Abstract: An optical short pulse generating device is disclosed, in which semiconductor laser light of a fixed intensity is launched into a first semiconductor electroabsorption optical modulator which is driven by a 0V or forward bias voltage and a sinusoidal voltage, and the output light from the first optical modulator is launched into a second electroabsorption optical modulator to which is applied a bias voltage and a sinusoidal voltage having delayed from the said sinusoidal voltage for a period of time corresponding to the phase reversal thereof, whereby it is possible to generate optical short pulses of a repetition frequency twice higher than the oscillation frequency of a sinusoidal voltage generator.

Abstract: This invention aims at providing an oxygen concentration sensor having electrodes which are excellent in heat resistance and durability and maintain quick response. An electrode 26 on an exhaust side is formed on one of the side surfaces of a solid electrolyte 25, and an electrode 24 on an atmosphere side is formed on the other side surface. The electrode 26 on the exhaust side has a composite structure comprising a skeletal electrode 26a and a reaction electrode 26a. The skeletal electrode 26a has a film thickness of 5 to 20 .mu.m and a porosity of less than 10%, and is a heat-resistant thick film for primarily forming a skeletal region. In contrast, the reaction electrode 26b has a film thickness of 0.5 to 2 .mu.m and a porosity of 10 to 50%, and is a high response thin film for primarily forming a reaction region.

Abstract: An air fuel ratio detecting apparatus by which a stable oxygen ion limit current may be obtained, including a working electrode and a gas diffusion resistance layer laminated in this order on a first surface of a solid electrolyte. An ambient air introduction duct and an electric heater are laminated in this order on a second surface of the electrolyte. The gas diffusion resistance layer is composed of a gas permeation layer and gas shield layer, which is provided on a surface of the gas diffusion resistance layer. Since the surface of the gas permeation layer is covered by the gas shield layer, the gas to be measured enters into the gas diffusion resistance layer from only side faces of gas diffusion resistance layer. A cell is preferably baked in a one-piece manner. A porosity of the gas permeation layer is in a preferable range of from about 2 to about 60%, a thickness of the gas permeation layer is preferably in a range of from about 5 to about 300 .mu.

Abstract: An adhesive patch for percutaneous delivery of isosorbide dinitrate includes a piece of separating paper; a percutaneous salve preparation which is solvent free and which is comprised of: (a) isosorbide dinitrate; (b) a percutaneous absorption accelerator which is at least one substance selected from the group consisting of a chained monocarboxylate and a higher alcohol; and (c) a tackifier composition as an additive, wherein the chained monocarboxylate is selected from the group consisting of isopropyl palmitate, isopropyl myristate, cetyl lactate, diethyl sebacate, xylol laurate, cetyl isooctanoate and lauryl lactate, wherein the higher alcohol is selected from the group consisting of cetanol, stearyl alcohol, lauryl alcohol, cetostearyl alcohol and myristyl alcohol, and wherein the percutaneous absorption accelerator is present in an amount ranging between 3 and 12 wt % if a chained monocarboxylate is used and between 1 and 3 wt % if a higher alcohol is used; and a surface coating material which is polymer

Abstract: To perform waveform shaping, retiming and amplification of the transmitted pulse signal of a binary PCM fiber optic communication employing an optical pulse signal which has a pulse duty factor within 1 with respect to a time slot, an optical waveform shaping device is proposed in which the optical pulse signal is branched by an optical branch circuit into two optical signals. The one transmitted optical signal passes through a photodetector, a band-pass filter for extracting the fundamental frequency component of the signal, an amplifier and a delay circuit, so that the signal is converted to a sinusoidal voltage synchronized with the optical pulse signal. The other optical signal passes through a semiconductor electrical absorption type optical modulator which is driven by the sinusoidal voltage and a DC voltage, so that the width of a gate waveform is changed by controlling the amplitude of the sinusoidal voltage and the DC voltage.

