Patent ID: 7154081

Claim:
A composite structure comprising: a coated element, and at least one fiber optic condition sensor embedded physically within a coating of said coated element, wherein the at least one fiber optic condition sensor exhibits an initial wavelength at a zero state prior to being embedded physically within the coating, and wherein each of the coating and the at least one fiber optic condition sensor has a coefficient of thermal expansion (CTE) which is sufficiently different from one another so as to induce compressive stress on the at least one fiber optic condition sensor to achieve a wavelength change thereof during a normal state which is greater than about 0.1 nm relative to the initial wavelength of the at least one fiber optic condition sensor at the zero state to thereby achieve a predetermined strain characteristic which is responsive to a selected condition of the composite structure to be sensed, and wherein said sensor detects a change in the predetermined strain characteristic which is indicative of the condition of said composite structure during an abnormal condition due to the induced compressive stress achieved by the different CTE of the coating and the sensor.