This paper reviews the work on the dynamic speckle phenomena observed in the light field scattered from living objects. The dynamic speckles produced from living objects are called “bio-speckles” and fluctuate temporally due to various physiological movements to maintain their lives. This fluctuation of bio-speckles is clearly different from that of speckles produced from the movement of usual diffuse objects such as a ground glass. Dynamic properties of biospeckles are briefly discussed on the basis of the power spectra measured and autocorrelation functions of speckle signals. As examples of the interesting applications of bio-speckles, various methods for non-contact measurements of blood flow and other biomedical activites are introduced.

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Resistless microfabrication of metallization of n-type GaAs formed by projection patterned doping using a KrF excimer laser is described. Silane (SiH₄) gas is used as a source material of the ntype dopant of GaAs. Copper thin films with a linewidth as narrow as 2.35 μm are deposited selectively on the doped region by electroplating using an aqueous CuSO₄ solution. By using the selective metallization process, nonalloyed ohmic contacts can be formed with a specific contact resistance of 2.32X10^-5 Ωcm², which is one-thirtieth of that of conventional alloyed contacts.

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The information on the wind velocity distribution in the atmosphere is indispensable for meteorological and environmental studies. For this purpose remote sensing methods such as coherent lidars and wind profilers have been used. These methods, however, require a complex and large set-up of equipment. This paper describes a new method to measure the wind velocity from cloud motion detected with a portable RM-CW lidar and a CCD camera. The RM-CW lidar is used to measure the cloud height. The movement of cloud images recorded with the CCD camera is determined by image processing techniques. A portable RM-CW lidar system with laser diodes has been constructed. New modulation codes are used for this lidar. Under very noisy background conditions such as in daytime, the influence of background noise is reduced by using these new modulation codes, which have shown to be better than the commonly used M-sequence codes.

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Reduction of laser diode noise was examined by using negative electrical feedback. A laser output noise level was reduced by 14dB in the frequency range below 22 MHz, but was increased above 22 MHz. The experimental result was in good agreement with a theory. The noise level in reading out a video disk was reduced by 3dB to the disk noise level without feedback, and the carrier-to-noise ratio was increased by 3dB consequently.

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A spectroscopic study was carried out of the XeC1 eximer laser ablation of Bi-Sr-Ca-Cu-O and Y-Ba-Cu-O high-temperature superconductors. We investigated the emissions of the ablated products from Bi-Sr-Ca-Cu-O and Y-Ba-Cu-O bulk samples irradiated with excimer laser as a function of laser energy density and partial pressures of oxygen and argon, because the emission provide information on the ablated species and on the ablation as a film deposition source. Emission intensities were found to depend strongly on the laser energy density. In the ablation of the Y-Ba-Cu-O bulk sample under both the oxygen and argon atmospheres, we observed the emissions from excited YO molecules, intensities of which were enhanced under the oxygen atmosphere. These results suggest that YO malecules are produced within the target by ablation and are partly created by oxidation of yttrium atoms in the near-surface region of a plasma plume.

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