Toshiba Lighting & Technology Corporation

Kabushiki Kaisha Toshiba

Photoscience Japan Corporation

Mitsuhiro Matsuda

Keiichi Shimizu

Hiroshi Kubota

Takuro Hiramatsu

Masatoshi Kumagai

Naoko Iwai

Ichiro Yokozeki

Hajime Osaki

Katsusuke Uchino

Yuji Yamakoshi

Kenji Araki

Fumio Hirano

A discharge lamp includes a discharge tube containing electrodes, and base sections. The base sections have terminals for connecting to external power lines, and internal power lines for connecting the terminals to the electrodes within the discharge tube. Information generation devices that generates information to be output to outside are provided within the base sections. Superimposition circuits that superpose the information, generated by the information generation devices, on the internal power lines within the base sections are also provided within the base sections. The information generation devices include sensors and generate information based on output of the sensors. A receiving circuit extracts and receives the information, superposed on the internal power lines, from the external power lines connected to the internal power lines. Thus, information generated on the discharge lamp side can be transmitted to outside with a simple construction.

Discharge lamp and discharge lamp apparatus

A lighting circuit according to embodiments includes: a self-hold element connected in series to an AC power source that generates power for lighting an illumination load, together with the illumination load, the self-hold element being configured to control supply of the power provided by the AC power source to the illumination load by the self-hold element being turned on/off; a noise prevention circuit connected in parallel to the self-hold element; and a damping circuit configured to connect a damping resistance to the noise prevention circuit parallely only for a predetermined period from turning-on of the self-hold element, thereby preventing the self-hold element from being repeatedly turned on/off during a period in which the self-hold element is on under normal conditions, due to a transient during power supply.

Lighting circuit and illumination device

This invention suppresses the occurrence of interference in a very short period to prevent device destruction. An inverter circuit of this invention includes a crystal oscillator, which oscillates at a fixed frequency, a load-status detector, which receives a voltage and current to be applied to a load including an inductive or capacitive component and detects the status of the load, a voltage-controlled oscillator, which oscillates at a frequency corresponding to the load status detected by the load-status detector, and a switch, which selects the output of the crystal oscillator or the output of the voltage-controlled oscillator and supplies the selected output to the load. An electrodeless discharge lamp lighting device according to this invention uses an inverter circuit having the above structure.

Inverter having frequency changing function

Growing community of inventors

Yokohama, Japan

Mitsuhiro Matsuda