JP2017156660A - Light source device and image projection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source device and an image projection device capable of determining necessity of replacement of a light source with a simple configuration.SOLUTION: The light source device includes: a light source; a light source drive part that drives the light source; a storage part that stores a drive voltage or a drive current to the light source which is acquired via the light source drive part; and a determination part that determines the necessity of replacement of the light source by comparing a present value and a value stored in the storage part with respect to the drive voltage or the drive current of the light source.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light source device and an image projection device, and is particularly suitable for an image projection device using a high-pressure discharge lamp.

  In recent years, an ultra-high pressure mercury lamp, which is a high-pressure discharge lamp, has been mainly used as a light source of an image projection apparatus. Such an ultra-high pressure mercury lamp can obtain light with high luminous efficiency, but the illuminance decreases with use time. Therefore, it is preferable to replace the ultra-high pressure mercury lamp (lamp unit) at an appropriate timing.

  In the conventional liquid crystal projector, the lamp usage time is stored, and when the user replaces the lamp unit, the user himself has to perform an operation of resetting the lamp usage time. If this reset operation is not performed, the liquid crystal projector cannot determine whether or not the lamp unit has been replaced. For this reason, for example, when a lamp unit is replaced before a predetermined usage time without performing a reset operation, a notification prompting replacement of a newly installed lamp unit is issued even though the lamp unit can be illuminated with sufficient illuminance. There was a fear.

  As a technique for solving such a problem, techniques described in Patent Documents 1 and 2 are known. Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique in which the lamp usage time is written in a storage unit provided in the lamp unit, and the lamp usage time is communicated from the lamp unit to the image projection apparatus. As a result, it is possible to determine whether the lamp unit is new, that is, whether the lamp unit has been replaced, by reading the usage time from the storage means provided in the lamp unit.

  Patent Document 2 discloses a technique in which a switch for detecting attachment / detachment of a lamp is provided in an image projection apparatus, and lamp replacement is detected by ON / OFF of the switch.

JP 2003-330112 A JP 2009-192711 A

  However, the above-described conventional technique needs to add a storage unit to the lamp unit or add a switch to the image projection apparatus, which may complicate the configuration of the apparatus.

  An object of the present invention is to provide a light source device and an image projection device that can determine whether or not a light source is replaced with a simpler configuration.

  In order to achieve the above object, a light source device according to the present invention stores a light source, a light source drive unit that drives the light source, and a drive voltage or drive current of the light source obtained through the light source drive unit. And a determination unit that determines whether or not the light source is replaced by comparing a current value and a value stored in the storage unit with respect to a driving voltage or a driving current of the light source. .

  Moreover, the image projection apparatus which concerns on this invention is provided with the said light source device.

  According to the present invention, it is possible to determine whether or not the light source is replaced with a simpler configuration.

It is a figure which shows the operation | movement during the lighting of the light source in the 1st Embodiment of this invention. It is a figure which shows the comparison operation regarding the light source lighting of the last time and this time in 1st Embodiment. It is a figure which shows the structure of the light source device in embodiment of this invention. It is a figure which shows transition of the lamp voltage by the lamp lighting time in embodiment of this invention. It is a figure which shows the operation | movement during the lighting of the light source in 2nd Embodiment. It is a figure which shows the comparison operation regarding the light source lighting of the last time and this time in 2nd Embodiment. It is a figure which shows the message regarding lamp replacement. It is a figure which shows the structure of the image projection apparatus carrying the light source device which concerns on embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<< First Embodiment >>
(Image projection device)
FIG. 8 is a diagram illustrating a configuration of an image projection apparatus (projection-type image display apparatus) 100 including a light source device described later according to an embodiment of the present invention. The image projection apparatus 100 has a function of displaying an image, and projects an original image formed on the reflective liquid crystal display element 50 onto a screen 500 that is a projection surface.

  The image projection apparatus 100 includes a housing 110, a high-pressure discharge lamp (lamp) 10 as a light source, an illumination optical system 20, a color separation / synthesis optical system (color separation / synthesis system) 30, and a projection optical system (projection lens optics). System) 40 and a liquid crystal display element 50. Furthermore, a storage unit (memory) 60, a control unit 70, and a calculation unit 80 are included.

