JP2009110918A - Lighting device for high-voltage discharge lamp and light source device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To equalize temperature distribution in a bulb in the AC-lighting of a high-voltage discharge lamp. <P>SOLUTION: A lighting device for a high-voltage discharge lamp carries out the AC-lighting of the high-voltage discharge lamp comprised of a light emitting tube provided with a bulb with a pair of electrodes for light emission which are arranged facing each other and a member attached to the light emitting tube. The member is arranged to be asymmetrical to the pair of electrodes and supposing an alternate current which has positive and negative symmetry is applied to the pair of electrodes, the temperature distribution between the pair of electrodes is made unequal due to the asymmetry in arrangement. The lighting device for the high-voltage discharge lamp is provided with an AC-power supplying means for supplying the alternate current with positive and negative asymmetry to the pair of electrodes. In regard to the alternate current with positive and negative asymmetry, an actual value of a current flowing from an electrode which is the low temperature side to an electrode which is the high temperature side when the alternate current which has positive and negative symmetry is applied is made to be greater than an actual value of the current which is of reverse polarity. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high pressure discharge lamp lighting device capable of obtaining a stable light output without shortening the life of a high pressure discharge lamp including a second reflecting mirror, and a light source device including the lighting device.

  Generally, as a light source of a light source device such as a projector, a discharge lamp including a light emitting tube and a main reflecting mirror that directs light emitted from the light emitting tube in a certain direction is widely used. In such a discharge lamp, in order to increase the light emission efficiency from the main reflecting mirror by effectively using the leakage light from the arc tube, the second reflecting mirror is placed at a position facing the main reflecting mirror across the bulb portion. Arrangement is performed (for example, patent document 1).

  However, if measures such as Patent Document 1 are taken, the radiation efficiency of light can surely be increased, but in the case where the second reflecting mirror is disposed so as to cover the periphery of the light emitting part of the bulb, A 2nd reflective mirror will inhibit the heat radiation of a valve | bulb part. As a result, the temperature rise of the bulb portion on the side where the second reflecting mirror including the electrode is arranged becomes remarkable, and the lamp is shortened by inducing electrode wear, bulb blackening, white turbidity, and bulb deformation. End of life.

As one means for solving this problem, a means is disclosed in which the heat capacity of the electrode on the second reflecting mirror side is made larger than the heat capacity of the electrode on the main reflecting mirror side (for example, Patent Document 2).
As another means, means for making the electrode axis supporting the electrode on the second reflector side thicker and / or longer than the electrode axis on the main reflector side, and sealing the second reflector side on the main reflector side Means thicker than the sealing part, means for coating the sealing part on the second reflecting mirror side with a heat radiation material having better thermal conductivity than the material of the sealing part, light emitting part of the bulb surrounded by the second reflecting mirror Means for making the thickness larger than the thickness of the light emitting portion of the bulb on the main reflector side, means for bringing the end of the electrode on the second reflector side into contact with the inner surface of the bulb, and the like are disclosed. In addition, a pair of electrode shafts that respectively support the pair of electrodes are provided, and the pair of electrode shafts are respectively provided with heat conducting portions at end portions connected to the pair of electrodes, and the second reflection of the pair of electrodes. Means for making the heat capacity of the heat conduction part on the mirror side larger than the heat capacity of the heat conduction part on the main reflector side is also disclosed.

Both of these means increase the heat capacity of the second reflecting mirror side and / or increase the heat dissipation performance than the main reflecting mirror side, thereby making the temperature distribution of the bulb uniform and the second reflecting mirror side. It is intended to solve the problems induced by the increase in valve temperature.
JP-A-8-31382 International Publication No. 2004/086453 Pamphlet

  However, all the means described in Patent Document 2 have different specifications on the side where the main reflecting mirror is attached and the side where the second reflecting mirror is attached with respect to the specifications of the arc tube or the bulb portion of the arc tube. That is, the material of the arc tube, the manufacturing process, and even the manufacturing jig must be different from one side of the arc tube. In this case, the number of management items increases in terms of material procurement, and the number of process management items increases in the manufacturing process, and the process may be complicated. In addition, each manufacturing jig has to be prepared for its own use, which adds extra cost.

