JP2005078029A - Illumination device and projection display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a large light emission amount by efficiently cooling a light emitter.
SOLUTION: A container 21 having a closed space in which a cooling fluid X is enclosed, and a light emitter 25 that is arranged adjacent to the container 21 and emits light and generates heat by being injected with an electric current are provided. The shape change parts 22 and 24 which change the space shape of space, and the tracking part 22 which follows the change of the space shape of the said closed space are provided.
[Selection] Figure 3

Description

  The present invention relates to an illumination device and a projection display device.

  In conventional projectors (projection display devices), a halogen lamp has been used as a light source in the past, and a high-pressure mercury lamp (UHP) having high luminance and high efficiency has been used in recent years. A light source using UHP, which is a discharge lamp, requires a high-voltage power circuit, is large and heavy, and hinders the reduction in size and weight of the projector. Further, although it has a longer life than a halogen lamp, it still has a short life, and it is almost impossible to control the light source (fast lighting, extinguishing, modulation), and it takes a long time to start up.

  Therefore, recently, an LED illuminant has attracted attention as a new light source. LEDs are ultra-compact, ultra-light, and have a long life. In addition, by controlling the drive current, it is possible to freely turn on / off and adjust the amount of emitted light. In this respect, it is also promising as a light source for a projector, and application development to a small-sized and portable small-screen projector has already begun (for example, Patent Document 1).

  However, at present, it is difficult to obtain sufficient luminance in a projector using an LED as a light source. This is because the LED is still about 1/2 to 1/3 of UHP in terms of efficiency, and the amount of light that can be obtained even when a full current is injected is small. The above-mentioned efficiency is steadily improving year by year due to remarkable technological innovation, and may reach the level of the current UHP in a few years, but the situation will change at least for LED light source projectors that can be commercialized in the near future. There will be no. There is a method of arraying LEDs in order to increase the amount of light, but if the number of LEDs is increased too much, the light emission point becomes large and the illumination light rate as an optical system is lowered, so that the effect is not obtained so much. .

  Therefore, a possible remaining method is to increase the light emission amount of the LED. However, as described above, there is a limitation on the rating of the LED, and the maximum light amount is automatically determined by the rating and efficiency. It is mainly the calorific value that determines the rated current of the LED.

Incidentally, Japanese Patent Application Laid-Open No. 6-5923 (Patent Document 2) discloses a technique for obtaining a large light emission amount by cooling an LED with a cooling fluid. Japanese Patent Application Laid-Open No. 8-116138 discloses a technique for obtaining a large light emission amount by cooling a light emitting body as in Patent Document 2, although it is an example of a laser diode.
Japanese Patent Laid-Open No. 2000-112031 JP-A-6-5923 JP-A-8-116138

  However, all of the techniques disclosed in Patent Documents 2 and 3 require a pumping means for allowing a cooling fluid to flow into a container surrounding the light emitter and a pipe connecting the pumping means and the container. Since such pumping means and piping are provided, the cost of the entire apparatus is greatly increased and the entire apparatus is increased in size. In particular, in the case of the projector as described above, it is not preferable to use a large-sized pumping means because it goes against the trend of reducing the size and weight of the projector. For this reason, the technique which can cool a light-emitting body, without enlarging an apparatus is calculated | required.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to obtain a large light emission amount by efficiently cooling a light emitter.

  In order to achieve the above object, a lighting device according to the present invention emits light and generates heat when a container having a closed space in which a cooling fluid is sealed, and a container disposed adjacent to the container and injected with current. A light-emitting body, and a shape changing unit that changes a space shape of the closed space; and a follower that follows the change of the space shape of the closed space.

  According to the lighting device according to the present invention having such characteristics, an external force acts on the cooling fluid sealed in the container by changing the space shape of the container by the shape changing unit. At this time, the follower follows the change in the space shape of the container, so that the cooling fluid moves in the container. And when a shape change part returns to an original state, while a follower part also returns to an original state, the fluid for cooling will also flow so that it may be in an original state. By repeatedly performing such a change of the space shape of the shape changing portion, a cooling fluid flows in the container. Therefore, heat exchange between the light emitter adjacent to the container and the cooling fluid is promoted, and the light emitter can be efficiently cooled. For this reason, the light emitter can be driven with a large current, and a large light emission amount can be obtained from the light emitter.