  Around the lamp 10 having a function of generating light, a lamp cooling FAN (cooling fan) 95 for sending cooling air as a blower and the air from the cooling fan 95 to the lamp 10 through the opening. An air guide path 90 for guiding is arranged. The rotation speed of the cooling fan 95 is controlled by FAN control means (fan control means) 98.

  The illumination optical system 20 has a function of transmitting light from the lamp 10 to the color separation / synthesis optical system 30. The illumination optical system 20 includes cylinder arrays 21 and 22, an ultraviolet absorption filter 23, a polarization conversion element 24, a front compressor 25, a reflection mirror 26, a condenser lens 27, and a rear compressor 28.

  The cylinder arrays 21 and 22 are composites of photosensitive elements incorporated in a camera, a detector, a scanning device, and the like. The cylinder array 21 is a lens array having a refractive power in a direction perpendicular to the optical axis γ. The cylinder array 22 has a lens array corresponding to each lens of the cylinder array 21. In the present embodiment, the cylinder array 21 is disposed in front of the lamp 10, and the cylinder array 22 is disposed in front of an ultraviolet absorption filter 23 described later.

  The ultraviolet absorption filter 23 has a function of absorbing ultraviolet rays, and is disposed between the cylinder array 21 and the cylinder array 22. The polarization conversion element 24 has a function of converting non-polarized light into predetermined polarized light, and is disposed in front of the cylinder array 22.

  The front compressor 25 that is a lens is formed of a cylindrical lens having a refractive power in the horizontal direction, and is disposed in front of the polarization conversion element 24. The reflection mirror 26 has a function of reflecting light from the lamp 10 (in this embodiment, converts the optical axis by 90 degrees), and is disposed in front of the front compressor 25.

  The condenser lens 27 collects light from the lamp 10 and forms an image of a light source in the pupil of a projection lens optical system (projection optical system, projection means) 40 to illuminate an object evenly. 26 is arranged in front of. The rear compressor 28 is formed of a cylindrical lens having a refractive power in the horizontal direction, and is disposed in front of the condenser lens 27.

  The light blocking component 29 includes a component such as a diaphragm that blocks the light from the lamp 10 stepwise, or a component such as a shutter that blocks all the light from the lamp 10, and is on the lamp 10 side (incident side). Consists of a reflective mirror.

  The color separation / combination system 30 has a function of decomposing and synthesizing light from the lamp 10, and includes a dichroic mirror 31, a polarizing plate 32, a polarizing beam splitter 33, a quarter wavelength plate 35, and a color selectivity. And a phase difference plate 36 (36a, 36b). The dichroic mirror 31 reflects light in the blue (B) and red (R) wavelength regions, transmits light in the green (G) wavelength region, and is disposed in front of the rear compressor 28.

  The polarizing plate 32 has a function of transmitting only S-polarized light, and includes polarizing plates 32a, 32b, and 32c. The polarizing plate 32 a is a green incident-side polarizing plate in which a polarizing element is bonded to a transparent substrate, transmits only S-polarized light, and is disposed in front of the dichroic mirror 31. The polarizing plate 32 b is a red-blue incident-side polarizing plate in which a polarizing element is bonded to a transparent substrate, and transmits only S-polarized light, and is disposed in front of the dichroic mirror 31. The polarizing plate 32c is a red-blue emission-side polarizing plate (polarizing element) in which a polarizing element is bonded to a transparent substrate, and transmits only S-polarized light.

  The polarization beam splitter 33 has a polarization separation surface, transmits P-polarized light, and reflects S-polarized light, and includes polarization beam splitters 33a, 33b, and 33c. The polarization beam splitter 33a transmits P-polarized light, reflects S-polarized light, and is disposed on the front surface of the polarizing plate 32a. The polarization beam splitter 33b transmits P-polarized light, reflects S-polarized light, and is disposed on the front surface of the color-selective retardation plate 36a. The polarization beam splitter 33c transmits P-polarized light, reflects S-polarized light, and is disposed on the front surface of the polarization beam splitter 33a.

