wall moves away from the central plane as one moves away from the distal end. The flat walls then have an angle relative to the longitudinal direction Z. This angle is advantageously less than or equal to 5 degrees, and even more preferably equal to 1.2 degrees. It can be chosen equal to the angle 10 of inclination of the flared portion 9 relative to the longitudinal direction Z. The straight walls 18A and 18B make it possible to put the housings 3A, 3B and 3C in fluid communication.

[0061] The wall 18A opens the triangular shape P1 P2P3 of the housing 3A at point C1 by removing the segment [C1 P3] shown in dotted lines in figure 3. The wall 18A opens the triangular shape Q1Q2Q3 of the housing 3B at point C2 by removing the segment [C2Q1] shown in dotted lines in figure 3.

[0062] The wall 18B opens the triangular shape Q1Q2Q3 of the housing 3B at point C3 by removing the segment [C3Q3] shown in dotted lines in figure 3.

[0063] The wall 18B opens the triangular shape R1 R2R3 of the housing 3C at the point C4 by removing the segment [C4R1] shown in dotted lines in figure 3.

[0064] At the height along the longitudinal direction Z corresponding to the section in cross-section by a transverse plane, the walls 18A and 18B are separated by a distance 20 from the segment [P1 R3]. This distance 20 corresponds to the smallest width 20. The fluid communication of the housings makes it possible in particular to circulate the glue from one housing to another.

[0065] The presence of the channel allows the glue and any air bubbles in contact with the glue to flow out when inserting the fibers into the housing and when annealing the glue. The gluing step is simpler to carry out and better air evacuation is obtained from the housing. Ultimately, the attachment of the fiber to the support is better.

[0066] The distance 20 is chosen to be large enough to allow the glue to pass through. The distance 20 can be chosen to be small enough to meet the condition that the flared portion 9 defines at each height in the longitudinal direction Z a contour and a larger inscribed circle in the contour, the larger inscribed circle being tangent at at least three points of the contour, the three points being distributed over more than half of the circle. With reference to Figure 3, the distance 20 is chosen to be small enough so that the point C1 is located between the tangent point T3 and the point P3, so that the flared portion 9A always includes the tangent point T3.

[0067] In relation to Figure 5, the support 1 comprises three housings 3A, 3B and 3C which define a row of housings in the distribution direction X. The housings 3A, 3B and 3C are identical and correspond to flared portions 9A, 9B and 9C which define in section by a transverse plane a contour which has the shape of a regular hexagon. The largest inscribed circle 22 has been represented in the contour given by the section of the flared portion 9A by a transverse plane. The circle 22 is tangent to the contour at the points U1, U2, U3, U4, U5 and U6. The circle 22 has a diameter 24.

[0068] The support 1 comprises the straight walls 18A, 18B, 18C and 18D which define the channel 16. The straight walls 18A, 18B, 18C and 18D are part of the internal wall 2. These straight walls 18A, 18B, 18C and 18D allow the housings 3A, 3B and 3C to be placed in fluid communication. Each wall opens two hexagonal shapes by removing a segment of the contour defined by one of the flared portions 9A, 9B and 9C. The removed segments are shown in dotted lines in Figure 5. The vertices H1, H2, H3 and H4 of the regular hexagons are removed by the walls 18A, 18B, 18C and 18D. The channel 16 has a width 20.This width 20 can be chosen to be small enough to respect the condition according to which the flared portion 9 defines at each height in the longitudinal direction Z a contour and a larger circle inscribed in the contour, the larger circle inscribed being tangent at at least three points of the contour, the at least three points being distributed over more than half of the circle. For example in figure 5, the distance 20 is chosen small enough not to eliminate both the tangent point U4 and the tangent point U5.

[0069] Stopper

[0070] When the support 1 comprises several housings, and with reference to figures 1 and 2, the support 1 may comprise a stopper 28 which extends from the receiving surface 26 in the extension of the housings 3 in the longitudinal direction Z. The stopper 28 is located in the upper part of the support 1 defined on one side of the plane B passing through the receiving surface 26. The stopper 28 extends from the receiving surface 26 to an upper end 27 of the support 1.

[0071] For each housing 3, the proximal end 5 is located between the stopper 28 and the distal end 7.

