JP2008102168A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector capable of making effective use of luminous flux from a light emitting tube and achieving compact and simple cooling. <P>SOLUTION: In the light source device 21 of a rear projection device 100, the luminous flux radiated to an opposite side to a main reflection mirror 75 is restored to the light emitting portion of the main body part 73a of the light emitting tube 73 by a sub reflection mirror 77, so that the efficiency of using the luminous flux is enhanced. Furthermore, since a first fixing portion 73b supporting the main reflection mirror 75 is arranged on the upside in a vertical direction, a milky part or a blackened part is hardly formed on the peripheral side surface of the main body part 73a. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a projector that projects an image formed by a liquid crystal display panel or the like illuminated by a light source device.

As a metal halide lamp that can be used as a light source of a projector, there is one in which a pipe for blowing is provided in a portion of a base that supports an upper end of an arc tube (see Patent Document 1). In this metal halide lamp, air is blown from the pipe toward the upper portion of the arc tube, and a protective film is provided at the lower portion of the arc tube to prevent overcooling of the lower portion.
JP-A-6-52837

However, in the metal halide lamp as described above, it is not possible to make full use of the light beam emitted from the arc tube, particularly the light beam diverging downward with a certain spread angle. Further, forced air cooling concentrated on the arc tube is premised, and the light source device becomes complicated, and in order to improve the performance and reliability of the lamp, cooling of other device portions is separately required.

Therefore, an object of the present invention is to provide a projector that can effectively utilize a light flux from an arc tube and can achieve a small and simple cooling.

In order to solve the above problems, a projector according to the present invention includes, as a light source device, (a) a main body portion that houses a pair of discharge electrode ends, and a conductive member that extends vertically upward from the main body portion and extends from one electrode end. An arc tube having a first fixed part for accommodating a member and a second fixed part for accommodating a conductive member extending vertically downward from the main body part and extending from the other electrode end; and (b)
A main reflecting mirror provided on the first fixed portion side of the arc tube and emitting a light beam emitted from the arc tube aligned in a predetermined direction; and (c) provided on the second fixed portion side of the arc tube. A sub-reflector that returns the light beam radiated from the opposite side of the main reflector to the light-emitting portion in the main body of the arc tube, and (d) the horizontal direction by bending the light beam reflected by the main reflector in a direction orthogonal to each other And a reflecting member for guiding the light. In the above description, terms such as “vertically upward” and “vertically downward” are based on the direction of gravity when the projector is installed and operating.

In the projector described above, the luminous flux radiated to the opposite side of the main reflecting mirror by the sub-reflecting mirror is returned to the light emitting portion in the main body of the arc tube, so that the efficiency of using the luminous flux can be improved and the main reflecting mirror is supported. Since the 1st fixing | fixed part to perform is arrange | positioned at the upper side of a perpendicular direction, it can prevent that a cloudy part and a blackening part are formed in the surrounding side surface of the main-body part of an arc_tube | light_emitting_tube. In the light source device of the type provided with the sub-reflecting mirror, when the arc tube is disposed so as to extend in the horizontal direction, relative heating is performed among the peripheral side surfaces of the main body portion of the arc tube by heating with the return light from the sub-reflecting mirror. The cloudy part tends to be formed on the upper side where the temperature is high, and the blackened part tends to be formed on the lower side where the temperature is relatively low. Such a cloudy portion or a blackened portion reduces the light output, and particularly the cloudy portion may lead to damage to the arc tube. In any case, the lifetime of the arc tube is shortened.

According to a specific aspect or aspect of the invention, in the projector, the light source device further includes a collimating lens that collimates the light beam reflected by the main reflecting mirror and guides it to the reflecting member. In this case, parallel light can be incident on the next-stage uniformizing optical system or the like.

According to another aspect of the present invention, the reflecting member is a prism, the exit surface of the parallelizing lens is flat, and is adhered to the entrance surface of the prism. In this case, the optical path length can be shortened by the prism, and the collimating lens can be stably supported.

According to still another aspect of the present invention, there is further provided a ventilation portion that is provided around the first fixing portion and forms an air flow path between the lower surface and the upper surface of the upper part of the main reflecting mirror. In this case, the heat accumulated in the upper part of the main reflecting mirror can be exhausted upward, for example, as convection, and heating of the main reflecting mirror and arc tube can be prevented.

According to still another aspect of the present invention, the first fixing portion is fixed to the upper part of the main reflecting mirror via the fixing material, and the ventilation portion is a through hole formed in the fixing material. In this case, the through-hole can be easily formed using a fixing material for supporting the arc tube.

