Abstract: The present example provides a flexible and compact system for diffusing light in multiple levels when taking photographs. An adapter capable of coupling many types of flashes is fitted to a first diffusion device. The diffusion device may be fitted inside a light box fitted with a diffusion lens so that additional light dispersion is provided. The light box may be substituted with a black box that tends to direct diffused light for further control over exposure. Various filters may also be used in the system allowing for further flexibility in setting exposure. And finally a system of reflectors and shields allow further control of lighting effects.

Abstract: Projection device failure may be diagnosed by sensing improper operation of projection lamp ignitor circuitry. An ignitor failure indicator may be activated based on a sensed failure in the operation of the lamp ignitor circuitry to prevent incorrect projection lamp failure notification.

Abstract: An ultra high intensity flash cartridge is provided for light guns. The ultra high intensity of the flash is obtained by sealing fast burning filaments of magnesium inside a glass bulb containing pure oxygen gas under pressure. The flash is triggered by an electric current. The intensity is boosted by designing the rear surface of the bulb with a paraboloidal shape and coating it with a reflective surface so that all the light is projected and concentrated in the forward direction without requiring any external reflector. Guide flanges are built into the bulb to maintain proper orientation when loaded into a light gun. The cartridge is capable of generating a light flash several orders of magnitude brighter than the noon-day sun for temporarily blinding an assailant at a distance.

Abstract: A hand-held multiple-shot flash generator is presented for temporarily blinding an assailant at a distance. The light is generated by a plurality of ultra high intensity flash bulbs containing a fast-burning substance such as magnesium sealed in pressurized pure oxygen that is triggered by an electric current. A portion of the glass bulbs is coated with a reflective surface to concentrate and project the light flash in a forward direction. The intensity of the flash striking the eyes is sufficiently strong to cause temporary blindness, thereby rendering the assailant mobile. The flash bulbs are mounted in a cylindrical housing containing a battery and a bulb firing and ejection system designed to give repetitive operation.

Abstract: A multilamp photoflash array responsive to either a relatively high or relatively low pulse potential includes normally open (N/O) switches formed from an admixture including silver carbonate and/or silver oxide, titanium dioxide, a blended binder and a sulfur compound in the range of about 0.001 to 5.0 percent by weight and selected from the group consisting of elemental sulfur and low solubility sulfides.

Abstract: A multilamp photoflash array responsive to either a relatively high or relatively low pulse potential includes normally open (N/O) switches formed from an admixture including sliver carbonate and/or silver oxide, titanium dioxide, a blender binder and aluminum hydroxide. Also, enhanced results are provided by the inclusion of a sulfur compound in the range of about 0.001 to 5.0 percent by weight within the admixture.

Abstract: In a multilamp flash assembly adapted for attachment to a camera having a flashlamp firing circuit, the respective flashlamps are advanced sequentially to a firing position. A lamp advancing member in the flash assembly is made of an electrically conductive material and is disposed to form an integral part of the firing circuit when the flash assembly is attached to the camera. The advancing member is movable to establish an electrical connection with the respective flashlamps, one at a time, and to advance a flashlamp electrically connected with the advancing member to the firing position. Thus, the advancing member operates as an electrical contact for a flashlamp, as well as for advancing the lamp to the firing position.In an alternate embodiment, the advancing member is disposed in the camera.

Abstract: An improved multiple flashlamp array is disclosed having a plurality of low voltage type lamps fired individually and in sequence by means of a plurality of static solid switching devices capable of reliable actuation by radiant energy generated during flashing of the lamps. Initially, these switching devices have a high electrical resistance ("off position") and after being actuated by the heat and light radiation, they undergo chemical conversion to an electrically conductive state ("on position"). The switch devices are prepared in a conventional manner from a particulate mixture of silver oxide with oxidized copper metal and which further contains a particular organic polymer binder mixture. The low voltage flashlamps being fired in this manner require that the converted switch devices exhibit an electrical resistance after conversion not to exceed about 0.3 ohms.

Abstract: A multilamp photoflash array and fabrication process is provided wherein electrically conductive leads of a plurality of flashlamps are embedded in and wrapped about the ends of a plastic reflector unit which is, in turn, affixed to a circuit board to provide contact between the bent leads and a printed circuit on the circuit board.

