Abstract: In a flash device arranged to determine the aperture value of a photo-taking lens according to the measured level of a reflection light obtained by preliminary flashing and to control main flashing according to a light control level corresponding to the aperture value, when a light diffusing panel is arranged in front of a main flashing part for a wider flash illuminating angle, another light diffusing panel which gives an equal light reducing effect is also arranged for a preliminary flashing part. The light quantity of preliminary flashing is thus reduced in proportion to the degree of reduction in the light quantity of main flashing, so that the aperture value set by preliminary flashing and the light controllable range of main flashing for photographing can be made to be always in agreement with each other.

Abstract: A method and apparatus for coating optical transmission glass fibers with a resinous composition. A vessel is provided through which a glass fiber is drawn. While it is being drawn through the vessel, the fiber is spun, and a resin coating is applied. In order to maintain the air pressure within the vessel fairly constant, an exhaust vent is provided through which excess particles of the resinous composition may escape. Turbulence is thus substantially reduced preventing the fiber from swinging and allowing the particles to be sprayed smoothly. Further, the particles may be electrically charged so that they are both attracted to the optical fiber and repel one another during flight. The invention employs both of these features to produce a uniform coat on an optical transmission glass fiber.

Abstract: A method and apparatus for coating optical transmission glass fibers with a resinous composition. A vessel is provided through which a glass fiber is drawn. While it is being drawn through the vessel, the fiber is spun, and a resin coating is applied. In order to maintain the air pressure within the vessel fairly constant, an exhaust vent is provided through which excess particles of the resinous composition may escape. Turbulence is thus substantially reduced preventing the fiber from swinging and allowing the particles to be sprayed smoothly. Further, the particles may be electrically charged so that they are both attracted to the optical fiber and repel one another during flight. The invention employs both of these features to produce a uniform coat on an optical transmission glass fiber.

Abstract: In the disclosed flash device, a flash portion is shiftable from an ordinary flash position to a bounce flash position. Automatically controlling the illuminating angle of the flash portion on the basis of the focal length of the lens of the camera can degrade the effect of the flash photography. This is obviated by controlling the illuminating angle for bounce flash independent of the information on the focal length of the lens.

Abstract: An electronic flash device including a main light part, a pre-emission light part, an illumination direction changing mechanism for changing the illumination directions of the main light part and the pre-emission light at the same time in the case of bounced light photography, and a control mechanism for deciding the aperture value of the photographing lens in accordance with the light measuring level of the reflected pre-emission light and controlling the main light part with the light adjusting level corresponding to the aperture value.

Abstract: A process for producing high-purity silica glass wherein glass-forming chlorides, hydrogen gas, oxygen and an inert gas are supplied from a glass burner, the chlorides are decomposed by flame oxidation to form fine grains of glass which are deposited on a starting member and the glass deposit is sintered to provide a transparent vitreous substance, the volume ratio of oxygen gas to the sum of the chlorides and hydrogen gas being greater than about 0.6, preferably greater than about 1.0, and less than about 20.

Abstract: A glass fiber for use in optical transmission which comprises a first layer containing an organopolysiloxane having a refractive index higher than that of the glass which forms the outermost layer of the glass fiber, a second layer comprising an organopolysiloxane which is the same or different than the organopolysiloxane in the first layer, and a thermoplastic resin coated on the second layer in a thickness less than about 100 microns.

Abstract: In a glass fiber for optical transmission comprising a primary coat, a thermoplastic resin coat, and a buffer coat between the primary coat and the thermoplastic resin coat, the improvement which comprises said thermoplastic resin being a polyamide having a modulus of elasticity of about 2,000 to 8,000 kg/cm.sup.2 at a temperature in the range of 20 to 23.degree. C.

Abstract: An apparatus for treatment of rubber and plastic wastes, comprising in series an extruder for heating and melting rubber and plastic wastes to extrude the molten wastes, a decomposing section for heating the molten wastes to prepare decomposed products while optionally separating residues therefrom, a dry-distilling section for gasifying the decomposed products by dry-distillation, and a cooling section for cooling the dry-distilled products to separate gaseous materials from liquid materials.

Abstract: A method for the treatment of rubber and plastic wastes, comprising in series the steps of1. heating and melting rubber and plastic wastes at a temperature (T.sub.1) to extrude the molten wastes with one or a plurality of extruders into one or a plurality of decomposing zones,2. heating the molten wastes in the decomposing zone at a higher temperature (T.sub.2) than the heating temperature (T.sub.1) in the extruder to prepare decomposed products while optionally separating residues therefrom,3. introducing the decomposed products into a dry-distilling zone while optionally heating the separated residues in a residue removal zone at an even higher temperature (T.sub.3) than the heating temperature (T.sub.2) in the decomposing zone to remove the residues from the residue removal zone when residues are separated in the decomposing zone,4. heating the decomposed products in the dry-distilling zone at a lower temperature (T.sub.4) than the heating temperature (T.sub.