JP4289088B2 - Light source device - Google Patents

Description

  The present invention relates to a light source device in which a light emitting element is directly or indirectly cooled by a cooling fluid, and a projector on which the light source device is mounted.

In recent years, electronic devices such as projectors that use solid-state light sources such as light-emitting diodes (LEDs) for illumination have been promoted in downsizing and high brightness, and the heat density in the device has increased compared to conventional devices. There is a need to further improve the cooling performance of the light source device, which is a heat source.
Moreover, although LED chip is coat | covered with translucent resin, translucent resin generally has low heat conductivity. Therefore, the heat generated in the LED chip is radiated through the light emitting element substrate and the lead wire to which the LED chip is fixed. However, as the brightness of the light source device increases and the output increases, sufficient heat dissipation cannot be obtained. It is coming.

  Conventionally, a light source device that directly cools an LED chip as a light emitting element with a cooling fluid has been proposed. At this time, a structure for cooling by natural convection of a sealed cooling fluid, a structure for cooling by the principle of a heat pipe, a structure for cooling by flowing a cooling gas, and the like are known (for example, see Patent Document 1).

  In addition, the LED chip or the substrate to which the LED chip is fixed is cooled with a cooling liquid in a sealed container or a structure in which a translucent insulating fluid is flowed from the outside of the container to cool the LED chip, and the LED chip is overheated. There is known a light source device in which a flow path in which a cooling liquid flows and a flow path in which a cooled cooling liquid flows are separated (see, for example, Patent Document 2).

  There is also known a light source device in which an LED chip is fixed to a substrate and cooled by a cooling liquid in a sealed container, and fins are provided on the substrate or the container in contact with the cooling liquid ( For example, see Patent Document 3).

Alternatively, a structure is known in which a cooling liquid circulation path is provided on a substrate on which a heat sink and an LED chip are mounted, the cooling liquid is enclosed in the circulation path and the cover, and natural convection is performed in the circulation path and the cover (for example, , See Patent Document 4).
Japanese Patent Laid-Open No. 11-163410 (page 3, page 4, FIGS. 1 to 4) Japanese Laid-Open Patent Publication No. 2001-36148 (page 1, pages 9 to 10, FIG. 1, FIG. 32) Japanese Laid-Open Patent Publication No. 2001-36153 (Page 3, Figures 1 and 3) Japanese Laid-Open Patent Publication No. 61-168372 (Page 3, Fig. 1)

Since Patent Document 1 has a structure in which the liquid is cooled with a sealed liquid, there is a problem that the cooling speed is slow because the liquid is only circulated in the container by natural convection. Moreover, in the structure which cools by the principle of a heat pipe, there exists a subject that a bubble tends to generate | occur | produce in a liquid and a bubble reduces the cooling effect.
Further, in the structure in which the cooling gas is flowed to directly cool the LED chip, there is a problem that a sufficient cooling effect cannot be obtained because the gas has a lower thermal conductivity than the metal.

In Patent Document 2, since the cooling liquid is introduced from the outside of the container and flows inside the container and flows out of the container, the cooling liquid is more effective than cooling by natural convection. Since the path and the outflow channel are not controlled with respect to the LED chip, there is a problem that the circulation of the cooling liquid is poor and the cooling efficiency is low.
In addition, since the circulation of the cooling liquid is poor, in order to cool the high-luminance, high-power light-emitting elements used for projectors and the like, the flow rate of the cooling liquid must be increased. There is a problem that the mechanism needs to be large and complicated, and as a result, the cost of the light source device becomes high.
Further, when the flow rate of the cooling liquid is increased, the pressure in the container is increased, and stress is generated in the LED chip itself and the electrode part (wire bonding part) connecting the LED chip, which reduces the reliability of the light source device. There are also problems like this.

  Further, in Patent Document 3, a heat sink fin is provided on a substrate or a container to which an LED chip is fixed. However, since the cooling liquid is hermetically sealed and only naturally convected, sufficient cooling performance is obtained. There is a problem that cannot be done. Moreover, in such a structure, since the distance between the LED chip and the heat radiating fin has to be increased from the structural strength, there is a problem that sufficient cooling performance cannot be obtained.

  Further, in Patent Document 4, a cooling liquid circulation path is provided on the substrate on which the heat sink and the LED chip are mounted, and the cooling liquid is enclosed in the circulation path and the cover, and is naturally convected in the circulation path and the cover. And there is a problem that the cooling efficiency is poor because the flow path of the cooling liquid is limited within the heat sink.

The object of the present invention is to force the cooling fluid to flow directly or indirectly through the light emitting element.
It is an object of the present invention to provide a light source device with improved cooling effect and a projector equipped with the light source device.

The light source device of the present invention is a light source device in which a light emitting element is cooled by a cooling fluid, a light emitting element base to which the light emitting element is fixed, an inflow path of the cooling fluid to the light emitting element base, and an outflow The inflow path and the outflow path are provided substantially parallel to the surface of the light emitting element base to which the light emitting element is fixed.
Here, a light emitting diode (LED) can be adopted as the light emitting element, and the planar shape is formed in a substantially square or circular shape. As the cooling fluid, a gas such as nitrogen gas (N ₂ ) or argon gas (Ar), or a liquid such as pure water, fluorine-based hydrocarbon, or silicon oil can be used.
In addition, as a material for the light emitting element base and the cooling structure, an aluminum alloy or a copper-based metal having a higher thermal conductivity than the cooling fluid can be employed.

  According to the present invention, the light emitting element can be cooled directly or indirectly by the cooling fluid, but the inflow path and the outflow path of the cooling fluid are fixed to the surface fixed to the light emitting element base of the light emitting element. Therefore, since the flow path of the cooling fluid is controlled in the light source device, the cooling liquid flows smoothly and the cooling effect can be enhanced.

