JP2011181309A - Light source device and projector - Google Patents

Abstract

Provided are a light source device and a projector that can be reduced in thickness by suppressing a reduction in luminance, and that have a high resistance to vibration and impact since a secondary mirror is difficult to drop off.
A light source device includes an arc tube having a bulb part and sealing parts, and a reflecting part and a base part having a shape in which one side is removed when cut along a plane. A reflector 30 having a reflector 30 having a reflecting portion 42 and a fixing portion 44 disposed opposite to the bulb portion 21 on the opposite side of the reflector 30, and a light emitting device disposed between a sealing portion 22b and a base portion 34. An adhesive C is provided between the sealing portion 22 b and the fixing portion 44 to fix the tube 20 and the reflector 30. The base 34 overlaps the fixing portion 44. The first portion 34a has a second portion 34b that does not overlap the fixing portion 44, and the distance between the second portion 34b and the sealing portion 22b is greater than the distance between the first portion 34a and the sealing portion 22b. Is also small.
[Selection] Figure 3

Description

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

  As a light source device used for the projector, it has a light emitting tube having a tube portion and a pair of sealing portions extended on both sides of the tube portion, and a shape in which one side is deleted when cut by a predetermined plane, A reflector having a reflection part that reflects light emitted from the bulb part to the illuminated area side, and a light pipe disposed between the reflector and the light emitted from the bulb part are arranged on the opposite side of the reflector. 2. Description of the Related Art A light source device that includes a secondary mirror that reflects toward a part is known (see, for example, Patent Document 1).

  According to such a configuration of the light source device, one side of the reflector, that is, the side where the secondary mirror is located is deleted, so that the thickness is reduced. On the other hand, the light is emitted from the tube portion to the side where the reflector is removed. The reflected light is reflected by the secondary mirror and effectively used, so that a decrease in luminance can be suppressed. In such a light source device, the base part extended from the reflecting part of the reflector and the sealing part of the arc tube are fixed, and the fixing part extended from the reflecting part of the secondary mirror and the sealing part of the arc tube And are fixed.

JP 2007-335196 A

  However, in the light source device configured as described above, since the fixing portion of the secondary mirror is fixed to the lower side in the gravity direction of the sealing portion of the arc tube, the secondary mirror is easily removed from the arc tube, and vibration and impact are caused. There was a problem of low resistance to aging. In addition, the base of the reflector has a shape in which approximately 1/2 of the substantially cylindrical shape is deleted, but since the connection portion with the base in the reflection portion is opened, the larger the cross section of the base, the more the reflection portion. There is a problem that the area is reduced and the luminance is lowered.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A light source device according to this application example includes an arc tube having a tube portion and a pair of sealing portions extending along the illumination optical axis on both sides of the tube portion, A first reflecting portion that has a shape in which one side is deleted when cut along the plane of the light, and reflects the light emitted from the bulb portion toward the illuminated area, and the pair of seals from the first reflecting portion. A reflector having a base extending along one of the stop portions, and a second portion disposed opposite to the bulb portion and disposed opposite to the reflector with the arc tube interposed therebetween. A sub-mirror having a reflecting portion, a fixing portion extending from the second reflecting portion along the one sealing portion, and between the one sealing portion and the base portion The arc tube and the reflector are disposed and fixed between the one sealing portion and the fixing portion. And an adhesive for fixing the arc tube and the secondary mirror, and the base has a first portion that overlaps the fixing portion and a second portion that does not overlap the fixing portion, The distance between the second part of the base and the one sealing part is smaller than the distance between the first part of the base and the one sealing part.

  According to this configuration, one side of the reflector is deleted and thinned, and light emitted from the bulb portion of the arc tube to the one side is reflected by the secondary mirror and used effectively. Therefore, it is possible to reduce the thickness of the light source device while suppressing a decrease in luminance.

  Moreover, according to this structure, the 1st part of the base part of a reflector has overlapped with the fixing | fixed part of the submirror. For this reason, in addition to fixing the fixing portion to the sealing portion with an adhesive, an adhesive is also disposed between the first portion of the base and the fixing portion, so that a part of the fixing portion is adhesive. Between the sealing part and the first part of the base. This makes it difficult for the secondary mirror to fall off the arc tube, and improves resistance to vibration and impact.

