Abstract: A method of obtaining a set of measurements for making a position determination. Laser ranging measurements are made from at least two spaced apart stations with respect to a common distant moving object. The ranging measurements utilise respective signals transmitted from the stations so as to impact the moving object at substantially the same time. By making ranging measurements for a plurality of positions of the moving object the position determination can be made by triangulation techniques.

Abstract: A method of obtaining a set of measurements for making a position determination. Laser ranging measurements are made from at least two spaced apart stations with respect to a common distant moving object. The ranging measurements utilise respective signals transmitted from the stations so as to impact the moving object at substantially the same time. By making ranging measurements for a plurality of positions of the moving object the position determination can be made by triangulation techniques.

Abstract: A method of obtaining a set of measurements for making a position determination. Laser ranging measurements are made from at least two spaced apart stations with respect to a common distant moving object. The ranging measurements utilise respective signals transmitted from the stations so as to impact the moving object at substantially the same time. By making ranging measurements for a plurality of positions of the moving object the position determination can be made by triangulation techniques.

Abstract: A method and apparatus for transmitting and receiving optical signals in a bi-directional transmission system (1) using a common transmission medium (3). Laser radiation at the first wave length and intensity is directed from a laser source (4) to a non-linear optical device (6). The non-linear optical device (6) is responsive to radiation at the first wavelength and intensity is directed from a laser source (4) to non-linear optical device (6). The non-linear optical device (6) is responsive to radiation at the first wavelength and intensity to emit radiation of a second wavelength which is transmitted through the medium (3). The non-linear optical device (6) transmits incident radiation of the second wavelength have less than a selected intensity.

Abstract: An apparatus and method for transmitting a hazardous electromagnetic beam (10). A hazardous beam (10) and a non-hazardous beam (12) are generated and directed along respective paths which are substantially parallel and either at least partially coincident or in close proximity so that an object will traverse the path of the non-hazardous beam (12) immediately before it is impinged by the hazardous beam (10). Any disturbance of the non-hazardous beam (12) by an object is detected and the hazardous beam (10) is disabled in response to a predetermined disturbance.

Abstract: A solid state laser beam generating system includes a solid state laser which produces a laser beam having a wavelength outside the eyesafe range of 1.5 .mu.m to 1.8 .mu.m. A converter including a non-linear structure is used to convert the laser beam to a beam having a wavelength within the eyesafe range. The non-linear structure has three defined principal axes and the input laser beam to the structure travels in a direction offset from one of the principal axes by an angle greater than 2.degree..

Abstract: A laser cavity assembly includes means (12, 13, 14; 14", 56, 57) defining respective optical resonance cavities (20, 22) for stimulated radiation of different wavelengths, which cavities include at least some common volume. Such means includes window means (13, 14) for emission of radiation amplified in the respective cavities. Means (15, 54) in one of said cavities is responsive to stimulated radiation emitted by a laser medium at one of the wavelengths to emit radiation at another of the wavelengths. Dual mode means (12, 54) has respective selectable first and second modes at which the laser cavity assembly is adapted to emit laser radiation predominantly at the respective wavelengths. Also disclosed are a novel Q-switch device and a combination laser oscillator and dual mode means.

Abstract: A laser assembly includes a lasing medium (12), associated reflector components (14, 16) defining a resonance cavity, and means (16) for outputting laser pulses therefrom. Means (18) is provided to pump the lasing medium with pulses of predetermined energy. There is a pumping circuit (20) for activating the pump means, and control means (22, 34, 35) associated with said pumping circuit for determining the energy of the pumping pulses.