JP2006350387A - Light source device and video display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device capable of improving the efficiency of fetching light by enhancing the efficiency of condensing light on a predetermined small-diameter area though its constitution is simple and compact, and to provide a video display device. <P>SOLUTION: The light source device has a light emitting tube 20 and a reflector 44. The electrode shafts O1 of the main electrodes 21 and 22 of the light emitting tube 20 are made to cross with the optical axis LA of emitted light, and the reflector 44 made of metallic base material is formed of a first reflector part 45 comprising a spherical surface and a second reflector part 46 comprising an ellipsoid in front, and a lens which condenses emitted light and radiates it to a predetermined direction or area is provided inside the second reflector part 46. Then, the sealing parts 23a and 23b of the light emitting tube 20 and the first and the second reflector parts 45 and 46 are fixed through heat radiation materials 60 and 60. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention has an arc tube in which a pair of main electrodes are arranged on one electrode axis, and a reflector that reflects the emitted light emitted from the arc tube. The present invention relates to a light source device and an image display device that intersect with an optical axis of incident light.

The background art of the present invention will be described with reference to FIGS. 17 (a) and 17 (b) are comparative explanatory views of the arrangement direction of the arc tube, FIG. 18 is a plan view showing a schematic configuration of the light source device of the optical axis parallel arrangement type, and FIG. It is a plane cross section which shows the behavior of the emitted light radiate | emitted from the light emission point of the parallel arrangement type light source device.
Conventionally, in light source devices used for projection display devices that require a light source with high brightness, illumination is generated by generating arc discharge such as a metal halide lamp, a xenon short arc lamp, or a high-pressure mercury lamp. The arc tube to be used is used.
As shown in FIG. 18, the light source device has a configuration including an arc tube 1 and a reflector 2 made of a heat-resistant glass substrate or a ceramic substrate that reflects the emitted light emitted from the arc tube 1.

  As shown in FIGS. 17 (a), 17 (b), and 18, the arc tube 1 includes an anode electrode 3 and a cathode electrode 4 that pass through a light emitting point (emission center) L0 and are arranged on both sides in a straight line. The tube 5 is enclosed in a tube 5, and can be roughly divided into a conventional optical axis parallel arrangement type and an optical axis vertical arrangement type according to the direction in which the arc tube 1 is arranged. A common central axis passing through the anode electrode and the cathode electrode is referred to as “electrode axis O1”.

An anode side lead rod 3A is connected to the anode electrode 3, and a molybdenum sheet 6 is welded to the anode side lead rod 3A.
The cathode electrode 4 is connected to a cathode lead bar 4A, and a molybdenum sheet 7 is welded to the cathode lead bar 4A. Reference numerals 5A and 5B denote sealing portions enclosing the anode side lead rod 3A and the cathode side lead rod 4A.

The optical axis parallel arrangement type means that in the X, Y, and Z axes shown in FIG. 17A, the electrode axis O1 of the arc tube 1 is in the X direction when the optical axis LA coincides with the X axis. . Further, the optical axis vertical arrangement type means that the electrode axis O1 of the arc tube 1 is in the Z direction as shown in FIG.
In the above configuration, the emitted light emitted from the arc tube 1 is irradiated in a predetermined direction or region by the reflector 2.

  By the way, in the case of the optical axis parallel arrangement type, as shown in FIGS. 18 and 19, the cathode electrode 4 is present in the irradiation direction of the emitted light as viewed from the light emitting point L0. However, there is a problem that the use efficiency of the emitted light emitted from the light source is lowered due to an obstacle that obstructs the path of the emitted light.

In order to improve this problem, Japanese Patent Application Laid-Open No. 2-55325 (Patent Document 1) discloses a light source device of an optical axis vertical arrangement type. This is referred to as “first prior art”.
However, in the light source device of the optical axis vertical arrangement type, the output distribution of light is likely to be biased. Therefore, as disclosed in Japanese Patent Laid-Open Nos. 4-242064 (Patent Document 2) and 6-214115 (Patent Document 3), etc. As described above, it has been proposed to improve the light output distribution by disposing a condenser lens or a Fresnel lens in the emission range of all the outgoing rays. This is the “second prior art”.

An example of the light source device according to the first prior art is shown in FIGS. FIG. 20 is a top view of a light source device of an optical axis vertical arrangement type according to an example of the first prior art, in which the reflecting surface of the reflector is an ellipsoid, and FIG. 21 is an ellipsoid of the light reflecting surface of the reflector. FIG. 5 is a side view of a light source device according to another example of the first prior art in which the electrode axis of the arc tube is arranged substantially perpendicular to the optical axis.
The light source device shown in FIGS. 20 and 21 has the same configuration as the light source device shown in FIGS. 18 and 19 except that the direction of the arc tube is different (optical axis vertical arrangement type). Here, the same code | symbol is attached | subjected to those equivalent to them, and detailed description is abbreviate | omitted.
20 and 21, the X axis is the optical axis direction, the Y axis is the height direction when viewed in the final assembly, the Z axis is the depth direction when viewed in the final assembly, and the XZ cross section is The figure when seen is a top view, and the figure when looking at the XY plane is a side view.

  The light source device of the optical axis vertical arrangement type according to the example shown in FIG. 20, among the emitted light beams emitted from the light emitting point L0, the emitted light beam reflected by the light reflecting surface that is an elliptical surface of the reflector 2 is a predetermined condensing point. There are a component that reaches Sp and a component that is irradiated and absorbed by the molybdenum sheet 6 on the anode electrode 3 side, such as an outgoing ray reflected by the reflection point 2a on the reflection surface.

That is, when viewed from the optical axis direction LA, there is a component in which the outgoing light beam irradiating the light reflecting surface behind the arc tube 1 is irradiated and absorbed by the anode electrode 3, the cathode electrode 4 and the molybdenum sheets 6, 7. As a result, the utilization efficiency of the emitted light emitted from the light source is reduced, and at the same time, the temperature of the sealed portions 5A and 5B of the arc tube 1 is increased.
Further, since the light beam of θ Loss from the optical axis LA does not irradiate the light reflecting surface, most of the light does not reach the condensing point Sp and becomes loss light.

