Abstract: A fluorescent lamp can be configured to prevent a decrease in luminescent efficiency when located in a high temperature room. The fluorescent lamp can include a couple of stems each including an emitter electrode located opposite to each other at each end of a tube, a filler gas located in the tube, a damping material and a coolest portion connected to the tube via the stem and the damping material. The coolest portion can be configured with a first material that has a higher thermal conductivity than the conductivity of both the tube and the stems. The damping material can be configured with both the first material and a second material that has a lower conductivity than the conductivity of the first material. A content ratio of first material vs. second material can change along a length of the damping material. Thus, the coolest portion can maintain a favorable temperature and the fluorescent lamp can maintain a favorable luminescent efficiency even when in a sealed casing.

Abstract: A method for manufacturing a hot cathode fluorescent lamp can ensure or facilitate stable initial luminous intensity and provide improved product life characteristics even when the hot cathode fluorescent lamp employs a glass tube with an outer diameter of less than 7 mm?. One end of a glass tube can be sealed with a glass bead of a mount structure. The other opening end of the glass tube can be welded with an opening end of an exhaust pipe with bent portions of lead wires being sandwiched between the opening ends of the glass tube and the exhaust pipe. After evacuating a vacuum system that is constituted by the inner spaces of the glass tube and the exhausted pipe communicating with each other, the bent portions of the lead wires which extrude outside the vacuum system can be clamp-connected to power source lines extending from an external power source. The emitter of the filaments can be activated by the generated heat of the filament.

Abstract: A fluorescent lamp can be configured to prevent a decrease in luminescent efficiency when located in a high temperature room. The fluorescent lamp can include a couple of stems each including an emitter electrode located opposite to each other at each end of a tube, a filler gas located in the tube, a damping material and a coolest portion connected to the tube via the stem and the damping material. The coolest portion can be configured with a first material that has a higher thermal conductivity than the conductivity of both the tube and the stems. The damping material can be configured with both the first material and a second material that has a lower conductivity than the conductivity of the first material. A content ratio of first material vs. second material can change along a length of the damping material. Thus, the coolest portion can maintain a favorable temperature and the fluorescent lamp can maintain a favorable luminescent efficiency even when in a sealed casing.

Abstract: A method for manufacturing a hot cathode fluorescent lamp can ensure or facilitate stable initial luminous intensity and provide improved product life characteristics even when the hot cathode fluorescent lamp employs a glass tube with an outer diameter of less than 7 mm?. One end of a glass tube can be sealed with a glass bead of a mount structure. The other opening end of the glass tube can be welded with an opening end of an exhaust pipe with bent portions of lead wires being sandwiched between the opening ends of the glass tube and the exhaust pipe. After evacuating a vacuum system that is constituted by the inner spaces of the glass tube and the exhausted pipe communicating with each other, the bent portions of the lead wires which extrude outside the vacuum system can be clamp-connected to power source lines extending from an external power source. The emitter of the filaments can be activated by the generated heat of the filament.

Abstract: The invention provides an arc tube with improved chromaticity and start-up characteristics that does not contain mercury, and provides a vehicle headlamp equipped with a metal halide lamp that contains no mercury in the arc tube. Among other improvements, the evaporation of low melting point metal halides is promoted and the start-up characteristics of the arc tube are improved.