JP2002151279A - Lighting device for high pressure discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To aim at reduction of burden of lamp replacement at end of life of a lamp of a high pressure discharge lamp and at longer life ad cost reduction of the high pressure discharge lamp as a whole, as well as at facilitation of re-lighting just after turning off or the like. SOLUTION: The lighting device for the high pressure discharge lamp comprises a single lamp-lighting power source 2, a plurality of high pressure discharge lamps connected in parallel with the lamp-lighting power source 2, a starter 3 generating high voltage bringing forth dielectric breakdown between electrodes of high pressure discharge lamp at lighting start-up, and a selective circuit 4 keeping the past lighting record and deciding on which high pressure discharge lamp to be lit base on the record, and outputting a selective signal for making the starter fitted to the high pressure discharge lamp selected start it up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lighting device for a high-pressure discharge lamp, and more particularly to a lighting device for a high-pressure discharge lamp used for an image projection device such as a liquid crystal projector.

[0002]

2. Description of the Related Art Conventionally, a high-intensity discharge lamp such as a high-pressure mercury discharge lamp or a metal halide lamp has been used as a light source for an image projection device. Various technical improvements have been made to extend the life.

[0003]

In order to reduce the burden of replacing the lamp at the end of its life, a plurality of high-pressure discharge lamps are mounted on a high-pressure discharge lamp lighting device, and each high-pressure discharge lamp is lit for each lamp. A power supply is provided, and an appropriate lighting power supply is selected from the power supply so that one corresponding high-pressure discharge lamp can be turned on. By operating a lighting power supply provided in the high-pressure discharge lamp to light the high-pressure discharge lamp, the lighting device for the high-pressure discharge lamp may be extended in life as a whole.
However, in such a method, a plurality of lighting power supplies must be provided according to the number of high-pressure discharge lamps.

Instead of providing a lighting power supply for each high-pressure discharge lamp, a single lighting power supply is provided so that the high-pressure discharge lamp to be lit can be selected by an electric switch, and the high-pressure discharge lamps are sequentially switched. Although a high-intensity discharge lamp generally requires a high-voltage starter for starting, it requires a special switch and has a disadvantage of increasing the cost.

In addition, instead of the above electric switch,
Although a method of mechanically replacing the high-pressure discharge lamp is also conceivable, it requires a special lamp replacement mechanism, increases the cost, and has poor reliability.

[0006] As another problem, a high-pressure discharge lamp generally has a disadvantage that it is difficult to restart the lamp at a high temperature immediately after the lamp is turned off. No lighting device for a lamp has been found.

SUMMARY OF THE INVENTION In view of the above-mentioned various problems, an object of the present invention is to reduce the burden of replacing a high-pressure discharge lamp at the end of its life, to increase the life and cost of the high-pressure discharge lamp as a whole, Another object of the present invention is to provide a lighting device for a high-pressure discharge lamp which facilitates relighting immediately after the lamp is turned off.

[0008]

The present invention employs the following means in order to solve the above-mentioned problems.

A first means is a lighting device for a high pressure discharge lamp, comprising: a single lamp lighting power source; and a plurality of high pressure discharge lamps connected in parallel to the lamp lighting power source.
A starter is provided in each of the plurality of high-pressure discharge lamps and generates a high voltage that causes dielectric breakdown between electrodes of the high-pressure discharge lamp to be turned on at the time of starting the lighting. A high-pressure discharge lamp to be turned on based on the history; and a selection circuit for outputting a selection signal for starting up a starter provided in the determined high-pressure discharge lamp.

A second means is the first means, wherein the past lighting history is a light amount of a high pressure discharge lamp,
The selection circuit, when the amount of light of the high-pressure discharge lamp used is attenuated to a predetermined value, so as not to output a selection signal to a starter provided in the high-pressure discharge lamp at the next startup of the high-pressure discharge lamp. It is characterized by having done.

