Patent ID: 11884789
Assignee: THE BOEING COMPANY
Field: Other special machines (Mechanical engineering)
Classification: CPC C | IPC C

Claim 12:
13. A method of determining a suitability of a prepreg composition for incorporation into a composite structure, comprising:, illuminating the prepreg composition with light of a first wavelength, wherein the prepreg composition comprises:
a bed of fibers disposed in a partially cured resin matrix; and
a plurality of core/shell quantum dots disposed on or in the resin matrix, each quantum dot including an inner core covered by an outer shell;
the inner core being such that when excited by light of the first wavelength the inner core emits a detectable luminescent signal at a second wavelength;
the outer shell being such that it blocks light of the first wavelength from reaching the inner core when the outer shell is intact; and
the outer shell further being such that it degrades upon exposure to UV radiation such that a detection of the luminescent signal at the second wavelength indicates that the quantum dot has been exposed to UV radiation;, detecting the luminescent signal at the second wavelength from the inner core; and, determining a suitability of the prepreg composition for incorporation in a composite structure based upon at least the presence of the detected luminescent signal at the second wavelength.