Abstract: A structure printer for printing structures that has a stable platform on which a swiveling base is mounted. A boom is extendible from the base having a plasmatron mounted on the end of the boom for heating and melting the building material, which may subsequently be sprayed by a print head that receives the molten material from the plasmatron, the print head having an adjustable nozzle for expelling the mixture in a specific location. The printer may be vehicle-mounted, and may have a computer control so it is able to print a building faithfully from a blueprint. The building material may be foam glass, or other mixtures may be used.

Abstract: A method and apparatus are operative to control the desired level of population inversion in a gain medium having an amplified spontaneous emission (ASE) spectrum which is characterized by distinct short- and long-wavelength regions. The control is realized by the apparatus configured to determine a relationship between the regions of the ASE spectrum represented by respective frequencies which are filtered by respective frequency discriminators. The apparatus includes a controller operative to process the filtered frequencies by determining a relationship between amplitudes of the respective filtered frequencies which represents a measured level of population inversion. Upon mismatch between the measured level and desired level of the population inversion, a control signal is coupled into a pulse generator or pump or both. In response, the pulse generator may output a pulse, or/and the pump may be completely shut down to lower the level of the measured inversion.

Abstract: A method for contactless laser welding of a plurality of sheets of material stacked upon one another includes simultaneously delivering a laser beam and a stream of fluid through a laser head and further through an end cap which is removably mounted to the laser head. The end cap is configured with a stationary cylinder, which is coupled to the laser head, and a piston movable relative the cylinder. The piston moves in response to a pressure differential generated by the fluid in chambers above and below the piston. Once the pressure equilibrium is reached between the chambers, the pressure in the chamber below the piston is sufficient to reliably press the sheets of material against one another during a laser welding operation.

Abstract: An ultra-long fiber-optic transmission system is configured in accordance with the current telecom standards and particularly advantageous for transmission data at a long distance which may exceed 400 km between adjacent nodes. The disclosed system has at least one intermediate amplifying node provided with a supervisory optical channel (SOC) which carries information between spaced nodes about the multi-wavelength optical signal as well as remote conditions at the optical terminal or regeneration site. The SOC comprises a transponder operative to select the direction in which an optical supervisory signal OSS, carrying information about the fiber break and malfunction of WDM channels, is transmitted along the SOC. The transponder further includes a receiver operative to measure the power of incoming OSS signal, which is indicative of the power of the transmitted and amplified WDM signal, and a Raman controller.

Abstract: A method and laser system for dynamically adjusting a transient wavelength of light pulses emitted by a laser includes sequential processing of transient photocurrent curves which are generated after interaction between each light pulse and wavelength-selective medium which is configured with a known spectral peak line selected in the range of the transient wavelength. The method further includes continuously processing parameters of sequentially generated curves until the processed parameters are repeatedly uniform.

Abstract: An ultra-long fiber-optic transmission system is configured in accordance with the current telecom standards and particularly advantageous for transmission data at a long distance which may exceed 400 km between adjacent nodes. The disclosed system has at least one intermediary amplifying node provided with a supervisory optical channel (SOC) which comprises a transponder operative to select the direction in which a supervisory channel signal (SCS), carrying information about the fiber break and malfunction of WDM channels, is transmitted along the SOC. The transponder further includes a receiver operative to measure the power of incoming and a Raman controller coupled to the receiver and to either turn or turn off a pump of Raman amplifier based on determination of whether the measured power of the SCS is lower than or at least equal to a reference value. The transponder is further configured with a transmitter configured as a fiber laser which operates in at least two modes.