  Furthermore, it is conceivable that the direction is mistakenly attached when the reflecting mirror and the second reflecting mirror are attached to the completed arc tube. If this lamp is shipped, it will be a very short-lived lamp, and even if a specification error is detected in the lamp manufacturing inspection process, the lamp will be lit several times. In this case, the lamp electrode is damaged more than usual. Therefore, the lamp cannot be used and must be discarded, so that the yield of lamp manufacturing is also deteriorated.

  The first aspect of the present invention comprises a light emitting tube having a bulb portion having a pair of light emitting electrodes arranged opposite to each other and a member attached to the light emitting tube, and the members are disposed asymmetrically with respect to the pair of electrodes. A high-pressure discharge lamp lighting device for alternating-current lighting a high-pressure discharge lamp in which the temperature distribution between the pair of electrodes becomes non-uniform due to the asymmetrical arrangement if a positive and negative symmetrical alternating current is applied to the pair of electrodes. AC power supply means for supplying positive and negative asymmetrical alternating current to the electrodes of the positive and negative asymmetrical alternating current flows from the electrode on the low temperature side toward the electrode on the high temperature side when the positive and negative symmetrical alternating current is applied. The current-time product of the current (hereinafter referred to as “first current”) is a current (hereinafter referred to as “the first current”) flowing from the electrode on the high temperature side to the electrode on the low temperature side (if positive and negative symmetrical alternating current is applied). 2 A high pressure discharge lamp lighting device is greater than the current-time product of the current "hereinafter).

  A second aspect of the present invention is a light emitting device comprising a valve portion having a pair of light emitting electrodes arranged opposite to each other and a seal portion including conductors connected to electrodes formed integrally with the valve portion at both ends of the valve portion. A main reflecting mirror that reflects light from the arc tube in one direction on one of the tube and the seal portion, and a second reflecting mirror that is smaller than the reflecting mirror on the other side of the seal portion and disposed in a direction facing the main reflecting mirror In the high pressure discharge lamp lighting device having AC power supply means for supplying AC current to the pair of electrodes for AC lighting of the high pressure discharge lamp consisting of: The current-time product of the current flowing from the reflecting mirror side electrode toward the second reflecting mirror side electrode (hereinafter referred to as “first current”) is changed from the second reflecting mirror side electrode to the main reflecting mirror side electrode. Current flowing in the direction (hereinafter referred to as “second A high pressure discharge lamp lighting device is greater than the current-time product of the current "hereinafter).

  Here, in the first and second aspects, the pair of electrodes are asymmetric electrodes having different heat capacities dedicated to each electrode, and if a positive / negative symmetric alternating current is applied to the asymmetric electrode, the temperature distribution between the asymmetric electrodes is The case where it becomes non-uniform | heterogenous due to the difference in the heat capacity of each electrode can also be assumed.

In the first or second aspect, the positive / negative asymmetrical alternating current is a rectangular wave so that the peak value of the first current is higher than the peak value of the second current.
Further, the positive / negative asymmetrical alternating current is a rectangular wave so that the time width of the first current is longer than the time width of the second current.
Furthermore, the positive / negative asymmetrical alternating current is a rectangular wave, the peak value of the first current is higher than the peak value of the second current, and the time width of the first current is larger than the time width of the second current. I made it longer.

  In the first or second aspect, the positive and negative asymmetrical alternating current is a triangular wave whose current value increases at a predetermined slope within a half cycle, and the slope of the first current is smaller than the slope of the second current. I did it.

In the first or second aspect, the first current is I1, the second current is I2, and the currents I1 and I2 at the lamp voltages V _A and V _B (V _A <V _B ) are turned on. When each current-time product is It1 _A , It2 _A , It1 _B , It2 _B , the structure satisfying It1 _B / It2 _B <It1 _A / It2 _A is satisfied.

