Laser initiated ordnance fibre=optic continuity test

摘要

A primary light source emits light at a primary wavelength. A test light source emits light at a test wavelength. The test wavelength is different from the primary wavelength. Light is directed from the primary light source into a first end of the optical fibre. Light is directed from the test light source into the first end of the optical fibre. Light from either the primary light source or from the test light source is alternately interrupted. A coating is mounted on the second end of the optical fibre, having the property of transmitting light of the primary wavelength and also reflecting light of the secondary wavelength. The test light source is pulsed and pulses of light from the test light source which are directed out of the first end of the optical fibre are detected after they are reflected by the reflective and transmissive member. The intensity of the light pulses detected can be measured, so that a discontinuity in the optical fibre can be sensed by a reduction in the intensity of the reflected light pulses.