  The quarter wavelength plate 35 has a function of giving a phase difference, and includes quarter wavelength plates 35R, 35G, and 35B. The quarter wavelength plate 35R is disposed between the polarization beam splitter 33b and a liquid crystal display element 50R described later. The quarter wavelength plate 35G is disposed between the polarization beam splitter 33a and a liquid crystal display element 50G described later. The quarter wavelength plate 35B is disposed between the polarization beam splitter 33b and a liquid crystal display element 50B described later.

  The color-selective phase difference plate 36a converts the polarization direction of blue light by 90 degrees and does not convert the polarization direction of red light, and is disposed between the polarizing plate 32b and the polarizing beam splitter 33b. The color-selective retardation plate 36b converts the polarization direction of red light by 90 degrees and does not convert the polarization direction of blue light, and is disposed between the polarizing plate 32c and the polarizing beam splitter 33b.

  The reflective liquid crystal display element 50 (50R, 50G, 50B) is manufactured by enclosing a liquid crystal layer between a glass substrate and a Si substrate. A transparent electrode is disposed on the glass substrate, a semiconductor circuit for driving the reflective liquid crystal display element 50 is formed on the Si substrate, and a reflective electrode is disposed on the surface. The transparent electrode is an ITO electrode, and the reflective electrode is an electrode mainly composed of Al or the like.

  The refractive index anisotropy of the liquid crystal material in the reflective liquid crystal display element 50 is represented by Δn. The refractive index anisotropy is given by the difference between the refractive index ne of the liquid crystal molecules in the major axis direction and the refractive index no in the uniaxial direction. This refractive index value has chromatic dispersion characteristics, and has a unique value for each wavelength.

  Then, by applying a voltage between the transparent electrode and the reflective electrode, by changing the direction of the liquid crystal material existing in the liquid crystal layer, the refractive index anisotropy Δn is changed, and the polarized incident light is changed. It becomes possible to provide a phase difference. Light having a phase difference and a polarization axis different from the incident polarization axis is selectively transmitted or reflected by the polarization beam splitters 33a, 33b, and 33c to be guided and projected to the projection lens optical system 40.

  On the other hand, the light having the same polarization axis as the incident polarization axis without a phase difference is selectively reflected or transmitted by the polarization beam splitters 33a, 33b, and 33c with the opposite characteristics to the above-described characteristics. Go back to.

  The projection lens optical system 40 irradiates light from the high-pressure discharge lamp 10 via the illumination optical system 20 and the color separation / synthesis optical system 30. The projection lens optical system 40 is composed of a plurality of optical elements (not shown) in the lens barrel 40a. In addition, the projection lens optical system 40 includes a shift mechanism 41 that can shift a projection image formed on the screen 500.

(Light source device)
Next, a configuration of a high-pressure discharge lamp device (light source device) 1 including a lamp 10 as a light source, a light source driving unit 12, a control unit 200, and a storage unit 300 will be described with reference to FIG.

  The lamp 10 in this embodiment is an ultra-high pressure mercury lamp, and includes a bulb 11 made of quartz glass and a reflector 18 that reflects light emitted from the bulb. The bulb 11 has a discharge space inside, and a pair of electrodes 14 and 15 made of tungsten are arranged in the discharge space. The electrodes 14 and 15 are sealed on both inner sides of the bulb 11, and the ends of the electrodes 14 and 15 are connected to an external lead wire 17 via a metal foil 16 made of molybdenum.

  The discharge space of the bulb 11 is filled with mercury, a halogen substance, and a rare gas, which are luminescent substances. One side of the valve 11 is fixed to the reflector 18 via a fixing portion 19. The reflector 18 is composed of crystallized glass and a reflecting member, reflects the light emitted from the bulb 11 and irradiates it from the opening side of the reflector 18. The electrode on the fixed part 19 side is referred to as a fixed part electrode 14, and the electrode on the opening side is referred to as the opening side electrode 15.

  The external lead wires 17 are routed outside the reflector 18, and the external lead wires 17 routed outside are connected to the light source driving unit (high-pressure discharge lamp driving unit) 12 so that the controlled lighting power can be obtained. By supplying, the lamp 10 can be turned on.