In addition, by flowing the cooling liquid, the light emitting element can be efficiently cooled directly or indirectly. For example, heat generated by the light emitting element is quickly conducted to the light emitting element base made of a metal having a higher thermal conductivity than the cooling fluid. At this time, since the light emitting element base is also cooled, the cooling effect can be enhanced. Thus, in order to obtain the same cooling effect, the flow rate of the cooling fluid can be reduced, so that the cooling structure of the light source device can be simplified and the size can be reduced.
Thus, since the flow rate of the cooling fluid can be reduced, the pressure of the cooling fluid can be reduced. As a result, for example, the stress applied to the light emitting element itself or the connection portion that electrically connects the light emitting element and the external control circuit can be reduced, so that the performance of the light source device can be maintained over a long period of time.

  In the present invention, the light-emitting element is immersed in the cooling fluid, and two pairs of the inflow path and the outflow path are provided at positions facing each other across the light-emitting element in a planar direction, and each is substantially parallel. And the inflow path and the outflow path are provided adjacent to each other, and the perpendicular distance from the outflow path with respect to the light emitting element is provided at a position separated from the perpendicular distance from the inflow path. It is preferable.

According to the present invention, since the inflow path and the outflow path of the cooling fluid are provided to face each other with the light emitting element interposed therebetween, the cooling fluid flows and is discharged smoothly while cooling the light emitting element. The inflow path and the outflow path are arranged adjacent to each other, and the cooling fluid flows around the light emitting element and is discharged from the outflow path adjacent to the inflow path. Circulation is performed smoothly.
Furthermore, since the outflow path is arranged at a distance away from the light emitting element than the inflow path, for example, when the shape of the light-emitting element base in which the cooling fluid flows is circular, The intersection part inside the outflow outlet of the passage forms a sharper corner than the other intersection, so that the cooling fluid is directly discharged from the outflow passage by this corner, and the light emitting element Is divided into a flow that rotates and flows along the circumference of the.

By controlling the flow direction of the cooling fluid in this way, the cooling fluid flows smoothly along the light emitting element, so that the light emitting element can be efficiently cooled. This also makes the temperature distribution of the light-emitting element uniform, making it difficult for thermal stress to occur, preventing the light-emitting element from being distorted, broken, and sliding, and preventing deterioration of the light-emitting element due to thermal stress. can do.
In addition, the cooling fluid is flowed by, for example, an external pump, etc., but the cooling fluid can be smoothly flowed so that the flow rate is small in order to obtain the same cooling effect. Can be miniaturized.

  In the present invention, the light emitting element is immersed in the cooling fluid, and a pair of the inflow path and the outflow path are provided at positions facing each other across the light emitting element in the planar direction, and each is arranged in parallel. In addition, it is preferable that the light emitting element is provided at a position where a perpendicular direction distance from the outflow path is separated from a perpendicular direction distance from the inflow path.

  According to the present invention, although the cooling effect of the light source device is slightly reduced as compared with the structure in which two pairs of the inflow path and the outflow path are provided, the structure is simplified because the inflow path and the outflow path are a pair. And can be miniaturized.

  In the present invention, the light emitting element is immersed in the cooling fluid, the inflow path and the outflow path are provided to face each other, and the light emitting element faces a straight line connecting the facing inflow paths. It is preferable to be provided at a position where the straight line connecting the outflow paths intersects.

  According to the present invention, the cooling fluid flows in toward the light emitting element, contacts the light emitting element, then is diverted in a right angle direction by the light emitting element, flows along the light emitting element, and is discharged from the outflow path. Since the fluid smoothly flows along the light emitting element, the above-described cooling effect and uniform temperature distribution can be obtained. In addition, by arranging the inflow path and the outflow path in a cross shape rather than the structure in which the outflow path and the inflow path are provided in parallel, the distance between the adjacent inflow path and the outflow path can be set larger. There are also effects that it is easy to manufacture and that it is easy to downsize.

In this invention, it is possible that the said inflow path and the said outflow path are provided with two or more by the cross-sectional direction.
In such an invention, a plurality of the inflow passages and outflow passages described above are also provided in the cross-sectional direction, so that the cooling fluid has a flow rate compared to a structure in which the inflow passages and the outflow passages are provided only in the plane direction. Therefore, the cooling effect and temperature uniformity can be further enhanced.

In the present invention, it is preferable that a flow path for the cooling fluid is formed on a surface of the light emitting element base to which the light emitting element is fixed.
According to the present invention, for example, oblique radial or arc-shaped grooves or protrusions are formed toward the light emitting element in order to smoothly guide the flow direction of the cooling fluid on the light emitting element base. The flow direction of the cooling fluid can be freely controlled. As a result, the fluidity and circulation of the cooling fluid are enhanced, and the cooling effect can be further enhanced.

  The present invention is characterized in that a flow path for the cooling fluid is provided in a peripheral portion of the light emitting element base, and the inflow path and the outflow path that flow through the flow path are provided.

According to the present invention, since the light emitting element base in which heat is conducted from the light emitting element can be cooled, the cooling effect is slightly reduced as compared with the structure in which the light emitting element is directly cooled. Because it is not in direct contact with the cooling fluid, the pressure of the cooling fluid is not applied to the light emitting element, and the change in mechanical, chemical and optical characteristics of the light emitting element related to the intrusion of impurities and the change with time can be reduced. .
Further, for example, when the flow path is formed in a ring shape, the cooling fluid flows so as to rotate along this flow path around the light emitting element base, so that the cooling fluid can flow smoothly. . Accordingly, a small flow rate is required to obtain the same cooling effect, and the light source device including the external pump can be downsized.

  In the present invention, two pairs of the inflow path and the outflow path are provided at positions facing each other across the light emitting element in the planar direction, and each is disposed substantially in parallel, and the inflow path and the outflow path are Are arranged adjacent to each other, and the light emitting element is preferably provided at a position where a perpendicular direction distance from the outflow path is further away than a perpendicular direction distance from the inflow path.

