Direct Optical Initiation (DOI) of explosives offers significant safety advantages over traditional electrical initiation of
explosives, primarily by removing the electrically conducting pathway to the explosive material. A firing system
typically consists of three main components: the fireset, which provides the energy to initiate the explosive; the cable,
which transmits or conducts this energy; and the detonator, which uses this energy to initiate the explosive charge.
Electrical firing systems used to fire secondary explosives typically use voltages of 500 volts and upwards, with currents
of 500 amps and upwards. The technology to transmit such signals over the short distances required is mature and well-proven.
However, an optical initiation system requires optical powers in excess of 10 MW, and the technology to deliver
such powers is relatively immature. Optical fibers are used to transmit the firing energy, which require very high
tolerances to ensure the beam is successfully coupled into the fiber without damage. Fiber optic tapers offer a method to
relax these tolerances, and hence reduce system cost and complexity, by providing a larger area into which to couple this
beam. We present here our initial results from a series of tests aimed at establishing the feasibility of using tapered
optical fibers for this purpose. The transmission loss and beam profiles are reported as a function of the beam position on
the input face of the optical fiber.