Abstract: A multilamp photoflash array and fabrication process is provided wherein electrically conductive leads of a plurality of flashlamps are embedded in and wrapped about the ends of a plastic reflector unit which is, in turn, affixed to a circuit board to provide contact between the bent leads and a printed circuit on the circuit board.

Abstract: A multiple flashlamp array is disclosed having a plurality of lamps fired individually and in sequence by means of a plurality of static solid switching devices capable of reliable actuation by radiant energy generated during flashing of the lamps. Initially, these switching devices have a high electrical resistance ("off position") and after being actuated by the heat and light radiation, they undergo chemical conversion to an electrically conductive state ("on position"). The switch devices are prepared in a conventional manner from a particulate mixture of silver oxide with a metal exhibiting both thermal and electrical conductivity but which does not react exothermally with said silver oxide. A binder mixture is used which includes a conventional organic polymer binder which serves as a fuel during conversion of the silver oxide together with a second organic polymer binder which is more resistant to combustion.

Abstract: A moisture barrier for radiation-responsive switches which includes an admixture of particles and forms a part of a multilamp photoflash array comprises a thin, radiation-transparent and/or translucent coating which is absorbed into the switches and envelopes the individual particles of the admixture.

Abstract: A photoflash unit comprising a plurality of 2n flashlamps attached to a printed circuit board and disposed in a linear array with the longitudinal axes of respective lamps aligned in parallel. Circuit patterns on the circuit board include a plurality of n selective terminal means, each associated with a respective pair of the lamps and connected to one lead-in wire of each of the lamps of the associated pair, and a common terminal associated with all of the 2n lamps but directly connected to the other lead-in wire of one lamp of each pair. Groups of circuit pattern extensions are located behind alternate lamps of the array, the first group comprising two spaced apart segments and the remaining groups each comprising three spaced apart segments. Each group of segments is covered with a mass of radiation sensitive switch material to thereby provide respective solid state switches between bridged segment gaps which are activated upon receiving radiant energy emitted by an adjacent lamp.

Abstract: A miniaturized multilamp photoflash includes a reflector member disposed within a plastic cover and having a plurality of cavities each containing a flashlamp and a pair of spaced leg members formed for engagement within a camera. A planar support platform is affixed to the reflector member and has a printed circuit on a surface adjacent the reflector member and a tab portion wider than the spaced leg members whereby insertion of the tab portion into a receiving socket is controlled by the width of the tab portion.

Abstract: In a subminiature multilamp photoflash array having a plastic reflector member formed to provide a plurality of cavities each having a flashlamp therein and a flexible back portion, the electrical leads of the flashlamp pass through the reflector member and are positioned intermediate the flexible portion thereof and a printed circuit on a circuit board affixed to the reflector member.

Abstract: A miniaturized multilamp photoflash array having a plurality of flashlamps affixed to a printed circuit on the inner surface of a circuit board with a continuous strip of switching material forming a plurality of normally closed (N/C) switches coupling the flashlamps to a common conductor and a plurality of normally open (N/O) switches coupling all but one of a plurality of flashlamps to an energizing conductor.

Abstract: An improved quick-disconnect switch for use in a multilamp photoflash unit containing a plurality of flashlamps and circuit means for sequentially igniting the flashlamps, in which the switch is adapted to automatically by-pass a flashlamp having an improper atmosphere therein, referred to herein as an "air" or "vacuum" lamp. The disconnect switch comprises a length of polymeric material which is rendered electrically conductive by a deposit of conductive material (e.g., aluminum) on at least a portion of the surface thereof. The conductive material has a gap disposed therein extending substantially transverse to the length thereof. The disconnect switch is severed directly by ignition of the primer from the high voltage pulse that ignites the lamp rather than by previously required direct optical energy coupling from the lamp. In an alternate embodiment, the switch may be constructed of a thin, low melting alloy member.

