Abstract: An apparatus for reducing noise component contained in an input signal has: a detecting device for detecting a level of the noise component; an adjusting device for adjusting a level of the input signal so as to make the level of the noise component equal to or lower than a predetermined threshold level; a reducing device for reducing a signal component of the adjusted input signal whose level is equal to and lower than the predetermined threshold level; and a restoring device for restoring a level of the adjusted input signal to the level of the input signal that has not been adjusted by the adjusting device yet.

Abstract: An input signal from an audio system is divided into a plurality of frequency bands, and the signal in each frequency band is attenuated by an attenuator. The output signals of the attenuators are added. A level of the signal in each frequency band is detected by a level detector. A memory is provided for feeding an attenuation dependent on a level detected by the level detector. A controller is provided for controlling a signal attenuation of the attenuator by an attenuation fed from the memory in accordance with a detected level.

Abstract: A method of controlling a bias current required to record an audio signal on a recording medium includes the steps of: recording a test signal having a frequency component higher than a predetermined frequency on the recording medium and reproducing the recorded test signal from the recording medium; determining a reference amount of the bias current variation on the basis of the level of the reproduced test signal; determining a bias current variation characteristic of the recording medium on the basis of the reference amount; and varying the bias current in accordance with a level change of a high frequency component of the audio signal by referring to the bias current variation characteristic during a recording of the audio signal.

Abstract: Method and apparatus automatically select, in a playback mode, a noise reduction circuitry of a noise reduction system by which a middle-to-high frequency signal of a low level included in a recording signal is compressed in dynamic range for recording and the compressed middle-to-high frequency signal is expanded in dynamic range in the playback mode, thereby suppressing middle to high frequency noises in the reproduction signal. A level difference .DELTA.L between the maximum and minimum signals of the low frequency component in the reproduction signal and a level difference .DELTA.H between the maximum and minimum signals of the middle-to-high frequency component in the reproduction signal are obtained. While comparing the magnitudes of the two level differences obtained, the selection of an appropriate noise reduction circuitry is performed so that the two level differences are made almost equal to each other.

Abstract: An X-ray image pickup tube converts a transmitted X-ray image into electric signals. The pickup tube includes a target structure having a fluorescent element, and a translucent conductive film for receiving a high voltage, with a photoconductive film laminated thereupon. The fluorescent element receives transmitted X rays in a two-dimensional distribution, and converts them into visible rays in a two-dimensional distribution. The translucnet conductive film is optically coupled to a surface of the fluorescent element opposite from an X-ray incident surface thereof. The photoconductive film includes an amorphors semiconductor layer which converts the visible rays transmitted in a two-dimensional distribution through the translucent conductive film, into electric charges in a two-dimensional distribution, and which multiplies the electric charges in the two-dimensional distribution based on electric fields formed by the high voltage applied to the translucent conductive film.

Abstract: A two-dimensional radiation detector for obtaining a radiographic image as converted into electric signals. The detector has a multi-layer structure including a scintilator, a translucent electrode film, a photoconductive film and a scan switch layer. The scan switch layer includes conductors arranged in matrix form and in contact with the photoconductive film, a plurality of FETs corresponding to the conductors arranged in matrix form, and a uniformly planar conductor for successively applying a bias voltage through the FETs to the matrix conductors row by row. Each FET has a drain electrode connected to one of the matrix conductors, a source electrode connected to the uniformly planar conductor, and a gate electrode connected to the drive circuit. The translucent electrode film includes column conductors corresponding to columns of the matrix conductors, each of the column conductors being connected to a signal reading line.

Abstract: An image pick-up tube and a method of fabricating an image pick-up tube and a target section used therewith, in which the target includes at least a conductive film and a photoconductive film on a substrate for photo-electric conversion, and a signal from the target section is read by an electron beam scanning system. At least a part of the surface area outside the effective scanning region of the electron beam scanning side of the target section is formed of a secondary electron emission dampening layer.

Abstract: A method of making an image pickup tube target (FIG. 1A), etc., using an amorphous photoconductive layer. When an electrode, an amorphous semiconductor layer, etc., are provided on a substrate, the steps of ion etching away a surface of the substrate and forming the electrode are performed so that a target (FIG. 1A) is produced in which no defects are substantially caused in a reproduced image even if a high electric field is applied across the target.

Abstract: A target of an image pickup tube, having a transparent substrate, a transparent conductive film, a p-type photoconductive film made mainly from amorphous Se, and an n-type conductive film capable of forming a rectifying contact at the interface with the p-type photoconductive film, using the rectifying contact as a reverse bias, characterized in that the p-type photoconductive film containing at least a region having more than 35%, and to 60% by weight of Te in the film thickness direction, and at least a region containing 0.005 to 5% by weight of at least a material capable of forming shallow levels in the amorphous Se in the film thickness direction, has good after-image characteristics even if operated at a high temperature.

Abstract: The invention relates to cathodic electrodes for use in the electrolytic treatment of alkali halide. The electrode has a substantial mass of copper or copper alloy, and the surface of the mass is roughened and activated by blasting solid and abrasive particles against the mass surface. The roughened surface is then coated with a rhodium or rhodium alloy layer. The effect is a substantial reduction of hydrogen superpotential value.

Abstract: This invention relates to an apparatus for the electrolytic treatment of alkali halide solution in a three chamber type electrolytic bath assembly comprising an anodic chamber, an intermediate chamber and a cathodic chamber arranged one after another in series. Each chamber is from its neighboring chamber by means of a cationic permselective membrane. The apparatus is characterized, according to this invention, in that the first one of the membranes separating the intermediate and anodic chambers is made of a fluorine-containing resin, while the second membrane separating the intermediate and cathodic chambers includes, as its main ion exchange radial, a pendant type phenolic radical or derivative thereof. The inventive process, which utilizes the above-described apparatus is characterized in that it utilizes a caustic alkali concentration in the intermediate chamber which ranges from about 10-20 wt.

Abstract: This invention relates to an apparatus for the electrolytic treatment of alkali halide solution in a three chamber type electrolytic bath assembly comprising an anodic chamber, an intermediate chamber and a cathodic chamber arranged one after another in series. Each chamber is separated from its neighboring chamber by means of an anodic ion exchange membrane. The apparatus is characterized, according to this invention, in that the first one of the membranes separating the intermediate and anodic chambers is made of a fluorine-containing resin, while the second membrane separating the intermediate and cathodic chambers includes, as its main ion exchange radical, a pendant type phenolic radical or derivative thereof. The inventive process, which utilizes the above-described apparatus characterized in that it utilizes a caustic alkali concentration in the intermediate chamber which ranges from about 10 - 20 wt.

Abstract: In an electrolytic treatment of alkali halide for the manufacture of alkali hydroxide, a three-chamber type reaction vessel assembly is used so as to provide an anodic chamber, an intermediate chamber and a cathodic chamber arranged in succession one after another and mutually separated by means of anodic (i.e., cationic selective) ion exchange membranes. From the intermediate chamber, low concentration caustic alkali solution is obtained, while from the cathodic chamber, high concentration caustic alkali solution is obtained. In this electrolytic process, the system is operated with the cathodic chamber supplied with no water or aqueous content. The high concentration caustic alkali solution is made from water and alkali metal ions conveyed from the intermediate chamber to the cathodic chamber and exclusively and osmotically passed through the anodic ion exchange membrane. The polymers or copolymers of the anodic ion exhange membrane include sulfonic acid, carboxylic acid and/or phenolic radicals.