According to still another aspect of the present invention, an air cooling device is further provided that supplies a cooling airflow from vertically below toward the arc tube, the main reflecting mirror, and the sub-reflecting mirror. In this case, the arc tube, the main reflector, and the sub-reflector can be cooled as a whole by the air-cooling device. In particular, the main part of the arc tube can be prevented from being directly exposed to the cooling air by the sub-reflector. It becomes easy to keep the temperature of the main body portion stable.

According to still another aspect of the present invention, the main reflecting mirror has an elliptical type reflecting surface. In this case, the light beam can be efficiently collected by a relatively small mirror, and a light source device that is small and bright in the optical axis direction can be obtained.

According to still another aspect of the present invention, a light modulation unit that modulates a light beam emitted from a light source device according to input image information to form modulated light, and a modulated light from the light modulation unit as image light. As a projection optical system. In this case, the modulated light formed by the light modulation device can be projected onto the screen as image light. At this time, in the light source device, it is difficult to form a cloudy portion or a blackened portion on the peripheral side surface of the main body portion of the arc tube, so that a bright image can be projected for a long time, and the life of the light source device or the projector can be extended. .

According to still another aspect of the present invention, the light modulation unit includes a light modulation device for each color that modulates each color light, and separates the light beam emitted from the light source device into each color light to thereby output the light for each color. A color separation optical system that leads to the modulation device; and a color synthesis optical system that synthesizes the modulated light of each color modulated by the light modulation device for each color, and the projection optical system is synthesized by the color synthesis optical system. It is characterized by projecting image light. In this case, it is possible to project a color image obtained by combining the modulated lights of the respective colors formed by a plurality of light modulation devices.

[First Embodiment]
FIG. 1 is a side view illustrating the overall structure of the rear projection apparatus according to the first embodiment of the present invention. The rear projection apparatus 100 is realized as a television having various functions for displaying moving images and still images, and includes a projector main body 10 at the bottom of a case 12 that is a housing, and an upper rear side in the case 12. Includes a reflection mirror 16 and a case 12.
A transmissive screen 18 is provided on the front surface. Here, the projector body 10 is a body optical system for forming an image to be displayed on the rear projection apparatus 100. The image light emitted from the projector main body 10 travels obliquely upward and rearward substantially along the optical axis OA 1, is bent to the front side substantially along the optical axis OA 2 direction by the reflecting mirror 16, and is back on the transmissive screen 18. Incident from the side.

2 is a plan view for explaining the configuration of the optical system of the projector main body 10 incorporated in the rear projection apparatus 100 shown in FIG. 1, and FIG. 3 is a side view of the projector main body 10 of FIG.

The projector main body 10 shown in the figure is a light source device 21 that generates light source light, a color separation optical system 23 that separates the light source light from the light source device 21 into three colors of red, green, and blue, and a color separation optical system as basic parts of the projector. A light modulation unit 25 illuminated by illumination light of each color emitted from 23, a cross dichroic prism 27 that combines image light of each color from the light modulation unit 25, and image light that has passed through the cross dichroic prism 27 is transmitted through a screen. 18 (see FIG. 1) and a projection lens 29 which is a projection optical system for projecting.

In the projector main body 10 described above, the light source device 21 includes a light source lamp 21a, a collimating lens 21b, a reflecting member 21c, a pair of lens arrays 21d and 21e, a polarization conversion member 21g, and a superimposing lens 21i.

4A is a side sectional view of the light source lamp 21a, and FIG.
It is a partial top view of the upper part of a. The light source lamp 21a includes an arc tube 73 that is a lamp body, a main reflecting mirror 75 that is an elliptical reflector, and a sub-reflecting mirror 77 that is a spherical reflector.
Among the light source lamps 21a, the arc tube 73 is a discharge tube such as a high-pressure mercury lamp that emits light source light using discharge. Further, the reflecting mirrors 75 and 77 condense the light source light emitted from the arc tube 73 toward the focus.

