Multi Stage Fibre Optic Probes

Abstract

Fibre optic probes easily can be placed on high explosive charges. Thus the detonation front can be observed while breaking through the surface of the charge. By inser ting those probes in a high explosive charge, this technique can be extended to a diagnostic tool for observation detonation phenomena inside the charge. Arrival time at the tip of the probes can be measured simultaniously to the break-through of the detonation front at the outer surface of the charge when a streak camera is used Each of the light fibres can transduce one light pulse only If there is need for observation in several planes of the high explosive charge the number of probes has to be increased to an amount which however causes severe disturbance of the detonation wave propagation. The detonation wave can be observed in a multi-planar way by means of a new probetechnique avoiding the disadvantage mentioned above. The light fibre probe now has several airgaps placed appropriately along the probe, each of them giving an output of light at the end of the probe when the detonation wave propagates down the probe. Thus by multiplanar diagnostic of the detonation wave inside a high explosive charge it is possible to measure the detonation front with comparatively small disturbances and little effort. Practicable solutions for the set-up of the light fibre probes are discussed and the advantage of this technique is demonstrated on examples.