Abstract: An oxygen sensor capable of accelerating electrochemical reactions and practically working at a low temperature comprises a solid electrolyte 5, and an outer electrode 31 and an inner electrode 32, provided on the surfaces of the solid electrolyte 5, wherein mixed conductors 11 and 12 capable of adsorbing oxygen molecules and conducting an ionization reaction are provided between the solid electrolyte 5 and the outer electrode 31 and between the solid electrolyte 5 and the inner electrode 32, respectively. The mixed conductors 11 and 12 are porous and have a higher oxygen ion conductivity than that of the solid electrolyte 5 and an electron conductivity substantially equivalent to the oxygen ion conductivity and are made of a fluorite-type oxide or a perovskite-type oxide.

Abstract: The short optical pulse generator is provided with a semiconductor laser which oscillates continuously at a single wavelength, a semiconductor electro-absorption type optical modulator which performs the intensity modulation of the output light from the laser, and a sinusoidal voltage generator and a DC voltage generator for driving the electro-absorption type optical modulator. A DC voltage is applied to the electro-absorption type optical modulator so that the output light from the laser is sufficiently extinguished. By applying a sinusoidal voltage to the optical modulator, short optical pulses are generated.

Abstract: A compound type microscope is provided which can observe the measurement sample of an atomic force microscope (AFM) by means of an optical microscope. This compound type microscope is comprised of an optical microscope having an objective and an observation optical system, a cantilever having a reflecting surface and detecting an atomic force, an irradiating optical system for applying a spotlight to the cantilver, a detector for detecting the displacement of reflected light caused by the displacement of the cantilever, and a sample stage for placing a sample thereon. The arrangement can be designed to accommodate the use of a scanning tunnel type microscope (STM) interchangeably with the AFM so that the sample can be measured by the STM instead of by the AFM. To this end, the probe of the STM can be detachably mountable coaxially with respect to the objective of the optical microscope, whereby the probe of the STM and the cantilever of the AFM can be selectively disposed below the objective.

Abstract: An optical modulator in which waveguide regions are disposed at opposite ends of a modulation region to reduce the capacitance of the device and prevent pn junctions from exposure to air. On an n-side electrode there are laminated a substrate, an n-type clad layer and an optical modulation waveguide layer. A modulation region lies at the center of the optical modulation waveguide layer along the direction of travel of light, and two waveguide regions are disposed at opposite ends of the modulation region, respectively. On the optical modulation waveguide layer which constitutes the modulation region there are laminated a non-doped layer, a p-type clad layer and a p-side electrode, and a semi-insulating semiconductor is formed on the optical modulation waveguide layer which forms the two waveguide regions.

Abstract: A four-stroke cycle internal-combustion engine having two large- and small-diameter intake valves and two large- and small-diameter exhaust valves in one cylinder and mounted with a valve-operating mechanism on either of the intake valve side and the exhaust valve side. Each valve-operating mechanism comprises a first valve-operating cam of a narrow total valve-opening angle and a low lift, a second valve-operating cam of a wide total valve-opening angle and a high lift, a rocker arm for the small-diameter valve in direct engagement with the first valve-operating cam, a rocker arm for the large-diameter valve, and a connecting means capable of simultaneously operatively connecting the second valve-operating cam with the rocker arm for the small-diameter valve and the rocker arm for the large-diameter valve. In each cylinder at least three spark plugs are mounted. The combustion chamber is formed high on one side and low on the other side.

Abstract: An optical semiconductor device manufacturing method is disclosed which involves an ion implantation step of implanting ions into a compound semiconductor wafer through an ion implantation mask and an annealing step of activating atoms in the compound semiconductor wafer through an annealing mask film. The ion implantation step and the annealing step are performed in succession after laminating mono- or multi-layered compound semiconductor layers as the ion implantation mask and the annealing mask film on the compound semiconductor wafer.