  In the first or second aspect, a positive / negative asymmetrical alternating current may be intermittently inserted into the positive / negative symmetrical alternating current.

  A third aspect of the present invention is a light source device comprising a high pressure discharge lamp lighting device, a high pressure discharge lamp, a high pressure discharge lamp lighting device and a high pressure discharge lamp according to the first or second aspect.

  According to the present invention, the effective value of the lamp current flowing from the electrode on the main reflecting mirror side to the electrode on the second reflecting mirror side flows in the opposite direction from the electrode on the second reflecting mirror side to the electrode on the main reflecting mirror side. Since it is configured to be larger than the effective value of the lamp current, the number of electrons colliding with the electrode on the second reflecting mirror side becomes smaller than the number of electrons colliding with the electrode on the main reflecting mirror side. Therefore, the electrode temperature rise on the second reflector side is smaller than the electrode on the main reflector side, and the temperature rise of the bulb portion due to heat conduction and heat radiation from the electrode is also reduced. As a result, even if the heat radiation of the bulb is obstructed by the second reflecting mirror, it is avoided that the temperature rise of the bulb portion on the side where the second reflecting mirror including the electrode is disposed becomes significant, and the temperature of the bulb The distribution can be made uniform, and the life of the lamp can be prevented from being shortened due to electrode wear, blackening of the bulb, white turbidity, and bulb deformation.

  Further, the high-pressure discharge lamp to be lit in the present invention has the same specifications on the side where the main reflecting mirror is attached and the side where the second reflecting mirror is attached with respect to the specification of the bulb portion of the arc tube. There is no need to increase the number of management items, and the process can be simplified. Also, there is no need to prepare a dedicated jig for each production jig. Furthermore, when the main reflector and the second reflector are attached to the completed arc tube, it is possible to make the specification that does not require designation of the attachment direction, and the lamp manufacturing yield is not deteriorated. Contributes to cost reduction.

  FIG. 1 is a circuit configuration diagram of the present invention. 1 will be described below. The high pressure discharge lamp lighting device of the present invention includes a full-wave rectifier circuit 10, a step-down chopper circuit 20 that controls a DC voltage of the full-wave rectifier circuit 10 to a predetermined lamp power or lamp current by a PWM (pulse width modulation) control circuit, and a step-down chopper circuit 20 A full bridge circuit 40 for converting the DC output voltage of the chopper circuit 20 into an AC rectangular wave current and applying it to the lamp 60, an igniter circuit 50 for applying a high voltage pulse voltage to the lamp at the start of the lamp, and the step-down chopper circuit 20 And a control circuit 30 for controlling the full bridge circuit 40. In order to make the drawing easy to see, a full-wave rectification / capacitor input type circuit is shown as the rectifier circuit 10, but a booster circuit (power factor correction circuit) or the like is included as necessary.

  The step-down chopper circuit 20 includes a transistor 21, a diode 22, a choke coil 23, and a smoothing capacitor 24 that are PWM-controlled by a PWM control circuit 34. A DC voltage supplied from the full-wave rectifier circuit 10 is converted into predetermined lamp power or lamp. Controlled to convert to current. The full bridge circuit 40 is controlled by the bridge control circuit 45 so that the pair of transistors 41 and 44 and the pair of transistors 42 and 43 are alternately turned on / off at a predetermined frequency. As a result, an alternating current (basically a rectangular wave) is applied to the lamp 60. The lamp 60 is assumed to have a rated power of about 50 to 400 W. The value of the predetermined lamp power or lamp current and the predetermined frequency are determined by the central control unit 35 in the control circuit 30. Further, the constant lamp current control uses the detected lamp current by the resistor 33, and the constant lamp power control uses the detected lamp voltage by the resistors 31 and 32 multiplied by the detected lamp current as required in the central control unit 35. be able to.

