Device for operation of a high pressure discharge lamp and a projector device

• US 20050140311A1
• Filed: 12/16/2004
• Published: 06/30/2005
• Est. Priority Date: 12/25/2003
• Status: Active Grant

• Current Assignee: Ushio Denki Kabushiki Kaisha
• Original Assignee: Ushio Denki Kabushiki Kaisha
• Inventors: Arimoto, Tomoyoshi, Suzuki, Yoshikazu, Sugaja, Katumi
• Granted Patent: US 7,138,769 B2
• Time in Patent Office: Days
• US Class Current: 315/209.T
• CPC Class Codes: H01J 61/547 using an auxiliary electrode outside the vessel H01J61/544 takes precedence
• CPC Class Codes: H01J 61/86 with discharge additionally constricted by close spacing of electrodes, e.g. for optical projection
• CPC Class Codes: H05B 41/042 using semiconductor devices
• CPC Class Codes: H05B 41/19 for lamps having an auxiliary starting electrode
• CPC Class Codes: H05B 41/2881 Load circuits; Control thereof
• CPC Class Codes: H05B 41/2888 the bridge being commutated at low frequency, e.g. 1kHz
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
• CPC Class Codes: Y10S 315/05 Starting and operating circuit for fluorescent lamp

Abstract

A device for operating a discharge lamp of the alternating current operating type has a high pressure discharge lamp with a silica glass discharge vessel in which a pair of opposed electrodes are located and on which a trigger electrode is located, a feed device which supplies an alternating discharge current to the high pressure discharge lamp, the feed device having a starter circuit, an inverter circuit with at least two switching devices; a coil which is located downstream of the inverter circuit and is series-connected to the discharge lamp; and a control element which produces on/off driving in alternation with a dead time, and in which the inductance of the coil is at most 210 μH.

Claims

1. Device for operating a high pressure discharge lamp which comprises:

a high pressure discharge lamp having a silica glass discharge vessel, a pair of opposed electrodes located in the discharge vessel and a trigger electrode located outside of the discharge vessel; and

a feed device which supplies an alternating discharge current to the high pressure discharge lamp,

wherein the feed device comprises;

a starter circuit which produces a high voltage with respect to the trigger electrode when operation is started;

an inverter circuit which has at least two switching devices;

a coil which is located downstream of the inverter circuit and which is series-connected to the discharge lamp; and

a control element which subjects the switching devices to on and off driving in alternation, with a dead time, and

wherein the inductance of the coil is at most 210 μ

H.

6. Device for operation of the high pressure discharge lamp as claimed in claim 1, wherein the feed device subjects the discharge lamp to operating control with a rated operating frequency in the range of from 60 Hz to 1000 Hz, wherein the feed device is adapted to operate the discharge lamp intermittently only short time intervals with a frequency which is lower than the rated operating frequency and is in a range of from 5 Hz to 100 Hz.

2. Projector device which comprises:

a rotary filter having color regions of at least R(ed)G(reen)B(lue);

a rotary drive means for the rotary filter;

a space modulation element which receives light which has passed through the rotary filter; and

an operation device for operating a high pressure discharge lamp,

wherein the operation device has a high pressure discharge lamp with a silica glass discharge vessel in which a pair of opposed electrodes are located and on which a trigger electrode is located, and a feed device which supplies an alternating discharge current to the high pressure discharge lamp, said feed device comprising;

a starter circuit which produces a high voltage with respect to the trigger electrode when operation is started;

an inverter circuit which has at least two switching devices;

a coil which is located downstream of this inverter circuit, which is series-connected to the discharge lamp and which has an inductance of at most 210 μ

H; and

a control element which subjects the switching devices to on/off driving in alternation with a dead time, and

wherein the control element subjects the switching devices to on/off driving asynchronously to the rotary filter and the space modulation element.

3. Device for operating a high pressure discharge lamp which comprises the following:

a high pressure discharge lamp having a silica glass discharge vessel in which a pair of opposed electrodes are located; and

a feed device which supplies an alternating discharge current to the high pressure discharge lamp,

wherein the feed device comprises;

a starter circuit which applies a direct current high voltage to the electrodes when operation is started;

an inverter circuit which has at least two switching devices;

a coil which is located downstream of the inverter circuit and is series-connected to the discharge lamp; and

a control element which subjects the switching devices to on/off driving in alternation with a dead time, and

wherein the starter circuit comprises;

a capacitor which applies a direct current high voltage to the discharge lamp;

a charging circuit for the capacitor;

a diode for preventing a reverse current with respect to the high voltage direct discharge current of the capacitor and which is series-connected to the discharge lamp; and

a circuit which short circuits the diode to prevent a reverse current during rated operation, and

wherein the inductance of the coil is less at most 210 μ

H.

5. Device for operation of the high pressure discharge lamp as claimed in claim 3, wherein the feed device subjects the discharge lamp to operating control with a rated operating frequency in the range of from 60 Hz to 1000 Hz, wherein the feed device is adapted to operate the discharge lamp intermittently only short time intervals with a frequency which is lower than the rated operating frequency and is in a range of from 5 Hz to 100 Hz.

4. Projector device which comprises:

a rotary filter having color regions of at least R(ed)G(reen)B(lue);

a rotary drive means for the rotary filter;

a space modulation element which receives light which has passed through the rotary filter; and

an operation device for operating a high pressure discharge lamp,

wherein the operation device has a high pressure discharge lamp with a silica glass discharge vessel in which a pair of opposed electrodes are located, and a feed device which supplies an alternating discharge current to the high pressure discharge lamp, the feed device comprising;

a starter circuit which applies a direct current high voltage to the electrodes when operation is started;

an inverter circuit which has at least two switching devices;

a coil which is located downstream of this inverter circuit, which is series-connected to the discharge lamp, and which has an inductance of at most 210 μ

H; and

a control element which subjects the switching devices to on/off driving in alternation with a dead time, and

wherein the starter circuit comprises;

a capacitor which applies a high voltage direct discharge current to the discharge lamp;

a charging circuit for the capacitor;

a diode for preventing a reverse current with respect to the direct current of said capacitor and which is series-connected to the discharge lamp; and

a circuit which short circuits said diode to prevent a reverse current during rated operation, and

wherein the control element subjects the switching devices to on/off driving asynchronously to the rotary filter and to the space modulation element.