The optical axis vertical arrangement type light source device according to another example shown in FIG. 21 has the electrode axis O1 of the arc tube 1 arranged substantially perpendicular to the optical axis LA, and the light reflecting surface of the reflector 2 is an elliptical surface. 1 is a side view of the light source device.
The light distribution of the arc tube 1 is within the angle range formed by LA-L0-2a (2b), and corresponds to the light distribution distribution θlamp shown in FIG. When viewed from the side surface shown in FIG. 21, the light distribution is omnidirectional in the XY plane around the light emitting point L0 of the arc tube 1, that is, a light distribution of 360 degrees.

  In this case, the outgoing light beam reflected from the reflection point 2c of the reflector 2 from the light emitting point L0, that is, the outgoing light beam reflected by the light reflecting surface located behind the arc tube 1 when viewed from the optical axis LA, Since the traveling direction changes on the outer surface of the glass tube 5 and the desired condensing point Sp cannot be reached, loss light is generated.

  Next, a light source device according to a second prior art will be described with reference to FIGS. FIG. 22 is a top view of an optical axis vertical arrangement type light source device according to an example of the second prior art in which the reflecting surface of the reflector is a concentric circular surface and a condenser lens is arranged, and FIG. FIG.

  The light source device shown in FIGS. 22 and 23 is the same as the light source device shown in FIGS. 20 and 21 except that the reflecting surface 10a of the reflector 10 is a spherical surface and the condenser lens 11 is disposed. Here, the same reference numerals are given to the equivalents thereof, and detailed description thereof is omitted.

The configuration of the light source device shown in FIG. 22 is the same as that of the reflector 10 positioned rearward of the arc tube 1 when viewed from the optical axis LA in the light source device of the optical axis vertical arrangement type according to the first prior art (shown in FIG. 20). The reflecting surface 10a is a spherical surface centered on the light emitting point L0, and the condenser lens 11 is disposed in front of the arc tube 1 when viewed from the optical axis LA.
In this configuration, the outgoing light emitted from the arc tube 1 is emitted from the light emitting point L0 toward the condenser lens 11 with a light distribution of an angle θ2 (same as θlamp in FIG. 18).

The light is emitted from the light emitting point L0 to the reflector 10 side at an emission angle of θ2. Ideally, the light passes through the light emitting point L0 again, and is emitted toward the condenser lens 11 side with a light emission distribution of angle θ2. At this time, the condensing lens 11 is designed on the basis of the light distribution of the arc tube 1. The condensing lens 11 condenses the light beam having the divergence angle of the angle θ 2, and the outgoing light beam incident on the incident point 11 a of the condensing lens 11 is It reaches the condensing point Sp.
In FIG. 22, it seems that most of the emitted light rays reach the predetermined condensing point Sp. However, when the side view shown in FIG. 23 is viewed, the emitted light from the arc tube is centered on the light emitting point L0 and is XY. The light distribution in all directions of the surface, that is, 360 degrees.

At this time, the light emitted from the arc tube 1 includes a component that is directly irradiated on the lens 11 side at an emission angle of 180 ° from the light emission point L0 and a reflection on the concentric surface of the reflector 10 at an emission angle of 180 ° directly from the emission point. There is a component that irradiates the surface 10a side and ideally passes through the light emitting point L0 again and irradiates the condenser lens 11 side.
Of these outgoing rays, the outgoing rays incident on the condensing lens 11 reach the condensing point Sp only by the spread angle of the angle θ2, that is, the light rays incident on the effective diameter of the condensing lens 11.
Japanese Patent Laid-Open No. 2-55325 Japanese Patent Laid-Open No. 4-242064 JP-A-6-214115

  However, in the optical axis vertical arrangement type light source device shown as the first prior art, in the system in which the reflecting surface of the reflector is an aspherical surface such as an elliptical surface or a hyperboloid, the reflector out of the outgoing light emitted from the arc tube The component that does not irradiate the aspherical reflecting surface cannot reach the desired condensing point or region, and the light capture efficiency decreases.

  Further, in the light source device of the optical axis vertical arrangement type shown as the second prior art, the reflection surface of the reflector behind the arc tube is a concentric surface when viewed from the optical axis, and the light emission is viewed from the optical axis. In the method in which a condensing element such as a lens is arranged in front of the tube, there is a limit to the angle at which the emitted light is captured when the condensing element captures the emitted light from the arc tube and its concentric reflecting surface. Even in this case, there is a problem in that the light capturing efficiency is lowered.

  The present invention solves the above-mentioned problems, and can improve the light collection efficiency to a predetermined small-diameter region while having a simple and compact configuration, and thus causes a reduction in light capture efficiency. It is an object of the present invention to provide a light source device and a video display device that are free from problems.

In order to achieve the above object, the configuration of the light source device and the image display device according to the present invention is as follows.
According to the present invention, there is provided an arc tube in which a pair of main electrodes are arranged on one electrode axis, and leads of the main electrodes are sealed with a sealing portion, and a reflector for reflecting the emitted light emitted from the arc tube In the light source device having the electrode axes of the main electrodes intersecting with the optical axis of the emitted light, the reflector is made of a metal base material, and is made of a spherical surface centering on the light emitting point of the arc tube. And a second reflector portion having an elliptical surface in front of the arc tube, and the reflected light reaches a predetermined condensing point by the first and second reflector portions. And a lens for condensing the emitted light emitted from the arc tube toward the part other than the second reflector part and irradiating the light in a predetermined direction or region is provided inside the second reflector part, and The arc tube sealing portion and the first A light source device and a reflector portion and a second reflector portion, characterized in that fixed through the heat dissipation material.
In the present invention, an inclusion having a different material from the heat dissipating material is interposed between the sealing portion of the arc tube and the heat dissipating material or between the first reflector portion and the second reflector portion and the heat dissipating material. Is preferred.
In addition, it is preferable to use a sealed light source in which a tapered cone extends to the tip of the second reflector portion, and the tip of the cone opens near the predetermined condensing point.
The present invention is a video display device using any of the light source devices described above.