Next, an embodiment of the present invention will be described in comparison with a conventional example.
Describing the conventional example again, in the conventional example, a rectangular wave lamp current IL shown in FIG. 4 is passed through the high pressure discharge lamp shown in FIG. 2 to light the high pressure discharge lamp. At this time, the effective value (current-time product) of the lamp current IL is the same in the lamp current I2 flowing in the opposite direction to the lamp current I1 flowing from the electrode on the main reflector 70 side toward the other electrode as shown in FIG. It has become.

  Here, in the case of a high pressure discharge lamp having a second reflecting mirror 80 as shown in FIG. 3, when the lamp is turned on with a rectangular wave lamp current shown in FIG. The temperature of the bulb part on the second reflecting mirror 80 side will rise from the bulb part on the main reflecting mirror 70 side.

  As shown in FIG. 9, the lamp 91 has an initial lighting time, and both the electrode 91 on the main reflecting mirror 70 side and the electrode 92 on the second reflecting mirror 80 side have protrusions at the electrode tips. Since the distribution is non-uniform, when the cumulative lighting time of the high-pressure discharge lamp is increased, the electrode 92 on the second reflecting mirror 80 side is significantly worn, and the protrusion at the tip of the electrode disappears as shown in FIG. As shown in FIG. 2, a plurality of fine protrusions appear at the electrode tip, resulting in a rough state.

  Tungsten scattered from the electrode 92 in the process where the protrusion at the tip of the electrode disappears or the tip of the electrode becomes rough adheres to the inner surface of the bulb. The temperature rise of the valve part on the mirror 80 side causes a more vicious circle. As a result, bulb blackening, white turbidity and bulb deformation leading to a short lamp life were induced.

  In contrast, in the embodiment of the present invention, the high-pressure discharge lamp shown in FIG. 3 provided with the second reflecting mirror 80 flows from the electrode 91 on the main reflecting mirror 70 side toward the electrode 92 on the second reflecting mirror 80 side. On the other hand, the lamp current I1 is made to be larger than the current-time product It2 of the lamp current I2 flowing from the electrode 92 on the second reflecting mirror 80 side to the electrode 91 on the main reflecting mirror 70 side. To control. When connecting the high pressure discharge lamp lighting device and the high pressure discharge lamp, it is assumed that the two output lines of the high pressure discharge lamp lighting device and the electrodes 91 and 92 are connected with a predetermined polarity.

<Lamp current control method 1>
Specifically, as shown in FIG. 5, the peak value of the lamp current I1 flowing from the electrode 91 on the main reflecting mirror 70 side to the electrode 92 on the second reflecting mirror 80 side is expressed as the electrode on the second reflecting mirror 80 side. The current time product It1 can be made larger than the current time product It2 by making it higher than the peak value of the lamp current I2 flowing from 92 to the electrode 91 on the main reflector 70 side.

<Lamp current control method 2>
In addition, as shown in FIG. 6, the time width T1 of the lamp current I1 flowing from the electrode 91 on the main reflecting mirror 70 side to the electrode 92 on the second reflecting mirror 80 side is determined from the electrode 92 on the second reflecting mirror 80 side. The current time product It1 can also be made larger than the current time product It2 by making it wider than the time width T2 of the lamp current I2 flowing toward the electrode 91 on the main reflector 70 side (T1> T2).

<Lamp current control method 3>
Further, as shown in FIG. 7, the lamp current control method 1 and the lamp current control method 2 may be combined. That is, the peak value of the lamp current I1 is made larger than the peak value of the lamp current I2, and the time width of the lamp current I1 is made wider than the time width of the lamp current I2, whereby the current-time product It1 is set to the current time. It can be made larger than the product It2.

<Lamp current control method 4>
Moreover, as shown in FIG. 8, it is good also as not performing continuously the method shown to the said lamp current control methods 1-3 but implementing intermittently.

