Abstract: A semiconductor light emitting device includes a multi-layered semiconductor layer having at least a first conductive type cladding layer, an active layer, a second conductive type first cladding layer, an etching stop layer, and a second conductive type second cladding layer on a substrate. An upper section of a ridge groove is formed by an anisotropic etching process, as a first groove in such a way as to have a depth from a surface of the multi-layered semiconductor layer and as not to cross the etching stop layer at the depth. A bottom groove of the ridge groove is formed by an isotropic etching process, as a second groove by performing etching in such a way as to be stopped by the etching stop layer.

Abstract: An edge-emitting semiconductor laser includes a resonator structure having an active layer. A low reflection three-layer film is provided on in emitting edge face of the resonator structure and a high reflection multi-layer film is provided on a rear edge face of the resonator structure. The low reflection three-layer film is formed in an exemplary embodiment by sequentially stacking a first Al2O3 layer having a thickness of 10 nm, an Si3N4 film having a thickness of 190 nm, and a second Al2O3 layer having a thickness of 10 nm.

Abstract: A semiconductor light emitting device includes a multi-layered semiconductor layer having at least a first conductive type cladding layer, an active layer, a second conductive type first cladding layer, an etching stop layer, and a second conductive type second cladding layer on a substrate. An upper section of a ridge groove is formed by an anisotropic etching process, as a first groove in such a way as to have a depth from a surface of the multi-layered semiconductor layer and as not to cross the etching stop layer at the depth. A bottom groove of the ridge groove is formed by an isotropic etching process, as a second groove by performing etching in such a way as to be stopped by the etching stop layer.

Abstract: A method of manufacturing a ridge type semiconductor light emitting device includes: a process of epitaxially growing a multi-layered semiconductor layer having at least a first conductive type cladding layer, an active layer, a second conductive type first cladding layer, an etching stop layer, and a second conductive type second cladding layer on a substrate; a process of forming a ridge groove for forming a ridge; and a process of forming a current-flow barrier layer in the ridge groove. The process of forming ridge grooves has first and second anisotropic etching processes of performing anisotropic etching, an etching-mask forming process, and an isotropic etching process of performing anisotropic etching.

Abstract: An edge-emitting type 650 nm band red semiconductor laser device is provided, which includes a resonator structure having an active layer on a semiconductor substrate. A low reflection three-layer film is provided on an emitting edge face of the resonator structure and a high reflection multi-layer film is provided on a rear edge face of the resonator structure. The low reflection three-layer film is formed by sequentially stacking a first Al2O3 film having a thickness of 10 nm, an Si3N4 film having a thickness of 190 nm, and a second Al2O3 film having a thickness of 10 nm on the emitting edge face by a sputtering process. The edge reflectance at the emitting edge face is set to 10%. The high reflection multi-layer film is formed by alternatively stacking Al2O3 films and a-Si films on the rear edge face.

Abstract: An edge-emitting type 650 nm band red semiconductor laser device is provided, which includes a resonator structure having an active layer on a semiconductor substrate. A low reflection three-layer film is provided on an emitting edge face of the resonator structure and a high reflection multi-layer film is provided on a rear edge face of the resonator structure. The low reflection three-layer film is formed by sequentially stacking a first Al203 film having a thickness of 10 nm, a SiN4 film having a thickness of 190 nm, and a second Al203 film having a thickness of 10 nm on the emitting edge face by a sputtering process.

Abstract: A method of manufacturing a ridge type semiconductor light emitting device includes: a process of epitaxially growing a multi-layered semiconductor layer having at least a first conductive type cladding layer, an active layer, a second conductive type first cladding layer, an etching stop layer, and a second conductive type second cladding layer on a substrate; a process of forming a ridge groove for forming a ridge; and a process of forming a current-flow barrier layer in the ridge groove. The process of forming ridge grooves has first and second anisotropic etching processes of performing anisotropic etching, an etching-mask forming process, and an isotropic etching process of performing anisotropic etching.