  According to such a lighting device according to the present invention, there is no need for a pumping means for allowing a cooling fluid to flow into the container and a pipe for connecting the pumping means and the container. This makes it possible to obtain a large amount of light emission from the light emitter while preventing the device from becoming large.

Further, as the shape changing section, a configuration including a flexible diaphragm and a driving device that deforms the diaphragm can be employed. According to the lighting device according to the present invention having such a configuration, the space shape of the container can be easily changed by deforming the diaphragm by the driving device.
As this driving device, a voice coil motor and a piezoelectric element can be used, and a device that deforms a diaphragm using an electrostatic force can be adopted.

  The drive device is preferably driven at a frequency outside the audible band. In this way, by driving the drive device at a frequency outside the audible band, the diaphragm also repeats reciprocating motion at a frequency outside the audible band, so that it is possible to prevent noise from being generated from the lighting device according to the present invention. . In addition, since a light-emitting body can be cooled even if the flow of the cooling fluid is not so fast, the driving device is preferably driven at a frequency of 20 Hz or less, for example.

  Moreover, it is preferable that the illuminating device which concerns on this invention is provided with the flow direction prescription | regulation part which prescribes | regulates the moving direction of the said cooling fluid. By providing such a flow direction defining portion, the cooling fluid can be circulated in the container, and the luminous body can be cooled using the entire cooling fluid.

  Moreover, the illuminating device which concerns on this invention can also employ | adopt the structure of providing the said light-emitting body in multiple numbers. As described above, even in the case where a plurality of light emitters arranged adjacent to the container are provided, the lighting device according to the present invention is efficiently provided by supplying a flow to the cooling fluid enclosed in the container. A plurality of light emitters can be cooled simultaneously.

  Moreover, the illuminating device which concerns on this invention can also comprise a part of said diaphragm as said tracking part. For example, when a single diaphragm is disposed on the bottom surface of the container and the central portion of the diaphragm is pressed by the driving device, an external force acts on the cooling fluid, and the cooling fluid presses the vicinity of the periphery of the diaphragm. As a result, the vicinity of the periphery of the diaphragm is deformed. For this reason, the periphery vicinity of this diaphragm can be used as a tracking part. In addition, it becomes possible to make the vicinity of the periphery of the diaphragm follow the change of the space shape of the container by arranging a fixing portion that fixes the diaphragm between the vicinity of the periphery of the diaphragm and the central portion.

  Further, by arranging the diaphragm so that the closed space is separated into the upper layer and the lower layer, the surface on one side of the diaphragm can be configured as a shape changing portion and the surface on the other side can be configured as a follower. In such a case, the upper or lower cooling fluid is pressed by the deformation of the diaphragm, and the cooling fluid of the other layer is attracted to the diaphragm, so that the movement of the cooling fluid can be further increased. The cooling effect of the luminous body is further increased.

  Moreover, it is preferable that the illuminating device which concerns on this invention has a thermal radiation part in the said container. Thus, by having the heat radiating part in the container, it becomes possible to efficiently radiate the heat quantity of the light emitting body recovered by the cooling fluid to the outside. As this heat radiating portion, a heat radiating fin having a large surface area with respect to the formation region can be employed.

  Next, a projection display device according to the present invention includes the illumination device according to the present invention as a light source. Therefore, it is possible to provide a projection display device that is small and light and has a large light emission amount.

  Hereinafter, an embodiment of an illumination device and a projection display device according to the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic configuration diagram of a projection display device according to the present embodiment. As shown in this figure, the projection display device according to the present embodiment is a three-plate liquid crystal projector, and each of the three light incident surfaces 30R, 30G, and 30B of the cross dichroic prism 30 serving as a color synthesizing unit is provided on each of them. Transmission type liquid crystal devices 20R, 20G, and 20B as light modulation devices are arranged to face each other, and R (red) and G are respectively provided on the back side (the side opposite to the cross dichroic prism 30) of each liquid crystal device 20R, 20G, and 20B. Light sources 10R, 10G, and 10B capable of emitting (green) and B (blue) color light are arranged.