The third means is the first means, wherein the past lighting history is an elapsed time from the start of a starter provided to the high-pressure discharge lamp to be turned on to the restart thereof, and When the elapsed time is within a predetermined time, the circuit does not output a selection signal to the starter.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a basic configuration of a lighting device for a high-pressure discharge lamp according to the present embodiment. In FIG. 1, reference numeral 1 denotes a high-intensity discharge lamp such as a plurality of high-pressure mercury discharge lamps or metal halide lamps, each of which is connected in parallel to a single lamp lighting power supply to be described later, and reference numeral 2 denotes one of the high-pressure discharge lamps 1. A single lamp power supply provided for lighting, a starter (starter) 3 provided for each of the plurality of high-pressure discharge lamps 1 and generating a high voltage that causes dielectric breakdown between the electrodes of the high-pressure discharge lamp 1; 4
Is a selection circuit for outputting a selection signal for activating the starter 3 to the starter 3 of the high-pressure discharge lamp 1 to be turned on from among the plurality of high-pressure discharge lamps 1; When used as a light source device of the apparatus, an image projection optical system 6 for introducing the lamp light emitted from the high-pressure discharge lamp 1, and 6 is a DC power supply.

As shown in FIG. 1, in the lighting device for a high-pressure discharge lamp, all of the plurality of high-pressure discharge lamps 1 are connected in parallel to one lamp lighting power source 2. 2, for example 100 to 1000
Even if a voltage of about V (no-load open-circuit voltage) is applied to all the high-pressure discharge lamps 1 in common, none of the high-pressure discharge lamps 1 is lit only by this voltage. When a desired one high-pressure discharge lamp 1 is turned on, a no-load open-circuit voltage is applied from a lamp lighting power supply 2 and the starter 3 attached to the high-pressure discharge lamp 1 to be turned on is supplied to the starter 3. Is output from the selection circuit 4 for activating. When the selected starter 3 is started, for example, a high voltage of about 5 kV to 30 kV is applied to the high-pressure discharge lamp 1.
To cause a dielectric breakdown in a region between the electrodes of the high-pressure discharge lamp 1, whereby a discharge current starts to flow from the lamp lighting power supply 2, and lighting start is started. Further, the lamp light emitted from the turned on high-pressure discharge lamp 1 is introduced into the image projection optical system 5 and functions as a light source of the image projection device.

Here, the selection circuit 14 has a function of retaining the lighting history of the high-pressure discharge lamp 1 in the past. For example, although not shown, the light amount sensor detects the light amount of the lit high-pressure discharge lamp 1 and, when it is determined that the light amount is greatly attenuated, this light amount is attenuated at the next lighting of the high-pressure discharge lamp. The selection signal is not output to the starter 3 provided in the high-pressure discharge lamp 1 described above.

Generally, in a high pressure discharge lamp, the amount of radiation attenuates little by little due to adhesion to the arc tube due to evaporation of electrode constituent materials, cloudiness of the arc tube, etc. However, in an image projection device such as a liquid crystal projector, a viewer is uncomfortable. In particular, recent projector devices have a high demand for image clarity and are strongly required to always project brightly. On the other hand, even if the amount of radiation is attenuated, it is possible to forcibly turn off the high-pressure discharge lamp once and switch to another high-pressure discharge lamp during operation of the device, or to interrupt the image projection to the audience. And is not preferred.

According to the present invention, in order to improve such a situation, when the attenuation of the light amount reaches a certain amount, the information is recorded as a lighting history, and the high pressure discharge lamp which is immediately lit at that time is recorded. Instead of turning off the high pressure discharge lamp, the next time the high pressure discharge lamp is turned on, this lighting history is used to select a new high pressure discharge lamp to be turned on.

FIG. 2 is a diagram showing a specific configuration of the lighting device for a high-pressure discharge lamp shown in FIG. In the figure, 1
1 is a cathode of the high-pressure discharge lamp 1, 12 is a high-pressure discharge lamp 1
The anode 13 is a lamp envelope of the high-pressure discharge lamp 1.
Other configurations correspond to the configurations of the same reference numerals shown in FIG.

