Abstract: A lateral transistor having a high breakdown voltage and operable with an improved current amplification factor and an improved cut-off frequency comprises in a semiconductor substrate of one conductivity type, a base layer of the one conductivity type and an emitter layer of the other conductivity type formed in the base layer. A first collector layer of the other conductivity type is formed in the one principal surface of the substrate apart from the base layer and a second collector layer of the same conductivity type having an impurity concentration lower than that of the first collector layer is formed between the first collector layer and the base layer in contact with the latter layers. Emitter, base and collector electrodes make ohmic contact with the emitter, base and first collector layers respectively. The emitter electrode extends on a passivation film covering the one principal surface of the substrate to terminate at a point on the second collector layer.

Abstract: A process and apparatus for producing an optical fiber preform by oxidizing a gaseous glass forming material with a flame from a burner and depositing the resulting soot in a rod form are described, wherein two signal beams, supplied by splitting a light beam, are projected in a direction normal to the direction in which the preform grows and are directed into the space between the burner and the deposition face of the preform, and they are positioned so that one beam partially contacts the deposition face of the preform, while the other beam is directed to pass between the burner and the deposition face, and the distance between the burner and the deposition face is controlled such that the ratio of the intensity of the two beams passing through the space between the burner and the deposition face is held constant.

Abstract: The buffer circuit is provided with a high sensitivity balanced type flip-flop circuit and a capacative coupling provided by MOS capacitance, and a load drive circuit utilizes bootstrap effect, thus producing complementary signals having a MOS level from a TTL address input signal.

Abstract: The analog output from a local DAC comprising an LDAC and an MDAC, in which the full scale of the LDAC is always larger than the quantized level of the MDAC, is compared with an input analog signal which is sampled and held. A digital code obtained by successive approximation in accordance with the result of the comparison is stored in a successive approximation register. A shift code for calibrating the D/A conversion in the local DAC by shifting the digital code which is previously allotted to each digital code is stored in a shift code generating circuit (ROM). The digital code from the successive approximation register is digitally shifted in accordance with the shift code by a code shift circuit such as a digital adder/subtractor to obtain an A/D conversion output. An analog to digital converter with a high accuracy and an improved conversion speed is inexpensively fabricated in the form of a one chip LSI by a usual CMOS process.

Abstract: Manufacturing method of doped silica glass suitable for optical fiber wherein quartz powder or SiO.sub.2 glass fine particles are exposed to a gas for producing the doped silica glass containing SiCl.sub.4, a gaseous additive and water vapor (H.sub.2 O) to add the dopant to the glass body, and then the resulting glass body is fused at a high temperature, thereby producing a transparent doped silica glass in which the production of the glass particles, the addition of the dopant, and the vitrification of the glass body are carried out by separate steps under respective suitable conditions. The manufacturing speed is remarkably increased because of the separate steps. The content of the dopant is not limited, but can be adjusted with any desired amount by changing the reaction time of dissolution. Dopant components like PbO.sub.2, SnO.sub.2, ZnO which were typically not added to the glass body can now be added thereto.

Abstract: A process for producing a porous optical fiber preform by hydrolyzing a gaseous glass forming material with a flame from an oxyhydrogen burner and depositing the resulting soot in a rod form in a muffle furnace is described, wherein the muffle furnace is supplied with a gas other than that from the oxyhydrogen burner, and said gas is maintained at a constant temperature.

Abstract: A base region and a collector region of a bipolar transistor are interconnected through a hetero junction and forbidden band gap of the collector region is larger than that of the base region. When the transistor is made of a silicon base material, the collector region is made of oxygen containing polycrystalline silicon or amorphous silicon, whereas when made of a GaAs base alloy, the collector region is made of a mixed crystal of GaAs-AlAs.

Abstract: A tuning fork type vibrator for an optical chopper in a photosensor, which vibrator oscillates at a single frequency. The vibrator comprises vibrating plates so disposed as to face each other with a predetermined spacing therebetween, and a stem portion obtained by bonding together bent portions located at one end of each of said vibrating plates.

Abstract: There is disclosed a method of fabrication of a Josephson tunnel junction device. A surface of a base electrode of Nb or Nb compound is subjected to sputter cleaning and then to plasma oxidation in an atmosphere of a diluent gas and oxygen to form thereon an oxide layer serving as a tunnel barrier. A counter electrode is then formed on the oxide layer to provide the Josephson tunnel junction.

Abstract: A digital to analog converter comprising a first digital to analog converter for generating an output signal of higher order bits; a second digital to analog converter for generating a full scale output as an output signal of lower order bits which is always larger than the output value (1 LSB) corresponding to one bit of a digital input at the least significant bit of the first digital to analog converter; adding means for adding the output signal from the first digital to analog converter to the output signal from the second digital to analog converter to form an analog output signal; and a code converter for applying to the first and second digital to analog converters an input code obtained by shifting a digital input signal applied to the first and second digital to analog converters by a given value such that the relationship between the digital input signal and the analog output signal is made substantially linear.