  According to the present invention, the reflector is made of a metal base material, and the first reflector portion made of a spherical surface centering on the light emitting point of the arc tube, and the second elliptical surface forward from the arc tube. The first and second reflector parts are configured to cause the reflected light to reach a predetermined condensing point, and from the arc tube to other than the second reflector part. Since the lens for condensing the emitted light emitted in this manner and irradiating the region in a predetermined direction or region is provided inside the second reflector unit, the light is condensed to a desired small-diameter region by a simple configuration of the lifter and the lens. Efficiency can be increased. In other words, the light emitted from the light emitting point of the arc tube can be used efficiently.

  In addition, since the second reflector portion is an ellipsoidal surface, the focal length can be shortened, and the imaging magnification can be designed to be small. Can contribute to downsizing.

  In addition, since a lens for condensing the emitted light emitted from the arc tube toward the part other than the second reflector part and irradiating it in a predetermined direction or region is provided inside the second reflector part, the light emitted from the light source is provided. The utilization efficiency of the incident light can be increased.

In addition, a sealed portion is formed by sealing the main electrode on both sides of the luminous point of the arc tube, and a heat dissipating material is disposed between the sealed portion and the reflector, so that the final assembled product is obtained. Even if there is no work such as the alignment of the optical axis of the light source device and the illuminance equalizing means, it is possible to efficiently irradiate the light beam emitted from the arc tube to the screen, improving the light utilization efficiency, and finally This is effective in preventing variations in the illuminance for each assembly unit.
In addition, the temperature of the arc tube itself during continuous lighting can be optimally controlled, and the auxiliary electrode can be installed in a region outside the light distribution distribution of the discharge tube, thereby hindering the utilization efficiency of the emitted light emitted from the light source. There is no.

  Embodiments of the present invention will be described below with reference to FIGS. First, a light source device according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan sectional view showing a basic configuration of a light source device according to a first embodiment of the present invention, and FIG. 2 is a side sectional view of the light source device.

  As shown in FIG. 1, the light source device B according to the first embodiment of the present invention includes an arc tube 20 that is a light source, a reflector 30 that reflects the emitted light emitted from the arc tube 20, and a light collector 40. It has the composition which has.

Although the arc tube 20 has the same configuration as the arc tube 1 described above, the configuration will be described in more detail.
The arc tube 20 is a direct-current lighting type high-pressure mercury lamp having a diameter of about 10 (mm), in which an anode electrode 21 and a cathode electrode 22 as a pair of main electrodes are enclosed in a glass tube 23. In addition, the input power of the arc tube is 150 (W) to 200 (W). Reference numeral 23a denotes a sealed portion in which the anode electrode side lead rod 24 is sealed, and reference numeral 23b denotes a sealed portion in which the cathode electrode side lead rod 27 is sealed.

  For the purpose of activating electron emission, the cathode electrode 22 is formed with a protruding portion 22a having a higher work function and a coiled portion 22b for controlling the work function and controlling electron emission.

  The glass tube 23 is made of quartz having a heat resistance of 1000 (° C.) or higher, and in the sealed space of the light emitting point L0, mercury for adjusting the vapor pressure, and a starting gas such as argon gas and xenon gas. Is enclosed.

  The anode electrode 21 and the cathode electrode 22 coincide with one electrode axis O1 passing through the light emitting point L0 and are arranged on both sides of the light emitting point L0. The interelectrode distance (arc gap) between the anode electrode 21 and the cathode electrode 22 is about 1.0 (mm) to 1.3 (mm).

The arc tube 20 and a not-shown arc tube lighting control device (generally called “ballast”) are electrically connected to the anode electrode side lead rod 24 and the cathode electrode side lead rod 27 exposed to the outside from the glass tube 23. It is connected to the.
That is, at the start of lighting, a potential difference of several kv to several tens of kv is generated between the anode electrode 21 and the cathode electrode 22 to cause dielectric breakdown between the anode electrode 21 and the cathode electrode 22 to start glow discharge. Arc discharge occurs, and the state shifts to a stable lighting continuous state. Reference numerals 25 and 26 are molybdenum sheets welded to part of the anode electrode side lead rod 24 and the cathode electrode side lead rod 27.

The reflector 30 is for reflecting the emitted light emitted from the arc tube 20 in a predetermined direction. The reflector 30 includes a first reflector portion 31 having a spherical surface centering on the light emitting point L0 of the arc tube 20 and the first reflector portion 31. A first reflector portion 31 and a second reflector portion 32 having a different curved surface are formed.
In this embodiment, it is formed using an aluminum substrate having a thermal conductivity 200 times that of glass. Conventionally, the reflector is formed of a ceramic substrate in addition to the above heat-resistant glass substrate.

  The “curved surface different from the first reflector portion 31” is an elliptical surface in the present embodiment, but is not limited to this. For example, a spherical surface having a different curvature from the spherical surface of the first reflector portion 31 is used. Moreover, it may be composed of a curved surface other than a spherical surface such as a hyperboloid.

  A light source arrangement groove 33 with a required interval W is formed between the first reflector part 31 and the second reflector part 32, and the arc tube 20 is arranged here. The “required interval W” is such that a gap is formed between the sealed portions 23 a and 23 b of the arc tube 20, and can be set in consideration of the degree of heat radiation of the arc tube 20.

A light reflecting surface for reflecting the light emitted from the arc tube 20, specifically, the first reflector portion 31 and the second reflector portion 32, is a dielectric reflecting film made of a laminated film of TiO ₂ and SiO _2. (Not shown).
That is, in consideration of heat dissipation measures for the reflector 30, a layer that thermally converts infrared components with anodized oxide, chrome plating, black paint, or the like is provided to efficiently absorb and radiate heat to the reflector 30. After applying a base coat for buffering and flattening on the layer to be converted into heat, a dielectric reflective multilayer film made of TiO ₂ and SiO ₂ is formed to allow visible light to reach a predetermined condensing point.