According to this invention, since the inflow path and the outflow path of the cooling fluid are circulated in the flow paths provided opposite to each other with the light emitting element interposed therebetween, the cooling fluid smoothly flows and is discharged. The inflow path and the outflow path are arranged adjacent to each other, and the cooling fluid flows through the flow path of the surrounding light emitting element base to which the light emitting element is fixed, and is discharged from the outflow path adjacent to the inflow path. Therefore, the cooling fluid is smoothly circulated in the light source device.
Furthermore, since the outflow path is arranged at a distance away from the light emitting element than the inflow path, for example, when the shape of the light-emitting element base in which the cooling fluid flows is circular, The intersection part inside the outflow outlet of the passage forms a sharper corner than the other intersection, so that the cooling fluid is directly discharged from the outflow passage by this corner, and the light emitting element It is divided into a flow that flows along the periphery of the base.

By controlling the flow direction of the cooling fluid in this way, the light emitting element base is cooled because the light emitting element is fixed, so that thermal stress is less likely to occur in the light emitting element, and destruction of the light emitting element due to thermal stress is prevented. can do.
In addition, the cooling fluid is flowed by, for example, an external pump, etc., but the cooling fluid can be smoothly flowed so that the flow rate is small in order to obtain the same cooling effect. Can be miniaturized.

  In the present invention, a pair of the inflow path and the outflow path are provided at positions facing each other across the light emitting element in a planar direction, and each of the inflow path and the outflow path is arranged in parallel, A light source device, wherein a distance in a perpendicular direction from a path is provided at a position separated from a distance in a perpendicular direction from the inflow path.

  According to the present invention, although the cooling effect of the light source device is slightly reduced as compared with the structure in which two pairs of the inflow path and the outflow path are provided, only one pair of the inflow path and the outflow path is provided. The structure can be simplified and the size can be reduced.

  In the present invention, the inflow path and the outflow path are provided to face each other, and the light source device includes a straight line connecting the opposing inflow paths and a straight line connecting the opposing outflow paths. It is preferable that they are provided at the crossing positions.

  According to the present invention, the cooling fluid flows in toward the light emitting element base, is divided in two directions by the light emitting element base, flows along the light emitting element base, and is discharged from the outflow path. A cooling effect and a uniform temperature distribution can be obtained. In addition, by arranging the inflow path and the outflow path in a cross shape rather than the structure in which the outflow path and the inflow path are provided in parallel, the distance between the adjacent inflow path and the outflow path can be set larger. There are also effects that it is easy to manufacture and that it is easy to downsize.

In the present invention, it is desirable that a plurality of the inflow paths and the outflow paths are provided in the cross-sectional direction.
In such an invention, a plurality of the inflow passages and outflow passages described above are also provided in the cross-sectional direction, so that the cooling fluid has a flow rate compared to a structure in which the inflow passages and the outflow passages are provided only in the plane direction. Therefore, the cooling effect and temperature uniformity can be further enhanced.

The projector according to the present invention includes the above-described light source device.
Such a projector can increase the luminance because the cooling efficiency of the light source device is high, and since the structure is simple, the projector can be downsized while having high luminance. Further, since the temperature of the light emitting element can be made uniform, deterioration of the light emitting element due to thermal stress can be prevented, and good performance can be maintained over a long period of time.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIGS. 1-12 shows the Example of the light source device of this invention, FIG. 13 shows the Example of the projector of this invention.

1 to 3 show a light source device 10 according to a first embodiment.
FIG. 1 is a plan view illustrating the light source device according to the first embodiment, in which the lens cap 200 and the fixing ring 300 illustrated in FIG. 2 are omitted. FIG. 2 is a sectional view of the first embodiment. FIG. 3 is a plan view showing details of the light emitting element base 120 of the first embodiment. 1 and 2, the light source device 10 includes a light emitting element base 120, an LED chip 100 as a light emitting element fixed to the light emitting element base 120, a fixing ring 300, and a lens cap 200. .

  The LED chip 100 has a substantially square planar shape, and is provided with a p-electrode 101 on the top surface and an n-electrode 102 on the bottom surface, and the bottom surface 122 of the recess formed on the light-emitting element base 120. The central portion is fixed with a conductive material such as silver paste, and the p-electrode is connected to the lead substrate 500 with a wire 110.

  The light emitting element base 120 has a rectangular parallelepiped shape, and has a concave portion with a wide opening and a narrow bottom at the center. The light emitting element base 120 is provided with inflow paths 124 and 126 through which the cooling fluid 400 penetrating from the outer edge to the recess flows and outflow paths 125 and 127. The inflow passages 124 and 126 and the outflow passages 125 and 127 are partially provided at a cross-sectional height where the upper surface of the LED chip 100 described later is desired, and the planar position is formed in a direction along one side of the LED chip 100. Has been.

  In FIG. 2, the inflow paths 124 and 126 and the outflow paths 125 and 127 are formed in parallel, and the outflow paths 125 and 127 have a distance H in the direction perpendicular to the LED chip 100 from the longitudinal direction. The distance from the longitudinal direction 126 to the LED chip 100 is set at a position away from the perpendicular distance h. Intersections 125A and 127A of the outflow passages 125 and 127 and the inclined surface portion 121 of the recess are formed at an acute angle with respect to the other intersections 125B and 127B when the plane is viewed.

  In FIG. 3, the flow path 128 of the windmill-like cooling fluid 400 is formed on the bottom 122 of the light emitting element base 120 toward the LED chip 100. The flow channel 128 is formed in a groove shape or a protrusion shape in the bottom portion 122. The flow guide path 128 may be a windmill shape or a linear radial shape, and is formed in a range from the vicinity of the outer periphery of the bottom portion 122 to the vicinity of the periphery of the LED chip 100, but the cooling fluid 100 is surrounded by the periphery of the LED chip 100. It is preferable to provide a space that can flow so as to rotate along the LED chip 100.

