JP2008226570A - Light source device and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device capable of further increasing luminance while extending the service life of the light source device itself. <P>SOLUTION: This light source device 110 is provided with: an arc tube 20 having a vessel part 30 with a pair of electrodes arranged along an illumination optical axis incorporated therein, and a pair of sealing parts 40 and 50 extending to both sides of the vessel part 30; an ellipsoidal reflector 10 arranged on the sealing part 40 side of the arc tube 20, and reflecting light from the arc tube 20 toward an illumination object region side; and a heat insulation member 70. The heat insulation member 70 has: a vessel covering part 72 covering at least a region including a top part 34 on the lower side with respect to the gravity on the outer surface of the vessel part 30, and connection parts 36 and 38 between the vessel part 30 and the sealing parts 40 and 50 on the outer surface of the vessel part 30; and support parts 74 and 76 arranged at both ends of the vessel covering part 72 and fixed to the sealing parts 40 and 50. The vessel covering part 72 transmits the light from the arc tube 20. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light source device and a projector.

  2. Description of the Related Art Conventionally, as a light source device used in a projector, an arc tube having a tube bulb portion including a pair of electrodes, a pair of sealing portions extending on both sides of the tube bulb portion, and one of the arc tube are disposed on one sealing portion side. There is known a light source device including a reflector that reflects light from an arc tube toward an illuminated region (see, for example, Patent Document 1).

JP 2005-5183 A

  By the way, in the conventional light source device, the temperature of the upper apex portion with respect to the gravity in the bulb portion tends to be particularly high due to thermal convection, and the temperature exceeds the allowable temperature of the base material constituting the bulb portion. In some cases, local swelling or whitening may occur in the upper apex portion of the tube portion. Whitening is a phenomenon in which the base material constituting the tube portion becomes clouded and devitrified. When local swelling occurs in the bulb portion, the arc tube may rupture due to a decrease in strength. Further, when the tube bulb portion is whitened, light transmission is hindered at the whitened portion, and as a result, heat is generated and the temperature of the arc tube further rises. As a result, the arc tube may burst. .

  That is, in the conventional light source device, the temperature at the upper apex portion with respect to the gravity at the bulb portion tends to be particularly high due to thermal convection and the like. May cause blistering or whitening. If local swelling occurs or whitens at the upper apex portion of the bulb portion, the lifetime of the light source device is reduced.

  In order to suppress the temperature rise at the upper apex portion of the tube portion, it is conceivable to cool the arc tube with a cooling fan. However, in the conventional light source device, the temperature of the upper apex portion in the bulb portion and the coldest portion in the bulb portion (the lower apex portion in the bulb portion or the connection portion between the bulb portion and the sealing portion ( Because the temperature difference from the temperature of the electrode part in the tube part)) is large, when the temperature of the upper apex part in the tube part is cooled below a predetermined temperature, the coldest part in the tube part is more than necessary. May be cooled, and the coldest part in the tube part may be blackened. Blackening is a phenomenon in which the inclusion (eg, mercury, rare gas, metal halide, etc.) enclosed in the tube part adheres to the inner wall of the tube part. When the tube portion is blackened in this way, light is absorbed at the blackened portion, which may reduce the light amount of the arc tube or damage the arc tube.

  Thus, in the conventional light source device, the temperature of the upper apex portion in the bulb portion is likely to be high, and the temperature between the temperature of the upper apex portion in the bulb portion and the temperature of the coldest portion in the bulb portion. Due to the large difference, there is a problem that it is not easy to extend the life of the light source device. Further, there is a problem that it is not easy to further increase the luminance of the light source device.

  Accordingly, the present invention has been made to solve the above-described problem, and an object of the present invention is to provide a light source device capable of further increasing the brightness while extending the life of the light source device. It is another object of the present invention to provide a projector including such an excellent light source device.

  The light source device of the present invention includes a light emitting tube having a tube portion containing a pair of electrodes arranged along an illumination optical axis, a pair of sealing portions extending on both sides of the tube portion, and one of the light emitting tubes. A reflector that is disposed on the sealing portion side and reflects light from the arc tube toward the illuminated region side, and a region that includes at least a vertex portion below the gravity on the outer surface of the tube portion, and A tube bulb covering portion covering an area including a connection portion between the tube bulb portion and the sealing portion on the outer surface of the tube bulb portion, and disposed at both ends of the tube bulb covering portion and fixed to the pair of seal portions. And a heat insulating member having a support portion, wherein the tube covering portion transmits light from the arc tube.

  For this reason, according to the light source device of the present invention, at least a region including a lower apex portion with respect to gravity on the outer surface of the tube portion, and a connection portion between the tube portion and the sealing portion on the outer surface of the tube portion Therefore, when the arc tube is cooled with a cooling fan, the coldest part of the tube bulb can be kept warm. This makes it possible to reduce the temperature difference between the temperature of the upper apex portion in the tube portion and the temperature of the coldest portion in the tube portion. Even if it is a case where it cools to below, it becomes possible to suppress that the coldest part in a bulb part will be cooled more than necessary. As a result, it is possible to suppress a decrease in the light amount of the arc tube and damage to the arc tube due to blackening.