In this lighting device for a high-pressure discharge lamp, two discharge lamps 1 are connected in parallel to one lamp lighting power source 2,
This is an example in which a starter 3 is connected in series with the high-pressure discharge lamp 1 and a so-called series-type pulse starter for applying a high voltage between the cathode 11 and the anode 12 of the high-pressure discharge lamp 1 is attached. Here, the DC power supply 6 converts, for example, a DC voltage obtained by smoothing a voltage output from a diode bridge circuit or a voltage doubler rectifier circuit from an AC line having a commercial frequency by an active filter having a harmonic current suppressing function called a PFC. The power is supplied to the lamp lighting power supply 2.

The lamp lighting power supply 2 mainly includes a switch element (Q1) using a FET or the like, a diode (D1),
A step-down chopper including a choke coil (L1) and a smoothing capacitor (C1) is used to control the output to the high-pressure discharge lamp 1. The lamp voltage and the lamp current detected by the voltage detector V and the current detector I are input to a lamp control circuit, processed by the lamp control circuit, and supplied with appropriate lamp applied voltage, lamp current, and lamp power. As described above, the control signal is output from the lamp control circuit to the gate drive circuit provided for driving the switch element (Q1).

When the high pressure discharge lamp 1 in the upper part of the drawing is turned on, the starter 3 in the upper part of the drawing is selected by the selection circuit 4. As a result, the photocoupler light emitting diode (LED1) is energized, the photocoupler transistor (Q2) is turned on in response to the light emission signal from the photocoupler light emitting diode (LED1), and accordingly the transistor (Q3) is turned on. When the thyristor (S1) is turned on,
The capacitor (C2) is charged by the lamp lighting power supply 2 via the resistor (R1). The electric charge stored in the capacitor (C2) is rapidly discharged through the primary side of the transformer (T1), and generates a high voltage (Vs) in the secondary winding of the transformer (T1). This high voltage (Vs) is superimposed on the output voltage (Vo) of the lamp lighting power supply 2 and applied to the high-pressure discharge lamp 1, and the cathode 1 of the high-pressure discharge lamp 1 in the upper part of the drawing is shown.
A breakdown is caused between the anode 1 and the anode 12, and a discharge according to the output of the lamp lighting power supply 2 is started, so that the high-pressure discharge lamp 1 is turned on.

Conversely, when it is desired to turn on the high pressure discharge lamp 1 in the lower part of the figure, the starter 3 in the lower part of the figure is selected to be activated by the selection circuit 4, and the photocoupler light emitting diode (LED 2) of the starter 3 is energized. By doing so, the high-pressure discharge lamp 1 in the lower part of the figure can be turned on by the same operation as described above.

Here, the secondary winding of the transformer T1 of the starter 3 is inserted between the lamp cathode 11 and the negative terminal of the lamp lighting power supply 2, but this is connected to the lamp anode 12 and the lamp lighting. It may be inserted between the plus terminal of the power supply 2.

As for the polarity of the high voltage (Vs) applied between the cathode 11 and the anode 12 of the high-pressure discharge lamp 1 when the starter 3 operates, the polarity of the anode 12 may be higher than that of the cathode 11; Conversely, the cathode 11 may have a higher polarity than the anode 12.

FIG. 3 is a diagram showing another specific configuration of the lighting device for the high-pressure discharge lamp shown in FIG. In the figure, reference numeral 14 denotes a lamp envelope 13 of each high-pressure discharge lamp 1.
The other configurations correspond to the configurations of the same reference numerals shown in FIGS. 1 and 2, and the configurations and operations in the lamp lighting power supply 2 and the starter 3 are shown in FIG. The description is omitted because it is the same as that of FIG.

In this lighting device for a high pressure discharge lamp, two discharge lamps 11 are connected in parallel to one lamp lighting power supply 2, and a high voltage from a starter 3 is applied to each high pressure discharge lamp 1 via an external electrode 14. This is an example in which a so-called parallel type pulse starter for applying a voltage between the cathode 11 and the anode 12 of the high-pressure discharge lamp 1 is attached.