  As shown in FIG. 2, the light source 10 (10R, 10G, 10B) includes a plurality of light emitting elements 11 (illuminating devices) that emit the same color light, and a substrate 12 on which the light emitting elements 11 are arranged on one side. I have. Each light emitting element 11 is formed of a light emitting diode (LED), for example, and is turned on by a lighting control circuit (not shown).

3 is a schematic configuration diagram of the light-emitting element 11 shown in FIG. 2, in which (a) is a cross-sectional view, and (b) is a top view showing a part of the light-emitting element 11 from the top.
As shown in FIG. 3A, the light emitting element 11 includes a container 21, a diaphragm 22, a driving device 24, and a light emitting chip 25 (light emitter).
And, as shown in the figure, a closed space is formed by a recess formed in the container 21 and a diaphragm 22 fixed to the side of the container 21 so as to close the recess, and in this closed space, A cooling fluid X is enclosed. The container 22 is preferably formed of a member having high heat conductivity such as metal. The diaphragm 22 is a flexible plate-like member, and a driving device 24 for pressing the central portion of the diaphragm 22 is disposed below the central portion of the diaphragm 22. As the driving device 24, a voice coil motor, a piezoelectric element, or the like that is displaced when a voltage is applied can be used. The light emitting chip 25 is a chip that emits light and generates heat when current is injected from the lighting control circuit, and is disposed adjacent to the upper surface of the container 21 while being accommodated in the lens 26.

The light emitting element 11 includes a fixing portion 23 supported by the container 21 by a support portion (not shown) and a heat radiation fin 27 (heat radiation portion).
The fixed portion 23 is disposed adjacent to the diaphragm 22, and a plurality of the fixed portions 23 are disposed so as to surround the central portion of the diaphragm 22 as shown in FIG. That is, the portion of the diaphragm 22 adjacent to the fixing portion 23 is not deformed by being fixed by the fixing portion 23. Here, a configuration is adopted in which the fixing portion 23 is supported by the container 21 by a support portion (not shown). However, by increasing the thickness of the fixing portion 23, the fixing portion 23 is directly fixed to the container 21. It may be good or one.
Moreover, the radiation fin 27 is configured as a plurality of upright plate-like members having a larger surface area than the region where the radiation fin 27 is formed, and the light emitting chip is formed on the upper surface of the container 21 as shown in FIG. 25 so as to surround 25.
In the present embodiment, the shape changing unit according to the present invention includes the diaphragm 22 and the driving device 24.

In the light emitting element 11 configured as described above, when the central portion of the diaphragm 22 is pressed by driving the driving device 24, the central portion of the diaphragm 22 is displaced upward as shown in FIG. 3A. To do. As a result, the space shape of the closed space is changed, and the cooling fluid X staying in the vicinity of the center of the diaphragm 22 flows toward the periphery of the diaphragm 22. At this time, since the diaphragm 22 has flexibility, the diaphragm 22 is pressed by the cooling fluid X that flows toward the periphery of the diaphragm 22. Therefore, the portion (near the periphery) of the diaphragm 22 located on the outer side of the fixed portion 23 is displaced downward in the drawing as shown in FIG. That is, the vicinity of the periphery (following portion) of the diaphragm 22 is displaced following the change in the closed space caused by the driving of the driving device 24. Therefore, the cooling fluid X can easily flow toward the periphery of the diaphragm 22.
Subsequently, when the driving device 24 returns to the original state, the central portion of the diaphragm 22 that has been deformed by being pressed returns to the original state. Along with this, the cooling fluid X flowing toward the periphery of the diaphragm 22 returns to the original state, and the flow of the cooling fluid X occurs in the closed space.