By the way, the distance between the first portion of the base and the sealing portion is the sum of the distance between the sealing portion and the fixing portion, the thickness of the fixing portion, and the distance between the fixing portion and the first portion. When the cross section of the base is substantially circular, the distance between the second portion of the base that does not overlap the fixed portion and the sealing portion is also substantially the same as the distance between the first portion and the sealing portion. On the other hand, according to this configuration, the distance between the second portion of the base and the one sealing portion is smaller than the distance between the first portion of the base and the one sealing portion. For this reason, compared with the case where the cross section of a base is substantially circular, the opening by the side of the base in the 1st reflection part of a reflector can be made small, and the area of a 1st reflection part can be enlarged correspondingly. As a result, more light can be reflected by the first reflecting portion, so that a reduction in luminance is further suppressed.
As a result, it is possible to provide a light source device that suppresses a decrease in luminance while reducing the thickness, and that has a high resistance to vibration and impact since the secondary mirror does not easily fall off.

  Application Example 2 In the light source device according to the application example described above, the distance between the second portion of the base portion and the one sealing portion is the distance between the first portion of the base portion and the fixing portion. It is preferable that the distance is substantially the same.

  According to this configuration, the distance between the second portion of the base portion and the one sealing portion does not include the distance corresponding to the distance between the sealing portion and the fixing portion and the thickness of the fixing portion. For this reason, the opening of the base side in the 1st reflection part of a reflector can be made further smaller, and the area of the 1st reflection part can be enlarged further.

  Application Example 3 In the light source device according to the application example described above, it is preferable that the base covers the outer periphery of the one sealing part over a half circumference.

  According to this configuration, since the base of the reflector covers the outer periphery of the sealing portion of the arc tube more than half a circle, a part of the base overlaps with the fixed part of the secondary mirror, and a part of the base An adhesive can be disposed between the fixed portion.

  Application Example 4 A projector according to this application example includes an illumination device including the light source device described above, an electro-optic modulation device that modulates illumination light from the illumination device according to image information, and the electro-optic modulation. And a projection lens that projects the modulated light from the apparatus.

  According to this configuration, since the light source device of the present invention having high resistance to vibration and impact is provided while suppressing a reduction in luminance and being thinned, it is possible to provide a projector having high luminance, thinness, and high impact resistance.

1 is a diagram illustrating a schematic configuration of a projector according to a first embodiment. The figure which shows schematic structure of the light source device which concerns on 1st Embodiment. The figure which shows schematic structure of the light source device which concerns on 1st Embodiment. The figure which shows schematic structure of the light source device which concerns on 1st Embodiment. The figure which shows schematic structure of the light source device which concerns on 2nd Embodiment.

  The present embodiment will be described below with reference to the drawings. In each of the drawings to be referred to, the dimensional ratios, angles, and the like of the respective constituent elements are appropriately changed for easy understanding of the configuration.

(First embodiment)
<Projector>
First, the projector according to the first embodiment will be described with reference to FIG. FIG. 1 is a diagram illustrating a schematic configuration of a projector according to the first embodiment.

  As shown in FIG. 1, the projector 1000 according to the first embodiment includes an illumination device 100, a color separation light guide optical system 200, three condenser lenses 300R, 300G, and 300B, and an electro-optic modulation device. The projector includes three liquid crystal devices 400R, 400G, and 400B, a cross dichroic prism 500, a projection lens 600, and a cooling mechanism (not shown).

  The illumination device 100 includes a light source device 10, a concave lens 90, a first lens array 120 having a plurality of first small lenses 122, a second lens array 130 having a plurality of second small lenses 132, and a polarization conversion element 140. And a superimposing lens 150.

  The light source device 10 includes an arc tube 20, a reflector 30, and a secondary mirror 40. The reflector 30 has a reflecting surface 31 (see FIGS. 2A and 2B) that is a part of a spheroid having a first focal point and a second focal point on the illumination optical axis OC. Further, the first focal point of the reflector 30 is located in the tube portion 21 of the arc tube 20 (see FIGS. 2A and 2B). The light source device 10 emits an illumination light beam that converges toward the second focal point of the reflector 30.

  The light source device 10 is configured to be replaceable by the user when the arc tube 20 reaches the end of its life. In the light source device 10, the side from which the light flux is emitted from the reflector 30 is also referred to as the illuminated region side. In the light source device 10, the side opposite to the illuminated region side is also referred to as the back side. The detailed configuration of the light source device 10 will be described later.

  The concave lens 90 is disposed on the illuminated area side of the light source device 10. The concave lens 90 emits the converged light from the light source device 10 toward the first lens array 120 as substantially parallel light. The first lens array 120 has a function as a light beam splitting optical element that splits the illumination light beam emitted from the concave lens 90 into a plurality of partial light beams. The first lens array 120 includes a plurality of first small lenses 122 arranged in a matrix in a plane substantially orthogonal to the illumination optical axis OC. 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 is an optical element for condensing a plurality of partial light beams divided by the first lens array 120 described above. The second lens array 130 includes a plurality of second small lenses 132 arranged in a matrix in a plane substantially orthogonal to the illumination optical axis OC corresponding to the plurality of first small lenses 122 of the first lens array 120. I have.