  The light source driving unit 12 is connected to the control unit 200, and the control unit 200 controls driving conditions such as power supplied from the light source driving unit 12 to the lamp 10 (for example, constant power control is performed). In addition, the driving voltage of the lamp 10 can be detected by the detection unit M including the light source driving unit 12 and the control unit 200. In addition, the storage unit 300 is connected to the control unit 200 and stores the driving voltage of the lamp 10 detected by the control unit 200. Further, the control unit 200 is connected with a counting means (counter) 400 for counting the usage time of the lamp 10 (FIG. 8).

  When light is emitted from the light source driving unit 12, a high voltage pulse is applied to the electrodes 14 and 15 through the external lead wire 17 and the metal foil 16. Then, a discharge is generated between the electrodes 14 and 15. As a result, the temperature of the discharge space of the bulb 11 rises, and the mercury enclosed in the discharge space evaporates. Light emitted when electrons emitted from the electrodes 14 and 15 collide with the evaporated mercury.

  The current mainstream is an AC method in which AC power is applied to the electrodes 14 and 15. Therefore, electrons are alternately emitted from the electrodes 14 and 15, and the electrons collide with the opposing electrodes. It is known that the temperature of the electrode varies depending on the amount of collision of electrons, that is, the amount of current. As in this embodiment, when AC driving is performed with a duty of 50%, currents equal to the electrodes 14 and 15 flow, so the temperatures of the electrodes 14 and 15 are substantially equal and the electrode tips are 3000 ° C. It rises to near.

  The AC frequency of the AC drive lamp is generally 120 Hz or more, and more preferably 360 Hz or more so that flicker is not visually recognized. In this manner, the light emitted from the lamp 10 by the light source driving unit 12 is reflected by the reflector 18 and can be used as an image projection apparatus.

  However, the lamp 10 causes the following phenomenon with the usage time, resulting in a decrease in illuminance and a lamp failure. That is, at the time of lighting, since electrons directly collide with the electrodes 14 and 15, evaporation of tungsten, which is an electrode material, occurs. As a result, evaporated tungsten adheres to the inside of the internal discharge space of the bulb 11. When tungsten adheres, tungsten absorbs light, and the brightness of the lamp 10 decreases. Further, the temperature of the bulb 11 is also increased to nearly 1000 ° C., and the quartz glass is crystallized. When crystallized, the brightness of the lamp 10 decreases.

  Furthermore, if evaporated tungsten adheres to the inside of the internal discharge space of the bulb 11, the temperature inside the discharge space locally rises. As a result, a lamp failure occurs due to the occurrence of local thermal distortion and the crystallization of quartz glass.

  Further, the tungsten, which is the electrode material, evaporates, thereby widening the distance between the electrodes 14 and 15. As a result, the lamp voltage increases as shown in FIG. This change in lamp voltage increases unilaterally over the long term, although there is a minute change in a short time.

  As described above, the lamp 10 has a higher probability that the above-described decrease in brightness and lamp failure will occur with the use time. Accordingly, in the image projection apparatus 100, the lamp 10 can be replaced as a replacement part.

(Determining whether to replace the lamp)
Hereinafter, a flow for determining whether or not to replace the lamp 10 will be described for the control unit 200 that is a determination unit that determines whether or not the lamp 10 is replaced in the present embodiment.

1) Detection of the lamp voltage (lamp voltage stored in the storage unit) immediately before turning off in the previous lighting First, referring to FIG. 1, control when the image projection apparatus 100 is already turned on and the lamp 10 is turned on. The operation of the unit 200 will be described. While the lamp 10 is lit, the control unit 200 detects the lamp voltage from the light source driving unit 12 (Step 1). Then, the lamp voltage detected by the control unit 200 is stored in the storage unit 300 (Step 2). Further, it is confirmed whether or not the user turns off the power of the image projection apparatus 100 (Step 3).