  By repeatedly changing the shape of the closed space, the cooling fluid X in the closed space can always have a flow. Accordingly, since heat exchange between the light emitting chip 25 and the cooling fluid X can be promoted, the light emitting chip 25 can be easily cooled. For this reason, the light emitting chip 25 can be driven with a large current, and a large light emission amount can be obtained from the light emitting element 11.

  Further, the heat quantity of the light-emitting chip 25 collected by the cooling fluid X is radiated to the outside through the container 21, but the container 21 is formed of a metal having high heat conductivity and the container 21. Since the heat radiation fins 27 are disposed on the surface, the amount of heat recovered by the cooling fluid X is efficiently radiated to the outside. For this reason, the temperature rise of the cooling fluid X can be prevented, and the light emitting chip 25 can be cooled more reliably.

  The driving device 24 is preferably driven at a frequency outside the audible band. In this way, by driving the driving device 24 at a frequency outside the audible band, the diaphragm 22 also repeats reciprocating motion at a frequency outside the audible band, so that it is possible to prevent noise from being generated from the light emitting element 11.

  Therefore, according to such a light emitting element 11, there is no need for a pumping means for allowing the cooling fluid X to flow into the container 21 and a pipe connecting the pumping means and the container 21. A large amount of light emission can be obtained from the light emitting chip 25 while preventing an increase in cost and an increase in the size of the light emitting element 11.

  Returning to FIG. 1, the illuminance for making the illuminance distribution of illumination light uniform between the light sources 10R, 10G, and 10B and the corresponding light modulators 20R, 20G, and 20B in the light modulators 20R, 20G, and 20B. As the uniformizing means 19, a first fly-eye lens 191 and a second fly-eye lens 192 are sequentially installed from the lighting device side. The first fly-eye lens 191 forms a plurality of secondary light source images, and the second fly-eye lens 192 functions as a superimposing lens that superimposes them at the installation position of the light modulation device that is the illuminated area. Thereby, the light emitted from the light emitting element 1 is irradiated on the entire surface of the liquid crystal device with a uniform density regardless of the density distribution of the light.

  The cross dichroic prism 30 has a structure in which four right-angle prisms are bonded together, and light reflection films (not shown) made of a dielectric multilayer film are formed in a cross shape on the bonding surfaces 30a and 30b. Specifically, light reflection that reflects red image light formed by the light modulation device 20R and transmits green and blue image light formed by the light modulation devices 20G and 20B to the bonding surface 30a, respectively. A light reflection that reflects the blue image light formed by the light modulation device 20B and transmits the red and green image light formed by the light modulation devices 20R and 20G, respectively, is provided on the bonding surface 30b. A membrane is provided. The image light of each color guided to the light exit surface of the cross dichroic prism 30 is projected onto the screen 50 by a projection lens (projection means) 40.

  Therefore, according to the projection display device according to the present embodiment, since the light emitting element 11 that can obtain a large light emission amount from the light emitting chip 25 while preventing an increase in size is provided as a part of the light source 10, the small size is achieved. In addition, the projection display device is lightweight and has a large light emission amount.

(Second Embodiment)
FIG. 4 is a diagram showing a cross section of a light emitting element 11a having a configuration different from that of the first embodiment. In the second embodiment, only different parts from the first embodiment will be described.
As shown in FIG. 4, in the light emitting device 11a according to the second embodiment, the closed space formed in the container 21 is separated into an upper layer and a lower layer, and the upper layer and the lower layer are separated from each other. A diaphragm 22 is disposed at the center of the partition plate 21a. That is, in the light emitting element 11a according to the second embodiment, the diaphragm 22 is arranged so as to separate the closed space into an upper layer and a lower layer. The partition plate 21a is fixed to the container 21 by a support portion (not shown), and its end is supported in a non-contact manner with the side wall portion of the container 21 as shown. That is, in the light emitting element 11a according to the second embodiment, the upper layer and the lower layer of the closed space are connected in the vicinity of the periphery of the closed space. And the drive device 24 is arrange | positioned from the inside of closed space to the exterior of the container 24 so that the drive part may be arrange | positioned under the diaphragm 22. FIG.