As the light emitting element base 120, an aluminum alloy or a copper alloy having a high thermal conductivity can be used. Hereinafter, a case where an aluminum alloy having a small specific gravity and a light weight is used will be described as an example. The light emitting element base 120 is provided with a mirror finish, a fine uneven finish (irregular reflection finish) or a light reflection layer in order to efficiently reflect the visible light emitted from the LED chip 100 onto the surfaces of the slope portion 121 and the bottom portion 122. The plating to form is given. Although not shown, the light emitting element base 120 is connected to an external control circuit.
On the upper surface of the light emitting element base 120, a fixing ring 300 in which a lead substrate 500 is inserted is tightly fixed.

The lead substrate 500 is a strip-shaped thin plate made of metal, and is arranged in the middle of the inflow path 126 and the outflow path 127. Both ends of the lead board 500 are extended from the fixing ring 300, and one end on the inner side is The LED chip 100 is connected to the p-electrode 101 by a wire 110, and the other end is connected to an external control circuit (not shown).
The lens cap 200 is tightly fixed to the upper surface 123 of the fixing ring 300, and a space in which the cooling fluid 400 flows is formed by the lens cap 200, the fixing ring 300, and the concave portion of the light emitting element base 120.
The LED chip 100 emits light according to a light emission signal from an external control circuit.

Next, the flow of the cooling fluid 400 will be described with reference to FIGS. Although not shown, the inflow passages 124 and 126 are connected to a pump provided outside the light source device 10, and the outflow passages 125 and 127 are connected to a tank in which cooling fluid is stored, and flow outside the light source device 10. In the process, the cooling fluid 400 is cooled and flows into the light source device 10 from the inflow paths 124 and 126.
The cooling fluid 400 that has flowed in from the inflow paths 124 and 126 flows in the concave portion of the light emitting element base 120 in the direction of arrow A, and the inflow path 126 and the outflow path 127, and the inflow path 124 and the outflow path 125 are planar. Therefore, the flow is diverted at the intersections 125A and 127A between the outflow passages 125 and 127 and the slope portion 121, a part is discharged to the outside from the outflow passages 125 and 127, and a part is in the arrow B direction. It flows and is discharged from the outflow passages 125 and 127, and the above-mentioned circulation is performed.

  As described in FIG. 3, when the flow guide path 128 is formed, it flows as indicated by the arrows A and B described above (see FIG. 1) and flows toward the LED chip 100 in the direction of the arrow C. Then, a flow as indicated by an arrow D around the LED chip 100 is performed.

Therefore, according to the first embodiment, the inflow path 124 and the outflow path 125 of the cooling fluid 400 and the inflow path 126 and the outflow path 127 are provided to face each other with the light emitting element interposed therebetween. Since the outflow passages 125 and 127 are on the outer side, the flow is diverted at the corners 125A and 127A of the outflow passages 125 and 127 so that the cooling fluid 400 flows around the LED chip. The cooling fluid flows and is discharged smoothly while cooling the light emitting element.
In addition, the inflow path 125 and the outflow path 126, and the inflow path 124 and the outflow path 127 are arranged adjacent to each other, and the cooling fluid 400 flows around the LED chip 100 to cool, and is adjacent to the inflow path. Since it is discharged from the outflow path, the cooling fluid is smoothly circulated in the light source device 10.

By controlling the flow direction of the cooling fluid in this way, the cooling fluid flows smoothly along the light emitting element, so that the light emitting element can be efficiently cooled. This also makes the temperature distribution of the light emitting element uniform, so that thermal stress is less likely to occur, and deterioration of the light emitting element due to thermal stress can be prevented.
In addition, the cooling fluid is flowed by, for example, an external pump, etc., but the cooling fluid can be smoothly flowed so that the flow rate is small to obtain the same cooling effect, thereby reducing the pump power. Thus, the light source device 10 including the pump can be reduced in size.

Next, Example 2 will be described with reference to FIG.
FIG. 4 is a plan view showing the light source device 10 provided with a pair of inflow path and outflow path. Except for the inflow path and the outflow path, the configuration including the cross-sectional relationship is the same as that of the first embodiment. Will be described. In FIG. 4, the light emitting element base 120 is provided with an inflow path 126 and an outflow path 127. The light-emitting element base 120 has a substantially square planar outer shape, and has a recess having a wide opening and a narrow bottom at the center. The light emitting element base 120 has an inflow path 126 through which a cooling fluid 400 that penetrates from the outer edge to the recess and an outflow path 127 are formed, and the inflow path 126 and the outflow path 127 are partly described later of the LED chip 100. The upper surface is provided at a desired cross-sectional height, and the planar position is formed in a direction along one side of the LED chip 100.

The inflow path 126 and the outflow path 127 are formed in parallel with each other, and the outflow path 127 has a perpendicular distance H with respect to the LED chip 100 from the longitudinal direction with respect to the LED chip 100 from the longitudinal direction of the inflow path 126. Is provided at a position away from the distance h in the perpendicular direction. The crossing portion 127A of the outflow passage 127 and the inclined surface portion 121 of the concave portion is formed at an acute angle with respect to the other crossing portion 127B as viewed from the plane.
Further, the flow channel 128 described in the first embodiment is formed on the surface of the bottom 122 (see FIG. 3).

  The cooling fluid 400 flows in from the inflow path 126, flows in the direction of arrow A, is shunted by the corner portion 127 </ b> A, and is rotated along the LED chip 100 in the direction of arrow B and the flow path in which the outflow path 127 is discharged. A flow path is created. Moreover, the flow path of the arrow C direction and the arrow D direction which flow along the flow path 128 is also made (refer FIG. 3).

Therefore, according to the second embodiment, the cooling effect of the light source device 10 is slightly reduced as compared with the structure in which two pairs of the inflow path and the outflow path described in the first embodiment are provided, but almost the same effect. Can be obtained.
Further, since only one inflow path 126 and one outflow path 127 are provided, the structure of the light source device 10 can be simplified and reduced in size.