[0072] The stopper defines a plurality of grooves 30, each groove 30 being associated with a housing 3. Each groove is located in the extension of the associated housing 3. The stopper comprises a plurality of faces, each face defining a groove. For each housing, the face defining the associated groove is at least partially in the extension of the flared portion 9. Each face and each groove extend along the longitudinal direction Z of the receiving surface 26 to one end of the stopper. In other words, each face and each groove extend over the entire height of the stopper in the longitudinal direction Z.

[0073] The stopper 28 faces the receiving surface 26 in the stop direction Y. For each housing, the proximal end 5 is located between the stopper 28 and the receiving surface 26. Each groove is open in a first direction of the stop direction Y. The face corresponding to a groove extends around the axis of the corresponding housing over an angular sector less than or equal to 180° on one side of the plane A parallel to the distribution direction X and passing through the center of each housing. The plane A may in particular pass through the axes of the housings. This side corresponds to a second direction of the stop direction Y, opposite to the first direction. In other words, the faces of the stopper 28 defining the grooves 30 are located on only one side of the plane A so that the grooves of the stopper are open towards the other side of this plane.

[0074] Each groove 30 defines an open contour in cross-section by a transverse plane. The open contour has a shape similar to the shape of the closed contour defined by a cross-section of the flared wall 9 by a transverse plane. A similar shape corresponds for example to a triangle of the same nature (equilateral, isosceles, etc.) oriented in the same way in the transverse plane, a circle or a hexagon of the same nature (for example regular) oriented in the same way in the transverse plane. The open contour and the closed contour have similar but not identical shapes, in particular because they can have different dimensions.

[0075] Figure 4 is a view of the support in projection in a transverse plane XY. In relation to this figure 4, the stopper 28 has a first width 36 measured in the stop direction Y between a rear end 29 of the support 1 in this direction Y and the groove 30. More precisely, the first width 36 is measured between the rear end 29 and the part of the groove 30 closest to this rear end 29. The first width 36 is approximately 50 μm, it is greater than or equal to 30 μm and less than or equal to 100 μm. This first width 36 is sufficient to ensure minimum strength of the support 1 and the stopper 28.

[0076] In the example of Figure 4, the grooves 30 have an open contour which follows the shape of a regular hexagon. The grooves 30 correspond to the solid lines. The dotted lines which complete the hexagons correspond to a section of the flared walls of the housings 3A 38 and 3C which are in the extension of the grooves 30.

[0077] The stopper 28 has a second width 38 measured along the stop direction Y which corresponds to the width of the grooves in this direction Y. The second width 38 is measured between the part of the groove 30 closest to the rear end 29 and the part of the groove 30 furthest from this rear end 29. The part of the groove 30 furthest from this rear end 29 is located on the plane A. The value of the second width 38 can be chosen according to the diameter of the fibers to be inserted. As for the housings 3, the open contour of the grooves 30 can be characterized by a transverse dimension, that is to say a length in the transverse plane between two points of the contour facing each other.

[0078] Advantageously, a dimension 32 of the groove 30 measured at the proximal end 5 is less than a dimension 12 of the associated housing 3 measured at the proximal end 5.

[0079] The dimension 32 is a transverse dimension of the groove 30 measured in the plane B passing through the receiving surface 26.

[0080] Dimension 12 is a transverse dimension of housing 3 measured in plane B.

[0081] It can further be provided that the flared portion of the housing 3 defines at the distal end 7 a contour and a larger circle inscribed in the contour, the dimension 32 of the groove 30 measured at the proximal end 5 being greater than a dimension of the larger circle by a difference greater than or equal to 2 pm or even greater than or equal to 5 pm.

[0082] The largest circle inscribed at the distal end 7 is the target circle. The dimension of the target circle may in particular be its diameter. The dimension 32 of the groove 30 may be measured as the length of the segment joining two points on the face defining the groove, the segment passing through the axis of the housing. The dimension 32 is greater than the diameter of the target circle. The difference “dimension 32” minus “diameter of the target circle” is greater than or equal to 2 μm or even greater than or equal to 5 μm.

[0083] The groove may be configured to have a transverse dimension along the longitudinal direction Z that is constant as illustrated in Figure 2. Alternatively, this dimension may decrease toward the proximal end 5 or increase toward the proximal end 5. In all cases the transverse dimension is greater than the diameter of the target circle at all heights along the longitudinal direction Z.

