Lateral offsets for multimode fiber MMF connectors part

Lateral offsets for multimode fiber (MMF) connectors part 1 Al Brunsting & Rick Pimpinella Panduit Corporation 17301 Ridgeland Avenue Tinley Park, IL 60477 Voice: 708 -532 -1800/888 -506 -5400 Fax: 708 -532 -1811 www. panduit. com December 13, 2004 Panduit Corp. 1

Background Simulations for connector lateral offsets are required to specify maximum connector insertion loss. A worst-case MMF lateral offset of 7. 0 m is currently being used. Based on a large comprehensive set of ferrule measurements and fiber specifications, we calculated connector lateral offsets using probability density functions (PDF). From this study it can be assumed that at least 95% of the lateral offsets in the field are less than or equal to 6. 0 m. December 13, 2004 Panduit Corp. 2

Simulation theory Vectors for lateral offsets of a MMF connector (not to scale). December 13, 2004 Panduit Corp. 3

Simulation theory (cont. ) Resultant vector, S, is the sum of its 3 component vectors S = S 1 + S 2 + S 3 S = simulated lateral offset for one of the two connectors in a MMF connection. Component offsets and connector rotations are accommodated in this simulation. x and y components of S: Sx = |S 1| + |S 2|cos 2 + |S 3|cos 3 Sy = |S 2|sin 2 + |S 3|sin 3 From Slide 2 x-y coordinate system chosen so that 1 = 0. December 13, 2004 Panduit Corp. 4

Simulation theory (cont. ) 2 & 3 independently take on 6 values of 0 , 60 , 120 , 180 , 240 , & 300. Mean and standard deviation (SD) for each of |S 1|, |S 2|, & |S 3| come from Panduit measurements and MMF spec. (TIA/EIA 492 AAAA-A, January 1998, Table 1). There are 5 indep. variables ( 2, 3, |S 1|, |S 2|, & |S 3|). For each simulation there are 6*6*5*5*5 = 4500 resultant vectors, (S). Each S will have a statistical wt. Distribution of S‘s & associated wts. give final lateral offset PDF for one connector. Multiply offsets by SQRT(2) to simulate two connectors (one connection). December 13, 2004 Panduit Corp. 5

Simulation theory (cont. ) SD for |S 2| has 3 RMS components: 1. Measured ferrule ID SD. 2. Specified MMF cladding diameter OD. 3. Secondary effects: specified cladding non-circularity & alignment sleeve (est. from Panduit measurements). All taken to be 0. 50 m. Each magnitude (|S 1|, |S 2|, |S 3|) has 5 values (Sa, Sb, Sc, Sd, Se) = (mean – 2*SD, mean – SD, mean + 2*SD). Correspond. stat. wts. (wi) = (0. 135, 0. 607, 1. 000, 0. 607, 0. 135). December 13, 2004 Panduit Corp. 6

An example Consider Supplier 2 & 1 case of 4500 simulated cases: Angles: 2 = 120 , 3 = 240 |S 1| = 0. 14 m (mean – 2*SD), w 1 = 0. 135 |S 2| = 0. 59 m (mean – 2*SD), w 2 = 0. 135 |S 3| = 1. 00 m, w 3 = 0. 607 (mean + SD) Results: Total stat. Wt. = 0. 135*0. 607 = 0. 011 From Slide 4: Sx = -0. 655, Sy = -0. 355, |S| = 0. 745 m. December 13, 2004 Panduit Corp. 7

Values for |S 1|, |S 2|, & |S 3| Note: (|S 1|, |S 2|, |S 3|) depends on (ferrule only, ferrule & MMF, MMF only). Sa 0. Tolerances for MMF are assumed to be at 3*SD. Some measurements, dimensions, and tolerances must be divided by 2 to convert from diameter to radius. December 13, 2004 Panduit Corp. 8

Panduit measurements. (Eccent. , OD, ID) are (eccentricity, outside diameter, inside diameter) m N = no. of ferrules measured. The three middle columns give mean SD. 3050 ferrules were measured. December 13, 2004 Panduit Corp. 9

Lateral offset PDF. Simulation giving the relative probability that the connection has a give lateral offset, |S|. Cumulative frequency is more useful for conclusions. December 13, 2004 Panduit Corp. 10