Next, Example 3 will be described with reference to FIG. The third embodiment has a structure in which the inflow path and the outflow path are opposed to the LED chip 100 based on the technical idea of the first embodiment. The cross-sectional relationship is the same as in FIG.
FIG. 5 is a plan view showing Embodiment 3 of the present invention. In FIG. 5, the LED chip 100 has a substantially square planar shape, is provided with a p-electrode 101 on the upper surface and an n-electrode 102 on the lower surface, and the n-electrode 102 is a recess formed in the light emitting element base 120. The p-electrode is connected to the lead substrate 500 with a wire 110 and is fixed to a substantially central portion of the bottom portion 122 with a conductive material such as silver paste.

The light-emitting element base 120 has a substantially square planar outer shape, and has a recess having a wide opening and a narrow bottom at the center. The light emitting element base 120 is provided with inflow paths 124 and 126 through which the cooling fluid 400 penetrating from the outer edge to the recess flows and outflow paths 125 and 127. The inflow passages 124 and 126 and the outflow passages 125 and 127 are provided at a cross-sectional height where the upper surface of the LED chip 100 is desired, and the planar positions are the inflow passages 124 and 126 and the outflow passage toward the corner of the LED chip 100. 125 and 127 are formed to face each other.
The surface of the bottom 122 is preferably provided with a grooved or projecting cooling fluid 400 flow path as in the first embodiment. At this time, the flow path is in the direction of arrow E in the figure. Formed along.

Also in the present embodiment, a tank for storing the cooling fluid 400 and a pump for flowing are provided outside the light source device 10, but the description is omitted because it is the same as the configuration described in the first embodiment. To do.
The cooling fluid 400 that has flowed in from the inflow paths 124 and 126 flows toward the corner of the LED chip 100 and is divided into two directions at this corner (arrow E in the figure), along the side of the LED chip 100. And is discharged to the outflow passages 125 and 127.

  Therefore, according to the third embodiment, the cooling fluid 400 flows in toward the corner portion of the LED chip 100, is divided into two directions at the corner portion, flows along the side of the LED chip 100, and flows from the outflow path. Since it is discharged, the same cooling effect and uniform temperature distribution as in the first embodiment can be obtained. Further, the inflow paths 124 and 126 and the outflow paths 125 and 127 are adjacent to each other by arranging them in a cross shape rather than the structure in which the outflow paths 124 and 126 and the inflow paths 125 and 127 of Example 1 are provided in parallel. The distance between the inflow passage 124 and the outflow passages 125 and 127, and the distance between the inflow passage 124 and the outflow passages 125 and 127 can be set large, and there is an effect that it is easy to manufacture and that it is easy to downsize.

  Although not shown, a structure including only one pair of the outflow path and the inflow path can be considered from the configuration of the third embodiment. In this case, for example, the outflow path 127 can be provided at a position facing the inflow path 126 (the outflow path 127 is provided at the position of the inflow path 124 shown in FIG. 5).

In such a structure, the cooling effect of the light source device 10 is slightly reduced as compared with the case where two pairs of the inflow path and the outflow path shown in the third embodiment are provided, but almost the same effect can be obtained.
Further, since only one inflow path 126 and one outflow path 127 are provided, the structure of the light source device 10 can be simplified and reduced in size.

  Next, Example 4 will be described with reference to FIG. The fourth embodiment shows the light source device 10 provided with a plurality of inflow paths 124 and 126 and outflow paths 125 and 127 shown in the first to third embodiments in the cross-sectional direction. Except for the layout in the cross-sectional direction of the inflow path and the outflow path, the description is omitted because it is the same as the first embodiment. In FIG. 6, inflow paths 131 and 133 are provided above the inflow paths 124 and 126 provided in the light emitting element base 120. Outflow passages 132 and 134 are also provided above the outflow passages 125 and 127.

Here, the inflow paths 131 and 133 and the outflow paths 132 and 134 have substantially the same planar positions as those in the first embodiment (see FIG. 1), and the inflow and outflow directions of the cooling fluid 400 are the same. The inflow channels 131 and 133 and the outflow channels 132 and 134 may be disposed at positions rotated 90 degrees in the plane direction with respect to the inflow channels 124 and 126 and the outflow channels 125 and 127. The inflow channels 131 and 133 and the outflow channels 132 and 134 may be rotated 90 degrees in the plane direction with respect to the inflow channels 124 and 126 and the outflow channels 125 and 127 shown in FIG.
Also, a flow path 128 for the cooling fluid 400 as shown in FIG. 3 may be provided.

  Furthermore, as described above, the inflow channels 131 and 133 are arranged so that the inflow channels 124 and 126 in the lower stage and the outflow channels 132 and 134 and the outflow paths 125 and 127 in the lower stage overlap in the planar direction. Each can be switched between inflow and outflow. That is, the inflow paths 131 and 133 can be used as outflow paths, and the outflow paths 132 and 134 can be used as inflow paths.

Therefore, according to the fourth embodiment, in addition to the inflow channels 124 and 126 and the outflow channels 125 and 127, the inflow channels 131 and 133 and the outflow channels 132 and 134 are provided with steps in the cross-sectional direction. Since the cooling fluid 400 can increase the flow rate as compared with the structure in which the inflow path and the outflow path are provided only in one plane direction, the cooling effect and temperature uniformity can be further enhanced.
Moreover, even when a pair of inflow passages and outflow passages are provided as in the modification example of Embodiment 2 and Embodiment 3, the upper inflow passage and outflow passage, the lower inflow passage and outflow passage, The plane direction angle can be arbitrarily shifted.

  In addition, in Example 1- Example 4, although the external shape of the light emitting element base 120 is a rectangular parallelepiped, it can also be made into the columnar shape whose outer periphery is circular.

Next, Example 5 will be described with reference to FIGS.
FIG. 7 is a plan view showing the light source device 10 according to the fifth embodiment of the present invention, in which the fixing ring 300 and the lens cap 200 are omitted. FIG. 8 is a cross-sectional view illustrating the light source device 10 according to the fifth embodiment. 7 and 8, the LED chip 100 has a substantially square planar shape, is provided with a p-electrode 101 and an n-electrode 102 on the upper surface, and a bottom surface of a recess formed on the light-emitting element base 120 on the lower surface. It is fixed to the substantially central portion of 122 with an adhesive or the like. The p electrode 101 and the n electrode 102 are connected to lead substrates 501 and 502 by wires 110, respectively.