  In addition, according to the light source device of the present invention, it is possible to reduce the temperature difference between the temperature of the upper apex portion in the bulb portion and the temperature of the coldest portion in the bulb portion, so that the arc tube is cooled. By cooling with a fan, it is possible to suppress the temperature rise of the upper apex portion in the tube portion. As a result, it is possible to suppress the occurrence of local swelling or whitening at the upper apex portion of the bulb portion, and it is possible to suppress a decrease in the lifetime of the light source device.

  Therefore, the light source device of the present invention is a light source device capable of further increasing the luminance while extending the life of the light source device.

  In the light source device according to the aspect of the invention, it is preferable that the tube covering portion has a shape that covers a lower half of the outer surface of the tube portion with respect to gravity.

  By configuring in this way, the heat retention effect of the coldest part in the tube part can be increased, and the temperature difference between the temperature of the upper apex part in the tube part and the temperature of the coldest part in the tube part is obtained. It can be further reduced. As a result, it is possible to further suppress the occurrence of a decrease in the light amount of the arc tube and damage to the arc tube due to blackening.

  In the light source device of the present invention, it is preferable that the heat retaining member is made of quartz glass.

  Since quartz glass is excellent in heat resistance and light transmittance, it can be suitably used as a heat retaining member.

  In the light source device of the present invention, it is preferable that an antireflection film is provided on the surface of the heat retaining member.

  By comprising in this way, the reflection loss of visible light at the time of passing the surface of a heat retention member can be suppressed, and it becomes possible to improve light utilization efficiency.

  In the light source device of the present invention, the reflector has a reflective concave surface that reflects light from the arc tube toward the illuminated area, and the reflective concave surface allows light passing through the tube covering portion to When refracting on the surface of the tube covering portion, it is preferable to have a curved shape that reflects and corrects the refraction.

  With this configuration, the light that has passed through the tube cover is also directed toward the subsequent optical element, as is the light that does not pass through the tube cover (light emitted from the upper side of the tube). It becomes possible to reflect correctly. For example, when the reflector is an ellipsoidal reflector, light that has passed through the tube covering portion can be reflected toward the second focal position of the ellipsoidal reflector. Further, when the reflector is a parabolic reflector, the light that has passed through the tube covering portion can be reflected toward the illuminated region as light substantially parallel to the illumination optical axis.

  In the light source device of the present invention, the light emitting device is disposed on the other sealing portion side of the arc tube so as to cover the outer surface of the bulb portion on the illuminated area side, and directs light from the arc tube toward the arc tube. It is preferable to further include a reflecting means for reflecting.

By the way, it is possible to improve the light utilization efficiency and to reduce the size of the reflector by disposing the reflecting means in the sealing portion of the arc tube, thereby realizing a high-luminance and compact light source device. However, since almost half of the bulb portion is covered by the reflecting means, the light source device in which the reflecting means is disposed in the sealing portion of the arc tube has such a reflecting means. There is a tendency that the temperature of the bulb portion tends to be higher than that of the light source device that is not used.
As described above, the present invention cools the upper apex portion of the tube portion while keeping the coldest portion of the tube portion, and suppresses the overall temperature of the tube portion from increasing. Therefore, the effect is particularly great for the light source device in which the reflection means is disposed in the sealing portion of the arc tube as described above.

  A projector according to the present invention includes a light source device according to the present invention, an electro-optic modulation device that modulates an illumination light beam from the light source device according to image information, and a projection optical system that projects light modulated by the electro-optic modulation device. It is characterized by providing.

  For this reason, according to the projector of the present invention, since the above-described excellent light source device is provided, the projector has a long-life light source device and a high brightness.

  In the projector according to the aspect of the invention, it is preferable that the projector further includes a cooling mechanism for cooling the light source device.

  With this configuration, it is possible to suppress the temperature rise of the light source device, and it is possible to further increase the luminance while extending the life of the light source device.

  Hereinafter, a light source device and a projector according to the present invention will be described based on embodiments shown in the drawings.

[Embodiment 1]
FIG. 1 is a diagram illustrating an optical system of a projector 1000 according to the first embodiment. FIG. 2 is a diagram for explaining the light source device 110 according to the first embodiment. 2A is a side view of the light source device 110, and FIG. 2B is an enlarged view of the peripheral portion of the tube portion 30. FIG. 3 is a view for explaining the heat retaining member 70. FIG. 3A is a perspective view showing a peripheral portion of the tube portion 30, and FIG. 3B is a side view showing the peripheral portion of the tube portion 30. 1 and 2, the secondary mirror 60 and the heat retaining member 70 are shown in a cross section when cut along a plane including the illumination optical axis OC. Further, in FIG. 3, the heat retaining member 70 is shown translucent in order to facilitate understanding of the structures of the sub mirror 60 and the heat retaining member 70.