  The polarization conversion element 140 is a polarization conversion element that converts each partial light beam from the second lens array 130 into approximately one type of linearly polarized light having a uniform polarization direction and emits the converted light. The polarization conversion element 140 transmits one linear polarization component of the polarization component included in the illumination light beam from the light source device 10 as it is, and reflects the other linear polarization 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 separation layer in a direction parallel to the illumination optical axis OC, and converts the other linearly polarized light component reflected by the reflective layer into one linearly polarized light component. And a retardation plate.

  The superimposing lens 150 condenses a plurality of partial light beams emitted through the first lens array 120, the second lens array 130, and the polarization conversion element 140 and superimposes them in the vicinity of the image forming area of the liquid crystal devices 400R, 400G, and 400B. It is an optical element for making it. Note that the superimposing lens 150 is illustrated as a single lens in FIG. 1, but may be configured by a composite 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 illumination device 100 into three color lights of red light, green light, and blue light, and the respective color lights are liquid crystal devices 400R and 400G to be illuminated. , 400B.

  The dichroic mirrors 210 and 220 are optical elements on which a wavelength selection film that reflects a light beam in a predetermined wavelength region and transmits a light beam in another wavelength region is formed on a substrate. The dichroic mirror 210 disposed in the front stage of the optical path is a mirror that reflects a red light component and transmits other color light components. The dichroic mirror 220 disposed in the latter stage of the optical path is a mirror that reflects the green light component and transmits the blue light component.

  The red light component reflected by the dichroic mirror 210 is bent by the reflection mirror 230 and enters the image forming area of the liquid crystal device 400R for red light through the condenser lens 300R. The condenser lens 300R is provided to convert each partial light beam from the superimposing lens 150 into a light beam substantially parallel to each principal ray. The condensing lenses 300G and 300B disposed in the preceding stage of the optical path of the other liquid crystal devices 400G and 400B are configured in the same manner as the condensing lens 300R.

  Of the green light component and the blue light component that have passed through the dichroic mirror 210, the green light component is reflected by the dichroic mirror 220, passes through the condenser lens 300G, and enters the image forming area of the green light liquid crystal device 400G. On the other hand, the blue light component passes through the dichroic mirror 220 and passes through the incident side lens 260, the incident side reflection mirror 240, the relay lens 270, the emission side reflection mirror 250, and the condensing lens 300B. The light enters the image forming area of the liquid crystal device 400B. The incident side lens 260, the relay lens 270, and the reflection mirrors 240 and 250 have a function of guiding the blue light component transmitted through the dichroic mirror 220 to the liquid crystal device 400B.

  The incident side lens 260, the relay lens 270, and the reflection mirrors 240 and 250 are provided in the optical path of the blue light because the length of the optical path of the blue light is longer than the lengths of the optical paths of the other color lights. The reason for this is to prevent a decrease in light utilization efficiency due to light divergence and the like. The projector 1000 according to the first embodiment has such a configuration because the length of the optical path of blue light is long. However, the length of the optical path of red light is increased, and the incident side lens 260 and the relay are configured. The lens 270 and the reflection mirrors 240 and 250 may be used in the optical path of red light.

  The liquid crystal devices 400R, 400G, and 400B modulate each of the three color lights separated by the color separation light guide optical system 200 in accordance with image information, and are illumination targets of the illumination device 100. Although not shown, an incident-side polarizing plate is disposed between the condenser lenses 300R, 300G, and 300B and the liquid crystal devices 400R, 400G, and 400B, respectively, and the liquid crystal devices 400R, 400G, and 400B are cross dichroic. An exit-side polarizing plate is disposed between each prism 500.

  The incident-side polarizing plate, the liquid crystal devices 400R, 400G, and 400B, and the exit-side polarizing plate modulate the light of each incident color light. The liquid crystal devices 400R, 400G, and 400B are obtained by hermetically sealing a liquid crystal that is an electro-optical material on a pair of transparent glass substrates. The liquid crystal devices 400R, 400G, and 400B, for example, use polysilicon TFTs as switching elements to modulate the polarization direction of one type of linearly polarized light emitted from the incident-side polarizing plate according to a given image signal.

  The cross dichroic prism 500 is an optical element that forms a color image by synthesizing optical images modulated by the three liquid crystal devices 400R, 400G, and 400B and modulated for each color light emitted from the emission 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 projection lens 600 enlarges and projects the color image synthesized by the cross dichroic prism 500 onto a projection surface such as a screen SCR. Thereby, an image is formed on a projection surface such as a screen SCR.