  When the driving device 24 is driven in the light emitting element 11a according to the second embodiment having such a configuration, the diaphragm 22 is displaced upward in the drawing. As a result, the volume of the upper layer of the closed space decreases, and the volume of the lower layer of the closed space increases accordingly. In this case, the cooling fluid X staying in the upper layer of the closed space flows toward the periphery of the closed space as the diaphragm 22 is deformed, and at the same time, the cooling fluid X staying in the lower layer of the closed space is It flows toward the center of the closed space with deformation. Here, since the upper layer and the lower layer of the closed space are connected in the vicinity of the peripheral edge of the closed space, the force that causes the cooling fluid X to flow toward the center of the closed space in the lower layer of the closed space is It is transmitted to the cooling fluid X in the upper layer. In other words, the cooling fluid X in the upper layer of the closed space is pushed away as the diaphragm 22 is deformed, and is drawn toward the lower layer of the closed space. Accordingly, since the movement of the cooling fluid X in the upper layer of the closed space can be increased, the amount of heat of the light emitting chip 25 can be recovered more efficiently, and the light emitting chip 25 can be driven with a larger current.

(Third embodiment)
Next, FIG. 5 is a diagram showing a schematic configuration of a light emitting element 11b having a configuration different from that of the first and second embodiments, in which (a) is a cross-sectional view and (b) is one of the light emitting elements 11b. It is the top view which showed the part from the upper surface. In the third embodiment, only parts different from the first embodiment will be described.
As shown in FIGS. 5A and 5B, the light emitting element 11b according to the third embodiment includes a flow direction defining portion 28 that defines the flow direction of the cooling fluid X enclosed in the closed space. I have. The flow direction defining portion 28 is a film-like member surrounding the central portion of the diaphragm 22, and includes a first flow direction defining portion 28a that regulates the flow of the cooling fluid X from the central portion of the closed space toward the periphery. The second fluid flow direction defining portion 28b defines the flow of the cooling fluid so as to be directed from the vicinity of the peripheral edge of the closed space toward the central portion.

  As shown in FIG. 5 (b), the first flow direction defining portion 28a is disposed so as to surround the central portion of the diaphragm 22 by a half circumference (upper side of the paper surface in FIG. 5 (b)), and the lower portion is fixed. It is fixed to the upper surface of the part 24, and its posture is defined so that its upper part faces the vicinity of the peripheral edge of the closed space. As shown in FIG. 5A, the upper portion of the first flow direction defining portion 28a is in contact with the container 21, but not fixed. Therefore, when the cooling fluid X tries to flow from the central portion of the closed space to the vicinity of the peripheral edge, the cooling fluid X is allowed to pass through, but conversely, the cooling fluid X flows from the vicinity of the peripheral edge of the closed space to the central portion. In this case, the cooling fluid X is not allowed to pass.

  Further, as shown in FIG. 5B, the second flow direction defining portion 28b is arranged so as to surround the central portion of the diaphragm 22 by a half circumference (the lower side of the drawing in FIG. 5B). The posture is regulated so that the lower part is fixed to the upper surface of the fixed part 24 and the upper part is directed to the central part of the closed space. As shown in FIG. 5A, the upper portion of the first flow direction defining portion 28b is in contact with the container 21 but not fixed. Therefore, when the cooling fluid X is about to flow from the vicinity of the peripheral edge of the closed space to the central portion, the cooling fluid X is allowed to pass through, but conversely, the cooling fluid X is likely to flow from the central portion of the closed space to the vicinity of the peripheral edge. In this case, the cooling fluid X is not allowed to pass.