In the following description, three directions orthogonal to each other are defined as a z-axis direction (illumination optical axis OC direction in FIG. 1), an x-axis direction (a direction parallel to the paper surface in FIG. 1 and perpendicular to the z-axis), and y. Let it be an axial direction (a direction perpendicular to the paper surface in FIG. 1 and perpendicular to the z-axis).
Further, in the following description, the case where projector 1000 is arranged in a so-called stationary state is exemplarily shown, and therefore the direction of gravity is the lower direction (for example, the y (−) direction in FIG. 2A). It becomes.

  As shown in FIG. 1, the projector 1000 according to the first embodiment separates the illumination device 100 and the illumination light flux from the illumination device 100 into three color lights of red light, green light, and blue light and guides them to the illumination area. The three color liquid crystal devices 400R, 400G, and 400B as electro-optic modulation devices that modulate the light-separated color separation light guide optical system 200 and the three color lights separated by the color separation light guide optical system 200 according to image information. A cross dichroic prism 500 that combines the color lights modulated by the three liquid crystal devices 400R, 400G, and 400B; a projection optical system 600 that projects the light combined by the cross dichroic prism 500 onto a projection surface such as a screen SCR; The projector includes a cooling mechanism 700 (not shown).

  The illuminating device 100 includes a light source device 110 that emits an illumination light beam toward the illuminated region, a concave lens 90 that emits the focused light from the light source device 110 as substantially parallel light, and a plurality of portions of the illumination light beam emitted from the concave lens 90. A first lens array 120 having a plurality of first small lenses 122 for dividing the light beam, and a second lens having a plurality of second small lenses 132 corresponding to the plurality of first small lenses 122 of the first lens array 120. The array 130, the polarization conversion element 140 that converts each partial light beam from the second lens array 130 into approximately one type of linearly polarized light having the same polarization direction and emits it, and each partial light beam emitted from the polarization conversion element 140 And a superimposing lens 150 for superimposing in the illuminated area.

  As shown in FIGS. 1 and 2A, the light source device 110 includes an ellipsoidal reflector 10 as a reflector, an arc tube 20 having a light emission center near the first focal point of the ellipsoidal reflector 10, and a reflecting means. A secondary mirror 60 and a heat retaining member 70 are provided. The light source device 110 emits a light beam having the illumination optical axis OC as a central axis.

  As shown in FIG. 2, the arc tube 20 includes a tube bulb portion 30 including a pair of electrodes 42 and 52 arranged along the illumination optical axis OC, and a pair of sealing portions extending on both sides of the tube bulb portion 30. 40, 50, a pair of metal foils 44, 54 sealed in the pair of sealing portions 40, 50, respectively, and a pair of lead wires 46, electrically connected to the pair of metal foils 44, 54, respectively. 56.

If the conditions of the constituent elements of the arc tube 20 are exemplarily shown, the tube portion 30 and the sealing portions 40 and 50 are made of, for example, quartz glass, and mercury or a rare gas is contained in the tube portion 30. And a small amount of halogen is enclosed. The electrodes 42 and 52 are, for example, tungsten electrodes, and the metal foils 44, 54 are, for example, molybdenum foils. The lead wires 46 and 56 are made of, for example, molybdenum or tungsten.
Further, as the arc tube 20, various arc tubes that emit light with high luminance can be employed, for example, a high pressure mercury lamp, an ultra high pressure mercury lamp, a metal halide lamp, or the like.

  The coldest part of the tube part 30 is the lower apex part 34 of the tube part 30 or the connection parts 36 and 38 between the tube part 30 and the sealing parts 40 and 50 (the electrode 42 in the tube part 30). , 52).

  As shown in FIG. 2A, the ellipsoidal reflector 10 is radiated from the arc tube 20 and the opening 12 for inserting and fixing the seal portion (one seal portion) 40 of the arc tube 20. And a reflective concave surface that reflects light toward the second focal position. The ellipsoidal reflector 10 is fixed to the sealing portion 40 of the arc tube 20 with an inorganic adhesive C such as cement filled in the opening 12 of the ellipsoidal reflector 10.

  The reflective concave surface 14 has a curved surface shape such that when light passing through the tube covering portion 72 is refracted on the surface of the tube covering portion 72, the reflection is corrected and reflected.

For example, crystallized glass, alumina (Al ₂ O ₃ ), or the like can be suitably used as the material for the base material constituting the reflective concave surface 14. On the inner surface of the reflective concave surface 14, for example, a visible light reflecting layer made of a dielectric multilayer film of titanium oxide (TiO ₂ ) and silicon oxide (SiO ₂ ) is formed.