  The light emitting element base 120 has a cylindrical outer shape, a recess having a wide opening at the center and a narrow bottom is formed, and a flow path 129 of a ring-shaped cooling fluid 400 is formed at the outer edge. . The channel 129 has a bottom formed deeper than the surface of the bottom 122 of the light emitting element base 120 and an upper portion opened. Inflow passages 124 and 126 and outflow passages 125 and 127 penetrating the flow passage 129 and the light emitting element base 120 from the outer peripheral portion are formed.

The inflow channels 124 and 126 and the outflow channels 125 and 127 are formed in parallel, and the outflow channels 125 and 127 have a perpendicular distance H from the longitudinal direction with respect to the LED chip 100, and the longitudinal directions of the inflow channels 124 and 126. The LED chip 100 is provided at a position away from the distance h in the direction perpendicular to the LED chip 100. The crossing portions 125A and 127A in which the outflow passages 125 and 127 cross the flow passage 129 are formed at an acute angle with respect to the other crossing portions 125B and 127B when the plane is viewed.
The upper opening of the channel 129 is fixed to the light emitting element base 120 by means of adhesion or the like by the fixing ring 300 and hermetically sealed.

  In FIG. 8, the fixing ring 300 is formed in a ring shape having two steps in the cross-sectional direction, and the outer periphery is substantially the same shape as the outer periphery of the light emitting element base 120 and is formed of a synthetic resin. . Lead substrates 501 and 502 are insert-molded and fixedly fixed to the fixing ring 300. Both ends of the lead substrates 501 and 502 are exposed, and the inner ends of the lead substrate 501 are connected to the p-electrode 101 of the LED chip 100 and the wires 110. The outer end is connected to an external control circuit (not shown). Further, the inner end portion of the lead substrate 502 is connected to the n-electrode 102 of the LED chip 100 by the wire 101, and the outer end portion is connected to an external control circuit (not shown).

A lens cap 200 is closely fixed to the upper surface of the fixing ring 300, and a space for housing the LED chip 100 is formed by the light emitting element base 120, the fixing ring 300, and the lens cap 200.
The LED chip 100 emits light upon obtaining a light emission signal from an external control circuit.

  The light emitting element base 120 may be made of an aluminum alloy or copper alloy having a high thermal conductivity, but an aluminum alloy that has a small specific gravity and can be reduced in weight is preferably employed. The light emitting element base 120 is provided with a mirror finish, a fine uneven finish (irregular reflection finish) or a light reflection layer in order to efficiently reflect the visible light emitted from the LED chip 100 onto the surfaces of the slope portion 121 and the bottom portion 122. The plating to form is given.

  Further, although not shown, the cooling fluid 400 is connected to a pump provided outside the light source device 10, and the outflow paths 125 and 127 are connected to a tank in which the cooling fluid is stored, and flow outside the light source device 10. In the process, the cooling fluid 400 is cooled and flows into the light source device 10 from the inflow paths 124 and 126.

  The cooling fluid 400 that has flowed in from the inflow paths 124 and 126 flows along the walls of the flow path 129 as indicated by arrows in FIG. 7, and the discharge direction and flow paths at the corners 125A and 127A of the outflow paths 125 and 127. 129 and the direction along 129. In this way, the cooling fluid 400 flows smoothly in the flow path.

Therefore, according to the fifth embodiment, the cooling efficiency is slightly reduced as compared with the structure in which the LED chip 100 described in the first to fourth embodiments is directly cooled by the cooling fluid 400, but the liquid or gas or the like is reduced. A cooling effect can be sufficiently obtained by forcing the cooling fluid to flow the heat transmitted to the light emitting element base 120 having higher thermal conductivity than the cooling fluid 400.
In addition, since the outflow paths 125 and 127 are outside the LED chip 100 with respect to the inflow paths 124 and 126, the intersecting portions 125A and 127A with the flow path 129 are at an acute angle than the other intersecting portions 125B and 127B. Therefore, the cooling fluid is divided by the corner portions 125A and 127A and smoothly flows along the wall in the flow path 129, so that the power of the pump can be reduced. Since the width can be reduced, the light source device including the pump can be downsized.

  Furthermore, since the cooling fluid 400 does not directly contact the LED chip 100, the LED chip 100 is worn by the cooling fluid 400, the characteristics of the LED chip 100 change due to the intrusion of impurities, bubbles that are considered to be generated in the cooling fluid, and the like. Thus, good performance can be maintained over a long period of time.

Although not shown in the figure, in Example 5, two pairs of inflow passages and outflow passages are provided, but a light source device having one pair of inflow passages and outflow passages is also conceivable. That is, the light source device 10 is configured by the inflow path 124 and the outflow path 125 by deleting the inflow path 126 and the outflow path 127 shown in FIG. At this time, it is possible to have only the inflow path 126 and the outflow path 127, and the effect is the same.
In this case, the cooling efficiency is slightly reduced as compared with the structure having two pairs of the inflow path and the outflow path, but the structure can be simplified and the size can be reduced.

Next, Example 6 will be described with reference to FIG. The sixth embodiment has a structure in which the direction of the inflow path and the outflow path is changed with respect to the LED chip 100 as compared with the fifth embodiment, and the other parts are the same as those of the fifth embodiment, and thus the description thereof is omitted.
FIG. 9 is a plan view illustrating the light source device 10 according to the sixth embodiment, in which the fixing ring 300 and the lens cap 200 are omitted.

In FIG. 9, inflow paths 124 and 126 and outflow paths 125 and 127 are arranged so as to face each other with the LED chip 100 interposed therebetween. The inflow channels 124 and 126 and the outflow channels 125 and 127 are formed at positions shifted from each other by 90 degrees. That is, the extension lines of the inflow path and the outflow path are orthogonal to each other.
The cooling fluid 400 is diverted in the directions indicated by the arrows A and B in the drawing at locations where the cooling fluid 400 flows into the flow path 129 from the inflow paths 124 and 126, and is discharged from the outflow paths 125 and 127 at positions rotated by 90 degrees. Since the intersection of the outflow passages 125 and 127 with the flow path 129 is chamfered, the cooling fluid 400 that has flowed along the walls of the flow path 129 is shaped to easily flow out into the outflow paths 125 and 127. ing.