[0084] The receiving surface 26 extends in the plane B from the proximal ends 5 (or the proximal end 5 if there is only one housing) in the stop direction Y to a front end 31 of the support 1. This surface makes it possible to guide the ends of a plurality of fibers 60 (in the form of a ribbon for example). The fibers are placed slightly above the receiving surface. The fibers 60 are then moved in the stop direction Y towards the housings. The travel of the fibers 60 is stopped by the stopper 28, when the fibers 60 come into contact with the grooves 30 of the stopper 28. Each fiber 60 is placed in a groove 30 so that each fiber 60 is opposite the housing 3 associated with the groove 30. The fibers can then be moved in the direction Z to enter the housing so as to place the end of each fiber at the distal end 7 of the housing.

[0085] The support 1 may comprise ramps 34 which are located opposite one another in the distribution direction X and on either side of the receiving surface 26. The ramps 34 extend from the receiving surface 26 in the longitudinal direction Z to the upper end 27 of the support 1. The height of the ramps 34 in the longitudinal direction Z is equal to the height of the stopper 28 in the longitudinal direction Z. The ramps 34 extend in the stop direction Y from the stopper to the front end 31 of the support 1.

[0086] The ramps have a third width 40 and a fourth width 42 in the abutment direction Y. The fourth width 42 extends from the front end 31 of the support 1 towards the rear end 29. Over this fourth width 42, a dimension of the ramps 34 in the distribution direction X is constant. This corresponds to a distance 44 between the ramps 34 in the distribution direction X, or equivalently to a dimension of the receiving surface 26 in the distribution direction X, which is constant over the fourth width 42. Alternatively, the dimension of the ramps 34 in the distribution direction X may increase as one approaches the rear end 29. This corresponds to a distance 44 between the ramps 34 in the distribution direction X which decreases as one approaches the rear end 29.

[0087] The third width 40 extends from the plane A towards the front end 31. On this third width 40, the dimension of the ramps 34 in the distribution direction X increases as one approaches the rear end 29. This corresponds to a distance 44 between the ramps 34 in the distribution direction X which decreases as one approaches the rear end 29. In other words, the dimension of the receiving surface 26 in the distribution direction X as one approaches the rear end 29. The ramps 34 thus make it possible to guide the fibers when they are moved above the receiving surface 26 in the direction of the housings 3.

[0088] It should be noted that the distance 44 is a continuous quantity according to the stop direction Y on the third width 40 and the fourth width 42 and in particular at the transition between these two widths.

[0089] The volume defined above the receiving surface 26 and between the ramps 34 is a reserve volume which communicates with the housings 3. Thus, when gluing the fibers in the housing, if too much glue has been used, it can fill the reserve volume. The advantage is not to have to respect a small volume of glue so that the glue does not overflow from the housings 3.

[0090] Glue drain pipe

[0091] In relation to Figure 2, the support 1 may comprise for each housing a conduit 64 which passes through the support 1. The conduit 64 opens outwards through the stopper. More precisely, the conduit passes through the stopper 28 in the longitudinal direction Z until it opens outwards. The conduit opens outwards through the upper end 27 of the support 1. In a first section of the conduit which opens outwards through the upper end 27, the conduit extends parallel to the longitudinal direction Z so as to allow the glue to flow through the first section in the longitudinal direction Z. The first section of the conduit has a dimension of its cross-section to the longitudinal direction Z. This dimension may be constant or variable. If it is variable, then it increases as one approaches the upper end 27. The dimension is greater than or equal to 30 μm.

[0092] In addition, the conduit opens into the housing at the distal end. In a second section of the conduit which opens into the housing, the conduit extends parallel to the membrane so as to allow flow of the adhesive through the second section towards the first section, the flow taking place generally in a direction parallel to the membrane. The second section of the conduit has a rectangular section. A first dimension of the second section in the longitudinal direction Z is constant. It is greater than or equal to 5 μm and less than or equal to 500 μm. A second dimension of the second section in a direction parallel to the membrane 46 is constant or variable. If it is variable, then the second dimension increases as one moves away from the housing 3. It is greater than or equal to 5 μm and less than or equal to 50 μm.