<Lamp current control method 5>
Alternatively, the lamp current may be formed based on a so-called triangular wave whose current value increases in a half cycle as shown in FIG. This triangular wave is generally a waveform suitable for forming and maintaining a projection that is the starting point of an arc on the electrode, and is a lamp current waveform that is often employed in high pressure discharge lamp lighting devices as a flicker prevention measure.
In FIG. 15, when the half-cycle start current is Imin and the end current is Imax, the peak value of the lamp current I1 flowing from the electrode 91 on the main reflector 70 side toward the electrode 92 on the second reflector 80 side is shown. (Imax) is equal to the peak value (Imax) of the lamp current I2 flowing from the electrode 92 on the second reflecting mirror 80 side to the electrode 91 on the main reflecting mirror 70 side, and the slope of the increase in the current value of I2 (Imax-Imin) was made larger than the inclination of I1.

<Lamp current control method 6>
Further, as shown in FIG. 16, the method shown in the lamp current control method 5 may be executed intermittently instead of continuously.

  According to the lamp current control method 5 or 6, since it is not necessary to increase the output peak current of the step-down chopper circuit 20, the step-down chopper circuit 20 can be kept at a low loss, and the driving frequency of the full bridge circuit 40 is made constant. Therefore, it is possible to simplify the control configuration of the bridge control circuit 45, which makes it possible to make the entire circuit highly efficient and low cost.

  By the lamp current control methods 1 to 6, the current-time product of the lamp current I1 flowing from the electrode 91 on the main reflecting mirror 70 side to the electrode 92 on the second reflecting mirror 80 side is calculated as the electrode 92 on the second reflecting mirror 80 side. Thus, the current-time product of the lamp current I2 flowing toward the electrode 91 on the main reflector 70 side can be made larger, and the bulb temperature distribution of the high-pressure discharge lamp can be made uniform.

When the lamp current control methods 1 to 6 are summarized, the current-time product It1 of the lamp current I1 flowing from the electrode 91 on the main reflecting mirror 70 side toward the electrode 92 on the second reflecting mirror 80 side is expressed as the second reflecting mirror 80 side. As long as the current-time product It2 of the lamp current I2 flowing from the electrode 92 toward the electrode 91 on the main reflector 70 side can be made larger, the concept of the present invention can be applied to any lamp current waveform.
That is, as shown in FIG. 17, the area A (corresponding to It1) in the figure may be larger than the area B (corresponding to It2) in any waveform.

In the lamp current control methods 1 to 6, the strength of the tendency of “effective value I1 _rms > effective value I2 _rms ” (that is, bias) may be changed according to the state of the electrode surface. In the following description, the strength of the tendency of “effective value I1 _rms > effective value I2 _rms ” (that is, bias) is represented by α = I1 _rms / I2 _rms (where α> 1).
For example, when the protrusion on the electrode 91 is further grown and the protrusion on the surface of the electrode 92 is dissolved, the temperature distribution state (hereinafter, referred to as the temperature on the electrode 91 side is low and the temperature on the electrode 92 side is high). It is desirable to increase the bias α.
Conversely, when the protrusions on the surface of the electrode 91 are melted and the protrusions on the electrode 92 are somewhat grown, the temperature distribution state (hereinafter referred to as the temperature on the electrode 92 side is high and the temperature on the electrode 92 side is low). Therefore, it is desirable to reduce the bias α.

Needless to say, the same effect can be achieved by replacing “effective value I1 _rms ” and “effective value I2 _rms ” with “current time product It1” and “current time product It2”, respectively.

More specifically, in the case of state A, the lamp voltage decreases because the distance between the electrodes becomes short, and in the case of state B, the lamp voltage increases because the distance between the electrodes becomes long. Therefore, it is preferable to increase the bias α as the lamp voltage is lower, that is, as the degree of the state A is increased.
Accordingly, in the central control unit 35, when the detected lamp voltages are V _A and V _B (V _A <V _B ), and the effective values of the respective lamp currents are I1 _A , I2 _A , I1 _B and I2 _B In addition, I1 _B / I2 _B <I1 _A / I2 _A may be satisfied. In other words, the deviation α may be monotonously decreased as the lamp voltage increases.