  In the present embodiment, the heat of the arc tube 20 during continuous lighting is absorbed and radiated by the reflector 30. However, the present invention is not limited to this, and the reflective surface of the metal substrate may be simply polished. Further, by forming a total reflection film of silver and aluminum and an image reflection film on a metal substrate, ultraviolet rays and infrared rays may be separately absorbed or emitted.

Next, the positional relationship between the reflector 30 and the arc tube 20 will be described.
The electrode axis O1 of the anode electrode 21 and the cathode electrode 22 of the arc tube 20 is arranged substantially orthogonal to the optical axis LA. In this case, the ellipsoidal reflecting surface (second reflector portion 32) is defined by the following equation, with the light emitting point L0 of the arc tube 20 as the first focal point F1 and the predetermined condensing point Sp as the second focal point F2. Designing.

The symbols shown in the following equations (1) to (4) are the coordinates of a point on the ellipse circumference in the XY coordinates, and a is the ellipse major axis (X = 0), b is the length of the ellipse minor axis (Y = 0), and e is the eccentricity of the ellipse.
x ² / a ² + y ² / b ² = 1 (1)
e = (a ² −b ² ) ^1/2 / a (2)
F1 = a × e = L0 (3)
F2 = (− a) × e = Sp (4)

  Of the emitted light emitted from the light emitting point L0 of the arc tube 20, the component that does not irradiate the second reflector 32, that is, the collected light that causes the emitted light in the region of the spread angle of the angle θ1 to reach the desired condensing point Sp. The effective diameter of the lens 40 as a light body is designed.

Next, the light source device according to Reference Example 1 will be described with reference to FIG. FIG. 3 is a plan sectional view of the light source device according to Reference Example 1.
Since the light source device C according to the reference example 1 has the same configuration as the light source device B according to the first embodiment described above except for the configuration of the reflector, the same components are denoted by the same reference numerals. Detailed description is omitted here, and only reflectors having different configurations will be described here.

The reflector 50 according to the reference example 1 includes a first reflector portion 41 having a spherical surface centered on the light emitting point L0 of the arc tube 20, and a second reflector portion 42 having a curved surface different from the first reflector portion 41. Is the same as that of the reflector 30.
In the reflector 50 according to the first reference example, the “curved surface different from the first reflector portion 41” is a hyperboloid (parabolic surface).

That is, of the light emitted from the light emitting point L0 of the arc tube 20, the component reflected by the second reflector unit 42 becomes a light beam substantially parallel to the optical axis LA, and is applied to the predetermined region Sp. At this time, if the lens 40 is not incorporated, most of the emitted light beams that are emitted from the arc tube 20 at the angle θ1 shown in FIG. 3 and are not irradiated to the second reflector portion 42 do not reach the predetermined region Sp. It becomes light. In other words, in Reference Example 1, no loss light is generated because the lens 40 is disposed.
As shown in Reference Example 1, when the second reflector portion 42 is a hyperboloid, the light source device and the optical path of the predetermined region are fly over in order to improve the illuminance unevenness of the predetermined region Sp. An array or the like may be arranged.

FIG. 4A is a plan sectional view showing an example of a specific lens mechanism that supports a lens provided in the light source device according to the first embodiment of the present invention, and FIG. 4B is a front view of only the lens mechanism. FIG. 5A is a plan sectional view showing another example of the specific lens mechanism described above, and FIG. 5B is a front view of only the lens mechanism according to the other example. FIG. 6 is a plan sectional view for explaining the behavior of the emitted light emitted from the arc tube of the light source device according to the first embodiment of the present invention and the location of the collector.
4 to 6, the same components as those described in the light source device B according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

The lens mechanism 41, which is a condensing body shown in FIG. 4, does not irradiate the second reflector 32 (components other than the group of rays irradiating the second reflector 32 indicated by the dotted line area in FIG. 6). And a doughnut-shaped lens 41b in which a hole corresponding to the diameter of the lens 41a is formed at the center of a flat substrate.
The biconvex lens 41a and the donut-shaped lens 41b are fitted with a heat-resistant adhesive while the biconvex lens 41a is fitted into the hole 41a 'of the donut-shaped lens 41b.
The lens mechanism 41 is fixed by fitting the outer peripheral edge of the donut-shaped lens 42b into a fitting groove 32a formed at a predetermined position of the second reflector 32 over the entire circumference.

  A lens mechanism (condenser) 43 according to another example shown in FIG. 5 includes lens holding members 43a and 43a and a lens 40 supported between the open ends of these lens holding members 43a and 43a.

The lens holding members 43a and 43a are formed such that the base end portion is fixed to the second reflector portion 32 and both open end portions face each other at a predetermined interval.
According to this configuration, if the light distribution of the arc tube 20 is θ1 (see θlamp shown in FIG. 18), the effective diameter of the lens 40 is made larger than θ1, thereby allowing the outgoing light rays to be transmitted to the lens holding members 43a and 43a. There is no irradiation, and the utilization efficiency of the emitted light emitted from the light source is not reduced. The lens holding members 43a and 43a may not be formed integrally with the second reflector portion 32.

Next, the lens installation method will be described with reference to FIG. The behavior of the emitted light is symmetrical only in the upward direction (+ Y direction) and the downward direction (−Y direction) with respect to the optical axis LA.
Of the emitted light emitted from the light emitting point L0 of the arc tube 20, the light reflected by the first reflector portion 31 behind the arc tube 20 as viewed from the optical axis LA passes through the light emitting point L0 again, and the optical axis LA. The light exits from the arc tube 20 as viewed from the front.

