SBIR-STTR Award

Demonstrate a fourier (laser diffraction) inspection method for detecting pinholes in hermetic coatings of optical fibers. Fourier methods have been successful in detection and counting objects in the size range (0.01 to 20 microns) of anticipated pinhole defects. This method is non-contacting, non-destructive, and will not interfere with the optical fiber drawing process. Formulate a draft set of standards to evaluate effectively of pinhole detection methods. Compare this new method to present methods. Work undertaken shall include: (I) research state-of-the-art methods. (II) formulate draft evaluation standards. (III) perform experimental demonstration (proof-of-principle) of fourier (laser diffraction) inspection for pinholes in hermetic coatings via an existing instrument developed and manufactured by the proposer, tai, inc. (IV) create a plan to develop and test a fully functional production inspection system based upon tai's instrument for installation at a manufacturing facility for phase ii. Describe plan to commercialize this system across a broad segment of optical fiber manufacturing. The type of system we propose will detect problems in-process allowing not only inspection but timely correction of problems. If hermetic coating application, now desirable, becomes universal by becoming readily and thoroughly verifiable, the value of systems making this possible becomes very high.

In Phase I of this project a method for inspecting and detecting pinholes in hermetically coated fiber was demonstrated. The instrument was in-line, non-destructive, non-contacting, real-time, and did not alter the present manufacturing process. Some modifications and enhancements to the system are planed for Phase II. All of the objectives of phase I were not only met but the experimental work went far beyond the scope of work. The on-site experimental work at the fiber manufacturing facility gave insight to needed modifications and enhancements. For Phase II of this project a fully functioning monitoring and inspection system is to be installed on a drawing tower ready for production of commercially available hermetically coated optical fiber that has been 100% inspected. Coordination with existing government programs that have a need for hermetically coated optical fibers is planed as a portion of the Phase II scope of work. With the modifications and enhancements implemented, the system developed for this project will open new doors for not only the manufacturers of optical fiber but the end user as well. Once it is shown that the hermetically coated fiber can overcome many of the difficulties encountered by the end users, such as salt water degradation, hydrogen ion erosion, and shelf-life degradation. Both military and commercial applications (including high reliability data links, sensors, controls, and environmental monitoring, etc.) can benefit from this endeavor tremendously.