Master Bond EP29LPSP epoxy adhesive was cited in two patent grants for ways to improve the performance of fiber-optic gyroscopes (FOGs) through unique designs of the fiber-optic sensing coil apparatus, which is at the heart of a FOG.

In the first patent, granted to Honeywell International Inc., the sensing coil apparatus consists of an optical fiber formed into a coil and placed inside an oxygen-filled hermetically sealed chamber.1 The fiber-optic coil is held together with an adhesive, which also serves to fill gaps between the coil windings and to provide a smoother surface for winding successive layers of the optical fiber. Master Bond EP29LPSP two-part epoxy is identified in the patent description as a suitable adhesive for this application.

The second patent, issued to Morgan Research Corporation, describes a method of winding the coil so as to eliminate fiber winding crossovers and time-varying thermal gradients, which can degrade FOG performance.2 Multiple coil layers are wound in opposite directions, and perforated separators are placed between them. A potting compound is applied to the first coil layer and, when the perforated separator is added, excess potting compound squeezes through the perforations and is used as an adhesive during the winding of the second coil layer. Master Bond EP29LPSP is cited as an appropriate potting compound for this application.

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1Chappell, Charles D. and Kara L. Warrensford.“Systems and methods for controlling the gas conversion in a fiber-optic gyroscope.” US Patent 9,182,230. 10 November 2015.
2Williams, Marty R. “Crossover-free fiber optic coil sensing and winding method.” US Patent 7,477,806. 13 January 2009.