Abstract: A miniaturized multilamp photoflash array includes an envelope with a printed circuit of spaced electrical conductors on an inner surface, a plurality of flashlamps each having a pair of electrically conductive leads and a reflector unit affixed to the envelope and having a formed member forcing the conductive leads against the printed circuit and a sonic projection sealed to the envelope intermediate the spaced electrical conductors of the printed circuit.

Abstract: A flashlamp unit for individual and sequential firing of flashlamps includes a pair of flashlamps connected in an electrical circuit with a radiation-responsive N/O arc gap switch in series connection with one of said pair of flashlamps and including an arc gap having a radiation-responsive material thereover and therebetween.

Abstract: A sequentially operable multilamp photoflash array includes a plurality of radiation-responsive normally open (N/O) connect type switches which are prepared from a composition which includes a filler material, a binder, silver coated particulate solids and silver-salt coated particulate solids. The switches are fabricated by a process wherein the silver coated particulate solids are stirred in potassium permanganate, added to an admixture of silver coated glass beads, a filler material and an organic binder and deposited onto a printed circuit board.

Abstract: A photoflash unit comprising a plurality of 2n flashlamps attached to a printed circuit board and disposed in a linear array with the longitudinal axes of respective lamps aligned in parallel. Circuit patterns on the circuit board include a plurality of n selective terminal means, each associated with a respective pair of the lamps and connected to one lead-in wire of each of the lamps of the associated pair, and a common terminal associated with all of the 2n lamps but directly connected to the other lead-in wire of one lamp of each pair. The circuit board has a substantially rectangular portion with n spaced apart extensions projecting vertically from a longer side thereof, the extensions being located behind alternate lamps of the linear array.

Abstract: A photoflash unit comprising a plurality of 2n flashlamps attached to a printed circuit board and disposed in a linear array with the longitudinal axes of respective lamps aligned in parallel. The circuit board has a substantially rectangular portion with n spaced apart extensions projecting vertically from a longer side thereof, the extensions being located behind alternate lamps of the linear array. Each extension contains portions of circuit patterns bridged by a mass of switch material to provide a solid state radiation switch on each extension and adjacent to a respective lamp for receiving radiant energy emitted by that lamp. The unit further includes a plurality of reflector cavities within each of which a respective one of the flashlamps is nested. Each reflector cavity includes a recessed rear wall section for accommodating a circuit board extension, such that each of the extensions are disposed between a respective lamp envelope and the recessed rear wall of the associated reflector.

Abstract: A photoflash lamp array having a plurality of 2n flashlamps, a common terminal connected to one lead-in wire of each of the lamps, and a plurality of n selective terminal means, each associated with a respective pair of the lamps and directly connected to the non-common lead-in wire of one lamp of each pair. A respective normally open switch is coupled between the non-common lead-in wires of each of the pairs of lamps associated with a selective terminal. Each of the switches is responsive to the flashing of the directly connected lamp of an associated pair so as to electrically connect the other lamp of the pair to the associated selective terminal. In one specific example, ten lamps are selectively paired to be operated sequentially by firing pulses successively applied to five selective terminals together with a common terminal.

Abstract: A multiple photoflash unit of the planar array type having a composite circuit board and electric shield member to which a plurality of flash lamps are electrically connected for sequential flashing with reduced possibility of accidental flashing due to electrostatic voltage charges. In a preferred embodiment the associated members are sandwiched between front and back housing covers in a manner permitting the flash lamps to generate a mechanical spring action for additional physical support in the assembly.

Abstract: A photoflash unit having a plurality of flashlamps mounted in a planar array on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive firing pulses applied thereto. The circuitry includes a plurality of solid state switches capable of being activated by radiant energy generated during flashing of lamps located adjacent to respective switches. Initially, each of the switches has a resistance sufficiently high to provide an open circuit to the applied firing pulses, and after being activated by radiation, the switch undergoes chemical conversion to a conductive state. The switches are prepared from compositions which include a selected proportion of silver-coated glass beads to consistently assure a predetermined low resistance after conversion and maintenance of good adherence and electrical contact with the printed circuit board circuitry.