As for the starter 3, the transformer T1
The secondary winding is inserted between the cathode 11 of the high-pressure discharge lamp 1 and the negative terminal of the lamp lighting power source 2 in the high-pressure discharge lamp lighting device shown in FIG. , Cathode 11 of high pressure discharge lamp 1 and lamp lighting power supply 2
And the secondary winding of the transformer T1 is connected between the cathode 11 and the external electrode 14 of the high-pressure discharge lamp 1.

When the photocoupler light emitting diode (LED1) of the starter 3 is selected by the selection circuit 4 and turned on to turn on the high pressure discharge lamp 1 in the upper part of the figure,
External electrode 14 of lamp envelope 13 of high-pressure discharge lamp 1
A dielectric breakdown occurs between the nearby inner surface and the cathode 11, a discharge according to the output of the lamp lighting power supply 2 is started, and the high-pressure discharge lamp 1 is turned on.

Here, the secondary winding of the transformer T1 is
Although the description has been given of the case where the connection is made between the cathode 11 of the high-pressure discharge lamp 1 and the external electrode 14, the connection may be made between the anode 12 and the external electrode 14 of the high-pressure discharge lamp 1. Also,
Regarding the polarity of the high voltage applied between the external electrode 14 and the cathode 11 or the anode 13 when the starter 3 operates,
The external electrode 14 may have a higher polarity than the cathode 11 or the anode 14.
A lower polarity may be used.

Although FIGS. 2 and 3 show the case where the serial type and the parallel type starter are used, both types may be used in combination. Further, as the method of the starter 3, a case is described in which a pulse starter that generates a high-voltage pulse having a short time width, for example, about 10 ns to 100 μs as a full width at half maximum is used, but a so-called DC starter in which the voltage gradually increases is used. Alternatively, any of the pulse starter and the DC starter may be used for both the serial type and the parallel type starters. Further, a pulse starter and a DC starter may be used together.

FIGS. 4 and 5 show a part of the configuration of a lighting device for a high-pressure discharge lamp when a series type DC starter is used as the starter 3 and a parallel type DC starter is used as the starter 3, respectively. is there.

In the power supply device for a discharge lamp shown in FIG.
When the high pressure discharge lamp 1 is started to be turned on, the starter 3 is selected by a selection circuit 4 (not shown), and when the photocoupler light emitting diode (LED1) is energized, as a result, it is supplied from the lamp lighting power supply 2. The electric charge stored in the capacitor (C2) is transferred to the transformer (T
Discharge rapidly through the primary side of 1), and the transformer (T1)
, A high voltage (Vs) is generated in the secondary winding. This high voltage (Vs) is rectified by the diode D2 and stored in the capacitor (C3), and the DC high voltage (Vds) stored in the capacitor (C3) is applied to the high-pressure discharge lamp 1 and the cathode of the high-pressure discharge lamp 1 A dielectric breakdown occurs between the anode 11 and the anode 12, a discharge according to the output of the lamp lighting power supply 2 starts, and the high-pressure discharge lamp 1 is turned on.

In the discharge lamp power supply device shown in FIG. 5, when the high pressure discharge lamp 1 is started to be lit, the starter 3 is selected by the selection circuit 4 as described above.
As described in the operation of the starter 3 in FIG. 4, a high voltage (Vs) is applied to the secondary winding of the transformer (T1) by the diode D.
2 is rectified and stored in the capacitor (C3),
DC high voltage (Vds) stored in capacitor (C3)
Is applied to the external electrode 14 of the high-pressure discharge lamp 1, causing dielectric breakdown between the inner surface near the external electrode 14 and the cathode 11,
Subsequently, the discharge according to the output of the lamp lighting power supply 2 is started, and the high-pressure discharge lamp 1 is turned on.

FIGS. 6 and 7 show a serial type pulse starter 3 and a serial type DC starter 3, respectively.
FIG. 2 is a diagram illustrating a configuration of a lighting device for a high-pressure discharge lamp when the configuration is divided into a plurality of common circuits and individual circuits provided for each of the high-pressure discharge lamps 1.