  The secondary mirror 60 is a reflecting means that covers substantially half of the bulb portion 30 and is disposed to face the reflective concave surface 14 of the elliptical reflector 10. The secondary mirror 60 is a sealing portion (the other sealing portion) 50 of the arc tube 20. And a reflective concave surface 64 that reflects the light emitted from the arc tube 20 toward the illuminated area toward the arc tube 20. The light reflected by the secondary mirror 60 passes through the arc tube 20 and enters the ellipsoidal reflector 10. The secondary mirror 60 is fixed to the sealing portion 50 of the arc tube 20 with an inorganic adhesive C such as cement filled in the opening 62 of the secondary mirror 60.

As a material constituting the reflective concave surface 64, for example, translucent alumina is used. Thereby, the heat dissipation in the secondary mirror 60 can be improved. In addition to alumina, materials such as quartz glass, sapphire, and ruby may be used.
On the inner surface of the reflective concave surface 64, for example, a reflective layer made of a dielectric multilayer film of tantalum oxide (Ta ₂ O ₅ ) and silicon oxide (SiO ₂ ) is formed.

  The heat retaining member 70 includes a tube cover 72 and support portions 74 and 76 disposed at both ends of the tube cover 72. The heat retaining member 70 is made of, for example, quartz glass.

  As shown in FIGS. 2 and 3, the tube covering portion 72 has a lower half of the outer surface of the tube portion 30 with respect to gravity (with a virtual plane including the illumination optical axis OC and the x axis as a boundary surface). It has a shape that covers the outer surface of the lower half of the virtual plane). Specifically, as shown in FIGS. 2 (b) and 3 (b), an area including the apex portion 34 below the gravity on the outer surface of the tube portion 30, and an outer surface of the tube portion 30. A shape covering the region including the connection portion 36 between the tube bulb 30 and the sealing portion 40 and the region including the connection portion 38 between the tube bulb 30 and the sealing portion 50 on the outer surface of the tube bulb 30. Have. The tube covering portion 72 transmits light from the arc tube 20.

  The support portion 74 is fixed to the sealing portion 40 of the arc tube 20 with an inorganic adhesive C such as cement filled in the inner surface of the support portion 74. The support portion 76 is fixed to the sealing portion 50 of the arc tube 20 with an inorganic adhesive C such as cement filled in the inner surface of the support portion 76.

  In addition, although description by illustration is abbreviate | omitted here, the surface of the heat retention member 70 is provided with the antireflection film.

  As shown in FIG. 1, the concave lens 90 is disposed on the illuminated area side of the ellipsoidal reflector 10. The light from the ellipsoidal reflector 10 is emitted toward the first lens array 120.

  The first lens array 120 has a function as a light beam splitting optical element that splits the light from the concave lens 90 into a plurality of partial light beams, and a plurality of first small lenses 122 are arranged in a plane orthogonal to the illumination optical axis OC. It has a configuration arranged in a matrix of rows and columns. Although not illustrated, the outer shape of the first small lens 122 is similar to the outer shape of the image forming area of the liquid crystal devices 400R, 400G, and 400B.

  The second lens array 130 has a function of forming an image of each first small lens 122 of the first lens array 120 in the vicinity of the image forming area of the liquid crystal devices 400R, 400G, and 400B together with the superimposing lens 150. The second lens array 130 has substantially the same configuration as the first lens array 120, and a plurality of second small lenses 132 are arranged in a matrix of a plurality of rows and a plurality of columns in a plane orthogonal to the illumination optical axis OC. Have a configuration.

The polarization conversion element 140 is a polarization conversion element that emits the polarization direction of each partial light beam divided by the first lens array 120 as approximately one type of linearly polarized light having a uniform polarization direction.
The polarization conversion element 140 transmits one linearly polarized light component among the polarized light components included in the illumination light beam from the light source device 110 and reflects the other linearly polarized light component in a direction perpendicular to the illumination optical axis OC; A reflection layer that reflects the other linearly polarized light component reflected by the polarization separating layer in a direction parallel to the illumination optical axis OC, and a phase difference that converts one linearly polarized light component transmitted through the polarization separating layer into the other linearly polarized light component. And a board.

  The superimposing lens 150 condenses a plurality of partial light beams that have passed through the first lens array 120, the second lens array 130, and the polarization conversion element 140, and superimposes them on the vicinity of the image forming regions of the liquid crystal devices 400R, 400G, and 400B. It is an element. The superimposing lens 150 is arranged so that the optical axis of the superimposing lens 150 and the illumination optical axis OC of the illumination device 100 substantially coincide. The superimposing lens 150 may be composed of a compound lens in which a plurality of lenses are combined.

  The color separation light guide optical system 200 includes dichroic mirrors 210 and 220, reflection mirrors 230, 240 and 250, an incident side lens 260, and a relay lens 270. The color separation light guide optical system 200 separates the illumination light beam emitted from the superimposing lens 150 into three color lights of red light, green light, and blue light, and each of the three color liquid crystal devices 400R to be illuminated. , 400G, 400B.

