Abstract: A flashlight includes a focusing beam assembly which is diposed between an elongate casing holding the batteries and a lens cowl enclosing an open end of the casing. The focusing beam assembly includes a parabolic reflector slidably mounted within a base. A spring urges the reflector forward relative to the base so that a light bulb mounted in the base is normally at a first position relative to the reflector. By tightening the lens cowl on the casing, the reflector can be compressed against the spring relative to the base so that the position of the light bulb relative to the reflector is changed. In this way, the beam width emanating from the flashlight can be adjusted.

Abstract: An improved SCUBA diving gauge. A pictograph display is provided which has a shape which conveys the type of information being displayed. The pictograph has the shape of a SCUBA tank for a tank pressure display and the shape of a person for a display of nitrogen absorbed. Pressure transducers coupled to the SCUBA tank and the external water provided the pressure readings required to produce the respective displays. The differential signal from the transducer is supplied to a processor through an auto-zeroing circuit. The auto-zeroing circuit uses a capacitor initially coupled to an amplifier reference input and single ended output to store an offset voltage. During a measurement, the capacitor is disconnected from the amplifier output and has its other lead coupled to a full scale value of the differential input to produce an output signal which is a ratio.

Abstract: An improved SCUBA diving gauge. A pictograph display is provided which has a shape which conveys the type of information being displayed. The pictograph has the shape of a SCUBA tank for a tank pressure display and the shape of a person for a display of nitrogen absorbed. Pressure transducers coupled to the SCUBA tank and the external water provide the pressure readings required to produce the respective displays. The differential signal from the transducer is supplied to a processor through an auto-zeroing circuit. The auto-zeroing circuit uses a capacitor initially coupled to an amplifier reference input and single ended output to store an offset voltage. During a measurement, the capacitor is disconnected from the amplifier output and has its other lead coupled to a full scale value of the differential input to produce an output signal which is a ratio.

Abstract: A light beam target designator includes a first beam generator and a second beam generator. The beams are aligned so that they may be selectively directed to a common beam deflecting mechanism which allows for deflection of the beams to compensate for windage, distance to target, and the like. Typically, the first beam generator is a visible light laser and the second beam generator is an infrared laser. In this way, a single target designator is provided which is useful both at night and during the day.

Abstract: A hand held spotlight includes a sealed beam enclosure together with one or more detachable handles. The detachable handles each include a latching mechanism capable of translating a magnet between a first position and a second position. A magnetically-actuated switch within the enclosure is used to turn off and on the light circuit. The handle is detachably mounted on the enclosure in a particular position so that the magnetically-actuated switch within the enclosure may be opened and closed by the magnet in the handle. In the preferred embodiments, a single enclosure may be utilized with either a pistol-style grip or a lantern-style grip. The ability to form the beam enclosure without penetrations is particularly useful in providing watertight and explosion-proof spotlights.

Abstract: A safety utility knife includes a handle, a blade fixed to the forward end of the handle, and a retractable sheath which is received within the handle. A mechanism is provided for automatically retracting the sheath within the handle by depressing a single button at the rear of the handle.