[0093] The conduit opens into the housing at the distal end, i.e. an internal wall of the second section is the membrane 46.

[0094] The conduit 64 places the bottom of the housing 3 on the side of the distal end 7 in fluid communication with the top of the stopper 28 on the side of the upper end 27. The first section and the second section of the conduit are in fluid communication in a bent zone of the conduit.

[0095] This conduit can serve as an evacuation route for glue placed in the housing before the insertion of the fibers or for air bubbles pushed by this same glue. The introduction of the fibers generates pressure exerted on the glue, and in particular on the glue present in the bottom of the housing. The presence of the conduit 64 makes it possible to evacuate the glue, to limit the resistance to the introduction of the fiber and not to hinder the correct positioning of the fiber.

[0096] The first section can advantageously be aligned with the housing 3 in the stop direction Y, the housing 3 being located between the receiving surface 26 and the first section.

[0097] It should be noted that two second sections can be in fluid communication with a single first section. In this way, the first section is common to the two second sections, the first section allowing the flow of the glue from each of the two second sections.

[0098] It should be noted that all of the second sections can be in fluid communication with a single first section. The first section can then take the form of a slot which extends in the distribution direction X, the housing 3 being located between the receiving surface 26 and the slot.

[0099] Lateral cavities

[0100] Optionally, the support 1 may have a cavity 48 located on an edge of the support. The edge is defined by the membrane 46 and a side of the support parallel to the longitudinal direction Z. With reference to FIG. 6, a cavity 48 may for example be located on the edge defined by the membrane 46 and the side corresponding to the front end 31 of the support 1. The front end 31 corresponds to one end of the support 1 in the abutment direction Y, the receiving surface 26 extending from this front end 31. The cavity 48 opens outwards through an opening 54 in the membrane and through an opening 56 on the side of the support.

[0101] The support 1 comprises wall sections which define the cavity 48. These sections join the outer walls of two faces of the support 1 so that the cavity opens outwards through the two faces.

[0102] The cavity 48 is advantageously located in the longitudinal direction Z outside the receiving surface 26. In other words, in projection onto a transverse plane orthogonal to the longitudinal direction Z, the cavity 48 does not overlap with the receiving surface 26. The cavity 48 may, for example, be located under the ramps 34, that is to say that in projection onto a transverse plane, the cavity overlaps with one of the ramps 34, or even the projection of the cavity 48 is entirely contained in the projection of one of the ramps 34. The cavities are therefore distant from a central zone of the support 1 so that they can be described as lateral cavities.

[0103] The support may also comprise two cavities. The two cavities are on the same edge of the support defined by the membrane and one side of the support. The cavities both open outwards through an opening in the membrane and through an opening in the side of the support. The first cavity and the second cavity are arranged symmetrically with respect to a central plane passing through a center of the membrane. In particular, a plane C parallel to the longitudinal direction Z and the abutment direction Y may be defined, the plane C passing through a center of the membrane. With reference to FIG. 6, the two cavities 48 are symmetrical to each other with respect to the plane C.

[0104] The cavities are used to inject glue when the support 1 is to be fixed against an object that is intended to receive the light from the fibers. More precisely, it is the membrane 46 of the support 1 that is glued to the object. Once the support 1 is applied against the object, the cavity is accessible via the side of the support parallel to the longitudinal direction Z. Glue can therefore be injected into the cavity through the opening in this side. The glue flows to the membrane and the membrane / object interface via the opening in the membrane.

[0105] This bonding can be carried out once the fibers have been introduced and fixed in the support 1. Active bonding can be carried out in particular, during which the relative position between the support and the object is finely adjusted, then glue is injected into the cavities to consolidate the previously optimized position.

[0106] When two cavities are used, the symmetrical arrangement of the cavities gives a symmetrical distribution of the glue between the support 1 and the object, and ultimately a more efficient and stronger bond. Symmetry makes it possible to compensate for the effects of variations in the dimensions of the glue on the final centering of the object.

[0107] Method of fixing an optical fiber

[0108] A support 1 as just presented makes it possible to implement a process P to fix a fiber.

[0109] We will present a mode of implementation of this process P, with reference to figure 7.