The liquid crystal devices 400 </ b> R, 400 </ b> G, and 400 </ b> B modulate the illumination light beam according to the image information and are the illumination target of the illumination device 100.
The liquid crystal devices 400R, 400G, and 400B are a pair of transparent glass substrates in which a liquid crystal that is an electro-optical material is hermetically sealed. For example, an incident light that will be described later is used according to given image information using a polysilicon TFT as a switching element. Modulates the polarization direction of one type of linearly polarized light emitted from the side polarizing plate.

  Condensing lenses 300R, 300G, and 300B are disposed in the front stage of the optical path of the liquid crystal devices 400R, 400G, and 400B.

  Although not shown here, incident-side polarizing plates are interposed between the condenser lenses 300R, 300G, and 300B and the liquid crystal devices 400R, 400G, and 400B, and the liquid crystal devices 400R, 400G, and 400B are disposed. Between the 400B and the cross dichroic prism 500, an exit side polarizing plate is interposed. The incident-side polarizing plate, the liquid crystal devices 400R, 400G, and 400B and the exit-side polarizing plate modulate light of each color light incident thereon.

The cross dichroic prism 500 is an optical element that forms a color image by synthesizing an optical image modulated for each color light emitted from the exit side polarizing plate. The cross dichroic prism 500 has a substantially square shape in plan view in which four right-angle prisms are bonded together, and a dielectric multilayer film is formed on a substantially X-shaped interface in which the right-angle prisms are bonded together. The dielectric multilayer film formed at one of the substantially X-shaped interfaces reflects red light, and the dielectric multilayer film formed at the other interface reflects blue light. By these dielectric multilayer films, the red light and the blue light are bent and aligned with the traveling direction of the green light, so that the three color lights are synthesized.

  The color image emitted from the cross dichroic prism 500 is enlarged and projected by the projection optical system 600 to form a large screen image on the screen SCR.

  The projector 1000 is provided with a cooling mechanism 700 (not shown). The cooling mechanism 700 includes at least a cooling fan 710 that cools the light source device 110 and a cooling air flow path 720 that allows cooling air from the cooling fan 710 to pass through (both not shown). The cooling mechanism 700 may be configured to cool not only the light source device 110 but also other optical elements (for example, the liquid crystal devices 400R, 400G, and 400B).

  According to the light source device 110 according to the first embodiment configured as described above, a region including at least the lower apex portion 34 with respect to gravity on the outer surface of the tube portion 30 and a tube on the outer surface of the tube portion 30. Since the region including the connecting portions 36 and 38 between the bulb 30 and the sealing portions 40 and 50 is covered by the bulb covering portion 72, when the arc tube 20 is cooled by the cooling fan 710, the bulb portion 30. It is possible to keep the coldest part (the lower apex part 34 in the bulb part 30 or the connection parts 36, 38 between the bulb part 30 and the sealing parts 40, 50) in the tube part 30. This makes it possible to reduce the temperature difference between the temperature of the upper apex portion 32 in the tube portion 30 and the temperature of the coldest portion in the tube portion 30, and thus the upper apex portion 32 in the tube portion 30. Even when the temperature is cooled to a predetermined temperature or lower, it is possible to prevent the coldest portion of the tube portion 30 from being cooled more than necessary. As a result, it is possible to suppress a decrease in the light amount of the arc tube 20 due to blackening and the occurrence of damage to the arc tube 20.

  Further, according to the light source device 110 according to the first embodiment, it is possible to reduce a temperature difference between the temperature of the upper apex portion 32 in the tube portion 30 and the temperature of the coldest portion in the tube portion 30. Therefore, by cooling the arc tube 20 with the cooling fan 710, it is possible to suppress the temperature rise of the upper apex portion 32 in the bulb portion 30. As a result, it is possible to suppress the occurrence of local bulge or whitening at the upper apex portion 32 in the tube portion 30, and it is possible to suppress a decrease in the lifetime of the light source device 110.

  Therefore, the light source device 110 according to the first embodiment is a light source device capable of further increasing the luminance while extending the life of the light source device.

  In the light source device 110 according to the first embodiment, the tube covering portion 72 has a shape that covers the outer surface of the lower half of the outer surface of the tube portion 30 with respect to gravity. Therefore, the temperature difference between the temperature of the upper apex portion 32 in the tube portion 30 and the temperature of the coldest portion in the tube portion 30 can be further reduced. As a result, it is possible to further suppress the decrease in the light amount of the arc tube 20 due to blackening and the occurrence of breakage of the arc tube 20.

  In the light source device 110 according to the first embodiment, the heat retaining member 70 is made of quartz glass. Since quartz glass is excellent in heat resistance and light transmittance, it can be suitably used as a heat retaining member.