<Light source device>
Next, the light source device according to the first embodiment will be described with reference to FIG. FIG. 2 is a diagram illustrating a schematic configuration of the light source device according to the first embodiment. Specifically, FIG. 2A is a perspective view illustrating a configuration of a main part of the light source device 10. FIG. 2B is a cross-sectional view along the line AA ′ when cut along a plane S1 including the illumination optical axis OC in FIG.

  Hereinafter, a case where the projector 1000 is arranged in a so-called stationary state will be described as an example. The arrangement of the components of the light source device 10 in FIGS. 2A and 2B corresponds to the stationary state of the projector 1000.

  In the stationary state of the projector 1000, the direction of gravity is a direction substantially orthogonal to the illumination optical axis OC, and is a direction from the reflector 30 side toward the secondary mirror 40 side. The upper part in the direction of gravity is also referred to simply as the upper part, and the lower part in the direction of gravity is also referred to as the lower part.

  A direction along the illumination optical axis OC is also referred to as an X direction, and a direction along the gravity direction is also referred to as a Z direction. A direction substantially orthogonal to the X direction and the Z direction is also referred to as a Y direction. The Y direction is a direction along the horizontal direction when the projector 1000 is stationary. The above-described plane S1 is a plane including the illumination optical axis OC while being configured by the X direction and the Z direction.

  The light source device 10 according to the first embodiment includes an arc tube 20, a reflector 30, a sub mirror 40, and an adhesive C as shown in FIGS. 2 (a) and 2 (b). In FIG. 2A, the lead wires 28a and 28b and the adhesive C are not shown.

  The arc tube 20 includes a bulb portion 21, a pair of sealing portions 22a and 22b, a pair of electrodes 24a and 24b, a pair of metal foils 26a and 26b, and a pair of lead wires 28a and 28b. Yes. 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 sealing portions 22a and 22b are extended from the tube portion 21 on both sides along the illumination optical axis OC. The sealing part 22a is arranged on the illuminated area side of the tube part 21, and the sealing part 22b is arranged on the opposite side of the illuminated part side of the tube part 21, that is, on the back side. The tube portion 21 and the sealing portions 22a and 22b are made of, for example, quartz glass and are integrally formed. In the tube portion 21, for example, mercury, rare gas and a small amount of halogen are sealed.

  As shown in FIG. 2B, the electrodes 24a and 24b are arranged such that one end portions sealed in the tube portion 21 face each other. A discharge portion is formed at one end of the electrodes 24a and 24b facing each other. The electrode 24a extends along the illumination optical axis OC toward the sealing portion 22a, and the end thereof is electrically connected to the metal foil 26a. The electrode 24b extends to the sealing portion 22b side along the illumination optical axis OC, and the end thereof is electrically connected to the metal foil 26b. The electrodes 24a and 24b are made of a metal such as tungsten, for example.

  The metal foils 26a and 26b extend along the illumination optical axis OC. The metal foil 26a is sealed in the sealing portion 22a, and the metal foil 26b is sealed in the sealing portion 22b. The metal foils 26a and 26b are made of a metal such as molybdenum, for example.

  The lead wires 28a and 28b extend along the illumination optical axis OC. One end portion side of the lead wire 28a is sealed in the sealing portion 22a and is electrically connected to the metal foil 26a. The other end portion of the lead wire 28a extends from the sealing portion 22a. One end portion side of the lead wire 28b is sealed in the sealing portion 22b and is electrically connected to the metal foil 26b. The other end portion of the lead wire 28b extends from the sealing portion 22b. The lead wires 28a and 28b are made of a metal such as molybdenum or tungsten, for example. When a voltage is applied to the lead wires 28a and 28b, a potential difference is generated between the electrodes 24a and 24b, and a discharge is generated in the tube portion 21 to generate an arc image.

As shown in FIGS. 2A and 2B, the reflector 30 includes a reflecting portion 32 as a first reflecting portion and a base portion 34. The reflection part 32 and the base part 34 are integrally formed. As a material for the base material of the reflector 30, for example, crystallized glass, alumina (Al ₂ O ₃ ), or the like can be suitably used.

  The reflecting portion 32 has a shape that is approximately ¼ of an elliptic sphere obtained by rotating the ellipsoid about the illumination optical axis OC as the rotation center axis. More specifically, when the reflecting portion 32 is cut by a plane constituted by the Y direction and the Z direction out of the elliptic sphere, approximately 1/2 in the direction along the illumination optical axis OC is deleted, When cut along a predetermined plane S2 constituted by the X direction and the Y direction, the end 30z on the side of the secondary mirror 40 (reflecting part 42) in the Z direction is removed (FIG. 2A). reference).

