Abstract: For a signal device comprising a plurality of percussively ignitable flashlamps mounted on a support member and arranged in an array with respectively associated preenergized striker springs, a selective actuating mechanism for sequentially releasing the striker springs to fire respective flashlamps in response to successive hand actuated indexing. The selective actuating mechanism comprises a spring-loaded ratchet bar retained in a longitudinal channel in the support member in combination with a slidable member which is also retained in the channel in engageable contact with the ratchet bar. The lamps and striker springs are mounted in a row parallel to the channel with the strikers projecting beyond the periphery of the channel. The slidable member, which may comprise a folded flat spring having a first tang for engaging the ratchet bar and a second tang for engaging a surface of the channel, has a trip wire projection which is aligned with the projecting portions of the strikers.

Abstract: A signal device comprising a partially transparent package containing a plurality of percussively-ignitable flashlamps arranged in an array with respectively associated preenergized striker springs, and a movable member for sequentially releasing the striker springs to fire respective flashlamps in response to successive indexing. The device is adapted to be hand held and the movable member is adapted to be actuated and indexed directly by hand.

Abstract: A photoflash lamp having a glass envelope with an inner layer or coating of a material selected to have a low thermal conductivity and diffusivity for minimizing heat losses during the collision of molten droplets of combustible metal with the inner wall of the envelope during flashing. In this manner, radiative energy losses resulting from the droplet-wall collisions are minimized and light output is improved.