Also in the above, the effective values “I1 _A ”, “I2 _A ”, “I1 _B ”, and “I2 _B ” are represented by current-time products “It1 _A ”, “It2 _A ”, “It1 _B ”, and “It2”, respectively. It goes without saying that the same effect can be achieved even if it is replaced with “ _B ”.

  Here, the difference between the current-time product determined by the effective value of the lamp current I1 for equalizing the bulb temperature distribution of the high-pressure discharge lamp and the current-time product determined by the effective value of the lamp current I2 is experimentally determined. Desirable. This is because when the high-pressure discharge lamp having the second reflecting mirror 80 shown in FIG. 3 is lit with the lamp current of the conventional example, the temperature distribution of the bulb portion on the main reflecting mirror 70 side and the bulb portion on the second reflecting mirror 80 side is inconsistent. There are many parameters that determine the degree of uniformity, and even if the present invention is used, the difference between the current-time product of the lamp current I1 and the current-time product of the lamp current I2 for making the temperature distribution in the bulb portion uniform is uniquely determined. This is because it is difficult to decide.

  These parameters vary widely, such as the power input to the bulb, the bulb size, shape, or the size, shape, location, or lamp air cooling conditions of the main reflector 70 and the second reflector 80. The difference in current-time product may be determined so that the temperature distribution of the valve portion becomes uniform while actually measuring the temperature of the valve portion.

<Design example 1>
In consideration of the above, the inventors designed the following high pressure discharge lamp lighting device as the most preferred embodiment of the present invention. The rated power of the lamp used is 170W. In any design example, it was confirmed that the generation of short-life lamps was reduced as compared with the case of conventional lighting.
A lamp having a lamp voltage of 70 V is lit with a rectangular wave current of 100 Hz, and the effective value of the rated lamp current is 2.43 A, and the lamp current I1 that flows from the main reflector side electrode toward the second reflector side electrode. Was increased by 10% to 2.67A, and the peak value of the lamp current I2 flowing from the second reflector side electrode toward the main reflector side electrode was reduced by 10% to 2.31A. That is, the effective value I1 _rms was set to 2.67A, and the effective value I2 _rms was set to 2.31A (in this case, the current-time product It1: It2 is also 2.67: 2.31).

<Design example 2>
In the same lamp as in Design Example 1, the lamp is lit with a rectangular wave current of 100 Hz, and the effective value of the rated lamp current is 2.43 A, from the electrode on the main reflector side toward the electrode on the second reflector side. The peak value of the lamp current that flows from the electrode on the second reflector side to the electrode on the main reflector side is increased to 5.5 milliseconds by increasing the time width by 10% while maintaining the peak value of the flowing lamp current at 2.43 A. However, the time width was reduced by 10% to be 4.5 msec. That is, It1: It2 = 1.1: 0.9.

<Application>
In the above embodiment, the high pressure discharge lamp lighting device having improved lamp life is shown. FIG. 12 shows a light source device as an application using the high pressure discharge lamp lighting device.
In FIG. 12, 100 is the high pressure discharge lamp lighting device of FIG. 1 described above, 70 is a main reflector to which the lamp is attached, 80 is a second reflector attached at a position facing the main reflector 70 across the bulb. A mirror 110 is a high pressure discharge lamp lighting device and a housing containing the lamp. In addition, the figure is a schematic illustration of the embodiment, and the dimensions, arrangement, and the like are not as illustrated. Then, a projector is configured by appropriately arranging a video system member or the like (not shown) in the housing.

<Notes>
The basic concept of the present invention can be applied not only to the temperature distribution by the main reflecting mirror and the second reflecting mirror but also to the elimination of the temperature distribution caused by other members and cooling methods. In other words, the method of the present invention is effective as a means for eliminating any inter-electrode temperature distribution that occurs when a normal positive / negative symmetrical AC lamp current is applied. That is, if a positive / negative symmetrical alternating current is applied, the current time product of the lamp current flowing from the low temperature side electrode to the high temperature side electrode is made larger than the current time product of the opposite polarity lamp current. This is the essence of the present invention.