Therefore, in the sixth embodiment, the cooling fluid that has flowed in from the inflow paths 124 and 126 is divided and flows along the wall of the flow path 129, and is discharged from the outflow paths 125 and 127. Since it is smoothly flowed in the road, the same effect as in the fifth embodiment can be obtained.
The inflow paths 124 and 126 and the outflow paths 125 and 127 are formed at right angles to the outer edge side surface of the light emitting element base and the flow path 129, and the distance between the inflow paths 124 and 126 and the outflow paths 125 and 127. Since they are separated, the cost can be reduced because they are easily processed.

In addition, in Example 6 mentioned above, although two pairs of an inflow path and an outflow path are provided, although not shown in figure, an inflow path and an outflow path can also be comprised by 1 pair. That is, the outflow passages 125 and 127 shown in FIG. 9 are deleted and the inflow passage 126 is used as the outflow passage. Accordingly, the outflow path 126 is provided on the extension line of the inflow path 124, and the cooling fluid 400 flows in from the inflow path 124, is divided in two directions, and rotates about 180 degrees along the wall in the flow path 129. And discharged from the outflow channel.
In such a structure, the cooling efficiency is slightly reduced as compared with the structure having two pairs of the inflow path and the outflow path, but the structure can be simplified and the size can be reduced.

Next, Example 7 of the present invention will be described with reference to FIG. Example 7 is a structure provided with a plurality of inflow paths and outflow paths by providing a step in the cross-sectional direction in addition to the inflow path and outflow path described in Example 5 and Example 6, and other structures are implemented. Since it is the same as Example 5 and Example 6, it abbreviate | omits.
FIG. 10 is a cross-sectional view illustrating the light source device 10 according to the seventh embodiment. In FIG. 10, the light emitting element base 120 includes inflow paths 124 and 126 and outflow paths 125 and 127 penetrating from the side surface of the outer edge portion to the flow path 129, and the inflow paths 132 and 134 and the outflow path 131 are provided in the lower part in the cross-sectional direction. , 133 are provided.
The inflow channels 132 and 134 and the outflow channels 131 and 133 are arranged so as to overlap with each other in plan view of the inflow channels 124 and 126 and the outflow channels 125 and 127.

  Therefore, according to the seventh embodiment, since the inflow passage and the outflow passage are configured in four pairs, in addition to the effects of the fifth and sixth embodiments, the flow rate of the cooling fluid 400 can be increased. The cooling effect can be further enhanced.

  In addition, although this Example 7 is applicable also to the modification of above-mentioned Example 5 and Example 6, although not shown in figure, the flow path of an upper and lower inflow path and an outflow path can be changed. For example, in the fifth embodiment (see FIG. 7), the inflow paths 132 and 133 provided in the lower part of the inflow paths 124 and 126 and the outflow paths 125 and 127 are used as the outflow paths of the cooling fluid 400, and the outflow paths 131 and 133 can be an inflow path.

  As a result, different flow layers of the cooling fluid 400 are formed in the upper layer and the lower layer in the flow path 129. Accordingly, since the cooling fluid 400 is stirred at the interface of the fluidized bed, the fluidity is slightly reduced, but the temperature uniformity can be improved.

Further, the upper inflow channel and the outflow channel and the lower inflow channel and the outflow channel can be formed by shifting the phase by 45 degrees to 90 degrees in the plane direction.
Such a combination can be freely selected and combined based on the size of the light source device 10 and the performance of a projector equipped with the light source device 10 described later.

Next, an eighth embodiment of the present invention will be described with reference to FIG.
FIG. 11 is a cross-sectional view showing the eighth embodiment. In FIG. 11, in addition to the inflow paths 124 and 126 and the outflow paths 125 and 127 shown in the fifth and sixth embodiments, the light emitting element base 120 is provided below the lower portion 122 of the concave portion of the light emitting element base 120. A flow path 135 of the cooling fluid 400 penetrating from the outer periphery of the light emitting element base 120 is formed.
The size of the flow path 135 is not particularly limited, but is larger than the planar size of the LED chip 100, and preferably equal to the planar size of the lower portion 122 of the light emitting element base 120.

  The eighth embodiment can also be applied to the first to seventh embodiments, and the LED chip 100 can be indirectly cooled in the vicinity of the lower portion of the LED chip 100 that is a heat generation source. In addition to the effects described in Example 7, a further cooling effect can be obtained.

Next, Embodiment 9 of the present invention will be described with reference to FIG. The ninth embodiment has a structure in which the cooling fin 136 is provided in the flow path 129 of the above-described fifth to eighth embodiments.
FIG. 12 is a cross-sectional view showing the ninth embodiment. In FIG. 12, cooling fins 136 having an uneven cross section are provided on a wall portion of the ring-shaped flow path 129 provided on the light emitting element base 120 near the LED chip 100. The cooling fin 136 may be provided at the bottom of the flow path 129. In addition, cooling fins can be provided on the outer periphery of the light emitting element base 120.

  Therefore, by providing cooling fins on the walls in the flow path 129 and causing the cooling fluid 400 to flow, the heat dissipation effect is enhanced, and in addition to the effects described in the fifth to eighth embodiments, a further cooling effect is obtained. be able to.

Next, a projector equipped with the light source device 10 described in the first to ninth embodiments will be described with reference to FIG.
FIG. 13 is a schematic configuration diagram showing the configuration of the projector 1000 of the present invention. In FIG. 13, the projector 1000 according to the present invention faces each of the three light source devices 10R, 10G, and 10B that emit red light (R), green light (G), and blue light (B), respectively. The arranged light valves 800R, 800G, and 800B, the dichroic prism 700 (color combining optical system) that synthesizes and emits the modulated lights emitted from the three light valves 800R, 800G, and 800B, and the dichroic prism 700 A projection lens 600 (projection optical system) that magnifies and projects the combined light emitted from the projector.

