Abstract: A laser diode apparatus for initiating explosives or other pyrotechnic devices that has capability of checking both the laser diode operation and the optical fiber continuity between the laser diode source and the explosives required to be detonated. Power isolation circuits are provided to control the flow of current to the laser diode, also isolation filters are used to allow only the command signals to initiate the firing circuits employed.

Abstract: An RF laser array driver apparatus with a DC bias input and and RF input to modulate a diode array and provide a modulated optical output. The driver circuit comprises a series impedance which is in parallel with the diode array to provide a 50 ohm impedance to the RF input signal that is substantially constant with frequency.

Abstract: Broadband electrooptical modulator means for use in optical and electrooptical communication systems and the like, the modulator means including modulator driver and driver amplifier means, broadband matching network means, temperature control means, and means to automatically compensate for variations including electronic variations in the output. The subject modulator means employ optically coupled crystal elements which have their optical Z-axes oriented perpendicularly to each other to cancel natural birefringence and to reduce temperature sensitivity including the temperature sensitivity of the extinction ratio of the crystals.