Abstract: A photoflash lamp array comprising a housing elongated vertically and containing elongated flash lamps lying horizontally and stacked vertically, the flash lamps having lead-in wires extending from ends thereof near the sides of the housing and connected to a circuit board located behind the lamps. A conductive sheet-like shield is positioned between the circuit board in the rear of the housing and is contoured to have side portions extending forwardly in between lamp ends and the sides of the housing. The front surface of the shield is both electrically conductive and reflects light with electrically insulated flash indicator material being positioned on said front surface but not extending to the side portions thereof. By increasing the light reflective surface of said shield member in this manner there is increased light output obtained from said lamp array.

Abstract: A multi-flash lamp array includes a plurality of flash lamps interconnected in pairs so that the second flash lamp of each pair is fusably connected to fire during the next exposure in response to the firing of the first flash lamp of that pair. If the first flash lamp of the pair should fail to fire and thereby fail to fusably connect the second flash lamp of the pair, there is provided a redundant fusing arrangement whereby the second flash lamp of the pair is subsequently fused in connection to fire during the next exposure in response to the firing of the first flash lamp in the next succeeding pair of flash lamps to be fired.

Abstract: A photoflash unit comprising a horizontal linear array of flashlamps enclosed within a one-piece housing member having a light-transmitting front portion folded over a back portion containing a plurality of lamp-receiving cavities in which respective lamps are disposed. A printed circuit board is joined to the housing member, and a pair of lead-in wires from each of the lamps are connected to conductive circuit patterns disposed solely on one side of the circuit board. The circuit patterns include a plurality of connector terminals which are located adjacent one another on a flat tab which projects from one edge of the circuit board for insertion into the receiving socket of a firing pulse source. The tab contains a plurality of symmetrically disposed apertures or recesses which render the tab releasably engageable by socket means independent of firing pulse contacts for securely retaining the unit in the socket.

Abstract: A photoflash unit comprising a horizontal linear array of photoflash lamp enclosed within a one-piece housing member having a light-transmitting front portion folded-over a back portion containing a plurality of lamp-receiving cavities in which respective lamps are disposed. The housing is a formed sheet of plastic film having a linear fold disposed horizontally along the top of the array of cavities. A pair of lead-in wires from each of the lamps are connected to conductive circuit patterns on one side of a printed circuit board sandwiched between a set of tabs which run along the bottom of the front and back portions of the housing. The housing tabs are secured together and to the circuit board by a plurality of staples symmetrically disposed along the tabs.

Abstract: A photoflash unit comprising a horizontal linear array of flashlamps enclosed within a one-piece housing member having a light-transmitting front portion folded over a back portion containing a plurality of lamp-receiving cavities in which respective lamps are disposed. The housing is a formed sheet of plastic film having a linear fold disposed horizontally along the top of the array of cavities, which are selectively aluminized to provide a reflective coating on the cavity surfaces. A pair of lead-in wires from each of the lamps are connected to conductive circuit patterns on one side of a printed circuit board sandwiched between a set of tabs which run along the bottom of the front and back portions of the housing and are secured together.

Abstract: A photoflash unit comprising a horizontal linear array of flashlamps enclosed within a one-piece housing member having a light-transmitting front portion folded-over a back portion containing a plurality of lamp-receiving cavities in which respective lamps are disposed. The housing is a formed sheet of plastic film having a linear fold disposed horizontally along the top of the array of cavities, which are aluminized to provide a reflective coating on the cavity surfaces. A pair of lead-in wires from each of the lamps are connected to conductive circuit patterns on one side of a printed circuit board sandwiched between a set of tabs which run along the bottom of the front and back portions of the housing. The bottom periphery of the housing is secured together by means of a plurality of staples having legs which extend through the front and back tabs of the circuit board and are clinched onto the exterior surface of the front tab.

Abstract: A photoflash lamp array having a plurality of 2n flashlamps, a plurality of n selective terminal means, each associated with a respective pair of the lamps and connected to one lead-in wire of each of the lamps of the associated pair, and a common terminal associated with all of the 2n lamps but directly connected to the other lead-in wire of one lamp of each pair. A respective normally open switch is coupled between the common terminal and a lead-in wire of the other lamp of each pair, so that the n normally open switches are coupled between the common circuit lead-in wires of associated pairs of the 2n lamps. Each of the switches is responsive to the flashing of the directly connected lamp of an associated pair so as to electrically connect the other lamp of the pair to the common terminal. In one specific example, ten lamps are selectively paired to be operated sequentially by firing pulses successively applied to five selective terminals together with a common terminal.