In the light source lamp 21a, the arc tube 73 is formed of a light-transmitting quartz glass tube having a central portion swelled in a spherical shape, and a main body portion 73a at the center and first and first portions extending above and below the main body portion 73a. 2 fixing parts 73b and 73c. A spherical internal space is formed in the main body portion 73a, and in this internal space, mercury, rare gas, halogen, etc. are used in order to realize desired light emission characteristics corresponding to the light emission type of the arc tube 73. Contains gas. From the upper and lower ends of the main body portion 73a, that is, from the fixed portions 73b and 73c side, the tip portions of the pair of tungsten electrodes 81 and 81 extend to the center of the internal space of the main body portion 73a in a state of facing each other. Lead wires 85 are connected to the bases of both electrodes 81, 81 via metal foils 83 embedded in both fixing portions 73b, 73c, respectively. When a power source is connected to both lead wires 85, 85, both electrodes Arc discharge occurs between the tip portions of 81 and 81, the center of the main body portion 73a emits light with high brightness, and the light source light flux is emitted to the surroundings. Here, the voltage applied to both electrodes 81, 81 is
Although alternating current can be used, for example, lighting by direct current driving with the upper electrode 81 being positive is desirable. This is because a stable light emitting point can be formed between the electrodes 81, 81, and the heat flow of the main body portion 73a can be stabilized to prevent the arc tube 73 from being damaged.

As shown in the figure, when the arc tube 73 extends in the vertical direction, it is possible to prevent a cloudy portion or a blackened portion from being formed on the peripheral side surface of the main body portion 73a. This is because, when discharge light emission occurs in the main body portion 73a, the upper portion of the main body portion 73a on the first fixing portion 73b side does not reach the surrounding side surface even if it becomes relatively hot and clouded. ing. Further, even if the lower portion of the main body portion 73a on the second fixing portion 73c side is relatively lowered in temperature and blackened by precipitation of tungsten, it does not reach the peripheral side surface. As a result, it is possible to extend the life of the arc tube 73 and to generate high-luminance light source light over a long period of time.

The upper half of the main body portion 73 a of the arc tube 73 is covered by the main reflector 75 in a relatively large separated state, and the lower half of the main body portion 73 a is compared by the sub-reflector 77. Covered in a touched state.

Of these, the upper main reflecting mirror 75 includes a neck portion 75a through which the first fixing portion 73b of the arc tube 73 is inserted, and an elliptically curved main reflecting portion 75b extending from the neck portion 75a. It is an integral molded product made of glass. The neck portion 75a allows the main reflection portion 75b to be inserted into the main body portion 73a by inserting the first fixing portion 73b and filling the gap with the first fixing portion 73b with the fixing material MB that is an inorganic adhesive. It can be fixed in the aligned state. Also,
The inner glass surface of the main reflecting portion 75b is processed into an elliptical curved surface, and a reflecting surface 75r is formed on the surface.

As shown in FIG. 4B, the fixing portion 87 made of the fixing material MB for fixing the arc tube 73.
Has four through holes 87a extending linearly in the vertical direction, and these through holes 87a
Functions as a ventilation part that forms an air flow path between the lower surface (reflective surface 75r) and the upper surface above the main reflective portion 75b. Thereby, the heat accumulated in the upper part of the main reflecting portion 75b can be exhausted, for example, as convection above the main reflecting mirror 75, and heating of the main reflecting mirror 75 and the arc tube 73 can be prevented.

The lower sub-reflecting mirror 77 supports the sub-reflecting portion 77a that returns the light beam radiated downward from the main body portion 73a of the arc tube 73 to the main body portion 73a, and the second sub-reflecting mirror 77a while supporting the base portion of the sub-reflecting portion 77a.
And a support portion 77b fixed around the fixing portion 73c. Here, the inner glass surface of the sub-reflecting portion 77a is processed into a substantially spherical concave surface following the surface of the main body portion 73a, and a reflecting surface 77r is formed on the surface. In addition, the support portion 77b allows the second fixing portion 73c to be inserted into the center, and the sub-reflecting portion 77a is made to be the main body portion 73a by filling the gap with the second fixing portion 73c with the fixing material MB that is an inorganic adhesive. Can be fixed in an aligned state.

In the light source lamp 21a described above, the arc tube 73 is disposed along the system optical axis OA corresponding to the optical axis of the main reflection portion 75b, and the light emission center between the electrodes 81 and 81 in the main body portion 73a is mainly reflected. It arrange | positions so that it may become the 1st focus position of the elliptical curved surface of the part 75b. Arc tube 73
Is turned on, the light beam emitted from the main body portion 73a is reflected by the main reflecting portion 75b or reflected by the main reflecting portion 75b via the sub-reflecting portion 77a, and below the second fixed portion 73c, the system light. The light beam converges toward the second focal position on the axis OA.

