Abstract: A photoflash unit comprising a linear array of flashlamps mounted on a printed circuit strip disposed within the longitudinal channel of an elongated housing member having an enclosing cover panel of light-transmitting material. The unit has connector terminals at opposite ends, and the linear array of flashlamps is divided into two groups disposed in opposite halves of the unit, each group of lamps being operated by the connector terminals at the remote end so as to reduce the red-eye photographic effect. The lamp-firing circuitry includes a pair of common circuit conductor runs respectively located on opposite halves of the printed circuit strip and on opposite sides of a common surface. An interconnecting jumper, or crossover, between the common circuit runs is provided through continuous conductive reflector surfaces on the housing channel which make contact with conductive deposits extending from the respective common circuit runs to the edge of the printed circuit strip.

Abstract: A hermetically-sealed pyrotechnic cap is described which includes a plastic (e.g. polyethylene) container and a quantity of pyrotechnic mixture therein. Closure of the container is achieved by heat-sealing an end thereof. A method for effecting the closure is also described.

Abstract: An improved pyrotechnic cap capable of being activated by the radiant energy from an adjacent flashlamp. The cap includes a plastic container with a quantity of pyrotechnic composition hermetically sealed therein. Receipt of the described radiant energy causes activation of the composition whereby the cap produces an audible signal of high intensity (e.g. 158 to 164 decibels at 25 centimeters). The improvement comprises adding a desiccant material within the cap's container atop the pyrotechnic composition to absorb any quantities of moisture which might enter the container and adversely affect the cap's operability.

Abstract: A multilamp photoflash unit including an elongated plastic housing having a longitudinal channel therein. Within the channel is positioned a thin, flat circuit board to which are connected several (e.g. six) flashlamps arranged in a linear array. The lamps are divided into two opposing pluralities such that those in the plurality being fired are inverted during firing.

Abstract: A photoflash unit comprising a linear array of flashlamps mounted on a printed circuit strip disposed within the longitudinal channel of an elongated housing member. A light-transmitting cover panel is attached to the housing member for enclosing the flashlamps. To prevent sympathetic ignition of adjacent lamps, the one-piece cover is molded to have integrally projecting transverse webs which function as light-attenuating partitions between respective pairs of lamps. In addition, the webs bridge the housing channel to provide structural rigidity.

Abstract: For use in a color-corrected photoflash unit, a flashlamp having a clear glass envelope with a transparent protective exterior coating comprising a UV curable photopolymer tinted with a colorant providing a portion of the total color correction capability of the unit.

Abstract: A photoflash unit comprising a plurality of high voltage type flashlamps mounted on a printed circuit board containing circuitry for sequentially igniting the flashlamps. A plurality of electrically conductive reflectors respectively associated with the flashlamps are disposed between the lamps and the circuit board, with each reflector having an aperture in alignment with a corresponding aperture in the circuit board. Connected in series with each but the last lamp of the array is a radiant-energy-activated disconnect switch comprising a strip of electrically conductive heat-shrinkable polymeric material which is attached at both ends to the circuit board so that the midportion of the strip bridges a respective one of the apertures therein. A sheet of electrically insulating material is interposed between the reflectors and circuit board to prevent shorting therebetween. A plurality of deformations, such as dimples, are formed in the insulating sheet for spacing the sheet from the disconnect switch strips.

Abstract: A photoflash lamp array comprising a plurality of high-voltage type flashlamps mounted on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive high-voltage firing pulses applied thereto. Each of the flashlamps has a pair of lead-in wires connected to the circuit board by eyelets which project through to the opposite side of the board, one lead of each lamp being connected via its respective eyelet to a common circuit conductor. Electrostatic protection is provided by a conductive shield of planar configuration disposed parallel to the circuit board and spaced therefrom on the side opposite that on which the lamps are disposed. Selected ones of the common circuit connected eyelets project from the back of the circuit board in a manner which maintains the spacing between the shield and circuit board, to prevent short circuiting of leads, and facilitates electrical connection of the planar shield to the common circuit conductor.

Abstract: A photoflash lamp having a glass envelope with a clear protective exterior coating comprising a photopolymer. In applying the coating, the lamp is dipped in a liquid photopolymer and then cure-hardened by a short period of irradiation with a source of ultraviolet light.