  In the light emitting element 11b according to the third embodiment having such a configuration, when the driving device 24 is driven, the diaphragm 22 is displaced upward in the drawing in FIG. In this case, since the cooling fluid X tends to flow from the central portion of the closed space toward the vicinity of the peripheral edge of the closed space, the cooling fluid X passes through the first flow direction defining portion 28a and flows in the vicinity of the peripheral edge of the closed space. When the diaphragm 22 returns to the original state, the cooling fluid X tends to flow from the vicinity of the peripheral edge of the closed space toward the center portion, and thus passes through the second flow direction defining portion 28b and closes the closed space. Flowing in the middle of the. Then, by repeatedly driving the driving device 24, the cooling fluid X staying in the central portion of the closed space flows in the vicinity of the peripheral edge of the closed space via the first flow direction defining portion 28a, and then the flow direction is defined. It returns to the central part of the closed space again via the part 28b. Therefore, the flow of the cooling fluid X in the closed space can be a circulation flow. By making the flow of the cooling fluid X into a circulation flow in this way, all the cooling fluid X can be used for cooling the light emitting chip 25, and thus the light emitting chip 25 can be efficiently cooled. .

  When such a configuration is adopted, gaps are formed between the first flow direction defining portion 28a and the second flow direction defining portion 28b and between the flow direction defining portion 28 and the diaphragm 22, Some cooling fluid X enters and exits in the gap. However, in order to cool the light emitting chip 25, the flow of the cooling fluid X does not need to be a complete circulation flow, and thus the cooling fluid X does not enter and exit in such a gap.

The first and second flow direction defining portions 28a and 28b according to the third embodiment are not necessarily film-like members, and have, for example, a configuration as shown in FIGS. 6 (a) and 6 (b). There may be.
The first and second flow direction defining portions 28a1 and 28b1 shown in FIG. 6A include a pipe 31 whose pipe diameter is widened at the midway part 31a and a plug member that plugs the midway part 31a of the pipe 31 via a spring 33. 32. According to the first and second flow direction defining portions 28a1 and 28b1 having such a configuration, only the cooling fluid X that flows from the right side of the paper surface is allowed to pass, and conversely, the cooling fluid that flows from the left side of the paper surface Since X is not allowed to pass through, the flow of the cooling fluid X can be defined so that the flow of the cooling fluid X is directed from the right to the left in the drawing.
Moreover, the first and second flow direction defining portions 28a2 and 28b2 shown in FIG. 6B are so-called fluidic diodes, and a main body portion 34 that is set in a hollow cylindrical shape, and the center of the upper surface of the main body portion 34. A first pipe 36 connected to the part, a second pipe 35 connected to the first pipe at an angle, and a third pipe connected to the body part 34 and extending in the tangential direction of the body part 34 37. According to the first and second flow direction defining portions 28a2 and 28b2 having such a configuration, the cooling fluid X easily flows in the order of the second pipe 35 → the first pipe 36 → the third pipe 37. The flow of the cooling fluid X can be defined so as to be directed from the left to the right of the drawing.

  The light emitting element 11b according to the third embodiment may include the first and second flow direction defining portions 28a1, 28b1, 28a2, and 28b2 as shown in FIGS. 6 (a) and 6 (b). Is possible. However, the first and second flow direction defining portions 28a1, 28b1, 28a2, and 28b2 as shown in FIGS. 6 (a) and 6 (b) are film-like first and second flow direction defining portions 28a and 28b. However, the structure becomes complicated, and further, a structure for allowing the cooling fluid X to flow into the pipe 31 and the second pipe 35 is necessary, which increases the manufacturing cost of the light emitting element. Therefore, the light emitting element 11b according to the third embodiment preferably includes the film-like first and second flow direction defining portions 28a and 28b.

(Fourth embodiment)
Next, FIG. 7 is a cross-sectional view of the light emitting element 11c that displaces the diaphragm 22 using electrostatic force. In the fourth embodiment, only parts different from the first embodiment will be described.
As shown in FIG. 7, the light emitting element 11c according to the fourth embodiment uses an electrostatic force instead of the driving device 24 that displaces the diaphragm 22 using the voice coil motor or the piezoelectric element shown in the above embodiment. The driving device 41 for displacing the diaphragm 22 is provided.
In the light emitting element 11c according to the fourth embodiment, the diaphragm 22 is separated into a first diaphragm 22a disposed in the central portion of the closed space and a second diaphragm 22b disposed in the vicinity of the peripheral edge of the closed space. An insulating portion 29a is disposed between the first diaphragm 22a and the second diaphragm 22b. Accordingly, the first diaphragm 22a and the second diaphragm 22b are electrically insulated. The insulating portion 29a is arranged so as to surround the first diaphragm 22a, and is not arranged in a plurality as in the fixing portion 23 shown in FIG. 3B, but over the entire circumference of the first diaphragm 22a. Is formed. The insulating portion 29a is also fixed to the container 21 via a support portion (not shown).