2 and 3, the collimating lens 21b of the light source device 21 is disposed directly below the light source lamp 21a. The collimating lens 21b is a concave flat lens in which the entrance surface SA1 is concave and the exit surface SA2 is flat. The collimating lens 21b collimates the light source light emitted downward from the light source lamp 21a. Have The reflecting member 21c is a triangular prism whose cross section along the XZ plane is a right-angled isosceles triangle. The reflecting member 21c has a role of guiding the light source light collimated through the collimating lens 21b in the horizontal direction by bending the light source light in a direction orthogonal thereto. Thereby, the light beam from the light source device 21 can be taken out of the light source device 21 with a directivity that allows easy use. Here, the exit surface SA2 of the collimating lens 21b is supported by an incident surface which is one side surface SA3 orthogonal to the reflecting member 21c, and the collimating lens 21b and the reflecting member 21c are between the both surfaces SA2 and SA3. They are joined to each other by sandwiching an adhesive therebetween. Further, the inclined surface SA4 of the reflecting member 21c is a total reflection surface, and the other side surface SA5 orthogonal to the reflecting member 21c is provided with an antireflection coating for preventing returning light. In addition,
By manufacturing the reflecting member 21c with a prism instead of a simple mirror, the optical path length can be increased in a small space.

A pair of lens arrays 21d, 21e is opposed to the exit side surface SA5 of the reflecting member 21c.
A homogenizing optical system is arranged. These lens arrays 21d and 21e are composed of a plurality of element lenses arranged in a matrix, and these element lenses divide the light source light from the light source lamp 21a that has passed through the concave lens 21b and the reflecting member 21c and separately collect the light.・ Disperse. The polarization conversion member 21g converts the light source light emitted from the lens array 21e into, for example, only the S-polarized component perpendicular to the paper surface of FIG. Superimposing lens 21i
Allows the illumination light having passed through the polarization conversion member 21g to be appropriately converged as a whole, thereby enabling superimposing illumination on the light modulation devices of the respective colors provided in the light modulation unit 25. That is, the illumination light that has passed through both the lens arrays 21d and 21e and the superimposing lens 21i is a color separation optical system 23 described in detail below.
Then, the liquid crystal panels 25a, 25b, and 25c of the respective colors provided in the light modulator 25 are uniformly superimposed and illuminated.

In the light source device 21 described above, the main reflecting mirror 75 is the collimating lens 2 shown in FIG.
It fixes in the state aligned in the holder which has air permeability with 1b and the reflection member 21c. Also, the lens arrays 21d and 21e, the polarization conversion member 21g, and the superimposing lens 21
i is also fixed in a light-shielded light guide path, and a holder for holding the main reflecting mirror 75 and the like can be connected to the light guide path.

The color separation optical system 23 includes first and second dichroic mirrors 23a and 23b, three field lenses 23f, 23g, and 23h that are correction optical systems, and mirrors 23m, 23n, and 2;
3o, and constitutes an illumination device together with the light source device 21. Here, the first dichroic mirror 23a transmits, for example, red light (R light) and reflects green light (G light) and blue light (B light) among the three colors of red, green, and blue. Further, the second dichroic mirror 23b reflects, for example, green light and transmits blue light out of the incident two colors of green and blue. In the color separation optical system 23, the substantially white light source light from the light source device 21 first enters the first dichroic mirror 23a.
The red light that has passed through the first dichroic mirror 23a remains, for example, S-polarized light, and the mirror 23m
Then, the light enters the field lens 23f. Further, the green light reflected by the first dichroic mirror 23a and further reflected by the second dichroic mirror 23b is incident on the field lens 23g as S-polarized light, for example. Further, the blue light transmitted through the second dichroic mirror 23b is, for example, S-polarized light, and enters the field lens 23h for adjusting the incident angle via the lenses LL1 and LL2 and the mirrors 23n and 23o. Lens LL1, LL
2 and the field lens 23h constitute a relay optical system. This relay optical system
The image of the first lens LL1 is almost directly converted into the field lens 23 via the second lens LL2.
The function to transmit to h is provided.

The light modulation unit 25 includes three liquid crystal panels 25a to 25c and three sets of polarizing filters 25e, 25f, and 25g arranged so as to sandwich the liquid crystal panels 25a to 25c. here,
The liquid crystal panel 25a for red light and the pair of polarizing filters 25e and 25e sandwiching the liquid crystal panel 25a for red light are liquid crystal light valves for red that are used for two-dimensionally modulating the luminance of red light based on image information. Constitute. Similarly, the liquid crystal panel 25b for green light and the corresponding polarizing filter 25f,
25f also constitutes a liquid crystal light valve for green, and the liquid crystal panel 25c for blue light and the polarizing filters 25g and 25g also constitute a liquid crystal light valve for blue.

