An object is imaged continuously during a first exposure time and a second exposure time shorter than the first exposure time. Weights, one of which decreases monotonously and the other of which increases monotonously, are applied to first and second resultant image signals under the condition that the sum of the weights is 1. The first and second image signals that have been weighted are added up, thus producing a synthetic picture signal. When a luminance level is low, the ratio of the first i...

When a reprint of a picture which has been printed once and stored as picture image data is requested under a different condition, the reprint can be generated without carrying out rereading of a film. When film reading for generating a print is carried out, as much information showing the content of the picture image is recorded on the film as possible. This includes information which is not necessary for generating the requested print. It is stored as a portion of the picture image data. In th...

A vacuum tube includes a cylindrical cathode around which a frusto-conical control grid extends. The control grid, which is made out of Phosnic bronze, has its larger diameter end attached to the smaller end of a first hollow truncated copper cone. A cylindrical Phosnic bronze screen grid extends coaxially around the control grid. One end of the screen grid is attached to the smaller diameter end of a second hollow truncated cone. The second cone extends around the first cone and is made out of ...

An improved high power electron tube has at least one grid electrode. The grid electrode is formed from a one piece cylindrical member, closed at one end, having an outside diameter, D. The cylindrical member has a plurality of arcuate, circumferentially elongated apertures extending therethrough. Each of the apertures has a length x and a width y wherein the length x is greater than width y, and wherein the length x is not greater than 0.55 times the diameter, D, of the electrode. The width y, ...

A solid-state image pickup apparatus includes a solid-state image sensor having photosensitive cells and vertical transfer paths. The cells are bidimensionally arranged for converting light incident from a subject via optics to electric charges corresponding to the light to store signal charges. The vertical transfer paths each adjoins the photosensitive cells arranged on a particular column for vertically transferring the signal charges. Before the signal charges are transferred from the cells ...

A photographic film scanner for scanning a film strip containing a plurality of photographic images is disclosed. The film strip is advanced through the scanner and a digital image of the film strip is created. Individual images contained in the digital image of the film strip are located and displayed. The film strip is scanned at any of a variety of resolutions.

This invention relates to a roof-supporting assembly for a hydraulic roof-supporting system for longwall faces, which roof-supporting assembly comprises three frames placed side by side of which either the two outer frames jointly or the frame in the middle can be advanced and wherein the frames are coupled by paired control cylinders operable in contrary directions for correcting the relative positions of the frames, the annular piston face in one of each pair of cylinders having the same effec...

An electron tube with concentric, cylindrical electrodes has at least one meshed type of grid, a mesh being defined by several rods in contact by their ends, each point of contact forming a node. In order to limit the grid current, the surface area of a node is reduced. Only three rods leave each node. The meshes are hexagonal.

Technical-grade silicon is purified to produce silicon having less than 1 ppm of electrically effective impurities therein, particularly boron and phosphorus, by treating molten technical silicon with a hydrogen containing gas in the presence of water so as to remove such impurities from the molten silicon.

In an exemplary embodiment, a transmitting tube has a coaxial design of the electrodes and their lead-ins and includes a cathode formed of a hollow cylinder which is secured at one end to an annular cathode lead, and at the other end is secured to a cathode cap which is supported at a power supply lead extending coaxially within the hollow cylinder. In this cathode, the carrier is not to consist of wire, so that inhomogeneities on the cathode surface are avoided. To this end, the disclosure prov...