[0110] During a first step E1, a fiber 60 is inserted into a housing 3 of the support 1 along an axial direction of the fiber from the proximal end 5 of the housing 3 to the distal end 7 of the housing 3. The axial direction of the fiber corresponds to the longitudinal direction Z of the housing 3. During a second step E2, the fiber 60 is centered relative to the housing 3 as it is inserted by means of the flared portion 9 of the housing 3, the flared portion 9 tapering towards the distal end 7.

[0111] It should be noted that when the support 1 comprises a plurality of housings, a plurality of fibers can be inserted into the support 1 during step E1 and a plurality of fibers can be centered during step E2.

[0112] In a third step E3, the fiber or fibers are fixed by gluing in the support. This step E3 includes the introduction of glue into the support and a step of solidifying the glue, for example by raising the temperature. The introduction of glue can be carried out once the fibers have been inserted and centered.

[0113] According to an alternative, it is possible to introduce glue into the housing before introducing the fiber. In this alternative, the method P comprises the optional step E3A which is carried out before step E1. In this alternative, the glue makes it possible to evacuate the air outside the housing so as to prevent the presence of an air bubble between the fiber and the membrane. In this alternative, the glue used advantageously has the same optical index as the membrane and the optical core of the fiber. This makes it possible to ensure the continuity of optical index on the optical path from the fiber to the exit of the membrane. In this alternative, the support 1 advantageously comprises evacuation conduits 64 so that the fibers are not blocked in their insertion by the presence of glue previously introduced into the housing 3.

[0114] It should be noted, in relation to step E3, that the volume defined above the receiving surface 26 and between the ramps 34 can accommodate glue which would come out of the housings 3 once the fibers are surrounded by glue. It should also be noted that the first step E1 can comprise a sub-step E1A during which the ends of the fibers (or the end of the fiber) are placed opposite the receiving surface 26 without bringing them into contact with this surface, then a sub-step E1B during which the ends of the fibers are moved towards the housings 3 until the fibers 60 come into contact with the grooves 30 of the stopper 28.

[0115] In the case where the fibers to be inserted are distributed in the form of a matrix, only the first line of fibers is placed in abutment against the grooves 30 of the stopper 28. This abutment places each fiber of the matrix opposite one of the housings of the support.

[0116] A step E4 of bonding the support 1 to the object intended to receive the light transmitted by the fiber or fibers may be provided. Step E4 may in particular comprise bringing the membrane into contact with the object, injecting glue into a cavity 48 through the side of the support which is parallel to the longitudinal direction Z, and bringing the glue into contact with the membrane and the object through the opening in the membrane.

[0117] A support 1 as just presented comprises a stack of layers in the longitudinal direction Z. In particular, the support 1 comprises the lower layer comprising the housings 3. The support 1 may comprise the upper part comprising the stopper 28 and the grooves 30. The support 1 may comprise the membrane 46 and its possible anti-reflection layer. The structure of the support 1 according to a stack makes it possible to produce the support 1 layer by layer from a single material or a plurality of materials. In other words, the chemical composition may vary from one layer to another. This makes it possible to envisage the production of a set of supports on a polymer, glass or silicon wafer, which makes it possible to pool a certain number of steps in the production of the supports. This is particularly the case for the production of the membrane, possibly textured, for the anti-reflection layer or the filter.Silicon machining methods such as deep reactive ion etching, lithography, glass casting or etching techniques (e.g., femtosecond laser), as well as additive manufacturing methods such as lamination, polymer, anodic or eutectic welding, and molecular bonding can be used.

[0118] It should be noted that the production of the support layer by layer makes it easier to produce the flared portions 9, the flat walls 18 and the evacuation conduits 64.

[0119] It should be noted that the production of the support layer by layer makes it possible to produce supports for which the distance between two adjacent fibers can be chosen. The manufacturing method allows flexibility in the manufacture of the support and to produce supports for which the distance between two adjacent fibers is smaller than in the prior art. This distance is greater than or equal to 40 pm and less than or equal to 1000 pm. The distance may in particular be 50 pm, 82 pm, 127 pm or 250 pm or 500 pm.

