摘要:
A modified lead barium titanate ceramic which has a fundamental composition of (Ba.sub.1-x-y Sb.sub.y Pb.sub.x)TiO.sub.3, where x is not greater than 0.9 and usually not smaller than 0.6 and y is from 0.001 to 0.1, and has a high positive temperature coefficient of resistivity (PTCR) over a range of temperature higher than about 350.degree. C. at the lower boundary, is produced by using a metal salt of an organic acid such as lead titanate salt of oxalic acid as the source of Pb and by adding at least one of BaCO.sub.3, SiO.sub.2, BN and TiO.sub.2 to the raw materials of the above fundamental composition. After thermally decomposing the organic acid metal salt the mixture of the raw materials including the additive(s) is compacted and sintered. By this method the sintering is achieved with good reproducibility and with little dissipation of lead, and the obtained titanate ceramic is good and durable in the PTCR characteristics and hence is useful as the material of a PTC thermistor functioning at medium-to-high temperatures.
摘要:
A mode selecting device for use in a camera provided with the various picture taking modes including standard picture taking mode, self-timer picture taking mode, flash light picture taking mode, close picture taking mode, fill in flash mode, nonflash mode and consecutive picture taking mode. A mode setting button is operable to select the mode and a memory is provided to store data corresponding to the selected mode. Also disclosed is a brightness measuring circuit and an automatic exposure control circuit. A flash is enabled or disabled in accordance with the mode selected and the measured brightness value. The camera is automatically reset to the most frequently used mode for emitting the flash light automatically under low light condition after a exposure has been completed, or a given time after the exposure has been completed. Additionally, a warning indicator is actuated when it is detected that the rear lid has been opened and film is mounted in the camera, and a display is provided to indicate the presence of film in the camera when a warning signal has been stored.
摘要:
A focus detecting device for detecting a focus condition of a photographic lens by receiving light coming from a plurality of focus detecting area and auxiliary illuminating device therefor. The illuminating device is provided with a light source, a projection pattern disposed just before the light source for providing a sufficient contrast onto an object and a projection lens. The light source is composed of plural condenser lenses arranged in a row and plural light emitting elements arranged behind the condenser lenses at intervals wider than the spacing of adjacent condenser lenses, whereby an object of a wide range is illuminated uniformly. The projection pattern comprises small-size patterns suitable for photographic lenses of long focal lengths, arranged centrally of the projection pattern, and large-size patterns suitable for photographic lenses of short focal lengths, arranged in the outer peripheral portion of the projection pattern. Further, the projection pattern has a curved shape to compensate astigmatism characteristics of the projection lens.
摘要:
A changeable focal length photographic camera which may operate in either a real focal length photographing mode or a pseudo focal length photographing mode. A light shielding device shields a portion of the film to be exposed when the pseudo focal length photographing mode is selected.
摘要:
A photographic camera system including a mode setting device for selectively setting the system to a real focal length photographing mode for printing an ordinary photographic zone and a pseudo focal length photographing mode for printing a zone narrower than the ordinary photographic zone, a recording device for recording on a film information corresponding to a set one of the photographing modes, a data imprinting device for imprinting data such as date at one of different positions on a photographing portion of the film and a selector device for selecting the one of the different positions in accordance with the set one of the photographing modes.
摘要:
An electronic appliance having a microcomputer, peripheral devices controlled by the microcomputer, a main battery acting as power source, and a backup battery for outputting signals indicating the presence and absence of the main battery. Checking is made of whether the main battery is loaded in the appliance or not and whether the output voltage of the main battery is above a predetermined voltage or not. When the main battery is not loaded or when its output voltage is below the predetermined voltage, the backup battery is made available for preserving information in the memory inside or outside the microcomputer in good order, with operations of the peripheral devices being restricted at such times. Further, the disclosed electronic appliance provides for limiting malfunctioning of the microcomputer and the peripheral devices when a new main battery has been loaded in the appliance as replacement for an exhausted main battery.
摘要:
The photographic camera which prints a code signal representing printing information on a film is capable of selecting a real focal length photographing mode for printing a normal range of a frame a, plurality of pseudo focal length photographing mode each being different in pseudo focal length from the other, and a close-up photographing mode. Exposure condition is limited in accordance with the selected mode. Upon selection of the photographing modes, a code signal indicative of said selection is produced and printed between frames on the film surface. The film after photographing with this camera is subjected to printing by means of a printer which reads the code signal printed on the film surface, determines an exposure value in accordance with the code signal and determines an enlargement ratio.
摘要:
A camera having, in addition to a real focal length photographing mode, a pseudo focal length photographing mode, namely, a photographing mode in which a part of a photographed image frame of a film is printed at an enlarging ratio different from an ordinary enlarging ratio to obtain a print as if it had been photographed using a telephoto lens. It is provided with means for recording photographing mode information on a frame of a film when the pseudo focal length photographing mode is selected, and a control means which brings a flash light emitting device into an operable condition in response to the selection of the pseudo focal length photographing mode and which actuates the flash light emitting device in synchronism with release of the shutter. An optical axis of a photographing lens and a flash emission tube are spaced from each other, and the pseudo focal length photographing mode can be selected only when a negative film is loaded in the camera.
摘要:
A dustproofing mechanism for a thin, disc film cartridge type camera having windows in its front wall for the camera viewfinder and objective lens includes a cover structure guided for movement to alternative positions opening or closing both windows and an operating member accessible through one of the windows is connected to the cover structure to permit the manual selective movement of the cover structure to the window open or closed position.
摘要:
A single lens reflex camera includes a vertical open topped U-shaped bracket mounted in the camera body below the pentaprism, a forwardly located lens mount separably coupled to an objective lens and pairs of links mutually pivoted between their ends connected between the bracket arms and corresponding edges of the lens mount to support the latter in a fixed orientation for linear longitudinal movement along the camera optical axis. A light tight collapsible conduit extends between the camera body and lens mounts and includes telescoping members with relatively slidable side and bottom walls and an accordian top wall. A rack carrying slide arm projects rearwardly from the lens mount and is engaged by a motor driven gear to longitudinally shift the lens mount. The motor is controlled manually or in response to a focus detecting device and the lens mount may be motor advanced and retracted or motor advanced and spring retracted. The lens diaphragm is automatically stopped down by a camera housed mechanism and diaphragm control information is transmitted from the lens mount to the camera body.