  When the power is not turned off and the device is used continuously, the control unit 200 returns to Step 1 and detects the lamp voltage. On the other hand, when the power is turned off, the flow of FIG. 1 is terminated (Step 4). Accordingly, the storage unit 300 stores the lamp voltage immediately before the lamp is turned off.

2) Detection of the lamp voltage (lamp voltage detected by the control unit) at the current lighting and comparison with the lamp voltage stored in the storage unit Next, referring to FIG. The operation of the control unit 200 when turning on (when the power is turned on) will be described. First, the image projection apparatus 100 is turned on (Step 1). When the power is turned on, the control unit 200 detects the lamp voltage from the light source driving unit 12 (Step 2). Then, the detected lamp voltage is compared with the lamp voltage stored in the storage unit 300 (Step 3). Then, it is detected whether the voltage difference is within a predetermined range (Step 4). If the voltage difference is within a predetermined range, it is determined that the lamp 10 has not been replaced, and thereafter the flow of FIG. 2 is repeated.

  On the other hand, if the voltage difference is not within the predetermined range (larger than the predetermined range), it is determined that the lamp 10 has been replaced (Step 5).

  In this way, when the power of the image projection apparatus 100 is turned on, the lamp voltage is detected and compared with the stored lamp voltage without adding a new component by performing the flow of FIG. The control unit 200 can determine whether or not the lamp has been replaced.

(If it is determined that the lamp has been replaced)
Next, the operation of the control unit 200 when it is determined that the lamp has been replaced by detection by the control unit 200 described above will be described.

1) When voltage change detection is used to automatically reset the lamp usage time In this way, when it is determined that the lamp has been replaced in the image projection apparatus 100, the counting means 400 (FIG. 8) counts. The lamp usage time as a numerical value can be automatically reset. By doing so, when displaying the lamp usage time to the user, it becomes possible to newly record the correct lamp usage time without bothering the user to reset the lamp usage time. This reset makes it possible to correctly display a message to that effect to the user at the appropriate timing before the lamp is burned out and cannot be used when the lamp needs to be replaced next time.

  In addition, not only when the lamp usage time is displayed to the user, but also when the lamp usage time is not displayed to the user (for example, when it is displayed only to a serviceman), a voltage change detection is performed to automatically reset the lamp usage time. Can also be used. By this reset, it is possible to correctly display a message to that effect to the user at the appropriate timing before the lamp is burnt out and cannot be used when the lamp needs to be replaced next time.

2) When using voltage change detection as a preliminary stage for manual reset of lamp usage time When a message such as shown in FIG. 7 is displayed on the operation unit and lamp replacement is detected by voltage change detection, It is also possible to determine whether or not there is a replacement. That is,
The user has an operation section to input whether or not the lamp 10 is to be replaced. A message is displayed so that “Yes” can be selected (input) when the user actually replaces the lamp, and “No” when the lamp is not replaced. To do. By doing so, it is possible to avoid erroneously resetting the lamp usage time automatically even if the voltage change detection that is determined to be lamp replacement is erroneously detected. In this case, the use time of the lamp is manually reset by the user.

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described with reference to the flowchart shown in FIG. The image projection apparatus 100 according to the present embodiment has a mode in which the lamp 10 can be lit with a plurality of electric powers. In general, there are a mode (first mode) in which power consumption is large but can be used brightly, and a mode (second mode) in which brightness is low but power consumption can be reduced. In the present embodiment, there are two power modes A and B.

  Hereinafter, a flow for determining whether or not the lamp 10 has been replaced by the control unit 200 in the present embodiment will be described.

1) Detection of lamp voltage (lamp voltage stored in the storage unit) immediately before turning off in the previous lighting When the power of the image projection apparatus 100 is turned on, the control unit 200 detects lamp power via the light source driving unit 12, Select which power is used to light the lamp (Step 1). And according to the electric power currently used, the control part 200 detects a lamp voltage via the light source drive part 12 (Step2). Then, the lamp voltage detected by the control unit 200 is stored in the storage unit 300 as a value corresponding to each power (Step 3).