Abstract: An improved photoflash unit comprising a circuit board with lamp-firing circuitry thereon, a plurality (e.g., ten) of electrically activated photoflash lamps, and a reflector located between the lamps and circuitry. The lamp-firing circuitry includes at least one switch which is activated by radiant energy emitted from an adjacent photoflash lamp. The improvement comprises providing at least one longitudinal opening (slot) within a cavity portion of the reflector between the activating lamp and switch, and surrounding the opening with a transparent, non-conductive region to thereby assure consistent switch activation by substantially eliminating arcing between the reflector and circuitry.

Abstract: A photoflash unit comprising a linear array of flashlamps mounted on a printed circuit board disposed within the longitudinal channel of an elongated housing member having an enclosing cover panel of light-transmitting material. The lamp-firing circuitry includes a common circuit conductor run connected to one lead-in wire of each of the lamps. The housing member includes reflector cavities adjacent to the lamps, and a continuous coating of electrically conductive reflective material covers the surfaces of the channel and reflector cavities for providing both reflective surfaces for flashing lamps and, by virtue of a connection between the common run and conductive coating, a shield to reduce the likelihood of accidental flashing of lamps by electrostatic charges.

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, and the circuit strip extends beyond the cover panel to expose connecting terminals. The lamps have tubular envelopes and are positioned with their longitudinal axes substantially parallel to the printed circuit strip and arranged in substantially coaxial alignment. The housing member includes ledges within the channel for spacing the printed circuit strip from the rear wall, and the sidewalls of the channel have guide ribs for engaging notches in the circuit strip for facilitating assembly and location and avoiding longitudinal shifting of the strip.

Abstract: A disk-shaped flashlamp unit for use within an indexing means or mechanism associated with a camera. The unit includes several, e.g. ten, electrically-activated flashlamps radially disposed within the unit's plastic, light-transmitting housing. A pair of planar reflectors are utilized for each lamp to reflect the light therefrom through the housing. Light output can be further enhanced by utilization of two additional planar reflective members adjacent each lamp, the four members surrounding the side and bottom portions of the flashlamp's envelope to thereby direct light emitted from the flashlamp in a substantially singular direction through the peripheral region of the plastic housing. The invention's reflectors also assure prevention of sympathetic ignition.

Abstract: A photoflash unit comprising a linear array of flashlamps mounted on a printed circuit board 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 terminal at the remote end so as to reduce the red-eye photographic effect. The lamp-firing circuitry includes a pair of spaced-apart common circuit conductor runs respectively located on opposite halves of the printed circuit board and on opposite sides of a common surface. An interconnecting jumper, or crossover, between the common circuit runs is provided by means of a conductive staple secured to the circuit board.

Abstract: A photoflash unit which includes a printed circuit board and a plurality of electrically-activated flashlamps. Each lamp includes a pair of lead-in wires each of which includes a looped portion for being frictionally inserted within an opening in the board to secure the lamp thereto. The looped portions may also be utilized to effect contact with the board's lamp-firing circuitry or separate portions of the wires may be crimped, bent, etc. to provide said contact.

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: An electrically-activated photoflash lamp which includes a glass envelope, combustion-supporting (e.g. oxygen) atmosphere, a quantity of filamentary combustible material (e.g. zirconium), and an ignition means including a pair of spaced leads sealed within the envelope and a primer mass for igniting the combustible material. The primer mass includes a first quantity of substantially non-ignitable primer material having a second quantity of highly ignitable primer material located thereon. Use of the first primer material permits pulsing of the lamp in air prior to application of the second primer material to thereby assure uniform ignition voltages between lamps similarly treated. A circuit utilizing a plurality of the above lamps and a method for producing said lamps are also disclosed.

