Mitsubishi Denki Kabushiki Kaisha

Osram-melco Ltd.

Minolta Camera Kabushiki Kaisha

Osram Gmbh

Takashi Osawa

Katsuo Murakami

Seishiro Mitsuhashi

Yujiro Kamano

Takeo Saikatsu

Yoshinori Anzai

Hiromi Adachi

Mitsuhiro Ikeda

Toshihiko Kobayashi

Masaomi Takeda

Koji Kokufu

Kazutoshi Ishikawa

Hiroshi Ito

Kenji Nakamura

Nobuo Ukita

Yasumasa Hanazaki

Takashi Noguchi

Teruyoshi Noda

Takahiro Konomoto

Hironori Nishio

At the end of life of a fluorescent lamp having a base to which a pin is press-fitted, it is an object to prevent the pin from dropping or slanting, etc. A fluorescent lamp includes a base having a base body and a pin press-fitted to a hole formed on the base body. A pin retaining force (a pin torque of the base) Fe after use by which the base body retains the pin is at least 0.08 Nm after the fluorescent lamp is burned for a rated life, and a rate Fe/Fi of an initial pin retaining force Fi by which the base body retains the pin before use of the fluorescent lamp and the pin retaining force Fe after use is at least 0.66.

Fluorescent lamp and base with press-fit hole

Fluorescent lamp and ferrule

The present invention provides a method of lighting a hot-cathode type low-pressure rare gas discharge lamp without flicker. The method has the steps of operating, as a hot cathode, at least one of electrodes provided at both ends of a glass valve in a stable discharge state, and emitting light from a fluorescent material with the ultraviolet rays generated by the discharge of low-pressure rare gas sealed in the glass valve, or directly with visible light. The hot cathode is heated at least during lighting. In the method, the temperature of the hot cathode relative to the lamp current flowing between the electrodes is set within a region to prevent flicker in the discharge lamp.

Method of flicker-free lighting hot-cathode low-pressure rare gas

An apparatus for lighting a discharge lamp is provided with an inverter circuit 3 for causing an input power supply 2 to generate the voltage required for a discharge lamp 1, a rectifying smoothing circuit 4 for rectifying and smoothing the output of the invertor circuit 3, a feedback control circuit 8 for computing the power required for the discharge lamp 1 so as to control the feedback control circuit 8 in the feedback mode, a polarity switching circuit 9 for switching the polarity of the rectified and smoothed output to apply the output to the discharge lamp 1 with a low-frequency square wave, and an ignitor 11 for superposing a high-voltage pulse on the discharge lamp 1 when the discharge lamp 1 is started. The apparatus therefor further includes an overcurrent control circuit 14 for detecting an overcurrent flowing into the discharge lamp 1 so as to make the polarity switching circuit 9 perform a high-frequency chopper operation together with a low-frequency operation for only an interval during which the overcurrent flows, so that the life of the discharge lamp is prolonged by suppressing the overcurrent flowing into the discharge lamp and preventing its electrodes from wearing.

Lighting apparatus for discharge lamp

A low-pressure rare gas discharge lamp wherein a light emitting gas composed substantially 100% of rare gases is sealed in a bulb and light emitted is from the gas by electric discharge. An isolation film for the light emitting gas from the bulb is provided at least on the inner surface portion of the bulb which portion surrounds a positive column. In another embodiment, a hot cathode type low-pressure rare gas discharging fluorescent lamp includes a glass bulb, a pair of electrodes including an electrode acting as a hot cathode at least in a stable discharging state, the paired electrodes being provided within the glass bulb, a fluorescent substance layer formed on the inner surface of the glass bulb, and a light emitting gas sealed in the interior of the glass bulb. The fluorescent substance layer is rendered luminous by radiation emitted from the light emitting gas. A partial pressure of the sealed, light emitting gas is not higher than 5 Torr, and the light emitting gas includes at least krypton.

Low-pressure rare gas discharge lamp and method for lighting same

A green-light-emitting rare gas discharge lamp includes a glass tube filled with at least one selected from the group consisting of xenon, neon, helium, argon and krypton as a rare gas capable of emitting vacuum ultraviolet rays of a wavelength of not more than 200 nm, and includes on an inner surface of the glass tube a layer of a green-light-emitting phosphor having terbium-activated yttrium silicate, whereby it is intended to obtain enhanced performance as a green-light-emitting light source and to put the discharge lamp to practical use as a green-light-emitting light source for office automation equipment, for instance.

Green-light-emitting rare gas discharge lamp

Hot-cathode type low-pressure rare gas discharge lamp

A brake lamp apparatus causes a neon discharge lamp to light up instantly even when the vehicle key is not inserted into the key hole of the vehicle e.g., when the vehicle is being parked. A neon discharge lamp utilized in the apparatus is pre-heated but cathodes thereof to instantly light up in hot cathode discharge mode upon depression of a brake pedal when a generator drivingly connected with an engine is operating, whereas the hot cathodes of the lamp are not pre-heated but the lamp can still light up instantly in cold cathode discharge mode upon depression of the brake pedal when the generator is operating. Even if the filament coils of the lamp become cut off suddenly while the vehicle is running, the lamp can still light up, being shifted to in cold cathode discharge method, thereby overcoming a drawback that the brake lamp goes off suddenly due to a filament cut-off during running on a road.

On-vehicle brake lamp apparatus

Hot-cathode discharge fluorescent lamps filled with low pressure rare gas being discharge fluorescent lamps filled with low pressure rare gas with a tube diameter of 16 mm or less provided with a pair of electrodes on both ends of a glass tube which operate as a hot-cathode in a stable discharge condition, having a fluorescent material layer on the inside surface of the bulb, filled with a luminous gas therein, and which is illuminated with irradiation from discharge in the luminous gas, in which at least one gas of He, Ne, Ar, and Kr are filled in addition to Xe as the luminous gas in an amount that the percentage of additional gas volume to total gas volume exceeds 50%.

Hot-cathode discharge fluorescent lamp filled with low pressure rare gas

Growing community of inventors

Kanagawa, Japan

Takashi Osawa