Abstract: The pipe inspection method and apparatus can be used to implement rapid, tomographic inspection of a pipe set up at a narrow location. The pipe inspection method includes: a first step for scanning the pipe by translating a radiation source and radiation detector arranged opposedly to the pipe; a second step for the radiation detector to detect radiation that the radiation source has emitted, at given scanning distance intervals; a third step for creating a transmission image of the pipe, based on a radiation dose that the radiation detector has detected; and a fourth step for constructing a tomogram or stereoscopic image of the pipe, based on the transmission image. Thus, it is possible to provide the pipe inspection method and apparatus that can be used to implement rapid, tomographic inspection of the pipe set up at a narrow location.

Abstract: The pipe inspection method and apparatus can be used to implement rapid, tomographic inspection of a pipe set up at a narrow location. The pipe inspection method of the present invention includes: a first step for scanning the pipe by translating a radiation source and radiation detector arranged opposedly to the pipe; a second step for the radiation detector to detect radiation that the radiation source has emitted, at given scanning distance intervals; a third step for creating a transmission image of the pipe, based on a radiation dose that the radiation detector has detected; and a fourth step for constructing a tomogram or stereoscopic image of the pipe, based on the transmission image. According to this invention, it is possible to provide the pipe inspection method and apparatus that can be used to implement rapid, tomographic inspection of the pipe set up at a narrow location.

Abstract: Dielectric bodies are arranged in waveguide portions for passing microwave radiation and for holding a plasma generating chamber 25 at a vacuum. The dielectric bodies are arranged to intersect at least an electron cyclotron resonance area of the waveguide portions. A tip end portion of the dielectric bodies at a side of the plasma generating chamber are positioned toward at a side of the plasma generating chamber from an intermediate portion in an axial direction length of a first permanent magnet which is arranged by enclosing an outer periphery of the waveguide portions, and a tip end portion of the dielectric bodies at a side of the plasma generating chamber is substantially consistent with an inner face of the plasma generating chamber.

Abstract: A laser device equipped with a high-voltage pulse generator wherein the pulse generator supplies an electric energy from a dc power source in an on-off form of a supply voltage to a tank circuit through a transformer, with the switching on and off of the supply voltage being effected in synchronism with the resonance period of the tank circuit. The tank circuit stores the supplied electric energy as a resonance condition so that when the electric energy stored in the tank circuit reaches a predetermined value, a saturable reactor connected between the laser device and the tank circuit becomes saturated and the electric energy in the tank circuit is discharged to the laser device.

Abstract: A discharge tube structure of a gas laser generator has end common vessels at its both end sections and an intermediate common vessel at its intermediate section. The end common vessels and intermediate common vessel are connected through the first and second cooling ducts to a centrifugal blower, which is provided at its center the first communicating port communicating with the first cooling duct and at least two second communicating ports communicating with the second cooling ducts opposed to each other with respect to the first communicating port. The simplified second cooling ducts allows the mixture gas to be supplied smoothly to the intermediate common vessel, thereby increasing the laser output.

Abstract: A gas laser device has an anode and a cathode arranged oppositely in a discharge tube. The cathode comprises a plurality of cathode members each having a predetermined discharge effective cathode surface and each being electrically isolated from others. A switching circuit selects the cathode member(s) used for a continuous wave oscillation and the cathode member(s) used for a pulsed oscillation. The total area of the discharge effective cathode surface(s) of the cathode member(s) used for the pulsed oscillation is selected to be smaller than, preferably 1/3 to 1/2 of that of the discharge effective cathode surface(s) of the cathode member(s) used for the continuous wave oscillation.

Abstract: A gas laser has an electrode of improved construction. The electrode, for example a cathode, comprises an inner cathode and at least an outer cathode spaced from the inner cathode and disposed on the side thereof away from to an anode. Each of the cathodes has a central hole from which glow discharge is formed, and the outer cathode further has a plurality of through-holes around the central hole. A gas medium flowing in a discharge tube passes through the central hole of the inner cathode via the central hole and through-holes of the outer cathode. The gas medium forcedly enters the glow discharge from the inner cathode thereby to cause it expand and a part of the gas medium having passed through the through-holes of the outer cathode squeeze the glow discharge from the outer cathode so that the glow discharge can enter the glow discharge from the inner cathode. Therefore, the current density of the glow discharge in the discharge tube is made information.

Abstract: According to the invention, a thin wire 13 is arranged across the laser beam 2, and the change of resistance in the thin wire 13 is measured by a resistance meter 21 while moving the thin wire 13 by a driving mechanism 23, thereby to measure the power of the laser beam or the position of the laser beam. The apparatus can be used for monitoring the power of laser beam or position of the same used in the high-power laser device for processing or the like purpose. According to the invention, it is possible to monitor the power and position of the laser without interrupting the laser beam and without incurring substantial increase of the loss of power of the laser beam.

Abstract: A gas laser oscillation apparatus wherein, in order to prevent a center axis of a reflecting mirror included in a laser resonator from deviating from an optical axis of the laser resonator due to the deformation of a mirror supporting frame caused by a vacuum force applied to a laser tube, the reflecting mirror is fixed to a mirror holding plate, which is attached to the mirror supporting frame with fasteners such as bolts and nuts.

Abstract: A laser beam axis monitoring apparatus which includes a laser oscillator generating a laser beam and a light generator for generating a light for monitoring an axis of the laser. The light from the light generator is split into ring-shaped light and reflected or lead into the laser oscillator. The light in the laser oscillator is reflected by a total reflection mirror and passes out of the oscillator so that the axis of the laser beam and axis of the light coincide with each other.

Abstract: In a coaxial type gas-flow laser device in which a laser beam axis, an electric discharge axis and a gas flow axis are coincident, at least one centrifugal blower is employed for circulating a laser gas. Where two centrifugal blowers are employed, they oppose to each other in an axial direction of discharge tubes.

Abstract: An invention concerning the electrode structure of a gas laser device is disclosed. In the outer peripheral part of a discharge gas circulating hole (32) provided in the central part of an upper gas stream side one (16) of electrodes (14) and (16) disposed at both the ends of a discharge tube (8), a plurality of gas circulating apertures (34) are further provided over the entire periphery. A glow discharge portion in the discharge tube (8) is fined towards the central part of the tube by a gas which passes through the outer-peripheral gas circulating apertures (34). Thus, the laser intensity profile becomes the Gaussian distribution, and the laser generation efficiency is enhanced.

Abstract: A gas laser generating device of the longitudinal gas flow type having at least two glow discharge tubes, each of which has positive and negative electrodes, electric insulating tubes which are inserted between the two glow discharge tubes in order to provide insulation therebetween, and mirrors which are positioned at the ends of the two glow discharge tubes. In the glow discharge tubes, gas is excited to generate gas lasing and this gas lasing is amplified by the reflections of the mirros. Also, there are further provided triggering electrodes near either the negative or positive electrodes of the glow discharge tubes, respectively, which triggering electrodes are connected to the positive electrodes through triggering resistors, respectively.