In the power supply device for a discharge lamp shown in FIG. 6, reference numeral 31 denotes a common circuit which constitutes a part of a pulse starter provided in one of the lighting devices for a high pressure discharge lamp, and 32 denotes an individual circuit for each high pressure discharge lamp 1. It is an individual circuit that constitutes a part of the provided pulse starter, and the common circuit 31 and the individual circuit 32 can function as one pulse starter together. Other configurations correspond to the configurations of the same reference numerals shown in FIG.

When the high-pressure discharge lamp 1 in the upper part of the figure is turned on, the selection circuit 4 selects the activation of the individual circuit 32 of the pulse starter in the upper part of the figure. The common circuit 31 of the pulse starter operates in accordance with the operation of the pulse starter 32, and the processing result in the common circuit 31 is transmitted again to the individual circuit 32 in the upper part of the figure, processed, and applied to the secondary winding of the transformer (T1). A voltage (Vs) is generated.

Here, the specific configuration of the common circuit 31 and the individual circuit 32 of the pulse starter will be described with reference to the starter 3 shown in FIG. 2, for example. The energizing circuit of (LED1, LED2) is a part of the individual circuit 32 of each high-pressure discharge lamp 1, and the photocoupler transistor (Q2) is configured to be able to receive light from each photocoupler light emitting diode (LED1, LED2),
The configuration from the photocoupler transistor (Q2) to the conduction circuit of the transistor (Q3) is described as a common circuit 31.
The gate circuit of the thyristor (S1) is provided with a switch element that can be opened and closed in response to a command from the selection circuit 4, and the thyristor (S1) includes the switch element and the transformer (T
The configuration up to 1) can be configured by forming a part of the individual circuit 32.

In the lighting device for a high-pressure discharge lamp shown in FIG. 7, reference numeral 31 denotes a common circuit which constitutes a part of a DC starter provided in one of the lighting devices for a high-pressure discharge lamp, and reference numeral 32 denotes an individual circuit for each high-pressure discharge lamp 1. Circuit, which constitutes a part of the DC starter to be used.
2 can function as a single series DC starter. Other configurations correspond to the configurations of the same reference numerals shown in FIG.

When the high-pressure discharge lamp 1 in the upper part of the figure is turned on, the start of the individual circuit 32 of the DC starter in the upper part of the figure is selected by the selection circuit 4. 32, the common circuit 31 of the DC starter operates, and the processing result in the common circuit 31 is transmitted again to the individual circuit 32 in the upper part of the figure, processed, and the high voltage is applied to the secondary winding of the transformer (T1). (Vs) can be generated. This high voltage (Vs) is rectified by the diode D2, and the DC high voltage (Vds) applied to the high-pressure discharge lamp 1 is stored in the capacitor (C3).

Here, the common circuit 31 and the individual circuit 32 of the DC starter, for example, when the starter 3 shown in FIG. 4 is described, the photocoupler light emitting diodes (LED1, LE
The energizing circuit of D2) is a part of the individual circuit 32 of each high-pressure discharge lamp 1, and the photocoupler transistor (Q
2) Each photocoupler light emitting diode (LED1, LE
D2) so as to be able to receive light, the configuration from the photocoupler transistor (Q2) to the conducting circuit of the transistor (Q3) is defined as a common circuit 31, and the thyristor (S
A switch element that can be opened and closed by a command from the selection circuit 4 is provided in the gate circuit of 1), and the thyristor (S1) to the transformer (T1) and the diode D including this switch element are provided.
2, a configuration including D3, a resistor R2, and a capacitor C3 can be configured as a part of the individual circuit 32.

As shown in FIGS. 6 and 7, a circuit portion commonly used for the starter provided in each of the high-pressure discharge lamps 1 is constituted as one common circuit, and the remaining circuit portions are formed as the respective high-pressure discharge lamps 1. , The circuit configuration can be simplified and the number of circuit elements can be reduced, which is economical, as compared with a case where a starter having all functions is provided for each high-pressure discharge lamp 1.