  In the light source device 110 according to the first embodiment, since the surface of the heat retaining member 70 is provided with an antireflection film, the reflection loss of visible light when passing through the surface of the heat retaining member 70 can be suppressed. It is possible to improve the light utilization efficiency.

  In the light source device 110 according to the first embodiment, the reflection concave surface 14 of the elliptical reflector 10 corrects the refraction when light passing through the tube covering portion 72 is refracted on the surface of the tube covering portion 72. Since it has a curved surface shape that reflects, the light that has passed through the tube covering portion 72 is an elliptical surface as well as the light that does not pass through the tube covering portion 72 (light emitted from the upper side in the tube portion 30). Reflection toward the second focal position of the reflector 10 is possible.

In the light source device 110 according to the first embodiment, the light source device 110 is disposed on the other sealing unit 50 side so as to cover the outer surface of the tube portion 30 on the illuminated region side, and directs light from the arc tube 20 toward the arc tube 20. The secondary mirror 60 is further provided as a reflecting means for reflecting light. Thereby, since the light radiated from the arc tube 20 to the illuminated area side is reflected by the secondary mirror 60 toward the ellipsoidal reflector 10, it is radiated from the arc tube 20 to the illuminated area side and is effectively used originally. It is possible to effectively use the light that did not exist. For this reason, the brightness of the light source device 110 can be increased.
Further, it is not necessary to set the size of the ellipsoidal reflector 10 so as to cover the end of the arc tube 20 to be illuminated, and the ellipsoidal reflector 10 can be reduced in size, as a result. A compact light source device can be realized. Furthermore, since the ellipsoidal reflector 10 can be miniaturized, the size of the optical element arranged in the latter stage of the optical path can be reduced, so that a compact projector can be obtained.

By the way, by disposing the secondary mirror 60 in the sealing portion 50 of the arc tube 20, it becomes possible to improve the light utilization efficiency and to reduce the size of the ellipsoidal reflector 10, and to achieve high brightness and compactness. However, since approximately half of the bulb portion 30 is covered by the secondary mirror 60, the light source in which the secondary mirror 60 is disposed in the sealing portion 50 of the arc tube 20. The device 110 tends to have a higher temperature of the tube portion 30 than a light source device in which such a secondary mirror is not provided.
As described above, the present invention cools the upper apex portion 32 of the tube portion 30 while keeping the coldest portion of the tube portion 30, and the temperature of the tube portion 30 becomes higher overall. This is particularly effective for the light source device 110 in which the secondary mirror is disposed in the sealing portion 50 of the arc tube 20 as described above.

  Since the projector 1000 according to the first embodiment includes the excellent light source device 110 described above, the projector 1000 includes a long-life light source device and is a high-brightness projector.

  The projector 1000 according to the first embodiment further includes a cooling mechanism 700 that cools the light source device 110. Therefore, an increase in the temperature of the light source device 110 can be suppressed, and the life of the light source device 110 can be extended and further increased. Brightness can be increased.

[Embodiment 2]
FIG. 4 is a view for explaining the light source device 110 </ b> B according to the second embodiment. FIG. 4A is a side view of the light source device 110 </ b> B, and FIG. 4B is an enlarged view of the peripheral portion of the tube portion 30. FIG. 5 is a view for explaining the heat retaining member 70B. FIG. 5A is a perspective view showing the peripheral portion of the tube portion 30, and FIG. 5B is a side view showing the peripheral portion of the tube portion 30. In FIG. 4, the secondary mirror 60 and the heat retaining member 70 </ b> B are shown in a cross section when cut along a plane including the illumination optical axis OC. Further, in FIG. 5, the heat retaining member 70 </ b> B is illustrated as being translucent in order to facilitate understanding of the structures of the sub mirror 60 and the heat retaining member 70 </ b> B.
4 and 5, the same members as those in FIGS. 2 and 3 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The light source device 110B according to the second embodiment basically has a configuration that is very similar to the light source device 110 according to the first embodiment, but the configuration of the heat retaining member is the same as that of the light source device 110 according to the first embodiment. Different.

  That is, in the light source device 110B according to the second embodiment, as shown in FIGS. 4 and 5, the heat retaining member 70 described in the first embodiment is divided into approximately half and the heat retaining member 70 is further reduced by one size. A heat retaining member 70B having a shape is provided.

  The heat retaining member 70B has a tube covering portion 72B and a support portion 74B disposed at one end of the tube covering portion 72B. The heat retaining member 70B is made of, for example, quartz glass. An antireflection film is provided on the surface of the heat retaining member 70B.

  The tube covering portion 72 </ b> B has a shape that is the outer surface of the lower half of the outer surface of the tube portion 30 with respect to gravity and covers the outer surface on the sealing portion 40 side. Specifically, as shown in FIGS. 4 (b) and 5 (b), an area including the apex portion 34 below the gravity on the outer surface of the tube portion 30, and an outer surface of the tube portion 30. It has a shape that covers the region including the connecting portion 36 between the tube bulb portion 30 and the sealing portion 40. The tube covering portion 72 </ b> B transmits light from the arc tube 20.