Abstract: An edge-emitting type 650 nm band red semiconductor laser device is provided, which includes a resonator structure having an active layer on a semiconductor substrate. A low reflection three-layer film is provided on an emitting edge face of the resonator structure and a high reflection multi-layer film is provided on a rear edge face of the resonator structure. The low reflection three-layer film is formed by sequentially stacking a first Al2O3 film having a thickness of 10 nm, an Si3N4 film having a thickness of 190 nm, and a second Al2O3 film having a thickness of 10 nm on the emitting edge face by a sputtering process. The edge reflectance at the emitting edge face is set to 10%. The high reflection multi-layer film is formed by alternatively stacking Al2O3 films and a-Si films on the rear edge face.

Abstract: A galvanic cell type gas sensor which utilizes the respective merits of galvanic cell type and polaro type gas sensors so that a plurality of gasses can be detected by one sensor. One working electrode is utilized in conjunction with two or more counter electrodes which are different in kind from each other. Each of the electrodes are individually selected corresponding to a type of gas to be detected. Also, drift in the measurement of one of the detected gasses can be corrected based upon the measurement of another of the detected gasses.

Abstract: A sensor for measuring concentrate of solute in an aqueous solution in which a humidity sensor is enclosed and sealed within a porous fluorine polymer film that is liquid water impermeable but water vapor permeable. The sensor operates by measuring water vapor pressure in the gaseous phase inside the sealed film after the inside and outside have equilibrated with respect to water outside and inside.

Abstract: A method and process for processing picture image signals detects color separation signals of a color original image and then respectively converts these color separation signals into digital color separation signals. These digital color separation signals are then multiplied by predetermined coefficients and the results of these multiplications are sequentially accumulated for equalizing the levels of the digital color separation signals at a grey point of the original image so as to thereby obtain digital color separation signals which are converted to equivalent neutral densities. Hue signals of yellow, green, cyan, blue, magenta, and red which divide a color space into six hues are obtained from the digital color separation signals which are converted to the equivalent neutral densities. The hue signals are multiplied by predetermined color correction coefficients and the results thereof accumulated for color correction signals on yellow, magenta, and cyan.

Abstract: A picture image input/output system which can obviate defects encountered in prior art systems is arranged such that plural original color pictures are enlarged or reduced at a predetermined magnification ratio respectively by a picture image scanning device and color separated to obtain color separation signals; such color separation signals are processed for appropriate color correction, sharpness enhancement and gradation conversion, and lay-out picture images are sequentially outputted on a recording material using lay-out instructions and information.

Abstract: In the invention, an electrochemical cell including an oxygen reducing cathode, an oxygen generating anode and an electrolyte, and having both a deoxygenating function and an oxygen generating function is coupled to a chamber in such a manner that, when the oxygen concentration in the chamber is much higher than a predetermined value, the deoxygenating function is utilized to decrease the oxygen concentration and when the oxygen concentration in the chamber is much lower than the predetermined value, the oxygen generating function is utilized to increase the oxygen concentration so that the oxygen concentration in the chamber is maintained at the predetermined value.

Abstract: A galvanic cell type oxygen sensor comprising a galvanic cell comprised of a cathode made up of metal effective for the electrolytic reduction of oxygen, an anode made up of lead material and an electrolyte made up of an aqueous mixed solution of organic acid and organic acid salt, which has a long life and a high output voltage, is not at all affected by carbon dioxide and which can prevent the generation of hydrogen from the cathode, is disclosed.

Abstract: A device for inspecting the surface of an article such as a moving paper web by scanning a bent surface of the object tangentially with a laser light beam. The scanned beam is received and converted into an electrical signal in which peaks therein above a pre-set level represent defects in the object. A servo feedback circuit is disclosed for maintaining the position of the scanning beam constant with respect to the inspected surface of the object despite variations in the position of the mechanism conveying the object.

Abstract: A method of storing foodstuffs and an apparatus for practicing the same, in which an electrolytic cell includes a gas diffusion cathode capable of reducing oxygen electrolytically and an oxygen liberating anode, and a DC voltage is applied to the electrolytic cell while the gas in a food storage chamber is brought into contact with the cathode to remove oxygen from the storage chamber, whereby the oxygen concentration in the storage chamber is controlled to a desired value.