Abstract: There is disclosed a semiconductor layer which can emit a continuous laser beam in a visible wavelength range. The laser has an n-GaAs substrate. On this substrate, an n-InGaAlP cladding layer, an active layer, and p-InGaAlP cladding layers are sequentially formed, thus forming a double hetero-structure. A mesa-shaped, upper cladding layer is provided, defining a laser beam-guiding channel. A thin p-InGaAlP contact layer and a mesa-shaped, p-GaAs contact layer are formed on the top surface of the upper cladding layer. Two n-type semiconductive, current-blocking layers cover the slanted sides of the upper, mesa-shaped cladding layer and also the contact layer. They are made of the same n-GaAs compound semiconductor material as the substrate.

Abstract: A method of and an apparatus for recording and reading out radiation image information.

Abstract: In a semiconductor laser device, for emitting a laser beam having a wavelength .lambda., an n-type In.sub.0.5 (Ga.sub.1-x Al.sub.x)P first cladding layer is formed on an n-type GaAs substrate. An undoped InGaP active layer is formed on the first cladding layer and a p-type In.sub.0.5 (Ga.sub.1-x Al.sub.x).sub.0.5 P cladding layer is formed on the active layer. A p-type InGaP cap layer is formed on the second cladding layer and an n-type GaAs current restricting layer is formed on the second cladding layer. The aluminum composition ratio x of the cladding layer is 0.7. The active layer has a thickness of 0.06 .mu.m and the cladding layers have the same thickness H of 0.85 .mu.m. The active layer and the cladding layers have refractive indices n.sub.a and n.sub.c which satisfies the following inequalities:0.015.DELTA..sup.1/2 <d/.lambda.<0.028.DELTA..sup.-1/2and.DELTA.=(n.sub.a.sup.2 -n.sub.c.sup.2)/2n.sub.a.sup.

Abstract: An apparatus for recording and reading out radiation image information including a circulatory feed system for feeding stimulable phosphor sheets. Prior to successive recording of images on the stimulable phosphor sheets, any remaining images and dust are erased from the sheets, and the sheets are checked for defects or scratches thereon. Any sheet bearing such a defect is controlled to skip image recording, readout, and erasing steps. The frequency of erasing the remaining image on a stimulable sheet in the erasing step is controlled dependent on the amount of the radiation to which the object is exposed.

Abstract: There is disclosed a semiconductor layer which can emit a continuous laser beam in a visible wavelength range. The laser has an n-GaAs substrate. On this substrate, an n-InGaAlP cladding layer, an active layer, and p-InGaAlP cladding layers are sequentially formed, thus forming a double hetero-structure. A mesa-shaped, upper cladding layer is provided, defining a laser beam-guiding channel. A thin p-InGaAlP contact layer and a mesa-shaped, p-GaAs contact layer are formed on the top surface of the upper cladding layer. Two n-type semiconductive, current-blocking layers cover the slanted sides of the upper, mesa-shaped cladding layer and also the contact layer. They are made of the same n-GaAs compound semiconductor material as the substrate.

Abstract: A device for supplying specified time-dependent DC current to a reactive load. The device comprises: a DC current source; a DC voltage source connected in series to the DC current source; a detector of the current in the load; a current source controller for causing the detected current to be approximately equal to a stipulated variable current; a detector of the output voltage of the current source; and a voltage source controller to cause the detected output voltage of the current source to achieve a predetermined constant voltage.

Abstract: Disclosed herein is a double-heterostructure semiconductor laser which emits a laser beam in a visible light range at ambient temperature. An active layer serving as a light emission layer is sandwiched between first and second cladding layers. The first cladding layer comprises an n type InAlP, while the second cladding layer comprises a p type InAlP and has a mesa stripe shape having slanted side surfaces so as to define a light waveguide channel of the semiconductor laser. Current-blocking layers are formed to cover the slanted side surfaces of the second cladding layer. The current-blocking layers comprise GaAs which is a III-V group compound semiconductor different from the III-V group compound semiconductor (i.e., InAlP) comprised in the second cladding layer. The composition ratio of aluminum in the second cladding layer is set not to be less than 0.