  The support portion 74B is fixed to the sealing portion 40 of the arc tube 20 with an inorganic adhesive C such as cement filled in the inner surface of the support portion 74B.

  Note that the end surface of the tube covering portion 72 </ b> B on the secondary mirror 60 side is in contact with the end surface of the secondary mirror 60.

  In the light source device 110 </ b> B according to the second embodiment, the region including the apex portion 34 below the gravity on the outer surface of the tube portion 30, the tube portion 30 and the sealing portion 40 on the outer surface of the tube portion 30, The region including the connecting portion 36 and the region including the connecting portion 38 between the tube portion 30 and the sealing portion 50 on the outer surface of the tube portion 30 are covered with the heat retaining member 70 </ b> B and the sub mirror 60.

  As described above, the light source device 110B according to the second embodiment differs from the light source device 110 according to the first embodiment in the configuration of the heat retaining member, but at least a tube as in the light source device 110 according to the first embodiment. A region including the lower apex portion 34 with respect to gravity on the outer surface of the portion 30, and a region including the connection portions 36 and 38 of the tube portion 30 and the sealing portions 40 and 50 on the outer surface of the tube portion 30. Since the arc tube 20 is cooled by the cooling fan 710 because it is covered by the tube covering portion 72B and the sub mirror 60, the coldest portion in the tube portion 30 (the lower apex portion 34 or the tube in the tube portion 30). It is possible to keep the connection portions 36, 38) between the ball portion 30 and the sealing portions 40, 50 warm. As a result, it is possible to suppress a decrease in the light amount of the arc tube 20 due to blackening and the occurrence of breakage of the arc tube 20, and local bulges occur in the upper apex portion 32 of the bulb portion 30, or white It is possible to suppress the deterioration of the lifetime of the light source device 110B.

  Therefore, the light source device 110B according to the second embodiment is a light source device capable of further increasing the luminance while extending the life of the light source device.

  The light source device 110B according to the second embodiment has the same configuration as the light source device 110 according to the first embodiment except that the configuration of the heat retaining member is different. Of which, it has the relevant effect.

  Although the light source device and the projector of the present invention have been described based on the above embodiments, the present invention is not limited to the above embodiments, and can be implemented in various modes without departing from the scope of the invention. For example, the following modifications are possible.

(1) In the light source device 110 according to Embodiment 1 described above, a predetermined gap is provided between the heat retaining member 70 and the secondary mirror 60 so that the heat retaining member 70 is located outside the secondary mirror 60. Although the case where it is disposed has been described as an example, the present invention is not limited to this. It is good also as a structure by which a heat retention member becomes an inner side with respect to a secondary mirror. Moreover, it is good also as a structure which does not provide a space | gap between a heat retention member and a secondary mirror, ie, closely contacts a heat retention member and a secondary mirror.

(2) In the light source device 110 </ b> B according to the second embodiment, the heat retaining member 70 </ b> B has a shape that divides the heat retaining member 70 described in the first embodiment into approximately half and further reduces the heat retaining member 70 once. Although the heat insulating member 70B is fixed to the sealing portion 40, the present invention is not limited to this, and the heat insulating member having a shape obtained by dividing the heat insulating member 70 described in the first embodiment into approximately half is sealed. It may be fixed to the portion 40. In this case, a predetermined gap exists between the secondary mirror 60.

(3) In the light source devices 110 and 110B according to the above-described embodiments, the case where the heat retaining members 70 and 70B are made of quartz glass has been described as an example, but the present invention is not limited thereto. Any material that is excellent in heat resistance and light transmittance may be used. For example, sapphire or quartz may be used.

(4) In the light source devices 110 and 110B according to each of the above embodiments, the secondary mirror is used as the reflecting means disposed in the arc tube, but the present invention is not limited to this, and the reflecting means is used as the reflecting means. It is also preferable to use a membrane. Further, in the light source devices 110 and 110B according to each of the above embodiments, the light source device in which the sub-mirror as the reflecting means is disposed on the arc tube is described as an example, but the present invention is limited to this. It is also possible to apply the present invention to a light source device in which a secondary mirror is not provided.

(5) In the light source devices 110 and 110B according to the above-described embodiments, the ellipsoidal reflector is used as the reflector. However, the present invention is not limited to this, and it is also preferable to use a parabolic reflector. In this case, the concave lens may not be provided.

(6) In the projector 1000 according to the first embodiment, the lens integrator optical system including a lens array is used as the light uniformizing optical system. However, the present invention is not limited to this, and includes a rod member. A rod integrator optical system can also be preferably used.