Abstract: A flash lamp array is disclosed having a plurality of flash lamps connected to sequencing circuitry on a circuit board. A plurality of solid-state thermally activated switches, having predetermined composition and physical characteristics and predetermined dimensions, are located externally of the lamps and affixed directly to one side of the circuit board. The sequencing circuitry includes printed circuit branches having a plurality of spaced-arm sections two of which overlay each of the switches and terminate proximate each of the switches. The exposed surface portion of the switches upon being irradiated by a flashed lamp converts to an electrically conductive state to insure a closed electrical circuit between the overlaying spaced-arm sections of the printed circuit.

Abstract: A photoflash lamp array of the FlipFlash type comprising a plurality of flash lamps, a reflector unit, a circuit board, and a flash indicator sheet. The reflector unit is provided with one or more indexing rim protrusions which extend into flash indicator openings in the circuit board for aligning the reflector unit to the circuit board.

Abstract: A flash lamp array is disclosed including a plurality of flash lamps and a two-sided circuit board having sequencing circuitry affixed to one side thereof and having the lamps connected thereto to fire individually and in sequence. The array comprises solid-state thermally activated switches located externally of the lamp and affixed to one side of the circuit board forming a part of the sequencing circuitry. Each of the switches is located in close proximity to one of the flash lamps to receive thermal energy emitted by the proximate flash lamp upon its being fired, and thereby changes from a high resistance or non-conductive state to a low resistance or conductive state. The switches comprise a uniform mixture of predetermined proportions of finely divided silver carbonate, finely divided silver oxide and finely divided hydrophobic silica. Switches prepared from this mixture are reliable and have no tendency to crack. The mixture is easy to work with being very free flowing.

Abstract: An improved circuit board comprising a substrate having electrical conductor runs resistant to the formation of electrically non-conductive localized areas carried thereon. Such a circuit board is particularly adapted to use with a flash lamp array having a plurality of flash lamps and sequencing electrical circuitry for sequentially flashing the lamps. The sequencing electrical circuitry is formed in part by the conductor runs. The conductor runs comprise an organic polymer binder for attachment of the conductor runs to the substrate and silver-coated vitreous bead-like particles with a triazole-silver water-insoluble reaction product comprising the surface of the bead-like particles. The triazole-silver reaction product prevents the formation of non-conductive localized areas in the conductor runs.

Abstract: The present invention relates to an electric flash device and, more particularly, to an improvement of the mechanical construction of a flashing member in the electric flash device.

Abstract: A photoflash lamp unit is described having a plurality of flash lamps fired individually and in sequence to include a plurality of switching devices each connected in the electrical circuit so as to interrupt the circuit path to a lamp that is flashed in response to the radiation emitted therefrom but still provide a circuit path to other unflashed lamps in the electrical circuit. In this manner, the desired firing sequence can be carried out although a particular flash lamp in the electrical circuit fails to fire because of defects other than a before-flash shorted condition and a more reliable switching arrangement is thereby provided.

Abstract: An elongated flash lamp assembly which is sequentially advanced through a camera to permit each of the lamps within the assembly to become aligned with the camera's fixed reflector. Several heat-responsive (e.g. fusible) covers are located on the assembly's housing to permit the above advancement only after each cover has become physically deformed by the heat from the respective flash lamp located adjacent thereto. A mechanism for advancing the assembly is also disclosed.

Abstract: A flashlamp unit having a plurality of flashlamps secured to a support on which an electrical circuit is printed. The flashlamps are connected to the circuit which includes break switches. The support with the electrical circuit and break switches has such a construction that the electrical conductors of the break switches and the circuit can be provided in the same operational step.

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. A plurality of reflectors respectively associated with the flashlamps are disposed between the lamps and 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 as to bridge a respective one of the apertures therein.

Abstract: The invention relates to a flash array provided with a number of high voltage combustion flash lamps which each cooperate with a single reflector sheet of an electrically conducting material. This reflector sheet is provided with holes; when a lamp is flashed a radiation-sensitive switching contact is affected via one of the holes.According to the invention the radiation-sensitive contacts open responsive to radiation. These contacts and the reflectors are connected to one another via a low-ohmic connection and whereby further a lamp, whose turn has not yet come, is short circuited. These measures result in the fact that the chance for premature ignition of a lamp is extremely small.