  The position where the above-mentioned elliptical sphere is cut along the plane S2 is closer to the secondary mirror 40 than the illumination optical axis OC in the Z direction. Therefore, the reflection part 32 has covered the outer periphery of the arc_tube | light_emitting_tube 20 exceeding a semicircle. Since the end portion 30z is deleted, the opening portion on the illuminated region side of the reflecting portion 32 has a substantially semicircular shape. By making the reflection part 32 into such a shape, the reflector 30 can be thinned.

The reflecting portion 32 has a reflecting surface 31 on the inner surface facing the arc tube 20. The reflecting surface 31 is a part of a spheroid having a first focal point and a second focal point on the illumination optical axis OC. The reflecting portion 32 is disposed so that the bulb portion 21 is positioned in the vicinity of the first focal point with respect to the arc tube 20. The reflecting part 32 reflects the light emitted from the tube part 21 toward the second focal position on the illuminated area side on the reflecting surface 31. 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 on the reflecting surface 31. The reflecting portion 32 is provided with an opening 33 at a connection portion with the base portion 34 on the back side.

  The base portion 34 extends from the reflecting portion 32 to the back side along the sealing portion 22b. Of the cylindrical shape extending along the illumination optical axis OC, the base 34 is the same plane S2 as that of the reflection unit 32 at a position closer to the secondary mirror 40 (fixed portion 44) than the illumination optical axis OC in the Z direction. And the fixed portion 44 side is removed. Therefore, the base 34 covers the outer periphery of the sealing portion 22b beyond a half circumference.

  An adhesive C is filled between the base portion 34 and the sealing portion 22b, and the reflector 30 and the arc tube 20 are fixed to each other by the adhesive C. The adhesive C is, for example, a silica-based or alumina-based inorganic adhesive. As such an inorganic adhesive, for example, “SUMICERAM (registered trademark)” manufactured by Sumitomo Chemical Co., Ltd. can be used.

  The sub mirror 40 is disposed on the opposite side of the reflector 30 with the arc tube 20 interposed therebetween. That is, the sub mirror 40 is located on the lower side of the arc tube 20 and on the side where the end 30z of the reflector 30 is removed. The sub mirror 40 includes a reflection part 42 as a second reflection part and a fixing part 44. The reflection part 42 and the fixing part 44 are formed integrally. The secondary mirror 40 is made of, for example, hard glass or quartz glass. The material of the secondary mirror 40 may be a metal.

  The reflector 42 has a substantially hemispherical shape in which, when cut by a plane that is parallel to the plane S2 and includes the illumination optical axis OC among the spheres, approximately ½ on the reflector 30 side in the Z direction is deleted. Yes. The reflection part 42 is arrange | positioned so that the opposite side to the reflector 30 of the bulb part 21 may be covered. The reflecting portion 42 has a reflecting surface 41 on the inner surface side facing the tube portion 21.

The reflection part 42 reflects light emitted from the tube part 21 toward the sub mirror 40 toward the tube part 21 (reflection surface 31) on the reflection surface 41. Thereby, the light inject | emitted from the tube | bulb part 21 to the submirror 40 side can be returned to the reflector 30 side, and can be used effectively as an illumination light beam. On the reflecting surface 41, for example, a reflecting layer made of a dielectric multilayer film of tantalum oxide (Ta ₂ O ₅ ) and silicon oxide (SiO ₂ ) is formed.

  The fixing portion 44 extends from the reflecting portion 42 to the back side along the sealing portion 22b. The fixed portion 44 is cut in the same plane as the case of the reflecting portion 42 out of the substantially cylindrical shape extending along the illumination optical axis OC, and approximately 1/2 on the reflector 30 side in the Z direction is deleted. It has a different shape. That is, the fixing portion 44 covers substantially the half circumference of the outer periphery of the sealing portion 22b. An adhesive C is filled between the fixed portion 44 and the sealing portion 22b, and the arc tube 20 and the sub mirror 40 are fixed to each other by the adhesive C.

  According to the configuration of the light source device 10 according to the first embodiment, the reflector 30 is thinned by deleting the end 30z on the side of the secondary mirror 40. On the other hand, since the light emitted from the arc tube 20 to the sub mirror 40 side is reflected by the reflecting portion 42 and can be effectively used as an illumination light beam, the luminance is reduced due to the elimination of the end 30z of the reflector 30. Is suppressed. Therefore, the light source device 10 can be thinned while suppressing a decrease in luminance.

  Subsequently, the cross-sectional shape and positional relationship of the sealing portion 22b of the arc tube 20 in the light source device 10, the base portion 34 of the reflector 30, and the fixing portion 44 of the sub mirror 40 will be further described with reference to FIGS. . 3 and 4 are diagrams illustrating a schematic configuration of the light source device according to the first embodiment. Specifically, FIG. 3A is a side view of the light source device 10, and FIG. 3B is a rear view of the light source device 10. FIG. 4 is a partially enlarged view of FIG.