(7) The projector 1000 according to the first embodiment is a transmissive projector, but the present invention is not limited to this. The present invention can also be applied to a reflection type projector. Here, “transmission type” means that an electro-optic modulation device as a light modulation means, such as a transmission type liquid crystal device, transmits light, and “reflection type” This means that an electro-optic modulation device as a light modulation means, such as a reflective liquid crystal device, is a type that reflects light. Even when the present invention is applied to a reflective projector, the same effect as that of a transmissive projector can be obtained.

(8) In the projector 1000 according to the first embodiment, the projector using the three liquid crystal devices 400R, 400G, and 400B has been described as an example. However, the present invention is not limited to this, and one projector, The present invention can also be applied to a projector using two or four or more liquid crystal devices.

(9) In the projector 1000 according to the first embodiment, the liquid crystal device is used as the electro-optic modulation device, but the present invention is not limited to this. In general, the electro-optic modulation device may be any device that modulates incident light in accordance with image information, and a micromirror light modulation device or the like may be used. For example, a DMD (digital micromirror device) (trademark of TI) can be used as the micromirror light modulator.

(10) The present invention is applied to a rear projection projector that projects from a side opposite to the side that observes the projected image, even when applied to a front projection projector that projects from the side that observes the projected image. Is also possible.

FIG. 3 shows an optical system of the projector 1000 according to the first embodiment. The figure shown in order to demonstrate the light source device 110 which concerns on Embodiment 1. FIG. The figure shown in order to demonstrate the heat retention member 70. FIG. The figure shown in order to demonstrate the light source device 110B which concerns on Embodiment 2. FIG. The figure shown in order to demonstrate the heat retention member 70B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Ellipsoidal reflector, 12 ... Opening part, 14 ... Reflection concave surface, 20 ... Light emission tube, 30 ... Tube part, 32 ... Upper vertex part, 34 ... Lower vertex part, 36, 38 ... Tube part Connection part with sealing part, 40, 50 ... Sealing part, 42, 52 ... Electrode, 44, 54 ... Metal foil, 46, 56 ... Lead wire, 60 ... Secondary mirror, 62 ... Opening part, 64 ... Reflective concave surface , 70, 70B ... heat insulating member, 72, 72B ... tube cover, 74, 74B, 76 ... support, 90 ... concave lens, 100 ... illumination device, 110, 110B ... light source device, 120 ... first lens array, 122 DESCRIPTION OF SYMBOLS 1st small lens, 130 ... 2nd lens array, 132 ... 2nd small lens, 140 ... Polarization conversion element, 150 ... Superimposing lens, 200 ... Color separation light guide optical system, 210, 220 ... Dichroic mirror, 230, 240 , 250 ... reflective mirror, 60 ... Incident side lens, 270 ... Relay lens, 300R, 300G, 300B ... Condensing lens, 400R, 400G, 400B ... Liquid crystal device, 500 ... Cross dichroic prism, 600 ... Projection optical system, 1000 ... Projector, C ... Inorganic system Adhesive, OC ... light axis, SCR ... screen

Claims (8)

An arc tube having a tube bulb portion including a pair of electrodes arranged along the illumination optical axis and a pair of sealing portions extending on both sides of the tube bulb portion;
A reflector disposed on one sealing portion side of the arc tube, and reflecting light from the arc tube toward the illuminated region side;
A tube covering portion that covers at least a region including a lower apex portion with respect to gravity on the outer surface of the tube portion and a region including a connection portion between the tube portion and the sealing portion on the outer surface of the tube portion. And a heat retaining member having a support portion disposed at both ends of the tube covering portion and fixed to the pair of sealing portions,
The light source device, wherein the tube covering portion transmits light from the arc tube. The light source device according to claim 1,
The light source device according to claim 1, wherein the tube covering portion has a shape that covers a lower half of the outer surface of the tube portion with respect to gravity. The light source device according to claim 1 or 2,
The light source device, wherein the heat retaining member is made of quartz glass. In the light source device in any one of Claims 1-3,
A light source device, wherein an antireflection film is provided on a surface of the heat retaining member. In the light source device in any one of Claims 1-4,
The reflector has a reflective concave surface that reflects light from the arc tube toward the illuminated area side,
The light source device according to claim 1, wherein the concave concave surface has a curved shape that reflects and corrects the refraction when light passing through the tube covering portion is refracted on the surface of the tube covering portion. In the light source device according to any one of claims 1 to 5,
Reflecting means that is disposed on the other sealing portion side of the arc tube so as to cover the outer surface of the bulb portion on the illuminated area side and reflects light from the arc tube toward the arc tube. A light source device characterized by that. A light source device according to any one of claims 1 to 6,
An electro-optic modulator that modulates illumination light flux from the light source device according to image information;
A projector comprising: a projection optical system that projects light modulated by the electro-optic modulation device. The projector according to claim 7, wherein
A projector further comprising a cooling mechanism for cooling the light source device.