[en] The principle of the Schlieren method applied to the ultrasonic wave range is presented: diffraction of light by ultrasonic waves; diffraction pattern; image. The advantages of the Schlieren method and the possible applications in nondestructive testing are discussed

[en] A schlieren set-up illuminated with a home made ruby laser, which was conceived in order to study the laser beam-plasma-target interaction in an ambient gas in front of a solid target, is reported. (author)

No abstract available

[en] An experimental investigation was made into the formation and propagation of cylindrical collapsing shock waves in a pulsed induction gas discharge. The shock fronts were made visible and their propagation velocity measured by means of the schlieren method in conjunction with high-speed cine photography in the photoscanning regime and frame-by-frame detection, which made it possible, using the experimental data, to analyze the formation and propagation of the shock waves. A physical picture of the individual stages in the development of the discharge is given on the basis of the experimental results

[en] A m=1, helically displaced current channel was identified in the ASDEX plasma interior during m=2 mode activity. This was achieved by means of simultaneous data obtained from a new gradient sensitive schlieren diagnostic and B_P measurements. They clearly show a rotational-transform-dependent coupling mechanism between the driver m=1 current helix and the m=2 perturbation of the bulk current surrounding it. The mechanism is of central importance for the development of the instability and for the theoretical understanding of mode coupling, mode locking and other varieties of mode structures in plasma. (orig.)

[en] A method for the laser probing of an imploding plasma in the S-300 high-current generator (I = 4 MA, Z = 0.15 Ω, and τ = 100 ns) with the use of a YAG : Nd laser is described. The first version of the method enables obtaining three-frame shadow and schlieren photographs of the plasma of the accelerator load with an exposure of 10 ns and an interval between frames of 25 ns. The second version enables the five-frame probing of the plasma with an exposure of 1 ns and an interval between frames of 10 ns. Stimulated Brillouin scattering in carbon tetrachloride is used to compress the probing laser pulse. A series of shadow and schlieren photographs of the plasma of different liners and Z-pinches are obtained. Mechanisms for the image formation are discussed. The magnitude and gradients of the plasma density are estimated

[en] The conventional x-ray imaging for soft tissue often produced some adverse effects because of contrast medium and high-dose radiation. This report outlines the recently developed a very sensitive x-ray imaging method called as refraction contrast method or x-ray Schlieren method, which allows to detect density difference and irregularity in the soft tissue. In the apparatus (SPring-8 BL47XU), a light emitted from undulator was monochromatized by two-crystal x-ray spectroscope and x-ray passed through a sample was caught by imaging detector equipped with a combination of relay lens and CCD. When a glass capillary (outer diameter: 660 μm, inner diameter: 220 μm) was used as a measuring sample, it was confirmed that the image through geometrical refraction was obtained. When x-ray images of a dragonfly wing obtained by the Schlieren method (sample-detector distance: 5 m) and the conventional contact method were compared, it was demonstrated that reticulate structure of the wing was clearly observed by the former method but not at all by the latter one. At present, the study on efficacy of the refraction contrast imaging is under way using rodents. (M.N.)

[en] The initial stage of a nanosecond discharge in gaps with a high electric field at a cathode is studied by laser methods (interferometric, shadow, schlieren methods). The studies are performed in air at atmospheric pressure. Prominence is given to studying the evolution (appearance and growth) of the plasma channels at an anode and to estimating their parameters.

[en] A new, fast time resolved λ = 2 mm schlieren diagnostic provides experimental evidence of an m=1 particle density perturbation in the plasma interior. (orig.)

[en] A novel set of simplifying assumptions makes computer prediction of schlieren sensitivity possible economically. Predictions correlate with experimental and published figures. Other means of improving sensitivity are given. A compact schlieren system giving binocular stereoscopic viewing is described