Toshiba Lighting & Technology Corporation

Toshiba Lightec Kabushiki Kaisha

Naoki Tsutsui

Ryuji Tsuchiya

Takao Mizukami

Yuji Wagatsuma

Yoshinori Sato

Kiyoshi Nishimura

Masami Takagi

Ariyoshi Ishizaki

Masuo Shibuya

Kunio Yuasa

Miho Saito

Shinji Mochimaru

A dual tube type fluorescent lamp including a luminescence tube. The luminescence tube has a long and slender airtight glass bulb with a nonlinear form part, a pair of electrodes and a phosphor layer formed on the inside surface of the glass bulb. A gap is formed between the circumference of the luminescence tube and an outside glass tube. The luminescence tube encloses an electric discharge medium coating mercury and a rare gas. An inorganic substance layer is formed at least at the nonlinear form part either on the outer surface of the luminescence tube, on the inner surface of the outside glass tube, or both. The inorganic substance layer has a softening point higher than the softening point of the glass.

Dual tube fluorescent lamp and light device

A lighting device controls power to a discharge lamp according to the temperature detected by a lamp sensor, which detects temperature around the discharge lamp. The discharge lamp has an arc tube and an outer bulb between which an airtight space is defined. Therefore, the lamp can be actuated without reduction in luminosity even at low temperatures. Also, the lamp luminosity rises quickly.

Lighting device and display equipment

A low-pressure mercury vapor-filled discharge lamp has a glass arc tube and a glass outer tube disposed coaxially with the arc tube forming a space therebetween. A gas is disposed in the space. The arc tube contains a gas and is coated with a phosphor. A first seal hermetically seals the inner tube. A second seal seals the inner tube to the outer tube. The inner tube further contains a pair of cathodes coupled to Dumet wires extending from the interior of the inner tube to the outside of the lamp structure. The pressure in the space is set at not more than 1 Pa, which is nearly high vacuum. The longer the radial dimension of the space, the greater the heat retaining capacity and the better the temperature characteristics which can be obtained. However, by setting the pressure of the space at 1 Pa or less, the optimum heat retaining capacity can be obtained while reducing the diameter of the low-pressure mercury vapor filled discharge lamp 1.

Low-pressure mercury vapor-filled discharge lamp, luminaire and display

Discharge lamp

Growing community of inventors

Yokosuka, Japan

Naoki Tsutsui