  The light source devices 10R, 10G, and 10B are provided with the cooling means described in the first to ninth embodiments of the present invention. Although not shown, these light source devices 10R, 10G, and 10B include a tank that stores the cooling fluid 400 outside and a pump that flows the cooling fluid.

  Therefore, in the projector 1000 to which the present invention is applied, the color lights R, G, and B emitted from the light source devices 10R, 10G, and 10B are incident on the corresponding light valves 800R, 800G, and 800B, and then the light valves 800R and 800G. , 800B and then emitted toward the dichroic prism 700. The light components R, G, and B corresponding to the three primary colors modulated by the light valves 800R, 800G, and 800B are combined by the dichroic prism 700, and then enlarged as a color image on the screen 900 via the projection lens 600. Projected.

  Therefore, according to the tenth embodiment of the present invention, since the light source device 10 has high cooling efficiency of the LED chip 100, the luminance can be increased and the structure is simple, so the light source device 10 is mounted. The projector 1000 can also be downsized with high brightness and can maintain good performance over a long period of time.

In addition, this invention is not limited to the above-mentioned Example, The deformation | transformation in the range which can achieve the objective of this invention, improvement, etc. are included in this invention.
For example, in Example 1 to Example 9, the LED chip 100 has a substantially square planar shape, but the same effect can be obtained even if the planar shape is circular. In Examples 1 to 5, the LED chip is provided with the p-electrode 101 on the upper surface side and the n-electrode 102 on the lower surface side, and in Examples 5 to 9, the p-electrode 101 and the n electrode are provided on the upper surface side. Although the electrodes 102 are provided side by side, the LED chip 100 does not change the effect obtained by adopting either structure.
In the present invention, even when the p electrode 101 and the n electrode 102 are provided on the lower surface of the LED chip 100, an insulating layer is formed on the fixing surface 122 of the LED chip 100 of the light emitting element base 120, and the upper surface of the insulating layer is formed. The present invention can also be applied to a structure in which electrodes corresponding to the p-electrode 101 and the n-electrode 102 are formed.

In the first to ninth embodiments, one LED chip 100 is used in the light source device 10, but a plurality of LED chips 100 can be installed.
Further, in the projector 1000 of the present invention, one light source device 10R, 10G, 10B is installed for each color light in the tenth embodiment, but a plurality of light source devices may be installed for each color light. good.

  Therefore, according to the present invention, the light source device 10 in which the cooling effect is enhanced by forcibly flowing the cooling fluid 400 directly or indirectly through the LED chip 100, and the light source device 10 is mounted, and the brightness is high and good. Thus, it is possible to provide a projector 1000 that can maintain a satisfactory performance over a long period of time.

The top view which shows the light source device concerning Example 1 of this invention. Sectional drawing which shows the light source device concerning Example 1 of this invention. The principal part top view which shows the light source device concerning Example 1 of this invention. The top view which shows the light source device concerning Example 2 of this invention. The top view which shows the light source device concerning Example 3 of this invention. Sectional drawing which shows the light source device concerning Example 4 of this invention. The top view which shows the light source device concerning Example 5 of this invention. Sectional drawing which shows the light source device concerning Example 5 of this invention. The top view which shows the light source device concerning Example 6 of this invention. Sectional drawing which shows the light source device concerning Example 7 of this invention. Sectional drawing which shows the light source device concerning Example 8 of this invention. Sectional drawing which shows the light source device concerning Example 9 of this invention. FIG. 10 is a configuration diagram illustrating a projector according to a tenth embodiment of the invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Light source device, 100 ... LED chip, 120 ... Light emitting element base, 124, 126, 132, 134 ... Inflow path, 125, 127, 131, 133 ... Outflow path, 400 ... Cooling fluid, 1000 ... Projector.

Claims (8)

A light source device in which a light emitting element is cooled by a cooling fluid,
A light emitting element base to which the light emitting element is fixed;
The light emitting element base is provided with an inflow path of the cooling fluid and an outflow path,
The inflow path and the outflow path are provided substantially parallel to the surface of the light emitting element base to which the light emitting element is fixed,
The inflow path and the outflow path are provided to face each other,
The light source device is provided at a position where a straight line connecting the opposing inflow passages and a straight line connecting the opposing outflow passages intersect each other. A light source device in which a light emitting element is cooled by a cooling fluid,
A light emitting element base to which the light emitting element is fixed;
The light emitting element base is provided with an inflow path of the cooling fluid and an outflow path,
The inflow path and the outflow path are provided substantially parallel to the surface of the light emitting element base to which the light emitting element is fixed,
The inflow path and the outflow path are provided at positions facing each other across the light emitting element in a planar direction, and each is disposed in parallel.
The light source device, wherein the light emitting device is provided with a perpendicular distance from the outflow path in a plane direction with respect to the light emitting element at a position separated from the perpendicular distance from the inflow path. The light source device according to claim 2,
A pair of the inflow path and the outflow path is provided. The light source device according to claim 2,
Two pairs of the inflow path and the outflow path are provided,
The light source device, wherein the inflow path and the outflow path are provided adjacent to each other. The light source device according to any one of claims 1 to 4,
The cooling fluid flow path is provided at the peripheral edge of the light emitting element base,
A light source device comprising the inflow path and the outflow path that circulate in the flow path. The light source device according to any one of claims 1 to 4,
The light source device, wherein the light emitting element is immersed in the cooling fluid. The light source device according to claim 6,
A light source device, wherein a flow path for the cooling fluid is formed on a surface of the light emitting element base to which the light emitting element is fixed. The light source device according to any one of claims 1 to 7,
A light source device comprising a plurality of inflow paths and outflow paths in a cross-sectional direction substantially perpendicular to a planar direction.

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