NZ206164A - Device for aligning optical fibre cable ends - Google Patents

Description

Priority Date(e); /"5 ; 3 p? Complete Specification Filed: 4a Class: Ir.l&MLI . .Qj.QiSS./.QQ..

Publication Date: ... Fl.l.JUN .19861.... P.O. Journal, Wo: ... .............

ORIGINAL $ c ,r^ f MfflVf# " 4 ^ NEW ZEALAND THE PATENTS ACT, 1953 COMPLETE SPECIFICATION "A SPATIAL DISPLACEMENT DEVICE" WE,. INTERNATIONAL STANDARD ELECTRIC CORPORATION, a Corporation of the State of Delaware, United States of America, of 320 Park Avenue, New York 22, New York, United States of America, hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement 206164 This specification discloses a device for antibacklash adjustment of objects. An embodiment employing two-dimensional displacement will be described.

One such device is known which substantially consists of a 5 ladderlike frame comprising three crosspieces of which the centre one has two bearing points on which a first rocker rests. One end of the rocker is compression-spring loaded while the other rocker end is pressed resiliently against an adjusting screw seated in a coverplate of the frame. The first rocker covers a bridge-like 10 upper part. Between this upper part and the lower part likewise comprising bearing points, there is provided a second rocker containing the object to be adjusted, with the one end of this rocker likewise being compression-spring loaded and with the other end thereof again being pressed resiliently against an adjusting screw 15 associated therewith, which is seated in the upper part of the first rocker. It is an object of the present invention to provide a device which comprises a minimum number of simple individual parts which can be manufactured in a particularly economical manner .

This specification discloses a spatial displacement device comprising a baseplate, an intermediate plate resiliently piv-otally attached thereto via a first hinge means and having a first adjusting screw in threaded engagement with either the intermediate plate or the base-plate and in reactive engagement with the 25 base-plate, or intermediate plate respectively, the first adjustment screw being displaced from the axis^of first hinge means, a 206164 support plate resiliently plvotally attached to the intermediate plate via a second hinge means and having a second adjusting screw in threaded engagement with either the support plate or the intermediate plate and in reactive engagement with the intermediate plate or support plate respectively, the second adjustment screw being displaced from the axis of the second hinge means, and the second hinge means being displaced in the plane of the intermediate plate from the first hinge means.

Various advantages are achievable with the device. It has displacement paths which are within the range extending from micrometers to millimeters. Therefore, objects can be positioned very exactly. Precision parts are not required for this purpose. Even when the device comprises a baseplate having a ground (polished) surface and a cylindrical rod, it is sufficient to adhere to the usual manufacturing tolerances, because neither the thickness nor the diameter are critical. The device is mechanically robust as well as insensitive to soiling. It is practically not subjected to any wear and, therefore, has a long 3 0 2061 6' service life. Further advantages are set forth in the specification.

The invention will now be explained as follows with reference to examples of embodiment shown in Figs. 1 to 5 8 of the accompanying drawings, in which: Fig. 1 shows a device with a receptacle for adjusting optical fibres, in a front view, Fig. 2 shows a device designed as a splicing connector with fibre-optic cables fixed therein, in a side view, 10 Fig. 3 is the sectional view of the device taken along the line A-A of Fig. 2, in a perspective representation, Fig. 4 is the cross-sectional view of the device taken on line A-A of Fig. 2, Fig. 5 shows a device designed as a plug-and-socket 15 connector with a fibre-optic cable fixed therein, in a perspective representation, Fig. 6 shows the device of Fig. 5 as inserted into a socket, partly in a cross-sectional view, Fig. 7 shows the device as inserted into an optical 20 attenuator, with connected fibre-optic cables, partly sectionally, in a sideview, and Fig. 8 shows the device in the optical attenuator as shown in Fig. 7 with a cross-sectionally shown cover, in a front view.