  The present invention can also be applied to a case where the pair of electrodes are asymmetric electrodes having different heat capacities dedicated to each electrode, and the temperature distribution between the asymmetric electrodes becomes non-uniform due to the difference in the heat capacities of the electrodes. That is, the temperature distribution becomes non-uniform due to the position of the fan inside, the air cooling direction, processing other than the second reflecting mirror around the lamp (for example, winding a trigger wire around the arc tube only on one side, thereby increasing heat dissipation), etc. In this case, the present invention can also be applied to the case where each electrode is manufactured in a different shape or material, thereby causing a different heat capacity between the asymmetric electrodes, and a temperature difference may occur due to the heat capacity difference.

In addition, although the said Example was shown as the most suitable example of this invention, the following is noted in connection with it.
(1) In the present embodiment, the “rectangular wave” or “triangular wave” as the output current strictly includes a waveform that is not a complete rectangular wave or triangular wave. For example, a waveform in which a sine wave of one cycle or more is superimposed on a complete rectangular wave for the purpose other than flicker suppression, a waveform in which there is slight unevenness in the middle of a half cycle as shown in FIG. 14, or FIG. Any waveform that can be turned on is also included. Therefore, the lamp current during normal lighting is intended to include such a waveform.
(2) In the embodiment, the AC power supply circuit is configured by the rectifier circuit 10, the step-down chopper circuit 20, and the full bridge circuit 40. However, other configurations may be used as long as an AC rectangular wave can be supplied to the lamp. For example, if the input power source is a DC power source, the front stage of the full bridge circuit may be only a DC / DC converter. In addition, other types of circuits such as push-pull inverters may be used instead of the full bridge circuit as long as direct current can be converted into alternating current.
(3) If the control circuit 30 can perform the inversion control of the transistors 41 to 44 of the full bridge circuit 40 and the PWM control of the transistor 21 of the step-down chopper circuit 20, the configuration in the control circuit is limited to the illustrated one. Not.
(4) It can be understood that the same effect can be achieved by replacing “current time product” (It) in this specification with “current square time product” (I ² t).

It is a circuit block diagram which shows the discharge lamp lighting device of this invention. It is a figure which shows the conventional lamp | ramp. It is a figure which shows the lamp | ramp with a 2nd reflective mirror. It is a figure which shows the lamp current by the conventional lighting method. It is a figure which shows the lamp current by the lighting method of this invention. It is a figure which shows the lamp current by the lighting method of this invention. It is a figure which shows the lamp current by the lighting method of this invention. It is a figure which shows the lamp current by the lighting method of this invention. It is a figure which shows the electrode of an early high pressure discharge lamp. It is a figure which shows the electrode in the life of the lamp | ramp with which the temperature distribution of a bulb | bulb is nonuniform. It is a figure which shows the electrode in the life of the lamp | ramp with which the temperature distribution of a bulb | ball is non-uniform | heterogenous. It is a figure which shows the light source device of this invention. It is a figure explaining this invention. It is a figure explaining this invention. It is a figure which shows the lamp current by the lighting method of this invention. It is a figure which shows the lamp current by the lighting method of this invention. It is a figure explaining the basic concept of this invention.

Explanation of symbols

1: AC power supply 10: Full-wave rectifier circuit 11: Diode bridge 12: Capacitor 20: Step-down chopper circuit 21: Transistor 22: Diode 23: Choke coil 24: Capacitor 30: Control circuits 31, 32, 33: Resistor 34: PWM control Circuit 35: Central control unit 40: Full bridge circuit 41, 42, 43, 44: Transistor 45: Bridge control circuit 50: Igniter circuit 51: Igniter control circuit 60: High-pressure discharge lamp 70: Main reflector 80: Second reflector 91, 92: electrode 100: high pressure discharge lamp lighting device 110: projector housing

Claims (10)

