Abstract: Techniques are described for treatment of ash and paper to eliminate them from the environment and to produce ceramic particles useful as light-weight aggregate (e.g., for use in concrete products). The ash may be that resulting from incineration of rubbish or sewage sludge or it may be fly ash from power plants. The ash and waste paper are mixed with clay and water, shaped into desired shapes and sizes, after which the particles are fired to produce ceramic particles which are lighter in weight than natural aggregates.

Abstract: An improved electrical circuit for controlling the firing time of an electronic flash tube. The electrical circuit includes a storage capacitor that is chargeable by a suitable power source, a flash tube and an insulated gate bipolar transistor (IGBT), which can be activated between conductive and non-conductive states, that is connected in the discharge path of the storage capacitor through the flash tube. A signal responsive to a flash firing command is applied to the flash tube to initiate flash tube firing after the IGBT has been activated from its non-conductive to its conductive state. A flash terminating command is subsequently applied to the IGBT to terminate flash firing. The flash firing command and the flash terminating command are made independent of one another. By making these commands independent of one another, any undesirable effects of one or more electrical characteristics of the IGBT on flash tube firing is thereby eliminated.

Abstract: Electronic flash apparatus is provided that is capable of reducing the incidence of eyelid closure of a subject during an exposure interval when the subject is illuminated with visible light from the electronic flash apparatus immediately prior to the exposure interval. The electronic flash apparatus includes a visible light flash tube and an electrical circuit coupled thereto for controlling flash tube energization and de-energization immediately prior to and during an exposure interval. The electrical circuit includes apparatus for coupling the flash tube to a suitable source of electrical energy and for applying a trigger signal to the flash tube in order to illuminate the subject with a finite amount of visible light immediately prior to an exposure interval that will not cause the eyelids of the subject to blink in response thereto during the exposure interval.

Abstract: Processes and techniques are described for treating waste water (domestic and industrial) to remove organic matter and heavy metals. Clay and flocculating agent are added to the waste water to cause separation of a sludge. The sludge is fired at high temperature in particle form to produce ceramic particles. Organic matter is oxidized; heavy metals are bound within the ceramic particles and cannot leach out. The ceramic particles are useful as aggregate (e.g., in concrete) and in landscaping.

Abstract: A black, infrared pass filter is disposed in front of the strobe element of an automatic rangefinding camera to provide an infrared ranging wink for ranging during the pre-exposure steps of a camera cycle. As the cycle continues, the filter is temporarily displaced from in front of the strobe element to allow a visible light, flash firing for scene illumination. Once the exposure firing is complete, the filter resumes its original position in front of the strobe element such that the filter allows only infrared light to be transmitted from the strobe element except during exposure strobe firing.

Abstract: Biological stable articles are described which are especially useful as bed materials for treating waste water. Preferred articles are charred rice hulls which comprise silica and carbon.

Abstract: A DC-to-DC converter charges a capacitor connected to the secondary of a transformer having a primary connected to a low-level power supply through an input control circuit which, when triggered, connects the power supply to the primary for only a predetermined time interval whereby current flows in the primary establishing a magnetic field that stores energy derived from the power supply. When the current in the primary is interrupted, the field collapses, inducing current to flow in the secondary thereby transferring energy from the field to the capacitor. The control circuit is triggered by a voltage sensor that detects the collapse of the field to zero. The voltage sensor includes a sensor inductively coupled to the magnetic field for developing a sensed voltage having a first level during collapse of the field and a second level after the field collapses to zero, the breakpoint between the levels defining the instant at which the field collapses to zero.

Abstract: Electronic flash apparatus for a camera having automatic focusing with sonic ranging has a charge control system which inhibits charging of the flash tube capacitor during at least the automatic focusing operation of the camera. The flash apparatus thus schedules capacitor charging to occur at times other than the sonic ranging for automatic focusing, and thereby avoids the likelihood that spurious radiation from the capacitor-charging oscillator interferes with the sonic ranging operation.

Abstract: A self-developing camera with automatic focusing has a charge control system which charges the flash tube capacitor while other camera functions are inactive, and which disables capacitor charging during automatic focusing and during the film-related operations of exposure, transport, and processor-spreading. An enabling stage allows flash-illuminated exposure only when the storage capacitor is properly charged. The charge control system thus schedules high current operations to occur one at a time so that a single battery can power all camera operations. Further, it inhibits exposure under conditions of inadequate flash readiness. The control system affords the user of an SLR camera with a viewing interval between automatic focusing and exposure.

Abstract: Unique fired clay pillows are described which are useful for a variety of purposes. They have particular utility in structural applications when they are first rendered impervious, mixed with a hardenable binder, and then cast into a mold or form of desired size and configuration where the binder is hardened, thereby producing a consolidated pillow structure having a high degree of void space. The consolidated pillow structure is fire-resistant, weather-resistant, rot-proof, and exhibits good sound absorption and thermal insulation properties.

Abstract: A simplified voltage regulating circuit is provided for controlling the operation of a d-c to d-c converter oscillator as is commonly used in an electronic flash. The voltage regulating circuit controls the operation of the d-c to d-c converter so that the output voltage from the oscillator is maintained within a prescribed range. The voltage regulating control circuitry includes an ordinary transistor controlled by way of an output voltage sensing zener diode which operates to turn on the transistor and thereby terminate operation of the oscillator when the output voltage therefrom reaches its maximum value within the prescribed range. A capacitor is also charged by way of the transistor when it turns on and the residual charge of the capacitor thereafter operates regardless of the non-conductive state thereafter assumed by the zener diode and transistor to maintain the oscillator off until the output voltage from the oscillator decays to its minimum value within the prescribed range.

Abstract: A quench strobe is provided with a resistor for effecting the quenching thereof at a predetermined rate which controls the amount of exposure influencing artificial illumination emitted subsequent to the quench trigger signal so that such exposure influencing artificial illumination closely correlates to the amount of exposure influencing illumination normally expected subsequent to the command signal to close the camera shutter blade elements and automatically anticipated by the camera exposure control system.

Abstract: Electronic flash apparatus for a camera having automatic focusing with sonic ranging has a charge control system which inhibits charging of the flash tube capacitor during at least the automatic focusing operation of the camera. The flash apparatus thus schedules capacitor charging to occur at times other than the sonic ranging for automatic focusing, and thereby avoids the likelihood that spurious radiation from the capacitor-charging oscillator interferes with the sonic ranging operation.