Crystals formed of a solid-solution of Ni(BF.sub.4).sub.2 6H.sub.2 O provide very good materials for filtering ultraviolet light and will not deteriorate in temperatures as high as 110.degree. C. They are particularly useful in sensing devices which seek to identify the presence of ultraviolet light in the UV missile warning band.

A logic and memory circuit with reduced input-to-output signal propagation delay includes signal processor and memory elements connected in parallel for performing "memory work" simultaneously with "logical work" and/or "electrical work." Incorporated within a flip-flop having master and slave latches which perform the memory work (i.e. data storage) on the input and output logic signals, respectively, is a signal processor which processes one or more input signals to provide an output signal. Where memory work and electrical work are to be performed simultaneously, the signal processor includes a serial group of circuits having successively larger transistors for buffering an input signal to provide the output signal simultaneously with the storage of the input and output signals by the master and slave latches, respectively. Where memory work and logical work are to be performed simultaneously, the signal processor includes a logic function circuit (e.g. a logic gate) for logically processing one or more input signals to provide the output signal simultaneously with the storage of the input and output signals by the master and slave latches, respectively.

A dome assembly (50) adapted for use with a missile (32) having a longitudinal axis (42) parallel to a thrust vector thereof. The inventive dome (50) includes a crystal (30, 50) having a crystallographic structure that includes a plurality of planes (12, 14, 16), one of said planes (14) being more susceptible to failure than one or more of the other planes (12, 16). A surface around a missile sensor provides a place for mounting the crystal (30, 50) so that said plane susceptible to failure (14) faces approximately opposite to that of a positive velocity vector (34) of said missile (32). In a more specific embodiment, the crystal (30, 50) is a sapphire crystal (30, 50) having a crystallographic structure that includes positive n-planes (12), positive r-planes (14), and a c-plane (16). By design at nominal conditions, an r-plane (14) is approximately bisected by a plane formed by the normal of the c-plane (16) and a wind flow vector (36) parallel to a thrust vector of said missile (32). A turntable (not shown) orients the sensor dome (50) so that a first r-plane (14) faces leeward of impinging airflow (36) corresponding to the wind flow vector (36). An r-plane normal (38) of a second r-plane forms an angle of approximately 60 degrees with respect to impinging airflow (36) that is approximately parallel to the thrust vector of the missile (32). The turntable includes a motor (not shown) for strategically orienting the lattice planes (12, 14, 16) of the dome (50) so as to maximize the strength of the dome (50) with respect to applied stresses.

The present invention relates to process for producing a transparent missile dome having a spanning angle larger than 180.degree., comprising the step of: (a) growing from single crystals of a ceramic material a first dome portion, said first dome portion being a portion of a sphere (b) growing from single crystals of a ceramic material a second dome portion, said second dome portion being a complementary sphere-portion for said first dome portion (c) attaching said complementary dome portion to said first dome portion and to the body of the missile, thereby forming a missile with a front dome having a spanning angle larger than 180.degree..

Missile deflector systems for protecting a vehicle from threats that use an infrared sensor for guidance are disclosed. An exemplary missile deflector system can include, for example, a radiation source and one or more deployable smart chaff elements. The light source and the one or more deployable smart chaff elements can direct the threat, such as, for example, a missile, away from the vehicle or, in other embodiments, disable the threat. Another exemplary missile deflector system can include, for example, a smart chaff element with a near-infrared emitter and a plurality of transmitting fibers to transmit the near-infrared radiation out of the smart chaff element.