  At this time, out of the emitted light beams emitted in front of the arc tube 20 as viewed from the optical axis LA, the light beam (L0-a) irradiated to the innermost part of the second reflector unit 32 and the second reflector unit 32 thereof. The second reflector 32 is irradiated with a light beam passing through an angle (a-L0-b) formed by a light beam (L0-b) irradiated to the outermost part (near the opening).

The light beam (L0-a) that irradiates the innermost part of the second reflector part 32 and the light beam (L0-b) that irradiates the outermost part (near the opening) of the second reflector part 32 are second reflectors. The condensing point Sp that is the second focus of the unit 32 is irradiated.
When the lens 40 is not provided, most of the light beam in the angle range formed by b-L0-Sp is not irradiated onto the second reflector unit 32. Here, an outgoing ray (L0-b) that is emitted from the light emitting point L0 of the arc tube 20 and irradiates the outermost part (near the opening) of the second reflector 32, and a point of the second reflector 32. When the point where the light rays (a-Sp) reflected by the crossing point is c and the principal point H of the lens 40 (assuming a thin lens) is taken on the optical axis LA, the effective radius of the lens arranged by the length of cH. It becomes.

FIG. 7 is an explanatory diagram of the focal length of the lens and the imaging magnification.
When the light emitting point L0 of the arc tube 20 is an object plane having an image height y, and the condensing point Sp is an image plane having an image height yd, the front focal point of the lens 40 to be arranged is F, the rear focal point is Fd, The front radius of curvature R1 and the rear radius of curvature R2 of the lens are f, the distance from the principal point H to the front focal point F and the distance from the principal point H to the rear focal point Fd are f, and from the front focal point F to the object plane. When the distance is Z and the distance from the rear focal point Fd to the image plane Sp is Zd, the lens is designed so that the following relationship is established.

1 / f = (N−1) [(1 / R1) + (1 / R2)]
Where N is the refractive index of the lens glass material y / yd = Z / f (5)
y / yd = f / Zd (6)
Here, if the imaging magnification M = yd / y,
Z = f / M (7)
Zd = f × M (8)
Further, when C−L0−Sp = U (take-in angle), C−Sp−L0 = Ud (condensing angle), and C−H = h,
U = h / [(1 + 1 / M) × f] (9)
Ud = h / [(1 + M) × f] (10)
From equations (9) and (10),
U / Ud = (1 + M) / (1 + 1 / M) = M (1 + M) / (1 + M)
= M
= Yd / y (11)

Here, the arc gap of the high-pressure mercury lamp used in each embodiment is 1.05 (mm), and the lens integrator has an entrance surface dimension of 3.0 × 4.0 (mm), and the lens The imaging magnification of 40 was designed between 2.5 and 4. The lens glass material used was quartz, and its refractive index was set to a curvature of the lens 40 from 1.46.
As shown in FIG. 3, when the second reflector portion 42 is a hyperboloid, the lens 40 is set at the principal point H as described above, and the light emitted from the arc tube 20 is incident on the lens 40. It is only necessary to design so as to irradiate almost perpendicularly to the predetermined region Sp (substantially parallel to the optical axis LA).

FIG. 8 shows the utilization efficiency result of the emitted light emitted from the light source when the diagonal dimension of the predetermined region in the present invention is varied. FIG. 8 is a comparison diagram showing the results of the utilization efficiency of the emitted light emitted from the light source when the diagonal dimension of the predetermined region is varied.
In the figure, “black circle” indicates the present invention, and “black triangle” indicates a conventional arrangement in which the electrode axis of the arc tube is arranged in parallel to the optical axis in practical use, and the reflector has an elliptical reflecting surface. The light source device, “black square”, is a light source device (first prior art) including a reflector in which the electrode axis of the arc tube is arranged substantially orthogonal to the previously proposed optical axis, and is an ellipsoid. “X” indicates a light source device (second prior art) in which the electrode axis of the arc tube is arranged substantially orthogonal to the optical axis, the reflector has a spherical reflecting surface, and a lens is provided.

  As design conditions, the arc gap of the arc tube was 1.05 (mm), the maximum emission angle of light from the opening of the light source device was 30 °, and the distance from the light source to the condensing point was within 50 (mm). The aperture diameter of the reflector and the effective lens diameter were set to 40 (mm) or less.

In the prior art (shown by black triangles), a light beam is applied to the sealing portion of the arc tube located in the direction of the optical axis to generate loss light, but the utilization efficiency of the emitted light emitted from the light source is first. Higher than the light source device of the second prior art.
In the first prior art, only the light beam reflected mainly by the ellipsoidal surface of the reflector can be captured, and the light source of the present invention is used when the diagonal dimension of the desired condensing point Sp is between 5 and 10 (mm). There is 10% loss light compared to the device.

Regarding the second prior art, it is unsuitable for irradiation to a minute condensing point, and the utilization efficiency of the emitted light emitted from the light source when the diagonal size of the desired condensing point Sp is 10 (mm) is It was about 20 (%).
As the second prior art lens, a glass material having a refractive index of 1.46 to 1.98 was used for estimation. FIG. 8 shows data when the refractive index is 1.98. As a glass material that does not deteriorate in a high-temperature atmosphere near the arc tube, there are quartz and synthetic quartz, and the refractive index is 1.46. Furthermore, the utilization efficiency of the emitted light emitted from the light source is lowered. Other glass materials include sapphire (refractive index 1.77) and diamond (refractive index 2.4), but they are not practical because they are expensive.

  In the light source device B according to the first embodiment, the utilization efficiency of the emitted light emitted from the light source equivalent to the light source device according to the prior art that has been put into practical use is obtained, and the size of the desired region is small. In some cases, the utilization efficiency of the emitted light emitted from the light source can be improved by 10 (%) as compared with the prior art.

Next, a light source device D according to a second embodiment of the present invention will be described with reference to FIG.
FIG. 9 is a plan sectional view showing a basic configuration of a light source device D according to the second embodiment of the present invention.
The light source device D according to the second embodiment has the same configuration as that of the light source device according to the first embodiment described above except for the configuration of the reflector. Thus, detailed description is omitted, and only reflectors having different configurations will be described here.