Abstract: Spaced recesses are formed in a surface of a low impurity concentration P type single-crystal substrate by using a mask. A P type impurity is diffused at a high concentration into an entire surface of the substrate including the recesses to form a P type diffused layer, and an N type layer is epitaxially grown on the P type diffused layer. Then, mask layers are formed on bottom surfaces of the recesses in the epitaxially grown N type layer and this N type layer is anisotropically etched by using the mask layers to form island regions in the recesses. After removing the mask layers, N type diffused layers are formed to cover the island regions. An insulating film (SiO.sub.2) acting to isolate completed transistor elements is formed on the P and N type diffused layers, and a polycrystalline silicon layer acting as a support of a dielectrically isolated integrated circuit device is formed on the insulating film.

Abstract: A gray scale facsimile signal is divided into a plurality of block signals, each composed of a plurality of picture element signals. For each block signal are obtained binary space information indicating whether the level of each picture element signal is higher or lower than a threshold value, mean gradation information of the picture element signals having the levels above the threshold value and mean gradation information of the picture element signals having levels below the threshold value. When the difference between the two pieces of mean gradation information representing the gradation of the block signal is smaller than a predetermined value and/or when the number of picture element signals of the levels either higher or lower the threshold value is smaller than a predetermined value, the block signal is represented by one of the two pieces of gradation information and the entire space information of the block signal is set to one value of the binary space information.

Abstract: A core torch for fabricating a single-mode optical fiber preform wherein fine glass particles are produced eccentrically with respect to the center area of a flame stream, the core torch being so arranged as to blow the flame stream at an angle inclined to a seed rod. The porous glass body forming the core is grown on one end of the rod and in the direction of the axis of the rod. A cladding layer is formed on the periphery of the porous glass core body by at least one torch for forming the cladding. The obtained porous glass body is heated and vitrified into a transparent glass body, which is sealed in a silica tube for jacketting to form a single-mode optical fiber preform. At least one exhaust port is disposed within a distance of 1 mm to 50 mm from the periphery of the porous glass body and in the vicinity of the growing surface of the glass body to exhaust residual glass fine particles and undesired gases. A porous glass body having a diameter of 20 mm or less is easily formed.

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: In a diffraction grating made of a single crystalline silicon substrate, one major plane thereof is provided with a plurality of asymmetric triangular grooves, each having a wall inclined by an angle .theta. with respect to the major surface so as to satisfy an equation.theta.=sin.sup.-1 m.lambda..sub.B /2Pwhere .theta. represents the blaze angle, P the pitch of the groove, .lambda..sub.B the blazing wavelength, and m the order of diffraction. The walls of each groove receiving incident light is covered with a metal coat.The diffraction grating is prepared by using a {hkl} plane (where h=k) inclined by .theta. with respect to the {111} plane of the single crystalline silicon as a major surface, and then anisotropic-etching the major surface through an etching mask having stripes having sufficiently smaller width than the grating constant. Preferably, following the anisotropic etching, isotropic etching is made for the major surface.

Abstract: A process for producing a glass perform for optical transmission fibers, which includes supplying a gaseous silicon compound, ammonia or a gaseous nitrogen compound, and an oxygen-containing gas as starting gases into a high temperature zone to produce fine particles of SiOxNy glass and depositing the fine particles in the form of a soot or a transparent glass on a starting member to produce nitrogen-doped silica glass.

Abstract: A plasma deposition apparatus having a plasma formation chamber and a specimen chamber which are arranged separately. Gaseous material and microwave power are introduced to the plasma formation chamber to generate plasma by a microwave discharge through electron cyclotron resonance. The plasma is extracted to the specimen chamber from the plasma extracting orifice. In the specimen chamber, the plasma is accelerated by the effect of divergent magnetic field to irradiate the surface of the specimen so as to deposit a thin film on the specimen substrate. A high-quality thin film is formed with a high efficiency at a low temperature. Accordingly, a thin film can be deposited on a specimen substrate having a low heat resistivity. The plasma deposition apparatus is useful for manufacturing various kinds of electronic devices.

Abstract: An electron lens system wherein at least two coils are arranged in the vicinity of an electron-optical lens and are excited in directions opposite to each other, thereby making it possible to adjust the focal distance of the lens without including a rotation attributed to the electron-optical lens in an electron beam which passes through the lens.

Abstract: Disclosed is a semiconductor integrated circuit device comprising a semiconductor chip including a plurality of elements constituting multi-functional circuits and a control signal generating circuit incorporated within the semiconductor chip. The control signal generating circuit includes a variable resistance element which irreversibly changes its resistivity when a voltage having a magnitude larger than a specific level, is applied. The variable resistance element is connected in series with a fixed resistor which is further connected in parallel to the output electrodes of a field effect transistor. A control signal is applied to the input terminal of the transistor when the resistance of the variable resistance element is intended to change. An output terminal connected to the connection of the serial connected elements indicates logical "1" or "0" depending on whether the variable resistance element is in the high resistivity state or low resistivity state.

Abstract: Coated optical glass fibers are described, wherein the coating composition comprises an unsaturated polyester containing at least one of (1) polyethylene glycol or polypropylene glycol having an average molecular weight of from 200 to 1,000 as a glycol component, (2) a long chain saturated aliphatic dibasic acid containing 12 or more carbon atoms as saturated polybasic acid component, and an acrylate or methacrylate, and (3) a long chain saturated aliphatic dibasic acid containing 6 or more carbon atoms as a saturated polybasic acid component and a long chain aliphatic dihydric alcohol containing 4 or more carbon atoms as a glycol component; and an acrylate or methacrylate.