Abstract: Optical transmission lines in optical transmission systems or laser beam source-applied devices, which utilize optical fibers as optical transmission lines, are connected by optically coupling to an optical fiber terminal portion, which is configured by holding the vicinity of the optical fiber terminal portion with a capillary tube, a ferrule or the like at the connecting portions of the transmission lines. With this configuration, minimizing return loss at the optical fiber terminal portion is a key issue. As a solution thereof, a capillary tube made of glass is used; however, since insertion by driving in or press fitting to a metallic tube or the like is impossible, mass production is impossible, accurate processing is impossible, and it is costly due to the characteristics of the glass, there are many restrictions in the usage thereof.

Abstract: An impregnated cathode and a method of manufacturing the same are provided for suppressing emission of unwanted electrons and particles generated from an excess electron emitting substance so as to achieve a steady electron emission characteristic. The impregnated cathode is placed directly beneath an electron emission hole of a first grid. The impregnated cathode is made up of a first sintered porous element whose surface functions as an electron emitting region and a second sintered porous element whose surface is a peripheral region other than the electron emitting region. The porosity of the first sintered porous element is greater than that of the second sintered porous element. Not only the first sintered porous element having the electron emitting region but also the second sintered porous element corresponding to the region around the electron emitting region is impregnated with the electron emitting substance.

Abstract: An impregnated cathode and a method of manufacturing the same are provided for suppressing emission of unwanted electrons and particles generated from an excess electron emitting substance so as to achieve a steady electron emission characteristic. The impregnated cathode is placed directly beneath an electron emission hole of a first grid. The impregnated cathode is made up of a first sintered porous element whose surface functions as an electron emitting region and a second sintered porous element whose surface is a peripheral region other than the electron emitting region. The porosity of the first sintered porous element is greater than that of the second sintered porous element. Not only the first sintered porous element having the electron emitting region but also the second sintered porous element corresponding to the region around the electron emitting region is impregnated with the electron emitting substance.

Abstract: A solar-cell watch dial to be disposed on or above a solar cell housed in a watch, the solar-cell watch dial including an alumina of the formula Al.sub.2 O.sub.3 whose purity is at least 99.90% and exhibiting a light transmission ranging from 40 to 60%. The invention also includes a process for producing a solar-cell watch dial, which includes the steps of: mixing together an alumina of the formula Al.sub.2 O.sub.3 whose purity is at least 99.90%, an organic binder and water to thereby obtain an Al.sub.2 O.sub.3 mixture (A); drying and granulating the Al.sub.2 O.sub.3 mixture to thereby obtain a granular material (B); molding the granular material into a plate dial precursor (C); firing the dial precursor at 700 to 1500.degree. C. in atmospheric environment to thereby obtain a preliminary firing product (D); and firing the preliminary firing product at 1500 to 1800.degree. C. under a pressure of 1.times.10.sup.-2 to 1.times.10.sup.-5 torr for 1 to 10 hr to thereby obtain a solar-cell watch dial (E).

Abstract: A solar-cell watch dial to be disposed on or above a solar cell housed in a watch, the solar-cell watch dial comprising an alumina of the formula Al.sub.2 O.sub.3 whose purity is at least 99.90% and exhibiting a light transmission ranging from 40 to 60%. The invention also includes a process for producing a solar-cell watch dial, which comprises the steps of: mixing together an alumina of the formula Al.sub.2 O.sub.3 whose purity is at least 99.90%, an organic binder and water to thereby obtain an Al.sub.2 O.sub.3 mixture (A); drying and granulating the Al.sub.2 O.sub.3 mixture to thereby obtain a granular material (B); molding the granular material into a plate dial precursor (C); firing the dial precursor at 700 to 1500.degree. C. in atmospheric environment to thereby obtain a preliminary firing product (D); and firing the preliminary firing product at 1500 to 1800.degree. C. under a pressure of 1.times.10.sup.-2 to 1.times.10.sup.-5 torr for 1 to 10 hr to thereby obtain a solar-cell watch dial (E).

Abstract: A pair of parallel frame members 30 and 31 are formed in the inner bobbin faces of recording/reproducing and erasing coil assemblies 3, 4 on the opposite sides and spaced equidistant from a core tip center line T. An orthogonal frame member 32 is formed on the outer side of each of the bobbin end face to extend in a direction perpendicular to the parallel frame members 30 and 31. The end of the orthogonal frame member 32 extending toward an auxiliary sliding face 15 of a slider 2 extends outwardly from one of the parallel frame members 31. The recording/reproducing and erasing coil assemblies 3 and 4 are disposed asymmetrically to each other about the core tip center line T. When the recording/reproducing and erasing coil assemblies 3 and 4 are respectively housed in coil assembly receiving portions 26 and 27, the coil assemblies 3 and 4 will not extend outwardly beyond a slider plane projection line C.

Abstract: A piezoelectric oscillator comprises a piezoelectric oscillating reed, an insulating substrate for retaining the piezoelectric oscillating reed, and a cap fixed onto the top surface of the insulating substrate for enclosing the piezoelectric oscillating reed. Four connecting electrodes are formed on the top surface of the insulating substrate for electrical connection to the oscillating reed, which are divided into two groups. Each group includes two connecting electrodes which are connected to each other by metal interconnects. The insulating substrate is rectangular, and two connecting electrodes, each of which belong to one group, are located along the shorter sides of the insulating substrate. On the bottom surface of the insulating substrate, at least two external electrodes are formed, to which metal interconnects for each group are connected through the side surface of the insulating substrate.