Abstract: A cold cathode fluorescent lamp (CCFL) comprises an inner fluorescent tube and an outer glass tube which is sheathed on the outside of said inner tube, characterized in that said inner fluorescent tube and said outer glass tube is separately disposed, and there is a space therebetween. Said CCFL further comprises electrodes sealed at the ends of said inner fluorescent tube and said outer glass tube. The CCFL of the present invention has a double-tube construction, as a result, the inner fluorescent tube is not so much affected by a change in the environmental temperature. Further, the inner fluorescent tube and the outer glass tube are separately disposed so that the end of the inner fluorescent tube and the end of the outer glass tube are not integrally joined, so that a rate of the breakage caused by the temperature difference between two ends is dramatically reduced.

Abstract: A stroboscopic discharge tube for use in photography is provided which comprises a light-transmitting tube having its opposite ends closed, a cathode and an anode disposed within said tube, and plasma producing gas, said cathode comprising a first electric conducting stem extending through one end of the tube into the interior of the tube and a cathodic annular ring made of emissive material affixed to the stem at least by means of welding, said anode comprising a second electric conducting stem extending through the other end of the tube into the tube interior and an anodic annular ring made of impurity gas absorbing material secured to the second stem, the diameters of the cathodic and anodic rings being such that the outer peripheries of the rings are closely adjacent to the inner wall of the tube so as to define a confined discharging region between the two rings. The discharge tube of the invention provides stable light.