Abstract: An in-line fiber optic connector has a pair of ferruled components having rrules enclosing optical fibers. The optical fibers are connected by placing the faces of said ferrules in abutment with each other inside a split tube. Threaded components that abut the ferruled components bring the faces of the ferrules together by being threaded to each other. This enables the compression between the faces of the ferrules to be closely controlled.

Abstract: An adaptive optics wavefront control system is presented wherein phase errors are reduced to a minimum using a coarse/fine gradient sensor.

Abstract: A distance measuring device transmits a continuous alternating wave from a wave source to a target which reflects it back toward the device. The wave source is activated until such time that a detector associated with the device senses the beginning of the reflected wave at which time the wave source is deactivated. The wave source is deactivated during the time that the reflected wave is sensed by the detector and upon the sensing of the end of the reflected wave, the wave source is again activated. The frequency at which the wave source is alternately activated and deactivated is a measure of the distance between the measuring device and the target.

Abstract: An electromagnetic actuator used with a segmented optical element includes a central pole piece that is affixed at one end to the segment, and is movable along a displacement axis. Oppositely wound, longitudinally displaced electical coils on the pole piece are encompassed by an outer magnet. Pole piece displacement is the result of the net axial force generated from the current flowing through the coils.

Abstract: An extendable large aperture phased array mirror system includes a plurality of mirror segments cooperatively configured to receive an incoming electromagnetic beam. In response to signals from a sensor indicative of wavefront distortion in the beam, a control apparatus displaces a plurality of segment actuators to configure the mirror segments to generate an outgoing conjugate phase electromagnetic beam.

Abstract: An inductive displacement sensor includes an oscillator circuit that is characterized by primary and secondary pairs of coils disposed on opposing surfaces of adjacent optical segments. Each coil in both coil pairs is alternately positioned along a respective axes perpendicular to a segment displacement axis. The secondary coils are respectively tuned to frequencies above and below the oscillator circuit resonant frequency. Any motion between segments along the displacement axis induces a detectable change in phase between the current and voltage of the oscillator signal.

Abstract: A constant length strut includes an axially elongated body having a fixed attachment point at one end and an attachment point carried at its opposite end and supported for axial movement toward and away from the fixed attachment point. A quartz reference rod is connected at one end to one attachment point and extends internally for substantially the length of the strut. The free end of the reference rod moves axially lengthwise relative to the other attachment point as the strut changes length due to thermal expansion and contraction or tensile and compressive loading. A positional displacement transducer senses this relative movement. An electrical signal directly proportional to the displacement excites a linear actuator connected between the telescopic attachment point and the strut body to provide a corrective displacement to maintain the strut at a constant length.