Abstract: An optical modulating device is disclosed which has, on a substrate directly or via a lower cladding layer, an optical waveguide layer, an upper cladding layer of a refractive index smaller than that of the optical waveguide layer and a pair of electrodes for applying an electric field across the substrate and the upper cladding layer and in which the absorption coefficient for incident light of a fixed intensity incident to the optical waveguide layer is varied by the electric field applied across the pair of electrodes to perform the modulation of the light and the modulated light is emitted from a light emitting end face of the optical waveguide layer. In accordance with the present invention, a pn junction is formed in the upper cladding layer and at least one buffer layer of an energy gap smaller than that of the upper cladding layer but larger than that of the optical waveguide layer is interposed between the upper cladding layer and the optical waveguide layer.

Abstract: An optical modulation element is disclosed which has, on a substrate directly or through a lower clad layer, an optical waveguide layer of a low impurity concentration, an upper clad layer of a refractive index smaller than that of the optical waveguide layer, and electrodes, and in which light of a constant intensity incident on a light incident end face of the optical waveguide layer is intensity-modulated by changing the absorption coefficient of the optical waveguide layer by means of an electric field applied thereto across the electrodes so that the thus modulated light is emitted from a light emitting end face of the optical waveguide layer.

Abstract: An optical modulation device is disclosed in which a difference between the photon energy of incident light and the band-gap energy of the modulation waveguide layer is set to a value greater than 50 meV to thereby suppress the degradation of the modulation voltage and the modulation band width which is caused by an increase in the intensity of incident light and in that the optical modulation device is formed in a predetermined length to thereby decrease the modulation voltage.

Abstract: A lubricant applicator has a horizontally oriented spindle on which a disk to be processed is detachably attached and rotated with the spindle. After a lubricant is sprayed on both its surfaces from nozzles disposed adjacent thereto, the disk is brought between a pair of vertically stretched tapes while rotating with the spindle. A pair of grippers sandwiching the disk applies pressure on its surfaces through the tapes to uniformly control the lubricant film thickness on the disk surfaces.

Abstract: A semiconductor external modulator is disclosed in which the mode of polarization of incident light, the crystal plane of the substrate (the direction of application of an electrical field), the energy gap of the optical waveguide layer, and the direction of travel of light are determined so that, of variations in the real and imaginary parts of the refractive index of the optical waveguide layer which are caused by the application of the electric field to the semiconductor external optical modulator, the variation in the real part of the refractive index may be reduced to substantially zero.

Abstract: A method for manufacturing a semiconductor optical integrated device in which a semiconductor element A having an optical waveguide region and a semiconductor element B having another optical waveguide region are integrated on a single substrate. In accordance with the present invention, there is provided steps of growing the optical waveguide region of the semiconductor element A and a protective layer therefor are grown on the entire area of the substrate surface, selectively removing them from the substrate surface in the region to be ultimately occupied by the semiconductor element B, and forming in the region the optical waveguide region of the semiconductor element B through crystal growth.

Abstract: A semiconductor integrated light emitting device is disclosed which comprises a light emitting waveguide including a light emitting layer, and an external waveguide directly coupled to the light emitting waveguide. In accordance with the present invention, the light emitting waveguide and the external waveguide are mutually laminated in the vicinity of a region where they are directly coupled together.The intensity of the optical output from the light emitting waveguide is modulated in the external waveguide by the electroabsorption effect.

Abstract: A semiconductor optical modulator is disclosed which is capable of high-speed modulation without the necessity of increasing the modulating voltage. The present invention has its feature in that the carrier density of the clad layer adjoining the optical waveguide layer 3 is gradually raised toward the p-n junction or Schottky junction, thereby increasing the width of the depletion layer to decrease the junction capacitance.

Abstract: A still image pickup camera has a solid state image pickup device comprising an image pickup area, a temporary storage area, and a horizontal shift register. The signal charges in the image pickup area are transferred to the temporary storage area by the transfer pulses which are given for a vertical blanking period. Clear pulses which are equivalent to the transfer pulses are given at a desired timing in the interval between the vertical sync signals so as to enable the photo sensing interval (storage interval) in the image pickup area to be reduced and varied, thereby transferring the signal charges in the image pickup area to the temporary storage area and clearing the image pickup area.