Process and apparatus for elimination of tolerance dependent variations of a selectable spacing between components in optical communication equipment

#1. Field of the Invention

#The present invention relates to a process and a device for eliminating tolerance-dependent variations of a preselectable space between the components used in optical communication equipment. More specifically, the invention relates to a process for eliminating tolerance-dependent variations of a preselectable space existing between at least two optical communication components which are arranged parallel to each other. The components are provided with a flange-type neck, and are respectively fixed with the neck at right angles to their longitudinal extension in a U-shaped recess of a wall of a casing which is provided for jointly accommodating at least two components.

#2. Description of the Prior Art

#FIG. 1 shows the wall of a metal casing provided with U-shaped recesses and the flange-type necks of a transmitting and receiving module of an optical communication device located in the recesses;

#FIG. 2 shows a flange-type neck of a transmitting and receiving module without the casing of the neck, and

#FIG. 3 through FIG. 6 show various embodiments for encasing a neck with a plastic deformable material.

#FIG. 1 illustrates a metal casing 1 provided with a wall 2, both of which are so worked into the U-shaped recesses 3 that the recesses 3, which are similarly dimensioned, are open toward one edge 4 of the wall 2. The lateral walls 5 of the U-shaped recesses 3 are provided with ribs 6 which extend from the open end of the U-shaped recess to the enclosed end of the recess and, at the same time, run parallel to the wall 2. The ribs 6 thus reduce the space between the lateral wall 5 of each U-shaped recess.

#Two components 7 of an optical communication equipment, preferably a transmitting and receiving module, respectively, are provided with a prismatic casing which has the advantage of having similar dimensions for both modules and is provided internally with an electro-optical or optoelectrical converter as well as other circuit components, e.g., amplifiers or the like. At one front end 16 of the component 7 they are provided with a flange-type neck 8, preferably made of metal and penetrated by a longitudinal borehole 9. This forms the neck 8 of a bushing into which a pin can be inserted. A light-conducting fiber inserted into the pin (not shown) may thus be coupled with a component which is arranged in the component 7 and either converts the light signals arriving via the fiber into electrical signals or, alternatively, may convert the electrical signals fed to the component 7 into optical signals, and then feed the signals into the fiber.

#Two matching components 7 (for example, a transmitter and receiver) are arranged at a precise distance 10 from each other, so that, e.g., when electrically connecting the components 7, the joint insertion of the connecting pins projecting from the components 7 into the grid-type boreholes of a printed circuit board is not obstructed. The space 10 between the two components 7 is determined by the fixing of the necks 8 in the U-shaped recesses 3 of the casing wall 2.