The first diaphragm 22a and the container 21 are formed of a conductive metal material, and the power source of the driving device 41 is connected to the first diaphragm 22a and the container 21.
The drive device 41 uses the first diaphragm 22a and the container 21 as electrodes, and applies an AC voltage to the first diaphragm 22a and the container 21, thereby generating an electrostatic force acting between the first diaphragm 22a and the container 21. This is used to displace the first diaphragm 22a. Therefore, the drive device 41 according to the fourth embodiment uses the first diaphragm 22a itself that is a drive target as one of its components.
And the 1st diaphragm 22a is displaced by the drive of such a drive device 41. FIG. Therefore, the light emitting element 11c according to the fourth embodiment can cause the cooling fluid X to flow by the displacement of the first diaphragm 22a, and can efficiently cool the light emitting chip 25.

(Fifth embodiment)
Next, FIG. 8 is a cross-sectional view of a light emitting element 11d which is a modification of the light emitting element 11c that displaces the diaphragm 22 using the electrostatic force shown in the fourth embodiment. In the fifth embodiment, only parts different from the fourth embodiment will be described.
As shown in FIG. 8, the light emitting element 11c according to the fifth embodiment includes an electrode 42 fixed to the container 21 through an insulating portion 29b. The power source of the driving device 41 is electrically connected to the electrode 42 instead of the container 21. In this way, since the electrode 42 insulated from the container 21 is provided, it is not necessary to insulate the diaphragm 22 and the container 21 from each other. Therefore, the diaphragm 22 is replaced with the first diaphragm 22a and the second diaphragm as in the fourth embodiment. There is no need to separate it into 22b. Therefore, as shown in FIG. 8, a single diaphragm 22 can be used. In this case, since it is not necessary to arrange the insulating portion 29a in the fourth embodiment, the fixing portion 23 shown in the first embodiment may be disposed. In addition, when the container 21 is formed with the material which does not have electroconductivity, it is not necessary to provide the insulation part 29b, and the electrode 42 can be fixed to the container 21 directly.
And the diaphragm 22 is displaced by the drive of the drive device 41. Therefore, the light emitting element 11d according to the fifth embodiment can cause the cooling fluid X to flow due to the displacement of the diaphragm 22, and can efficiently cool the light emitting chip 25.

(Sixth embodiment)
Next, FIG. 9 is a cross-sectional view of a light emitting element 11e which is a modification of the light emitting element 11c that displaces the diaphragm 22 using the electrostatic force shown in the fourth embodiment. In the sixth embodiment, only portions different from the fourth embodiment will be described.
As shown in FIG. 9, the light emitting element 11 e according to the sixth embodiment is provided with an insulating part 29 c as a lower part of the container 21. Thus, since the diaphragm 22 and the container 21 are insulated by providing the insulating portion 29c as the lower part of the container 21, the diaphragm 22 can be separated from the first diaphragm 22a and the second diaphragm 22b as in the fourth embodiment. There is no need for separation. Therefore, as shown in FIG. 9, a single diaphragm 22 can be used. In this case, since it is not necessary to arrange the insulating portion 29a in the fourth embodiment, the fixing portion 23 shown in the first embodiment may be disposed.
Further, in the light emitting element 11e according to the sixth embodiment, as shown in FIG. 9, a portion of the container 21 located above the central portion of the diaphragm 22 is formed to protrude. For this reason, the space between the electrodes of the driving device 41, that is, the space between the diaphragm 22 and the container 21 is narrowed, so that the electrostatic force acts strongly. Therefore, since the center part of the diaphragm 22 can be largely displaced, the moving amount of the cooling fluid X can be increased, and the light emitting chip 25 can be cooled more efficiently.

