Flash tube with insulator end cap

Claim 1

An injection-triggered flash tube comprising: an elongated, light-transmitting envelope which is hermetically sealed; a rare gas in said envelope; a pair of electrodes in said envelope, one disposed at each end thereof; a respective lead-in conductor sealed through each end of said envelope and connected to the Electrode thereat; and an end cap at each end of said envelope, each of said end caps having a shoulder portion comprising a substantially tubular piece of insulating material coaxially disposed about and secured to the exterior of a respective end of said envelope, and an exterior terminal portion comprising a substantially tubular metal conductor secured to and coaxially projecting from said insulating shoulder, the piece of insulating material from which said shoulder is formed further including a coaxially extending tubular portion of substantially smaller diameter than said shoulder and having an axial bore through which said respective lead-in conductor passes, said metal terminal portion containing a cylindrical cavity within which the extended tubular portion of said insulating material is fitted and secured, and said terminal portion having an axial bore aligned with the bore in the extended tubular portion of said insulating material and through which said respective lead-in conductor passes and is electrically secured to said metal terminal portion, whereby said terminal portion is electrically connected to the electrode disposed within said respective end of the envelope.