  As shown in FIGS. 3A and 3B, the reflector 30 covers the outer circumference of the arc tube 20 over a half circumference and covers a part of the secondary mirror 40. The base portion 34 of the reflector 30 has a first portion 34a positioned below the illumination optical axis OC and a second portion 34b positioned above the illumination optical axis OC. In the base portion 34, the first portion 34 a is a portion that overlaps the fixing portion 44 of the sub mirror 40, and the second portion 34 b is a portion that does not overlap the fixing portion 44.

  As shown in FIG. 3B, the cross-sectional shape of the first portion 34a when the base 34 is cut by a plane constituted by the Y direction and the Z direction is, for example, a circle centered on the illumination optical axis OC. Of the substantially half of the lower side, the lower side is further deleted on the plane S2 (see FIG. 2A). The cross-sectional shape of the second portion 34b is, for example, a shape in which substantially the lower half of the ellipse having a long axis passing through the illumination optical axis OC and parallel to the Y direction is deleted.

  The opening 33 of the reflecting portion 32 overlaps the cavity of the base 34 in a plan view from the back side, and the cross-sectional shape thereof is similar to the cross-sectional shape of the base 34. Moreover, the cross-sectional shape of the sealing portion 22b is, for example, a circle centered on the illumination optical axis OC. The cross-sectional shape of the fixed portion 44 is, for example, a shape in which substantially the upper half of a circle centered on the illumination optical axis OC is deleted.

  The adhesive C is disposed between the sealing portion 22 b and the second portion 34 b and between the sealing portion 22 b and the fixing portion 44. Further, the adhesive C is also disposed between a portion of the fixing portion 44 that overlaps the first portion 34a and the first portion 34a. Therefore, the fixing portion 44 is fixed to the sealing portion 22b and is held between the sealing portion 22b and the first portion 34a via the adhesive C.

  In the light source device having a configuration in which the fixing portion of the secondary mirror does not overlap the base portion of the reflector as in the light source device described in Patent Document 1, the secondary mirror is not held by the reflector or the like, and the secondary mirror is fixed by the arc tube It depends on the adhesive force of the adhesive disposed between the sealing part and the fixing part. However, since the secondary mirror is located below the reflector, the secondary mirror easily falls off the arc tube, and resistance to vibration and impact is reduced.

  On the other hand, according to the configuration of the light source device 10 according to the first embodiment, the fixing portion 44 is fixed to the sealing portion 22b with the adhesive C, and the sealing portion 22b is interposed via the adhesive C. And the base 34 (first portion 34a). This makes it difficult for the secondary mirror 40 to fall off the arc tube 20 and improves resistance to vibration and impact. As a result, it is possible to provide the light source device 10 that suppresses a decrease in luminance and is thinned, and that has a high resistance to vibration and impact, in which the secondary mirror 40 is difficult to drop off.

  By the way, in the normal light source device, like the light source device described in Patent Document 1, the base portion of the reflector has a shape obtained by removing approximately 1/2 of the substantially cylindrical shape, and the cross-sectional shape thereof is approximately semicircular. . Temporarily, as shown by a two-dot chain line in FIG. 4, the reflector 30 has a base portion 54 having a cross-sectional shape in which the lower side of the plane S2 (see FIG. 2A) is removed from a circle centered on the illumination optical axis OC. Is provided. At this time, the opening 53 of the reflecting portion 32 has a shape corresponding to the cross section of the base 54. Therefore, the larger the cross section of the base portion 54, the correspondingly the area of the reflecting portion 32 is reduced and the luminance is lowered.

  In FIG. 4, the distance between the base portion 54 and the sealing portion 22b is D1. Further, the distance between the base portion 54 and the fixed portion 44 is D2. The distance D1 corresponds to the sum of the distance between the sealing portion 22b and the fixed portion 44, the thickness of the fixed portion 44, and the distance D2. Since the base 54 and the sealing part 22b are concentric circles, the distance from the sealing part 22b is substantially the same D1 in any part of the base 54.

  On the other hand, in the light source device 10, the distance between the first portion 34 a of the base portion 34 and the sealing portion 22 b is D1 as in the case of the above-described base portion 54, and the first portion 34 a and the fixing portion 44. The distance to is D2. However, since the cross-sectional shape of the second portion 34b is a semi-elliptical shape having a long axis passing through the illumination optical axis OC and parallel to the Y direction, the distance between the second portion 34b and the sealing portion 22b is the first distance. It is smaller than the distance D1 between the portion 34a and the sealing portion 22b. Therefore, the cross section of the base 34 is smaller than the cross section of the base 54.