FIG. 8 is a diagram showing a specific configuration of the plurality of high-pressure discharge lamps 1 and the image projection optical system 5 of the discharge lamp power supply device shown in FIG.

In the figure, reference numeral 7 denotes each high-pressure discharge lamp 1
An ellipsoidal mirror provided at an outer peripheral portion of the mirror for reflecting lamp light emitted from the high-pressure discharge lamp 1 and emitting the reflected light in a predetermined direction;
Is a mirror capable of receiving lamp light emitted from each ellipsoidal mirror 7 and reflecting the received lamp light and radiating it to the image projection optical system 5. Reference numeral 51 is provided in the image projection optical system 5, and is turned on. Each of the high-pressure discharge lamps 1 is a condenser lens that emits lamp light emitted in a different direction from a mirror 8 in a predetermined direction each time the lamp 1 is different. Other configurations correspond to the configurations of the same reference numerals shown in FIG.

As shown in the figure, in this discharge lamp power supply device, a plurality of high-pressure discharge lamps 1 are dispersedly arranged on the same radius around a mirror 8, and any one of the high-pressure discharge lamps 1 is selected and turned on. Even so, the lamp light can be emitted in a predetermined direction via the mirror 8 and the image projection optical system 5.

As an image projection device using the power supply device for a discharge lamp, it can be applied to a data projector such as a liquid crystal projector or a digital micromirror device projector.

In this image projection apparatus, when the brightness of the high-pressure discharge lamp which has been used so far decreases, for example, the image projection apparatus stores the detecting means for detecting the brightness and the detected information. It is determined whether to turn on a new high-pressure discharge lamp based on information stored in the storage means at the next lighting,
What is necessary is just to operate a selection circuit based on the determination result.

As another method for selectively lighting the high-pressure discharge lamp, the lighting order of the high-pressure discharge lamp is determined in advance, and each time the high-pressure discharge lamp is turned on, the selection circuit is operated in accordance with the determined order. Then, one high-pressure discharge lamp may be selected and turned on.

Further, instead of the method of lighting the high pressure discharge lamp in a predetermined lighting order, instead of lighting the high pressure discharge lamp in advance,
The next high-pressure discharge lamp may be selected at random and turned on.

In addition, by using the lighting device for a high-pressure discharge lamp, if it is necessary to restart the lamp immediately after the lamp is turned off, a low-temperature high-pressure discharge lamp different from the high-pressure discharge lamp used immediately before is selected. However, by controlling the starter of the high-pressure discharge lamp to operate, the problem of difficulty in restarting the high-pressure discharge lamp can be easily solved. In this case, immediately after the lamp is turned off, when the high-pressure discharge lamp that has been used immediately before is to be restarted, the starter is restarted because the high-pressure discharge lamp does not reach the start lighting state even if the starter provided therein is started. Sometimes.

Such a situation can occur not only when the high-pressure discharge lamp is turned on immediately after the lamp is turned off, but also when the high-pressure discharge lamp is difficult to be turned on for other reasons.

Therefore, in this lighting device for a high pressure discharge lamp, a selection signal is output from a selection circuit to a starter provided in the high pressure discharge lamp in order to light the high pressure discharge lamp.
As a result, the starter is started, but since the high-pressure discharge lamp does not reach the start lighting, the elapsed time until the start is restarted is recorded as lighting history information. The selection signal is not output to the starter, and the selection signal is output to a starter provided in the high-pressure discharge lamp to turn on another high-pressure discharge lamp.

[0051]

According to the first aspect of the present invention, a starter is provided for each of a plurality of high-pressure discharge lamps.
Since only a single lamp lighting power supply is required, the cost of the apparatus can be reduced, and a plurality of high-pressure discharge lamps can be switched and used based on the lighting history of the high-pressure discharge lamp. Can be reduced,
As a whole, the life of the high-pressure discharge lamp can be extended.