A light emitting tube having a bulb portion having a pair of light emitting electrodes arranged opposite to each other and a member attached to the light emitting tube, and the members are asymmetrically arranged with respect to the pair of electrodes. A high-pressure discharge lamp lighting device for alternating-current lighting of a high-pressure discharge lamp in which the temperature distribution between the pair of electrodes becomes non-uniform due to the asymmetric arrangement if a positive and negative symmetrical alternating current is applied,
AC power supply means for supplying positive and negative asymmetrical AC current to the pair of electrodes,
With respect to the positive and negative asymmetrical alternating current, if a positive and negative symmetrical alternating current is applied, a current-time product of a current (hereinafter referred to as “first current”) flowing from the electrode on the low temperature side to the electrode on the high temperature side is A high pressure discharge lamp lighting device having a current-time product of a current (hereinafter referred to as “second current”) flowing from an electrode on a high temperature side toward an electrode on the low temperature side. An arc tube having a bulb portion having a pair of light-emitting electrodes disposed opposite to each other, and a seal portion including a conductor connected to the electrode formed integrally with the bulb portion at both ends of the bulb portion, one of the seal portions A main reflecting mirror that reflects light from the arc tube in one direction, and a second reflecting mirror that is smaller than the reflecting mirror on the other side of the seal portion and disposed in a direction facing the main reflecting mirror. In the high-pressure discharge lamp lighting device provided with alternating-current power supply means for supplying alternating current to the pair of electrodes in order to alternately light the high-pressure discharge lamp,
For the alternating current supplied by the alternating-current power supply means, a current-time product of a current (hereinafter referred to as “first current”) flowing from the main reflector side electrode toward the second reflector side electrode is A high pressure discharge lamp lighting device characterized in that the current time product of a current (hereinafter referred to as "second current") flowing from the second reflector side electrode toward the main reflector side electrode is larger. .   3. The high pressure discharge lamp lighting device according to claim 1, wherein the positive / negative asymmetrical alternating current is a rectangular wave, and a peak value of the first current is higher than a peak value of the second current. .   3. The high pressure discharge lamp lighting device according to claim 1, wherein the positive / negative asymmetrical alternating current is a rectangular wave, and the time width of the first current is longer than the time width of the second current. .   3. The high pressure discharge lamp lighting device according to claim 1, wherein the positive / negative asymmetrical alternating current is a rectangular wave, a peak value of the first current is higher than a peak value of the second current, and the first A high pressure discharge lamp lighting device in which a time width of one current is longer than a time width of the second current.   3. The high pressure discharge lamp lighting device according to claim 1, wherein the positive / negative asymmetrical alternating current is a triangular wave whose current value increases with a predetermined slope within a half cycle, and the slope of the first current is the second current. High pressure discharge lamp lighting device smaller than the slope of the. 3. The high pressure discharge lamp lighting device according to claim 1 or 2, wherein the first current is I1, the second current is I2, and the lamp voltages V _A and V _B during lighting (V _A <V _B ) are set. when the respective current-time product of the current I1 and I2 and _{It1 a, It2 a, It1 B} , It2 B, the high pressure discharge lamp lighting device that meets the _{It1 B / It2 B <It1 a} / It2 a.   The high pressure discharge lamp lighting device according to claim 1 or 2, wherein the pair of electrodes are asymmetric electrodes having different heat capacities dedicated to each electrode, and if a positive / negative symmetric alternating current is applied to the asymmetric electrode, A high-pressure discharge lamp lighting device for alternating-current lighting of a high-pressure discharge lamp having a non-uniform temperature distribution due to a difference in heat capacity of each electrode.   The high pressure discharge lamp lighting device according to claim 1 or 2, wherein the positive / negative asymmetrical alternating current is intermittently inserted into the positive / negative symmetrical alternating current.   3. A light source device comprising: the high pressure discharge lamp lighting device according to claim 1; the high pressure discharge lamp; the high pressure discharge lamp lighting device; and a housing that houses the high pressure discharge lamp.

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