Abstract: There is disclosed a semiconductor layer which can emit a continuous laser beam in a visible wavelength range. The laser has an n-GaAs substrate. On this substrate, an n-InGaAlP cladding layer, an active layer, and p-InGaAlP cladding layers are sequentially formed, thus forming a double hetero-structure. A mesa-shaped, upper cladding layer is provided, defining a laser beam-guiding channel. A thin p-InGaAlP contact layer and a mesa-shaped, p-GaAs contact layer are formed on the top surface of the upper cladding layer. Two n-type semiconductive, current-blocking layers cover the slanted sides of the upper, mesa-shaped cladding layer and also the contact layer. They are made of the same n-GaAs compound semiconductor material as the substrate.

Abstract: In a radiation image recording and reproducing method wherein a plurality of stimulable phosphor sheets are reused by repeated circulation through a radiation image recording step, a radiation image read-out step, and an erasing step, each stimulable phosphor sheet is provided with its own identifying code and each time a visible image is reproduced the identifying code of the stimulable phosphor sheet on which the corresponding radiation image was stored is simultaneously reproduced, thereby enabling identification of sheets requiring replacement. The number of times each sheet is subjected to image readout is counted, and sheets are selectively removed after they circulate a predetermined number of times indicative of sheet wear out.

Abstract: Disclosed herein is a magneto-optical medium comprising a magnetic layer, a protective layer of a complex oxide containing oxides of aluminum and a base plate.

Abstract: An apparatus of the invention includes an AC power source for providing AC electric power, a thyristor converter, being formed of self-extinctive switching elements, for converting the AC electric power to a DC excitation current, a coil for storing magnetic energy corresponding to the excitation current, and a bypass circuit coupled in parallel to the coil. The above appartus uses a method having the steps of: (a) circulating the excitation current between the thyristor converter and the coil when the excitation current reaches a reference value, and (b) commutating the circulated excitation current from the thyristor converter to the bypass circuit after a given elapsed period of time from when the excitation current reaches the reference value, so that the coil generates a high voltage or induces a large current corresponding to the magnitude of the stored magnetic energy.

Abstract: A radiation image and read-out apparatus comprises a conveying means for circulating stimulable phosphor sheets along a predetermined circulation path, an image recording section for recording radiation images of objects on the sheets, an image read-out section for reading out the radiation images from the sheets, an erasing section for releasing radiation energy remaining on the sheets, a sheet position detection means for outputting sheet position data, an object data input section for receiving data related to the objects, and a signal output control circuit for receiving the object data and the sheet position data, storing the object data in association with the sheet positioned at the image recording section at the time the object data is received, reading out the object data stored in the memory means in association with the sheets at the time the radiation images are read out in the image read-out section, and outputting data signals corresponding to the object data for the respective sheets together w

Abstract: A hetero junction type semiconductor laser device is provided wherein a hetero layer is formed on a clad layer leaving a stripe shape portion. The clad layer is formed on an active layer over a substrate. At least two coating layers of the same conductivity type as the clad layer are formed on the hetero layer so as to have a current confining effect and a built-in waveguide effect. The refractive index of the coating layers which is nearer to the active layer is greater than the refractive index of the clad layer and the refractive index of the other coating layer is smaller than the refractive index of the coating layer which is nearer to the active layer. Using this construction, a low lasing threshold current is achieved.

Abstract: A gate-turn-off thyristor failure detecting circuit includes a detector which detects an off-gate signal for a gate-turn-off thyristor and a current level detector which compares the signal with a predetermined value and produces an output signal indicative of the failure of the gate-turn-off thyristor.

Abstract: A vacuum heat insulator comprises compressed glass fibers, a planar thin metal plate and a drawn metal plate. A receptacle is air-tightly formed of the planar thin plate and the drawn metal plate. The glass fibers are encased in the receptacle under a vacuum condition. A small amount of the glass fibers is penetrated thereinto in a direction perpendicular to the heat transfer direction of the insulator by inserting needles having hook portions into the glass fibers whereby the compressed glass fibers are kept under a vacuum condition at a high density without any remarkable deformation.

Abstract: A process for producing a porous film or sheet, which comprises melt-molding a composition prepared by compounding 100 parts by weight of a polyolefin resin with 25 to 400 parts by weight of a filler and 1 to 100 parts by weight of a liquid or waxy hydrocarbon polymer into film or sheet, and stretching the resulting film or sheet.

Abstract: A snubber circuit is connected between the anode and cathode of a gate turn-off (GTO) thyristor. To the GTO thyristor a saturable reactor is connected in series. A gate off signal is supplied to the gate of the GTO thyristor and to the saturable reactor as backward current to reset the saturable reactor.