H05B41/24

Gas discharge device and flat light source using the same, and driving method therefor

A gas discharge device includes a thin glass tube filled with a discharge gas; a pair of first and second long electrodes extending toward either side along a longitudinal direction with a discharge gap interposed therebetween are provided outside of a back side flat surface of a thin glass tube; and a ultraviolet phosphor layer formed on an inner surface at the back side flat surface, the thin glass tube filled with a discharge gas having a front side flat surface and the back side flat surface facing each other on a transverse section, wherein, starting with trigger discharge that is initially generated in the discharge gap as a result of a voltage increase when a voltage with a sine waveform or an inclined waveform is applied between both electrodes, the discharge gradually extends so as to move in the longitudinal direction of the electrodes. Ultraviolet light having high luminous efficiency and emission intensity is obtained from a front side surface of the thin glass tube by driving the device with a sine-wave AC voltage.

Discharge lamp driving device, projector, and discharge lamp driving method
09930305 · 2018-03-27 · ·

A discharge lamp driving device includes a discharge lamp driving unit configured to supply a driving current to a discharge lamp, and a control unit configured to control the discharge lamp driving unit. The discharge lamp driving device is configured to provide a first hybrid period and a second hybrid period each alternately including a first AC period in which an AC current is supplied and a first DC period in which a DC current with a first polarity is supplied. The control unit, in the first hybrid period, is configured to change a ratio of length of the first DC period to length of the first AC period to be increased, and in the second hybrid period, is configured to change a ratio of the length of the first AC period to the length of the first DC period to be increased.

Discharge lamp driving device, projector, and discharge lamp driving method
09930305 · 2018-03-27 · ·

A discharge lamp driving device includes a discharge lamp driving unit configured to supply a driving current to a discharge lamp, and a control unit configured to control the discharge lamp driving unit. The discharge lamp driving device is configured to provide a first hybrid period and a second hybrid period each alternately including a first AC period in which an AC current is supplied and a first DC period in which a DC current with a first polarity is supplied. The control unit, in the first hybrid period, is configured to change a ratio of length of the first DC period to length of the first AC period to be increased, and in the second hybrid period, is configured to change a ratio of the length of the first AC period to the length of the first DC period to be increased.

Common mode noise suppression of switchmode power converters by capacitive shield with damping network

A connected light node (CLN) induction light ballast module for powering an induction lamp includes a printed circuit board having components mounted thereon and an earth ground region electrically isolated from a PCB ground region. A heat sink is disposed on a lower layer of the printed circuit board and electrically connected to the earth ground region, wherein a parasitic capacitance occurs between the printed circuit board ground region and the heat sink. A capacitive shield sandwiched by a lower insulating pad and an upper insulating pad is electrically isolated from the heat sink supporting the shield. A damping network electrically connects the capacitive shield to the PCB ground region. Switch-mode power converters are mounted above the upper insulating pad and the shield. The damping network suppresses noise by a parasitic capacitance between the PCB ground region and the heat sink during high frequency power converter operation.

Common mode noise suppression of switchmode power converters by capacitive shield with damping network

A connected light node (CLN) induction light ballast module for powering an induction lamp includes a printed circuit board having components mounted thereon and an earth ground region electrically isolated from a PCB ground region. A heat sink is disposed on a lower layer of the printed circuit board and electrically connected to the earth ground region, wherein a parasitic capacitance occurs between the printed circuit board ground region and the heat sink. A capacitive shield sandwiched by a lower insulating pad and an upper insulating pad is electrically isolated from the heat sink supporting the shield. A damping network electrically connects the capacitive shield to the PCB ground region. Switch-mode power converters are mounted above the upper insulating pad and the shield. The damping network suppresses noise by a parasitic capacitance between the PCB ground region and the heat sink during high frequency power converter operation.

Discharge lamp driving device, projector, and discharge lamp driving method
09897902 · 2018-02-20 · ·

A discharge lamp driving device includes a discharge lamp driving section configured to supply a driving current to a discharge lamp including a first electrode and a second electrode and a control section configured to control the discharge lamp driving section. The control section is configured to repeat a unit period. The unit period includes a direct current period including a first direct current period in which a direct current having a first polarity is supplied to the discharge lamp and a second direct current period in which a direct current having a second polarity is supplied to the discharge lamp, and an alternating current period provided between the first direct current period and the second direct current period, an alternating current being supplied to the discharge lamp in the alternating current period. The control section is configured to temporally change length of the direct current period.

Discharge lamp driving device, projector, and discharge lamp driving method
09897902 · 2018-02-20 · ·

A discharge lamp driving device includes a discharge lamp driving section configured to supply a driving current to a discharge lamp including a first electrode and a second electrode and a control section configured to control the discharge lamp driving section. The control section is configured to repeat a unit period. The unit period includes a direct current period including a first direct current period in which a direct current having a first polarity is supplied to the discharge lamp and a second direct current period in which a direct current having a second polarity is supplied to the discharge lamp, and an alternating current period provided between the first direct current period and the second direct current period, an alternating current being supplied to the discharge lamp in the alternating current period. The control section is configured to temporally change length of the direct current period.

LED tube lamp

An LED tube lamp includes a tube, two end caps, a power supply, and an LED light strip. The tube includes two rear end regions, two transition regions, and a main body region. The end caps are respectively connected to the rear end regions. The power supply is in one or both of the end caps. The LED light strip including one or more LED light sources is in the tube. The LED light sources are electrically connected to the power supply via the LED light strip. The end cap includes a lateral wall, an end wall, and at least one opening for heat dissipation and/or pressure releasing. The at least one opening penetrates through the end cap with a light sensor inside the end cap collimating with the opening.

Electrodeless high intensity discharge lamp with wave-launcher

Electrodeless high intensity discharge (HID) lamps have the promise of higher reliability and higher efficiency than traditional electroded high intensity discharge lamps. However, most electrodeless HIDs operate in the frequency range of around 400 MHz or higher resulting in expensive, inefficient RF drivers that reduce the overall efficacy of the lamp. Operating the lamp at lower frequencies results in substantial increase in the physical dimensions of the resonators used in traditional electrodeless HIDs. In this invention a novel wave-launcher technology is used allow the lamp housing's operating frequency to be independent of the physical dimensions of the lamp housing. This provides an avenue to increase the conversion efficiency of the RF driver and the efficacy of the lamp system.

Electrodeless high intensity discharge lamp with wave-launcher

Electrodeless high intensity discharge (HID) lamps have the promise of higher reliability and higher efficiency than traditional electroded high intensity discharge lamps. However, most electrodeless HIDs operate in the frequency range of around 400 MHz or higher resulting in expensive, inefficient RF drivers that reduce the overall efficacy of the lamp. Operating the lamp at lower frequencies results in substantial increase in the physical dimensions of the resonators used in traditional electrodeless HIDs. In this invention a novel wave-launcher technology is used allow the lamp housing's operating frequency to be independent of the physical dimensions of the lamp housing. This provides an avenue to increase the conversion efficiency of the RF driver and the efficacy of the lamp system.