  More specifically, the distance between the second portion 34b and the sealing portion 22b is the smallest in the semi-elliptical short axis direction, that is, in the central portion in the Y direction of the second portion 34b, and away from the central portion. Therefore, it gradually increases (as it approaches the first portion 34a). The distance between the central portion of the second portion 34b in the Y direction and the sealing portion 22b is, for example, D2. In the first place, the distance between the second portion 34b and the sealing portion 22b may not include the distance corresponding to the distance between the sealing portion 22b and the fixing portion 44 and the thickness of the fixing portion 44. It can also be said that the second portion 34b of 34 can be made into a semi-elliptical shape, and the shortest distance between the second portion 34b and the sealing portion 22b can be set to D2.

  According to such a configuration of the light source device 10, the cross section of the base portion 34 can be made smaller than when the cross section is substantially circular like the base portion 54. For this reason, since the opening part 33 by the side of the base 34 in the reflection part 32 of the reflector 30 can be made smaller, the area of the reflection part 32 can be enlarged correspondingly. Thereby, since more light can be reflected by the reflection part 32, the fall of a brightness | luminance is suppressed more.

(Second Embodiment)
<Light source device>
Next, a light source device according to a second embodiment will be described with reference to FIG. The light source device according to the second embodiment differs from the light source device according to the first embodiment in the cross-sectional shape of the base portion of the reflector, but the other configurations are the same.

  FIG. 5 is a diagram illustrating a schematic configuration of a light source device according to the second embodiment. Specifically, FIG. 5 is a rear view of the light source device, and is a partially enlarged view of the rear surface corresponding to FIG. In addition, about the component which is common in 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As illustrated in FIG. 5, the light source device 12 according to the second embodiment includes an arc tube 20, a reflector 30 </ b> A, and a secondary mirror 40.

  The reflector 30 </ b> A includes a reflection portion 36 as a first reflection portion and a base portion 38. The reflection portion 36 is provided with an opening 37 at a connection portion with the base portion 38 on the back side. The base portion 38 has a different cross-sectional shape when cut along a plane constituted by the Y direction and the Z direction with respect to the base portion 34 in the first embodiment. The base portion 38 has a first portion 38a, a second portion 38b, and a third portion 38c.

  The first portion 38 a is a portion located below the illumination optical axis OC, and is a portion that overlaps with the fixing portion 44 of the secondary mirror 40. The first portion 38a has substantially the same shape as the first portion 34a in the first embodiment. The distance between the first portion 38a and the fixing portion 44 is substantially the same as the distance D2 between the first portion 34a and the fixing portion 44 in the first embodiment.

  The second portion 38 b and the third portion 38 c are portions that are located above the illumination optical axis OC and are portions that do not overlap with the fixed portion 44. The cross-sectional shape of the second portion 38b in the base portion 38 is, for example, a part on the upper side of a circle centered on the illumination optical axis OC. Accordingly, the distance between the second portion 38b and the sealing portion 22b is substantially the same in any portion. The distance between the second portion 38b and the sealing portion 22b is substantially the same as the distance D2 between the first portion 38a and the fixing portion 44.

  The third portion 38c is a portion that connects the first portion 38a and the second portion 38b. The distance between the third portion 38c and the sealing portion 22b gradually increases as the distance from the second portion 38b increases (as the distance approaches the first portion 38a). Further, the third portion 38 c has a distance appropriately set between the third portion 38 c and the fixed portion 44 so as not to contact the fixed portion 44.

  According to the configuration of the light source device 12, the distance between the first portion 38a and the fixing portion 44 in the base portion 38 of the reflector 30A is substantially the same as the distance between the first portion 34a and the sealing portion 22b in the first embodiment. The same D2. However, in any portion of the second portion 38b, the distance between the second portion 38b and the sealing portion 22b is substantially the same as D2. That is, the cross section of the base portion 38 is smaller than the cross section of the base portion 34. Therefore, since the opening 37 in the reflection part 36 can be made smaller than the reflector 30 of the first embodiment, the area of the reflection part 36 can be increased accordingly.

  According to the configuration of the light source device 12 according to the second embodiment, similarly to the light source device 10 according to the first embodiment, the reflector 30A is thinned, while being emitted from the arc tube 20 to the sub mirror 40 side. Therefore, the light source device 12 can be reduced in thickness while suppressing a decrease in luminance.

  Further, according to the configuration of the light source device 12 according to the second embodiment, the fixing portion 44 is fixed to the sealing portion 22b, and the first portion of the sealing portion 22b and the base portion 38 is interposed via the adhesive C. It is held between the portion 38a. Thereby, also in the light source device 12 according to the second embodiment, similarly to the light source device 10 according to the first embodiment, the secondary mirror 40 is not easily dropped from the arc tube 20 and is resistant to vibration and impact. improves.