The reflector 44 includes a first reflector portion 45 formed of a spherical surface centered on the light emitting point L0 of the arc tube 20 and a second reflector portion 46 formed of a curved surface different from the first reflector portion 45, and illuminance uniformizing means. 44a is integrally formed.
The “curved surface different from the first reflector portion 45” is an elliptical surface in the present embodiment.

  A light source arrangement groove 47 having a required interval W is formed between the first reflector part 45 and the second reflector part 46, and the arc tube 20 is arranged here. The “required interval W” is such that a gap is formed between the sealed portions 23 a and 23 b of the arc tube 20 and can be set in consideration of the degree of heat radiation of the arc tube 20. As described above.

  That is, the reflector 44 has a path d-Sp when the outgoing ray traveling along the path L0-d-Sp has the maximum outgoing angle (the angle formed by L0-Sp-d) among the outgoing rays irradiating the reflector 44. The conical body is continuously extended from the front opening of the second reflector portion 46 of the reflector 44 so as not to obstruct the path of the outgoing light beam, and is connected to the illuminance equalizing means 44a in the vicinity of the condensing point Sp. The structure is integrally formed.

The illuminance uniforming means 44a has a function of uniformizing (flattening) the surface illuminance of the light beam by shaping the outgoing light emitted from the arc tube 20 into a target shape and mixing with multiple reflections. The reflector 44 is formed in a cylindrical shape having a required length at the front end portion (frontmost portion).
In other words, the light emitted from the light source has a function of uniformizing the surface illuminance of the light beam by shaping the emitted light into a target shape and mixing it by multiple reflection (mixing mechanism).
The “target shape” means a similar shape of a light valve (here, DMD shape = square).

The aperture shape of the illuminance equalizing means 44a is determined by the image forming magnification determined from the exit angle from the light source device, the region of the light valve 106, and the incident angle in the projection display apparatus shown in FIG. Is.
The inner surface of the illuminance uniforming means 44a can be a mixing mechanism formed as follows.
As in the case of the second reflector portion 46 and the first reflector portion 45, the infrared component heat conversion layer, the planarization layer, and the dielectric reflection multilayer film made of ТiO ₂ and SiO ₂ are formed.
In addition to the dielectric reflective multilayer film, a configuration in which an aluminum base material (metal base material) is simply polished or a total reflection film deposition of silver or the like and an increased reflection film may be applied to the aluminum base material.

Further, by incorporating a lens rod integrator into the inner surface of the illuminance uniforming means 44a, it is not necessary to perform a film forming process on the inner surface of the illuminance uniforming means 44a, and an explosion-proof mechanism can be easily realized.
Furthermore, the use efficiency of the emitted light emitted from the light source can be improved by using a glass material that converts ultraviolet rays or infrared rays such as fluorite into visible rays as the lens rod integrator.

A light source device E according to a third embodiment will be described with reference to FIG. FIG. 10 is a plan sectional view of a light source device E according to the third embodiment.
The light source device E according to the third embodiment has the same configuration as that of the light source device according to the second embodiment described above except that a heat dissipating material is provided. A detailed description will be omitted with reference numerals, and only the heat dissipating material will be described here.

  The heat dissipating materials 60 and 60 have an inner diameter that substantially matches the outer diameter of the sealing portions 23a and 23b, an outer diameter that substantially matches the gap W of the reflector 44, and faces the sealing portion 23a (23b). One end of the reflector 44 is slanted so as to have lengths L1 and L2 according to the length of the wall surface, or is simply a cylindrical shape having a length L1, and has good heat conductivity. (Alumina) -containing material or cement. In addition, when a gap is generated between the reflector 44 and the heat dissipating materials 60 and 60, and the sealing portions 23a and 23b and the heat dissipating materials 60 and 60, heat-resistant cement, grease, or oil compound is filled in the gap as necessary. That's fine.

  As a result, the temperature of the arc tube 20 itself during continuous lighting can be efficiently conducted to the reflector 44, so that temperature control that enables optimal lighting of the arc tube 20 is possible. In addition, of course, such a heat radiating material is applicable to the light source device which concerns on each embodiment etc. which were demonstrated in FIGS.

A light source device F according to a fourth embodiment will be described with reference to FIG. FIG. 11 is a cross-sectional plan view of a light source device F according to the fourth embodiment.
The light source device F according to the fourth embodiment has the same configuration as that of the light source device according to the third embodiment described above except that the auxiliary electrode is provided and the reflector is grounded. The same reference numerals are attached to the same components and detailed description thereof is omitted, and only the differences will be described here.

  The auxiliary electrodes 61, 61 are ring-shaped surrounding the proximal end sides of the sealing portions 23 a, 23 b of the arc tube 20, and are conductively connected in the vicinity of both end edges of the first reflector portion 45 of the reflector 44. . As a result, the startability of the arc tube 20 can be improved and the auxiliary electrode can be formed in a space other than the light distribution of the arc tube 20, thereby obstructing the utilization efficiency of the emitted light emitted from the light source. There is no.

A light source device G according to a fifth embodiment will be described with reference to FIG. FIG. 12 is a plan sectional view of a light source device G according to the fifth embodiment.
The light source device G according to the fifth embodiment has the same configuration as that of the light source device according to the fourth embodiment described above except that the auxiliary electrode is formed integrally with the reflector. The same reference numerals are assigned to the components, and detailed description thereof is omitted, and only differences will be described here.

In the vicinity of both end edges of the first reflector portion 45 of the reflector 44, rectangular parallelepiped auxiliary electrode members 48, 48 having a required length are integrally formed to project.
The auxiliary electrode members 48, 48 are formed with circular fitting holes 48 a, 48 a that match the outer diameter of the sealing portions 23 a, 23 b of the arc tube 20. As a result, the startability of the arc tube 20 can be improved and the auxiliary electrode can be formed in a space other than the light distribution of the arc tube 20, thereby obstructing the utilization efficiency of the emitted light emitted from the light source. The absence of this is the same as in the fourth embodiment described above.