Claims

CLAIMS 1. Support (1) for optical fiber, the support (1) having at least one housing (3) for an optical fiber (60), the housing (3) having a proximal end (5) and a distal end (7), the housing (3) being optically through at the ends, the housing (3) comprising a flared portion (9) tapering towards the distal end (7), the housing (3) being a first housing of a plurality of housings, the flared portion (9) being a first flared portion of a plurality of flared portions, each flared portion being associated with a housing, the housings forming a row of housings, the support defining a channel (16) which places two adjacent housings in fluid communication, the support (1) comprising: - a receiving surface (26) extending in a stop direction (Y), each housing opening at the proximal end (5) into the receiving surface (26) towards the outside, and - a stopper (28) extending from the receiving surface (26) in the extension of the housings in a longitudinal direction (Z) passing through the ends, the longitudinal direction (Z) being orthogonal to the stop direction (Y), the stopper (28) defining a plurality of grooves (30), each groove (30) being associated with a housing.

2. Support according to claim 1 in which the flared portion (9) has, with respect to a longitudinal direction (Z) passing through the ends, an angle of inclination (10) less than or equal to 5 degrees, and preferably equal to 1.2 degrees, a transverse dimension of the housing measured in a plane orthogonal to the longitudinal direction (Z) increasing from the distal end (7) towards the proximal end (5). with a variation less than or equal to 40 pm and preferably equal to 10 pm.

3. Support according to any one of claims 1 and 2, in which the flared portion (9) defines, in a plane orthogonal to a longitudinal direction (Z) passing through the ends, a circle, a triangle or a hexagon.

4. Support according to any one of claims 1 to 3 comprising a membrane (46) delimiting the housing (3) at the distal end (7).

5. Support according to claim 4 in which the membrane (46) comprises an anti-reflective layer (58) or an optical filter facing the exterior of the support (1).

6. Support according to any one of claims 4 and 5, in which the flared portion (9) of the housing (3) defines at the distal end (7) a contour and a larger inscribed circle (22) in the contour, the membrane (46) having an orifice (62) to leave free of material an axis centered on the larger inscribed circle (22).

7. Support according to any one of claims 4 to 6 having a cavity (48) located on an edge (50) of the support, the edge (50) being defined by the membrane (46) and a side of the support (1) parallel to a longitudinal direction (Z) passing through the ends, the cavity (48) opening outwards through an opening (54) of the membrane (46) and through an opening (56) on the side of the support.

8. Support according to claim 7 in which the cavity (48) is a first cavity, the support having a second cavity located on the edge (50) of the support and opening outwards through an opening in the membrane and through an opening on the side of the support, the first cavity and the second cavity being arranged symmetrically with respect to a central plane (C) passing through a center of the membrane.

9. Support according to any one of claims 1 to 8 in which, for each groove (30), a dimension (32) of the groove (30) measured at the proximal end (5) is less than a dimension (12) of the associated housing (3) measured at the proximal end (5).

10. Support according to claim 9 in which, for each groove (30), the flared portion (9) of the associated housing (3) defines at the distal end (7) a contour and a larger inscribed circle (22) in the contour, the dimension (32) of the groove (30) being greater than a dimension (14) of the larger circle (22) by a difference greater than or equal to 5 μm.

11. Support according to any one of claims 1 to 10 comprising, for each housing, a conduit (64) which passes through the support, the conduit (64) passing through the stopper (28) in the longitudinal direction (Z) until it opens outwards, the conduit (64) opening into the housing at the distal end (7).

12. Assembly comprising a support (1) according to any one of claims 1 to 11 and an optical fiber (60) inserted into the housing 13. A method of attaching a plurality of optical fibers (60) to a support (1), the method comprising: - an arrangement of the ends of the fibers opposite a receiving surface (26) of the support (1), - a movement in a stop direction (Y) of the ends of the fibers towards housings (3) of the support (1) so that the fibers (60) come into contact with grooves (30) of a stopper (28) of the support (1), the housings forming a row of housings, the support defining a channel (16) which places two adjacent housings in fluid communication, the stopper (28) extending from the receiving surface (26) in the extension of the housings in a longitudinal direction (Z) passing through the ends, each groove (30) being associated with a housing, - an insertion of each fiber (60) into one of the housings (3) along an axial direction of the fiber from a proximal end (5) of the housing to a distal end (7) of the housing, the axial direction of the fiber being orthogonal to the stop direction (Y), and - centering of the fiber (60) relative to the housing as it is inserted by means of a flared portion (9) of the housing, the flared portion (9) tapering towards the distal end.

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