  Therefore, in the case of the present embodiment, the storage unit 300 can store the lamp voltage at the time of the lamp power A and the lamp voltage at the time of the lamp power B. Then, it is confirmed whether or not the user turns off the power of the image projection apparatus 100 (Step 4). When the power is not turned off and the camera is used continuously, the control unit 200 returns to Step 1 and detects the lamp power. On the other hand, when the power is turned off, the flow of FIG. 5 is terminated (Step 5). Accordingly, the storage unit 300 stores the lamp voltage immediately before the lamp is turned off.

2) Detection of the lamp voltage (lamp voltage detected by the control unit) at the current lighting, and comparison with the lamp voltage stored in the storage unit Next, referring to FIG. The operation of the control unit 200 when turning on (when the power is turned on) will be described. First, the image projection apparatus 100 is turned on (Step 1). When the power is turned on, the control unit 200 detects lamp power through the light source driving unit 12 and selects which power is used (Step 2). And according to each electric power, the control part 200 detects a lamp voltage via the light source drive part 12 (Step3).

  And the lamp voltage detected according to each electric power and the lamp voltage memorize | stored in the memory | storage part 300 are compared (Step4). Then, it is detected whether the voltage difference is within a predetermined range (Step 5). If the voltage difference is within a predetermined range, it is determined that the lamp 10 has not been replaced, and the flow of FIG. 5 is repeated. On the other hand, if the voltage difference is not within the predetermined range (larger than the predetermined range), it is determined that the lamp 10 has been replaced (Step 6).

  In this way, when the power of the image projection apparatus 100 is turned on, the lamp voltage is detected and compared with the stored lamp voltage without adding a new component by performing the flow of FIG. The control unit 200 can determine whether or not the lamp has been replaced.

(Modification)
As mentioned above, although embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

(Modification 1)
In the above-described embodiment, the drive voltage (lamp voltage) of the lamp 10 as the light source is detected and compared with the stored value to determine whether or not the lamp is replaced. However, the drive current (lamp current) of the lamp 10 is detected and stored. The presence or absence of lamp replacement may be determined by comparing with the value. The light source is not limited to the lamp 10. Further, the illuminated body of the light source device is not limited to the image display element.

(Modification 2)
In addition to determining whether or not to replace the lamp based on the above-described change in lamp voltage or lamp current, other detection means mounted on the image projection apparatus 100 (for example, detection for detecting that the lamp has not been lit). (Means) can also be used. In that case, it is possible to detect the presence or absence of lamp replacement with higher accuracy.

10 .... High pressure discharge lamp, 12 .... Light source drive device, 200 ... Control unit, 300 ... Storage unit

Claims (10)

A light source;
A light source driving unit for driving the light source;
A storage unit for storing a driving voltage or a driving current of the light source obtained through the light source driving unit;
Regarding the driving voltage or driving current of the light source, a determination unit that determines whether or not the light source is replaced by comparing a current value and a value stored in the storage unit;
A light source device comprising:   The light source device according to claim 1, further comprising a counting unit that counts a usage time of the light source, and resetting a count value of the counting unit when the light source is exchanged.   The light source according to claim 1, wherein when the difference between the current value and the value stored in the storage unit is not within a predetermined range, it is determined that the light source has been replaced. apparatus.   4. The light source device according to claim 1, wherein the value stored in the storage unit is a value immediately before the light source is turned off. 5.   The light source device according to claim 1, wherein the current value is a value at the time of power-on. The light source can be selectively lit in a first mode that lights with a first power consumption and a second mode that lights with a second power consumption that is lower than the first power consumption,
6. The light source device according to claim 1, wherein the storage unit stores a value in the first mode and a value in the second mode.   The light source device according to claim 1, further comprising an operation unit that allows a user to input whether or not to replace the light source, in addition to the determination unit.   The light source device according to claim 1, wherein the light source is an ultrahigh pressure mercury lamp. The light source device according to any one of claims 1 to 8,
An image display element;
An illumination optical system for illuminating the image display element;
A color separation / synthesis system that guides light from the illumination optical system to the image display element and guides light from the image display element to a projection surface;
An image projection apparatus comprising:   The image projection apparatus according to claim 9, further comprising a projection optical system that forms an original image formed on the image display element on the projection surface as a projection image.