Triggerable ceramic gas tube voltage breakdown device

A hermetically sealed gas tube voltage breakdown device comprising

• a first gap electrode,
• a second gap electrode, said first and second gap electrodes being the only gap electrodes in said device,
• an electrode gap formed between said gap electrodes, said electrode gap being the only electrode gap in said device,
• an elongated ceramic insulating spacer disposed between said gap electrodes, said insulating spacer comprising two elongated tubular spacer halves, and
• a trigger electrode physically separated from and electrically insulated from both of said gap electrodes and adapted to receive a trigger voltage signal, said trigger electrode including conductive material disposed between said spacer halves,
• said spacer including a thin wall portion having a wall thickness in the range of from about 0.015 inch to about 0.030 inch.

An electrical circuit for controlling the light output of a photoflash lamp comprising means for extinguishing a photoflash in response to an electrical signal said extinguishing means comprising means for generating trigger voltage signals and comprising a hermetically sealed triggerable gas tube voltage breakdown device having

• a first gap electrode;
• a second gap electrode, said first and second gap electrodes being the only gap electrodes in said device,
• an electrode gap formed between said gap electrodes, said electrode gap being the only electrode gap in said device,
• an elongated ceramic insulating spacer disposed between said gap electrodes and enclosing said electrode gap and
• trigger electrode means, physically separated from and electrically insulated from both of said gap electrodes and adapted to receive said trigger voltage signals that are distinct from the voltage applied across said gap electrodes, for increasing the electrical field intensity in the region of said gap electrodes in response to said trigger voltage signals, said trigger electrode means being entirely exteriorly disposed about the outer periphery of said insulating spacer and being axially aligned along the length of said insulating spacer with said region of said electrode gap and being electrically insulated from said electrode gap by said insulating spacer,
• said spacer including means disposed about the region of said electrode gap for enabling the electrical field intensity in said region to be increased in response to the application of said trigger voltage signals to said trigger electrode, said enabling means comprising a thin wall portion having a wall thickness from about 0.015 inch to about 0.030 inch.

An electrical circuit for controlling the light output of a photoflash lamp comprising means for extinguishing a photoflash lamp in response to an electrical signal, said extinguishing means comprising means for generating trigger voltage signals and comprising a hermetically sealed gas tube voltage breakdown device having

• a first gap electrode,
• a second gap electrode, said first and second gap electrodes being the only gap electrodes in said device,
• an electrode gap formed between said gap electrodes, said electrode gap being the only electrode gap in said device,
• an elongated ceramic insulating spacer disposed between said gap electrodes, said insulating spacer comprising two elongated tubular spacer halves;
• and
• a trigger electrode physically separated from and electrically insulated from both of said gap electrodes and adapted to receive a trigger voltage signal, said trigger electrode including conductive material disposed between said spacer halves,
• said spacer including a thin wall portion having a wall thickness in the range of from about 0.015 inch to about 0.030 inch.