The device as schematically shown in Fig. 1 consists * ;206164 ;substantially of three spaced and hingedly connected rectangular plates and two adjusting screws. The lowest first plate serves as the baseplate 1 which, via a first hinge 2 provided for within the area of one longitudinal side, is connected to the second plate 5 disposed thereabove, representing an Intermediate plate 3. This intermediate plate 3, within the area of the longitudinal side lying opposite the one of the previously mentioned hinge 2, is connected to a third plate disposed thereabove, via a second hinge 4, with this third plate serving as the supporting plate 5-10 In the intermediate plate 3 there Is seated an adjusting screw 6 acting against the baseplate 1, and in the supporting plate 5 there is seated a further adjusting screw 7 acting against the intermediate plate 3. Each adjusting screw 6, 7 is disposed within the area of the longitudinal sides of both the intermediate 15 plate and the supporting plate 3, 5 lying opposite the hinges 2, ;4. ;For an object to be positioned, a supporting plate 5 Is provided with a receptacle 8 which, for example, is designed as a V-shaped groove for inserting an optical fibre, or else as a recess 20 for inserting the housing of an optoelectronic component. ;In order to obtain maximum adjustment, an embodiment of the device in which the paths along which the object is to be displaced is chosen to resemble as closely as possible those of orthogonal movement. Therefore, both the object and the hinge 25 axes are positioned in such a way that the co-ordinates thereof form the corner points of a right-angled triangle, with an imagi- ;K.z. Lr i-icp S ;imu 198b ;RECEIVED ;5 ;0 ;15 ;•° ;206164 ;nary line between the hinge axes forming the hypothenuse of the triangle. For this reason, in all examples of embodiment of the displacing device, the movable second hinge 4 is disposed in the apex of the angle and the stationary first hinge 2, is disposed in the apex of the angle . Moreover, the object receptacle is so designed that its centre line, coinciding with that of the object to be adjusted, will come to lie almost in the apex of the right angle . The hinges 2, 4 and the receptacle 8 for the object are preferably disposed in such way that the hinges and the centre line of the object receptacle are staggered in relation to one another in both the horizontal and the vertical directions. Upon actuating the fine-thread adjusting screws 6, 7, both the intermediate and the supporting plates 3, 5 are hinged and an object (specimen) fixed in the receptacle 8, is displaced in the course of this, in the direction of both X and Y co-ordinates. ;In the device as shown in Fig. 1, the baseplate, the intermediate plate and the supporting plate 1, 3, 5, as well as both hinges 2, 4 consist of one single part. The individual plates are in this case partly separated from one another by way of slots formed therein, with the remaining land portions therebetween forming the hinges. ;The device as shown in Figs. 2 to 4 is capable of being used in an arrangement for establishing spliced connections, from which a fibre-optic cable 10, 10' is removed after its fibre ends have been spliced. The device, however, may also itself form part of the splice, with optical fibres 11, 11' remaining permanently ;266164 ;fixed in the device. Here, both the intermediate plate 3 and the supporting plate 5 are disposed at the end of an extended baseplate 1 the other end of which is provided with an attachment 9. This attachment 9 contains a receptacle with a fibre-optic cable 10' detachably fixed therein, with the optical fibre 11' thereof being almost in axial alignment with the optical fibre 11 of the fibre-optic cable 10 detachably fixed in the supporting plate 5. ;In the device the hinge 2 connecting the baseplate 1 to the intermediate plate 3 consists of a mechanically stable flat spring plate which, by employing the usual connecting techniques, is secured to the longitudinal sides of the aforementioned plates 1, 3. The hinge 4 connecting the intermediate plate 3 to the supporting plate 5 likewise consists of a simple spring plate which, however, is designed as an angle bar which is secured with one leg to the intermediate plate 3, and, with the other leg, to the longitudinal side of the supporting plate 5 which is of a more narrow design. ;The attachment 9 and the supporting plate 5, as well as the intermediate plate 3 are sufficiently spaced from one another so that the ends of the optical fibres 11, 11' projecting from each cable, and following the exact axial alignment thereof, can be fused to one another and removed from the device thereafter. In cases where the facilities necessary for the fusing of the fibre ends are not available, such as during field-trial use, the fibre-optic cables 10, 10' can remain in the device. For improving lightwave transmission, however, either an immersion liquid or a ;N.Z. PATENT OS *'3-1- 2 4 JAN 1936 7 RECEfVCO t 2061$4 transparent adhesive may be applied to the end faces of the fibres. Such connections have low coupling losses, because the fibre ends are capable of being aligned core to core. Owing to the high positioning accuracy, the device is not only suitable for 5 connecting graded index fibres, but also monomode fibres.

