A system for measuring thermal degradation of composites, the system comprising: a housing having an interior with an opening shaped to expose a test area of the composite to be tested to the interior; a light-emitting diode that emits primarily ultraviolet radiation, the diode mounted on the housing to direct the ultraviolet radiation into the interior and through the opening; an image sensor mounted on the housing and open to the interior to receive radiation emitted from the test area passing through the opening into the interior; wherein the housing includes a side wall, an upper wall attached to the side wall, and a lower wall attached to the side wall, the side wall, the upper wall and the lower wall defining the interior of the housing; wherein the light-emitting diode is mounted in the side wall; the image sensor is mounted in the upper wall; and the opening is formed in the lower wall; wherein the housing includes a first reflective surface positioned in the interior that is shaped and positioned to receive the radiation emitted from the test area and reflect the radiation emitted from the test area to the image sensor and a second reflective surface mounted in the interior and positioned to receive the ultraviolet radiation from the light-emitting diode and reflect the ultraviolet radiation to the opening in the housing; wherein the first reflective surface includes a first parabolic mirror mounted on the upper wall and a second parabolic mirror mounted on the lower wall; the first and the second parabolic mirrors shaped and positioned such that the first parabolic mirror receives the radiation emitted from the test area and reflects the radiation emitted from the test area to the second parabolic mirror; and the second parabolic mirror is shaped and positioned to reflect the radiation emitted from the first parabolic mirror or the test area to the image sensor; and an image processor connected to receive a signal from the image sensor, wherein the image processor is configured to determine a presence or an absence of thermal degradation of the test area in response to the signal. a housing having an interior with an opening shaped to expose a test area of the composite to be tested to the interior; a light-emitting diode that emits primarily ultraviolet radiation, the diode mounted on the housing to direct the ultraviolet radiation into the interior and through the opening; an image sensor mounted on the housing and open to the interior to receive radiation emitted from the test area passing through the opening into the interior; wherein the housing includes a side wall, an upper wall attached to the side wall, and a lower wall attached to the side wall, the side wall, the upper wall and the lower wall defining the interior of the housing; wherein the light-emitting diode is mounted in the side wall; the image sensor is mounted in the upper wall; and the opening is formed in the lower wall; wherein the housing includes a first reflective surface positioned in the interior that is shaped and positioned to receive the radiation emitted from the test area and reflect the radiation emitted from the test area to the image sensor and a second reflective surface mounted in the interior and positioned to receive the ultraviolet radiation from the light-emitting diode and reflect the ultraviolet radiation to the opening in the housing; wherein the first reflective surface includes a first parabolic mirror mounted on the upper wall and a second parabolic mirror mounted on the lower wall; the first and the second parabolic mirrors shaped and positioned such that the first parabolic mirror receives the radiation emitted from the test area and reflects the radiation emitted from the test area to the second parabolic mirror; and the second parabolic mirror is shaped and positioned to reflect the radiation emitted from the first parabolic mirror or the test area to the image sensor; and an image processor connected to receive a signal from the image sensor, wherein the image processor is configured to determine a presence or an absence of thermal degradation of the test area in response to the signal.