According to the second aspect of the present invention, the high-pressure discharge lamp to be lit next time can be selected from a plurality of high-pressure discharge lamps based on the amount of light of the high-pressure discharge lamp used. A high-pressure discharge lamp that can always emit a predetermined amount of light and has a long life can be realized.

According to the third aspect of the present invention, even if the high-pressure discharge lamp is difficult to light, for example, immediately after the lamp is turned off,
By detecting the elapsed time between the start and the restart of the starter, the high pressure discharge lamp can be easily switched to another high pressure discharge lamp and turned on, so that the start of the high pressure discharge lamp can be accelerated as a whole.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of a lighting device for a high-pressure discharge lamp according to an embodiment of the present invention.

FIG. 2 is a diagram showing a specific configuration of a lighting device for a high-pressure discharge lamp shown in FIG.

FIG. 3 is a diagram showing another specific configuration of the lighting device for a high-pressure discharge lamp shown in FIG. 1;

FIG. 4 is a diagram showing a part of a configuration of a lighting device for a high-pressure discharge lamp when a series DC starter is used as a starter.

FIG. 5 is a diagram showing a part of the configuration of a lighting device for a high-pressure discharge lamp when a parallel type DC starter is used as a starter.

FIG. 6 is a diagram showing a configuration of a lighting device for a high-pressure discharge lamp in a case where a series pulse starter is used by being divided into one common circuit and an individual circuit provided for each high-pressure discharge lamp.

FIG. 7 is a diagram illustrating a configuration of a lighting device for a high-pressure discharge lamp when a series DC starter is used by dividing it into one common circuit and an individual circuit provided for each high-pressure discharge lamp.

8 is a diagram showing a specific configuration of a plurality of high-pressure discharge lamps and an image projection optical system of the discharge lamp power supply device shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High-pressure discharge lamp 11 Cathode of high-pressure discharge lamp 1 12 Anode of high-pressure discharge lamp 1 13 Lamp enclosure of high-pressure discharge lamp 1 14 External electrode of high-pressure discharge lamp 1 Lamp power supply 3 Starter 31 Starter common circuit 32 Individual starter Circuit 4 Selection circuit 5 Image projection optical system 51 Condenser lens 6 DC power supply 7 Elliptical mirror 8 Mirror Q1 Switch element using FET or the like Q2 Photocoupler transistor Q3 Transistor D1, D2, D3 Diode L1 Choke coil C1 Smoothing capacitor C2, C3 Capacitor LED1, LED2 Photocoupler light emitting diode S1 Thyristor R1, R2 Resistance T1 Transformer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshikazu Suzuki 1194 Sado, Bessho-cho, Himeji-shi, Hyogo USHIO Electric Co., Ltd. F-term (reference) 3K083 AA07 AA24 AA85 AA91 BA02 BC12 BC33 BE05 CA25 CA32

Claims (3)

[Claims] 1. A single lamp lighting power supply, a plurality of high-pressure discharge lamps connected in parallel to the lamp lighting power supply, and a plurality of high-pressure discharge lamps provided in each of the plurality of high-pressure discharge lamps;
A starter that generates a high voltage that causes dielectric breakdown between the electrodes of the high-pressure discharge lamp to be turned on at the time of starting lighting, and a high-pressure discharge lamp to be turned on based on this lighting history while holding a past lighting history A lighting circuit for the high-pressure discharge lamp, comprising: a selection circuit for outputting a selection signal for starting the starter provided in the determined high-pressure discharge lamp. 2. The past lighting history is the amount of light of a high-pressure discharge lamp, and the selection circuit determines that the amount of light of the high-pressure discharge lamp being used attenuates to a predetermined value. The lighting device for a high-pressure discharge lamp according to claim 1, wherein a selection signal is not output to a starter provided in the high-pressure discharge lamp at the time of startup. 3. The past lighting history is the elapsed time from the start of the starter provided to the high pressure discharge lamp to be turned on until the restart, and the selection circuit determines that the elapsed time is within a predetermined time. 2. The lighting device for a high-pressure discharge lamp according to claim 1, wherein the selection signal is not output to the starter in the case of (1).