The example of embodiment of the device shown in Pig. 5 and 6, is designed for establishing plug-and socket connections.

There is used an angle bar one leg of which forming the baseplate 1. This baseplate 1 is topped by the intermediate plate 3 and the 10 supporting plate 5 in the form of receptacle 8 in which the op tical fibre 11 is fixed. The hinges 2, 4 of both plates 3, 5 each consist of a rectangularly bent spring plate. The other leg 12 of the angle bar preferably standing rectangularly upright from the baseplate 1, is of shorter width. The outer side thereof and the 15:: bottom side of the baseplate 1 have ground (polished) surfaces which, in the course of establishing plug-and-socket connections, serve as reference surfaces.

The connector socket 13 as shown in Pig. 6, which is designed for holding and mutually aligning two insertable plug-and-socket 20 devices, consists substantially of a flat baseplate 14 with a ground (polished) surface and a cylindrical rod 15 mounted thereto along one longitudinal edge. The surface of the baseplate 14 and the ground (polished) jacketing surface of the rod 15 serve as complementary reference surfaces and lines for the plug-and-socket 25 devices. Against these the plug-ang-socket devices as inserted from opposite sides, are retained with the aid of suitable spring ■'ATE.VT OFFICE MAR 1986 RECEIVED 206164 elements 16, 17- Appropriately, on the cylindrical rod 15 of the connector socket 13 there is mounted for each plug-and-socket device one separate spring element 16 which, with its spring end, presses from above onto the vertical leg 12 of the plug-and-socket device. Similarly, on the baseplate 14 of the connector socket 13, likewise two separate spring elements 17 are mounted which each press against the other free longitudinal edge of the baseplate 1 of the plug-and-socket device.

Such a connector offers the advantage that each of the connector halves may comprise an adjusting device with the aid of which the optical fibre can be aligned. In this way the connector halves are interchangeable without having to be readjusted. The individual parts of the connector are simple to manufacture and to assemble. The formerly necessary threading of the optical fibres into sleeves or narrow-tolerance drill holes can be omitted, because the fibre, without causing any danger of its end face being upset or damaged, is only inserted into an open groove and can be easily fixed therein owing to the direct accessibility. This can be performed with the aid of a simple bonding method requiring no vacuum for drawing adhesive through a drill hole. Moreover, the adhesive joint can be easily inspected with for any voids, bubbles or blisters therein, thus permitting easy quality control. Considering that a fibre with a previously prepared end face can be located in the receptacle of the plug-and-socket device (connector), the otherwise subsequently required grinding and polishing of the end face of the fibre can be omitted. Moreover, the end 206164 face of the fibre can be set back by a few ym from the front edge of the connector, so that in the plugged-in state, a direct contact between the two end faces of the fibres is avoided. Since the adjusting screws, owing to the usually pretensioned hinge 5 springs, are capable of being moved without any backlash, no maladjustment will occur during the fixing of the fibre position.

Of course an arrangement similar to Pig. 2 could also be used in which only one of the connector halves is adjustable.

In Pigs. 7 and 8 the device is shown to form an integral part 10 of an optical attenuator built up on a base 18 with a removable cover 19. In the base 18 there is supported a shaft 20 which is capable of being rotated from the outside with the aid of a screwdriver. The shaft 20 is provided with a collar 21 which serves as a limit stop and for guiding a disc-shaped ambient or optic 15 lightfilter 22 which, distributed in the circumferential direc tion, comprises a number of zones 23 with neutral density (grey) filters of different attenuation.

