Matsushita Electric Industrial Co., Ltd.

Nobuhisa Yoshikawa

Shigeru Horii

Kazuhiko Ito

Kazutaka Koyama

Takeshi Saito

Koji Miyazaki

Masayoshi Gyoten

Masataka Ozawa

Takayuki Kamitani

Atsuo Waki

Kazushige Sugita

Tetsuya Tahara

The present invention relates to an inverter driven lamp arrangement. The arrangement provides for the sensing of both lamp voltage and current. The arrangement also provides for a large current during times of low voltage and a small current during times of high voltage. The sensing of lamp current is done by a current detector that is connected to a resonance circuit whose output is applied in signal form to a lamp start control circuit. The resonant circuit is a series connected resonant circuit composed of a choke coil and a first capacitor. This series connected arrangement is further connected in series with a second non-resonant capacitor. Also the arrangement includes circuitry to gradually reduce the frequency of the inverter just after the lamp starts.

An inverter driven lamp arrangement having a current detection circuitry

A fluorescent lamp starter which includes: a series circuit to be connected to a power source for supplying an AC voltage, including a ballast and a fluorescent lamp equipped with electrodes; a transistor having a collector and an emitter connected through a diode between the electrodes on an opposite side of the fluorescent lamp in which the power source is not connected; a control voltage supply means having a resistance means and a capacitor, which are operated by a voltage between the collector and the emitter of the transistor; and a transistor base control means for switching the transistor by a total voltage of a part of a voltage generated in the resistance means of the control voltage supply means and a voltage generated in the capacitor thereof.

Fluorescent lamp starter having a transistor base control means

In a discharge-lamp lighting apparatus for lighting a discharge lamp such as a metal halide lamp, there is provided a lighting control circuit which controls its output in a starting time of the discharge lamp in response to at least a length of the last off-time and an on-time after the start of discharging; and a power supplied to the discharge lamp is controlled in accordance with this output of the lighting control circuit.

Apparatus for controlling the power to a discharge-lamp

A high pressure discharge lamp apparatus comprises:

High pressure discharge lamp apparatus

In a high pressure discharge lamp apparatus comprising a discharge tube and a current limiting device connected in series, an over-current protecting semiconductor switching device such as a triac (TC) is further connected in series to said discharge tube,

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Sakai, Japan

Nobuhisa Yoshikawa