  Furthermore, according to the configuration of the light source device 12 according to the second embodiment, since the opening 37 in the reflection portion 36 of the reflector 30A can be made smaller than the light source device 10 in the first embodiment, the reflection portion 36 can be made smaller. Can be increased accordingly. Thereby, since more light can be reflected by the reflection part 36, the fall of a brightness | luminance can further be suppressed.

  As described above, the light source device and the projector according to the present invention have been described based on the above embodiment, but the present invention is not limited thereto, and various modifications can be made without departing from the spirit of the present invention. . As modifications, for example, the following can be considered.

(Modification 1)
In the configuration of the light source device of the above embodiment, the secondary mirror has a shape in which approximately 1/2 in the Z direction is deleted and covers approximately half of the outer periphery of the arc tube, but the present invention is limited to this configuration. Not. The sub mirror may cover the outer circumference of the arc tube beyond the half circumference.

  By configuring the secondary mirror to cover the outer periphery of the arc tube beyond a half circumference, it is possible to enlarge a region where the fixed portion of the secondary mirror and the base portion of the reflector overlap as compared with the above embodiment. Thereby, compared with the said embodiment, omission of a secondary mirror can be suppressed more effectively. However, a part of the base part of the reflector may overlap the fixed part of the secondary mirror, so that the cross section of the base part may be larger than that in the above embodiment.

(Modification 2)
In the configuration of the projector of the above embodiment, the lens integrator optical system including the first lens array and the second lens array is used as the light uniformizing optical system, but the present invention is not limited to this. As the light homogenizing optical system, for example, a rod integrator optical system including a light guide rod can be used.

(Modification 3)
The projector in the above embodiment is a transmissive projector, but the present invention is not limited to this. For example, a reflective projector may be used. 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.

(Modification 4)
The projector in the above embodiment is a projector using three liquid crystal devices, but the present invention is not limited to this. The present invention can also be applied to a projector using one, two, four or more liquid crystal devices, for example.

(Modification 5)
In the configuration of the projector of the above embodiment, a 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.

(Modification 6)
The present invention can be applied to a front projection type projector that projects from the side that observes the projected image and a rear projection type projector that projects from the side opposite to the side that observes the projected image.

(Modification 7)
In the said embodiment, although the example which applied the light source device of this invention to the projector was demonstrated, this invention is not limited to this. The light source device of the present invention can also be applied to other optical equipment such as an optical disk device.

  DESCRIPTION OF SYMBOLS 10,12 ... Light source device, 20 ... Light emission tube, 21 ... Tube part, 22a, 22b ... A pair of sealing part, 30, 30A ... Reflector, 32, 36 ... Reflection part as 1st reflection part, 34, 38 ... Base, 34a, 38a ... First part, 34b, 38b ... Second part, 40 ... Secondary mirror, 42 ... Reflecting part as second reflecting part, 44 ... Fixed part, 100 ... Illuminating device, 120 ... 1st lens array, 122 ... 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 ... Reflection mirror, 260 ... Incident side lens, 270 ... Relay lens, 300R, 300G, 300B ... Condensing lens, 400R, 400G, 400B ... Electro-optic modulation The liquid crystal device as location, 500 ... cross dichroic prism 600 ... projection lens 1000 ... projector, C ... adhesives, OC ... illumination optical axis.

Claims (4)

An arc tube having a tube portion and a pair of sealing portions extending along the illumination optical axis on both sides of the tube portion;
A first reflecting portion that has a shape in which one side is deleted when cut along a predetermined plane and reflects light emitted from the bulb portion toward the illuminated region; and the pair of pairs from the first reflecting portion. A reflector having a base extending along one of the sealing portions, and
A second reflecting portion disposed opposite to the reflector with the arc tube interposed therebetween, and the one sealing portion from the second reflecting portion; A secondary mirror having a fixed portion extending along
The arc tube and the reflector are disposed between the one sealing portion and the base portion, and are disposed between the one sealing portion and the fixing portion. An adhesive for fixing the secondary mirror,
The base has a first portion that overlaps with the fixed portion, and a second portion that does not overlap with the fixed portion,
The distance between the second part of the base and the one sealing part is smaller than the distance between the first part of the base and the one sealing part. . The light source device according to claim 1,
The distance between the second part of the base and the one sealing part is substantially the same as the distance between the first part of the base and the fixing part. It is a light source device of Claim 1 or 2, Comprising: The said base has covered the outer periphery of said one said sealing part exceeding a half periphery, The light source device characterized by the above-mentioned. A lighting device comprising the light source device according to any one of claims 1 to 3,
An electro-optic modulation device that modulates illumination light from the illumination device according to image information;
A projection lens that projects the modulated light from the electro-optic modulator;
A projector comprising:

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