Abstract: A system for analyzing smoke has a plurality of units, wherein each unit includes an optical emitter for alternately directing horizontally and vertically polarized light along a beam path, and into a smoke cloud, to generate scattered light. A horizontally polarized detector and a vertically polarized detector are positioned at different locations, but at a same distance and scattering angle relative to the beam path. Each unit has a different wavelength. A computer receives signals from the detectors of all units, in response to each emitter, for analysis of the smoke.

Abstract: An optical device for establishing a spatial orientation for a drill bit includes at least three light sources and two cameras. The first light source is used to silhouette the drill bit; a second light source is used to generate a reflection from a primary facet of the drill bit; and a third light source is used to generate a reflection from the margin of the drill bit. In sequence, the first camera responds to the first light source to establish an axial position for the drill bit on the axis. The second camera then responds to the second light source to establish a gross rotational position for the drill bit on its axis. Finally, the first camera is again used. This time it establishes a precise rotational position for the drill bit on its axis to establish the spatial orientation for the drill bit.

Abstract: An optical fiber security system includes an optical emitter connected to one end of an optical fiber and a detector connected to the other end. A random signal generator triggers the emitter to output a light pulse signal through the fiber. This generator also simultaneously triggers the detector to receive the light pulse signal. A comparator compares the light pulse signal that is received by the detector with an optimum reference to adjust and conform the emitter output with the reference. Also, a monitor determines whether a particular identifiable characteristic of the light pulse signal is within a predetermined range of values. Whenever there is not a simultaneous emission and detection of the light pulse signal, or whenever the light pulse characteristic is outside the predetermined range of values, the system alarms.