This invention is directed to a fiber optic bulkhead fitting wherein the optical fiber can be optically coupled through and soldered to a bulkhead.
Optical fibers are suitable for the transmission of digital information and are being increasingly used for that purpose. Optical fibers are superior to the employment of electrical conductors for a number of data transmission needs. However, there has been a problem in passing an optical fiber from one environment, through a bulkhead, to another environment because of the problems of reliably sealing the optical fiber to the bulkhead. Such sealing is necessary to provide sure separation between the spaces separated by the bulkhead. Accordingly, there is need for a bulkhead fitting which is compatible with both the optical fiber and the bulkhead to provide complete and reliable sealing.
Previous attempts at running an optical fiber through a bulkhead and sealing it with respect thereto have been unsatisfactory because of the microbending losses. When epoxy is used to seal an optical fiber with respect to a structure like a bulkhead, the forces on the optical fiber cause local changes in the index of refraction which is the microbending loss. With epoxy, the loss is about 1 decibel. This is a significant loss in such a system and cannot be tolerated in any but short, simple systems.