(Seventh embodiment)
Next, FIG. 10 is a cross-sectional view of a light emitting element 11f which is a modification of the light emitting element 11c shown in the fifth embodiment. In the seventh embodiment, only parts different from the fifth embodiment will be described.
As shown in FIG. 10, in the light emitting element 11f according to the seventh embodiment, an insulating portion 29d is disposed on the lower surface of the diaphragm 22 so as to surround the center portion of the diaphragm 22, and the insulating portion 29d is interposed therebetween. The electrode 42 is disposed opposite to the central portion of the diaphragm 22. In this case, since the insulating portion 29d can fix the center portion of the diaphragm 22 and the vicinity of the peripheral edge, it is not necessary to provide the fixing portion 23.
In the light emitting element 11f according to the seventh embodiment having such a configuration, the diaphragm 22 is displaced downward in the drawing by driving of the driving device 41. In this case, the cooling fluid X staying near the periphery of the closed space flows toward the central portion of the closed space. Therefore, the light emitting element 11 f according to the seventh embodiment can cause the cooling fluid X to flow due to the displacement of the diaphragm 22 and efficiently cool the light emitting chip 25.

  As mentioned above, although preferred embodiment of the illuminating device and projection type display apparatus which concern on this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the said embodiment, the light emitting chip 25 adjacent to the container 21 was demonstrated as one. However, the lighting device according to the present invention is not limited to this, and a plurality of light emitting chips may be disposed adjacent to the container 21. As described above, by arranging the plurality of light emitting chips 25 on the container 21, these light emitting chips can be cooled together, so that the light emitting chips can be cooled more efficiently.

1 is a schematic configuration diagram of a projection display device according to a first embodiment of the present invention. It is a schematic block diagram of the plateau 10 used for a projection type display apparatus. It is a schematic block diagram of the light emitting element 11 which concerns on 1st Embodiment of this invention. It is a schematic block diagram of the light emitting element 11a which concerns on 2nd Embodiment of this invention. It is a schematic block diagram of the light emitting element 11b which concerns on 3rd Embodiment of this invention. It is the figure which showed the modification of the flow direction control parts 28a and 28b used for the light emitting element 11b. It is a schematic block diagram of the light emitting element 11c which concerns on 4th Embodiment of this invention. It is a schematic block diagram of the light emitting element 11d which concerns on 5th Embodiment of this invention. It is a schematic block diagram of the light emitting element 11e which concerns on 6th Embodiment of this invention. It is a schematic block diagram of the light emitting element 11f which concerns on 7th Embodiment of this invention.

Explanation of symbols

11, 11a to 11f: Light emitting element (illuminating device), 21: Container, 22: Diaphragm, 24: Driving device, 25: Light emitting chip (light emitting body), 27: Radiating fin (heat radiating part), X: Cooling fluid

Claims (12)

A container having a closed space in which a cooling fluid is sealed, and a light emitter that is arranged adjacent to the container and emits light and generates heat when current is injected,
An illumination device comprising: a shape changing unit that changes a space shape of the closed space; and a tracking unit that follows the change of the space shape of the closed space. The lighting device according to claim 1, wherein the shape changing unit includes a flexible diaphragm and a driving device that deforms the diaphragm. The lighting device according to claim 2, wherein the driving device is a voice coil motor. The lighting device according to claim 2, wherein the driving device is a piezo element. The lighting device according to claim 2, wherein the driving device deforms the diaphragm using an electrostatic force. The lighting device according to claim 2, wherein the driving device is driven at a frequency outside the audible band. The lighting device according to claim 1, further comprising a flow direction defining portion that defines a moving direction of the cooling fluid. The lighting device according to claim 1, comprising a plurality of the light emitters. The lighting device according to claim 2, wherein a part of the diaphragm is configured as the follower. The lighting device according to claim 9, wherein the diaphragm is disposed so as to separate the closed space into an upper layer and a lower layer. The lighting device according to claim 1, wherein the container has a heat radiating portion. A projection display device comprising the illumination device according to claim 1 as a light source.

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