This optic light or neutral density filter 22 is disposed in about the centre of the base 18, one half of which carrying the 20 device. The baseplate 1 of the device is firmly connected to the base 18, but may also consist of the base itself. In that case, the intermediate plate 3, via the spring plate serving as the hinge 2, is connected directly to the base 18.

The other half of the base is shown to carry an attachment 24 25 with a V-shaped receptacle groove and a fibre-optic cable 10' fixed therein whose optical fibre 11', which has been stripped of IV Z. r Vri'i'.T OFFICE I 7MA21986 10 RECEIVED 206164 its outer cable sheathing and which is provided with a spherical lens at its end face, is almost in axial alignment with the optical fibre 11 as clamped in the device, and which, at its end face, is likewise provided with a spherical lens. With the aid of the displacement or adjusting device, the fibre axes can now be very exactly brought into axial alignment with one another, so that the stepwisely or, if so required, continuously variable attenuator will show to have an extremely small fundamental attenuation . 11

Claims (13)

What we claim is:-

1. A spatial displacement device comprising a baseplate, an intermediate plate resiliently plvotally attached thereto via a first hinge means and having a first adjusting screw in threaded engagement with either the intermediate plate or the baseplate and in reactive engagement with the base plate or intermediate plate respectively, the first adjustment screw being displaced from the axis of the first hinge means, a support plate resiliently plvotally attached to the intermediate plate via a second hinge means and having a second adjusting screw in threaded engagement with either the support plate or the intermediate plate and in reactive engagement with the intermediate plate or support plate respectively, the second adjustment screw being displaced from the axis of the second hinge means, and the second hinge means being displaced in the plane of the intermediate plate from the first hinge means.

2. A device as claimed in claim 1, including an object receptacle, and wherein the axes of the first and second hinge means and the centre line of the object receptacle are staggered in relation to one another in both the horizontal and the vertical direction.

3. A device as claimed in claim 1 or 2, wherein the first and second hinge means consist of springplates.

4. A device as claimed in claim 1 or 2, wherein the baseplate, the intermediate plate and the supporting plate and the first and second-hinge means consist of one slotted part. _ PATENT 0; 2 4 JAW 3986 1 2 206164

5. A device as claimed in any one of claims 2 to 4, wherein an extended portion of said baseplate carries an attachment provided with a receptacle for a fibre-optic wave guide which is approximately in alignment with the object receptacle contained in said supporting plate.

6. An optical fibre splicing device including a spatial displacement device as claimed in any one of claims 1 to 5-

7. A device as claimed in any one of claims 1 to 4, wherein the base plate consists of an angle bar both legs of which have ground or polished surfaces on the outside.

8. An optical fibre connector comprising a spatial displacement device as claimed in any one of claims 1 to 5 or claim 7.

9. An optical fibre connector as claimed in claim 8, comprising a carrier plate with a cylindrical rod mounted fixed along one longitudinal edge thereof, and at least a first spring element secured to said rod which, when a plug-and-socket connector is mounted on said carrier plate, resiliently engages a vertical leg of said plug-and-socket connector, and at least a second spring element which is secured to the said carrier plate which resiliently engages an upper free longitudinal edge of a horizontal leg of the plug-and-socket connector.

10. A spatial displacement device as claimed in claim 5, including an adjustable optical filter part of which is interposed between said receptacle for a fibre optic waveguide and said object receptacle, for filtering light transmitter via said fibre N.2. rATSOT RECEIVED 13 206164 optic waveguide and a fibre optic waveguide located in said object receptacle.

11. A device as claimed in any one of claims 1 to 5i wherein the effective pivotal axes of the first and second hinge means and a point to be displaced form a substantially right-angled triangle with the point to be displaced at the apex of the right angle.

12. A spatial displaclement device as herein described with reference to the accompanying drawings.

13. An optical attenuator as herein described with reference to the accompanying drawings. INTERNATIONAL STANDARD ELECTRIC CORPORATION P.M. Conrick Authorized Agent P5/1/1466 i N,2. LATENT 0? 2 4JAN19S6 RECEIVED 14