Abstract: The method for forming a fine pattern on a substrate disclosed includes a step of preparing a hologram having a pattern, a step of irradiating material waves (de Broglie waves) such as neutral beams, ion beams and electron beams on the hologram, and a step of imaging the pattern on the substrate with the material waves being interfered by passing through the hologram. The light source has a source that emits a beam having a coherent wave front. Since the fine patterns are formed by utilizing the interference of material waves, the minimum processing precision can be enhanced to the extent of the wavelength of the material wave.

Abstract: In growing a single crystal of .beta.-BaB.sub.2 O.sub.4 from a melt of BaB.sub.2 O.sub.4 by the Czochralski method, crushed single crystal particles of either .beta.-BaB.sub.2 O.sub.4 or .alpha.-BaB.sub.2 O.sub.4 are used as the starting material of the melt. The primary advantage of using the crushed single crystal particles resides in that transformation of a polycrystal initially nucleated on a platinum rod, which is brought into contact with the melt in place of a seed crystal, to single crystal can be accomplished in a greatly shortened time. In consequnce, high quality single crystals are obtained at good yield.

Abstract: An Er:YVO.sub.4 laser oscillator has an excitation light source constituted by a laser diode and a medium constituted by an Er:YVO.sub.4 crystal in which Er.sup.3+ ions are activators and YVO.sub.4 is a host material. The oscillation light is perpendicular or parallel to c-axis of the crystal. The laser operates in target wavelengths on energy transitions of the Er.sup.3+ ions, the target wavelengths being 510 nm to 590 nm, 840 nm to 870 nm, 970 nm to 1020 nm, and 1450 nm to 1700 nm. The crystal is coated with a TiO.sub.2 --SiO.sub.2 system high reflection mirror coating and a fluoride megnesium-zeolite system antireflection coating corresponding to the target wavelengths and a fluoride megnesium-zeolite system antireflection coating corresponding to the wavelength of the laser diode. These coatings together with an output mirror constitute a resonator. For manufacturing the crystal, Er.sub.2 O.sub.3, Y.sub.2 O.sub.3, and V.sub.2 O.sub.