An efficient compact star coupler for use in fibre optic transmission systems

Demonstrates the operation of a 19×19 fibre optic star coupler which provides a small, cheap, passive, rugged and reliable component. The principles were tested with readily available components which were reasonably well matched, but not ideally so. The spread ion relative coupling coefficients was rather large at ±2dB, but this would undoubtedly be smaller in an optimized design, and in any case is not necessarily an embarrassment in short-haul applications such as within one vehicle, or between closely-spaced computers, or computer elements such as transputers. Indeed these star couplers are in most respects ideal to realize the interconnections required in many modern parallel electronic computer architectures. In all these potential applications the considerations of compactness, ruggedness and/or reliability may override those of absolute efficiency and uniformity