Abstract: A high-voltage type photoflash lamp having an ignition structure including an improved primer material with enhanced breakdown voltage characteristics for the reliable ignition of filamentary combustible material distributed within the oxygen-filled envelope of the lamp. The primer material comprises a particulate fuel such as zirconium powder, a binding agent such as nitrocellulose, and an additive of relatively coarse inert material which is nonconductive and insoluble in the vehicle used in the applied slurry. A preferred additive consists of glass microbeads having a particle size substantially larger than the zirconium powder used.

Abstract: A photoflash unit comprising a plurality of high-voltage type flashlamps mounted on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive high-voltage firing pulses applied thereto. One lead-in wire of each of the flashlamps is connected to a common circuit conductor. An electrically conductive reflector unit is positioned between the lamps and the circuit board. The reflector unit is connected to the common circuit conductor by means of a pliable, electrically conductive adhesive material, whereby the reflector unit functions as an electrical shield for the circuitry.

Abstract: A photoflash unit having a flashed lamp indicator comprising two layers of film having different colors, one of the layers being a heat-shrinkable material and the other layer being translucent and substantially unaffected by the heat of lamp flashing. An adjacent indicia sheet provides an aperture through which one of the indicator colors is visible. Upon flashing of an associated lamp, the heat shrinkable layer shrivels from view and the color of the other layer becomes visible through the aperture to clearly identify which lamp was flashed. In one embodiment, the two-color indicator is used to identify the last lamp flashed in a sequence, while each of the preceding lamps in the sequence has a respectively associated single-layer color indicator which shrinks away to leave a void upon flashing of the lamp.

Abstract: A photoflash lamp-reflector module for use in a photoflash unit having a plurality of such lamp-reflector modules arranged in a compact array. Each reflector has a substantially parabolic surface with a centrally disposed elongated cylindrical recess having a longitudinally extending central slot. The associated tubular lamp is nested within the recessed portion of the reflector, whereby an oversized lamp is accommodated by the reflector with little or no loss of light output.

Abstract: There is disclosed a multi-flashlamp article capable of providing both highly intense audible and visual signals. The article is ideally suited for use as an intrusion alarm and includes a combustible member within the assembly's light-transmittable housing. A prestressed spring actuates the combustible by deforming a tubular primer having a quantity of fulminating material therein. This deflagrating material ignites a second quantity of fulminating material within the combustible's container to effect a suitable audible signal.

Abstract: A photoflash unit comprising a plurality of high-voltage type flashlamps mounted on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive high-voltage firing pulses applied thereto. One lead-in wire of each of the flashlamps is connected to a common circuit conductor. Electrostatic protection is provided by a conductive array of reflectors positioned between the lamps and one side of the circuit board and a planar shield of conductive material disposed parallel to and spaced from the opposite side of the circuit board, both the reflector array and shield being electrically connected to the common circuit conductor and thereby effecting a static "grounding" system. The assembly is enclosed in a plastic housing having a light-transmitting side wall adjacent to the flashlamps.

Abstract: A multilamp photoflash assembly comprising a housing defining two adjacent regions therein, a plurality of flashlamps within one of said regions having at least one pre-energized striking mechanism associated with each of said lamps, and a rotatable actuating member for sequentially actuating each of the striking mechanisms and thus cause firing of the lamps. In another embodiment, there is disclosed a photoflash assembly wherein a plurality of flashlamps are located within both of said regions and a single actuator is used. In still another embodiment, both regions of the support member are occupied with flashlamps and a pair of rotatable actuators are employed.

Abstract: A photoflash lamp having an ignition filament composed of a combustible metal, such as zirconium, hafnium, or titanium, to assure reliable lamp operation from low current power sources. In miniature high pressure lamps, the combustible filament may be employed as the sole ignition source, without the need for primer beads.

Abstract: A photoflash unit having a plurality of high voltage type flashlamps mounted in a planar array on a printed circuit board containing circuitry for sequentially igniting the flash lamps in response to successive high voltage firing pulses applied thereto. The circuitry includes a plurality of solid state switches capable of being easily activated by radiant energy generated during flashing of the lamps. Initially, the switches have a high resistance, and after being activated by radiation, they undergo chemical conversion to a conductive state. The switches are prepared from compositions particularly resistant to high relative humidity and above normal ambient temperatures. The switch material composition comprises silver carbonate, a binder such as polystyrene resin, and an oxidizer such as barium chromate.