With reference to FIGS. 13-15, each example of the reflector in the light source device which concerns on embodiment of this invention is demonstrated.
FIG. 13 is a schematic diagram of the reflector according to the first example, FIG. 14A is a schematic plan sectional view of the reflector according to the second example, and FIG. 13B is a line II shown in FIG. FIG. 15 is a schematic cross-sectional view of a reflector according to a third example, and FIG. 15B is a cross-sectional view taken along line II-II shown in FIG.

  A reflector 70 according to the first example shown in FIG. 13 includes a reflector segment 71 formed with a first reflector portion 71a having a spherical surface centered on the light emitting point L0 of the arc tube 20, and the first reflector portion. It consists of the reflector division body 72 in which the 2nd reflector part 72a which consists of a curved surface different from 71a was formed.

The reflector divided bodies 71 and 72 can be divided on the plane including the electrode axis O1. That is, it is structured to be divided into a reflector divided body 71 and a reflector divided body 72 in a direction orthogonal to the optical axis LA.
A flange 71b formed with a bolt loose insertion hole 71c is formed on the dividing surface of the reflector divided body 71, and a flange 72b formed with a bolt screwing hole 72c is formed on the divided surface of the reflector divided body 72 so as to protrude. In addition, it can be easily connected and separated by bolts or the like through the flanges 71b and 72b.

In this embodiment, it is screwed by a bolt (screw) of the same quality as the base material of the lift creter 70. This is because, when bolts (screws) of different materials are used, the coefficients of thermal expansion are different, so that distortion and screw breakage occur. That is, distortion and screw breakage are prevented by being screwed together with bolts (screws) of the same quality as the base material of the lift creter 70.
As other configurations, it is possible to provide a concavity and convexity to be coupled so that the reflector divided bodies are simply fitted with each other, and a separate holding mechanism is provided to fix both.

The “curved surface different from the first reflector portion 71a” is an ellipsoidal surface, but may be a spherical surface having a different curvature from the spherical surface of the first reflector portion 71a, or a curved surface other than a spherical surface such as a hyperboloid. It may be.
When depositing a vapor deposition film on a composite reflector, the thickness and density of the film stack are nonuniform due to the difference in curvature, the flight distance of the vapor deposition molecules, and the incident angle of the vapor deposition molecules on the film formation surface. For this reason, in the reflector 70 shown in FIG. 13, it divides | segments in the reflective surface unit of the same curvature, and it forms each vapor deposition condition in a concentric-circular surface part and an elliptical surface part, and forms the film of the reflectance of a visible light region. A good reflector can be realized, and the utilization efficiency of the emitted light emitted from the light source can be improved.

  A reflector 80 according to the second example shown in FIGS. 14A and 14B includes an upper half portion 82a of the first reflector portion 82 formed of a spherical surface centered on the light emitting point L0 of the arc tube 20 and the first half thereof. The upper reflector divided body 81 formed with the upper half portion 83a of the second reflector portion 83 having a curved surface different from that of the reflector portion 82, and the first reflector made of a spherical surface centering on the light emitting point L0 of the arc tube 20. It comprises a lower half portion 82b of the portion 82 and a lower reflector divided body 84 formed with a lower half portion 83b of the second reflector portion 83 having a curved surface different from that of the first reflector portion 82.

In other words, the reflector 80 is divided in parallel with the optical axis LA. Such a divided structure is particularly effective for a reflector having a small size and a long depth.
However, the angle θsa formed by the straight line S0-e connecting the deposition source So and the position e of the reflective film forming surface and the normal line of the reflective film forming surface is relatively large. This means that the incident angle of the vapor deposition molecules to the position e of the reflecting film forming surface is large, and the adhesion of the film to this portion is not as good as the position f of the reflecting film forming surface.

The reflector 90 according to the third example includes four reflector divided bodies 91 to 94 that are divided at intervals of 90 degrees around the optical axis LA.
Each reflector divided body 91 (92 to 94) is formed of a quadrant 95a of the first reflector portion 95 which is a spherical surface centering on the light emitting point L0 of the arc tube 20 and a curved surface different from the first reflector portion 95. A quarter portion 96 a of the second reflector portion 96 is formed.

In this way, by increasing the number of reflector divisions (number of divisions), the flight distance of the vapor deposition molecules from the vapor deposition source S0 to the positions g, h, i on the reflective film forming surface becomes uniform. The incident angle can be made uniform.
The film formation result at the position i on the reflection film formation surface was twice as accurate as the reflection film formation surface j shown in FIG. In addition, since the divided reflector segments are formed in the same shape, a large number of reflector segments can be formed by a single vapor deposition batch process. Therefore, the segmented structure is not different from the conventional one in terms of cost.

  Next, a video display device using the light source device according to each of the above embodiments will be described with reference to FIG. FIG. 16 is a schematic diagram showing a schematic configuration of a video display apparatus according to an embodiment of the present invention. FIG. 16 shows an example in which the light source device B shown in FIG. 1 is used, but instead of the light source device B, light source devices C, D, E, F, and G can be adopted. .

An image display device H according to an embodiment of the present invention includes a light source device B, a color wheel 100, a rod integrator 101, lenses 102 to 104, a mirror 105, a light valve 106, and a projection lens 107. Reference numeral 108 denotes a screen.
The outgoing light emitted from the arc tube 20 of the light source device B is reflected by the reflector 30 and collected on the incident surface of the rod integrator 101.

  In the color wheel 100, an R (red: red) filter, a G (green: green) filter, and a B (blue: blue) filter are arranged in a disc shape in front of the entrance surface of the rod integrator P4. Is formed.

  The rod integrator 101 emits incident light incident thereon to a light beam having a desired cross-sectional shape corresponding to the planar shape (in this case, rectangular or square) of the light valve 106 and having a uniform illuminance at each part. .

  As the color wheel 100 rotates, the reflected light from the reflector 30 passes through the filters R, G, and B, and the transmitted light corresponding to the colors of the filters R, G, and B sequentially enters the rod integrator 101. To do.

  The light valve 106 is a projection medium that forms a projected image, and is configured using a DMD (Digital Micro-mirror Device). In the case of DMD, a mirror for each minute section controls the reflection direction according to a desired projection image, and forms a projection light image of each color light formed by each filter R, G, B.

The rod integrator 101 makes the illuminance of the desired surface uniform by the rod integrator 101, travels through the optical system of the lenses 102 to 104 and the mirror 105, enters the light valve 106, and forms a projected light image.
The projection light image formed by the light valve 106 passes through the projection lens 107 and is projected onto the screen 108 to project an image.

Note that the present invention is not limited to the above-described embodiments, and the following modifications are possible.
The light source device according to each of the above-described embodiments has been described as a light source device used for a projection video display device, but is not limited thereto, and can be used as a light source for other devices.
Further, the projection type image display apparatus is not limited to the one shown in FIG. 16, but the light source apparatus according to each embodiment of the present invention may be used even if the optical path is different or the light valve 106 is a liquid crystal. Can be applied.

  The present invention is a high-luminance light source device using an arc tube that performs illumination by generating arc discharge, such as a metal halide lamp, a xenon short arc lamp, or a high-pressure mercury lamp, and has a simple and compact configuration. However, it is possible to increase the light collection efficiency in a predetermined small-diameter region, and therefore, a light source device that does not cause a decrease in light capture efficiency and a projection display device that requires such a light source device with high brightness. Can be used.

It is a plane sectional view showing the basic composition of the light source device concerning a 1st embodiment of the present invention. It is a sectional side view of a light source device same as the above. It is a plane sectional view of the light source device according to Reference Example 1. (A) is a plane sectional view showing an example of a specific lens mechanism for supporting a lens provided in the light source device according to the first embodiment of the present invention, and (b) is a front view of only the lens mechanism. . (A) is a plane sectional view showing another example of a specific lens mechanism, and (b) is a front view of only a lens mechanism according to another example. It is a cross-sectional view for explaining the behavior of the emitted light emitted from the arc tube of the light source device according to the first embodiment of the present invention and the location of the collector. It is explanatory drawing of the focal distance and imaging magnification of a lens. It is a comparison figure which shows the result of the utilization efficiency of the emitted light radiate | emitted from the light source at the time of changing the diagonal dimension of a predetermined area | region. It is a plane sectional view showing the basic composition of the light source device concerning a 2nd embodiment of the present invention. It is a plane sectional view of the light source device which concerns on the 3rd Embodiment of this invention. It is a plane sectional view of the light source device concerning a 4th embodiment of the present invention. It is a plane sectional view of the light source device concerning a 5th embodiment of the present invention. It is the schematic of the 1st example of the reflector in the light source device which concerns on embodiment of this invention. (A) is a schematic plane sectional view of the 2nd example of the reflector in the light source device which concerns on embodiment, (b) is sectional drawing which follows the II line | wire shown to (a). (A) is a schematic plane sectional view of the 3rd example of the reflector in the light source device which concerns on embodiment, (b) is sectional drawing which follows the II-II line shown to (a). 1 is a schematic diagram illustrating a schematic configuration of a video display device according to an embodiment of the present invention. (A), (b) is a comparison explanatory drawing of the arrangement direction of an arc_tube | light_emitting_tube. It is a plane cross section which shows schematic structure of the light source device of an optical axis parallel arrangement type. It is a plane cross section which shows the behavior of the emitted light radiate | emitted from the light emission point of the optical axis parallel arrangement type light source apparatus shown in FIG. It is a top view of the optical axis perpendicular arrangement type light source device concerning an example of the 1st prior art which made the reflective surface of a reflector elliptical. It is a side view of the light source device which concerns on the other example of the 1st prior art which made the light reflection surface of the reflector the ellipse surface, and has arrange | positioned the electrode axis of the arc_tube | light_emitting_tube substantially perpendicularly with respect to the optical axis. FIG. 6 is a top view of a light source device of an optical axis vertical arrangement type according to an example of a second prior art in which a reflecting surface of a reflector is a concentric circular surface and a condenser lens is arranged. It is a side view of a light source device same as the above.

Explanation of symbols

20 arc tube 21, 22 main electrode 23a, 23b sealing part 30, 44 reflector 31, 45 first reflector part 32, 46 second reflector part 40 lens (condenser)
44a Illuminance uniformizing means 60 Heat radiation material B, C, D, E, F, G Light source device O1 Electrode axis LA Optical axis L0 Light emission point H Video display device

Claims (4)

A pair of main electrodes is arranged on one electrode axis, and has an arc tube in which the leads of the main electrodes are sealed with a sealing portion, and a reflector that reflects the emitted light emitted from the arc tube. In the light source device in which the electrode axes of these main electrodes intersect the optical axis of the emitted light,
The reflector is made of a metal base material, and forms a first reflector portion made of a spherical surface centering on the light emitting point of the arc tube, and a second reflector portion made of an elliptical surface forward from the arc tube. The first and second reflector parts are configured to cause the reflected light to reach a predetermined condensing point,
A lens for condensing the emitted light emitted from the arc tube toward the part other than the second reflector part and irradiating the light in a predetermined direction or region is provided inside the second reflector part; and
A light source device characterized in that a sealing portion of the arc tube and the first reflector portion and the second reflector portion are fixed via a heat dissipating material.   An inclusion having a different material from that of the heat dissipation material is interposed between the sealing portion of the arc tube and the heat dissipation material, or between the first reflector portion and the second reflector portion and the heat dissipation material. The light source device according to claim 1.   3. A sealed light source in which a tapered cone extends at the tip of the second reflector portion, and the tip of the cone is opened near the predetermined condensing point. The light source device according to 1.   A video display device using the light source device according to any one of claims 1 to 3.

Images