Red light branched by passing through the first dichroic mirror 23a of the color separation optical system 23 enters the first liquid crystal panel 25a for red light in the first optical path OP1 through the field lens 23f. The green light branched by being reflected by the second dichroic mirror 23b of the color separation optical system 23 enters the second liquid crystal panel 25b for green light in the second optical path OP2 through the field lens 23g. The third for blue light in the third optical path OP3
The blue light branched by passing through the second dichroic mirror 23b is incident on the liquid crystal panel 25c via the field lens 23h. The three color lights respectively incident on the liquid crystal panels 25a to 25c are modulated in accordance with drive signals or image signals input as electric signals to the liquid crystal panels 25a to 25c. At that time, polarizing filters 25e, 25f,
25g adjusts the polarization direction of the illumination light incident on the liquid crystal panels 25a, 25b, and 25c, and component light in a predetermined polarization direction from the modulated light emitted from the liquid crystal panels 25a, 25b, and 25c is image light. As taken out. That is, the red liquid crystal light valve 25
a, 25e, green liquid crystal light valves 25b, 25f, and blue liquid crystal light valves 25c, 25e each function as a non-light-emitting light modulation device that modulates the spatial intensity distribution of incident illumination light. is doing.

The cross dichroic prism 27 is a composite optical system, has a substantially square shape in plan view in which four right angle prisms are bonded together, and a pair of dielectric multilayers that intersect in an X shape at the interface where the right angle prisms are bonded together. Films 27a and 27b are formed. One first dielectric multilayer film 27a reflects red light, and the other second dielectric multilayer film 27b reflects blue light. The cross dichroic prism 27 transmits red light from the liquid crystal panel 25a to the first dielectric multilayer film 27.
The green light from the liquid crystal panel 25b goes straight through and through the first and second dielectric multilayer films 27a and 27b and is emitted from the liquid crystal panel 25c to the second dielectric. Reflected by the body multilayer film 27b and emitted to the right in the traveling direction.

The projection lens 29 converts the color image light synthesized by the cross dichroic prism 27 into
The light is emitted in the direction of the horizontal system optical axis OA. This color image light is reflected from the reflecting mirror 1 shown in FIG.
6 is projected onto the rear surface of the transmission screen 18 at a desired magnification. That is, a color moving image or a color still image having a desired magnification corresponding to the drive signal or image signal input to each of the liquid crystal panels 25 a to 25 c is projected from behind onto the transmissive screen 18.

As is clear from the above description, according to the rear projection device 100 according to the present embodiment, the light source 21 emits the light beam emitted from the sub-reflecting mirror 77 to the opposite side of the main reflecting mirror 75 in the main body of the arc tube 73. Since it returns to the light emission part of the part 73a, the utilization efficiency of a light beam can be improved. Furthermore, in this embodiment, since the 1st fixing | fixed part 73b which supports the main reflective mirror 75 is arrange | positioned at the upper side of a perpendicular direction, it becomes difficult to form a cloudy part and a blackening part in the surrounding side surface of the main-body part 73a.

[Second Embodiment]
Hereinafter, the rear projection apparatus according to the second embodiment will be described. The rear projection apparatus according to the present embodiment is a modification of the rear projection apparatus 100 according to the first embodiment shown in FIG. 1 and the like, and parts not specifically described are the same as those of the apparatus according to the first embodiment. .

FIG. 5 shows a light source device 121 incorporated in a rear projection device according to the second embodiment.
FIG. In this case, an air-cooling type cooling device 122 is disposed below the reflecting member 21c, and the arc tube 73 and the main reflecting portion 75b can be forcibly cooled from below. At this time, the reflecting member 21c and the collimating lens 21b can be cooled together and the reflecting member 21c.
Or the like can be used as a shield to prevent the cooling air from directly hitting the arc tube 73 or the main reflecting portion 75b, and stable operation of the arc tube 73 can be ensured, and the life of the arc tube 73 can be extended. Can do. The main body portion 73a of the arc tube 73 is covered with a sub-reflecting mirror 77, and is strong against cooling air from below. That is, even if the arc tube 73 is forcibly cooled from below, the sub-reflecting mirror 77 reliably shields the cooling air, so that the lower portion of the main body portion 73a can be prevented from being excessively cooled and blackened.

In the present embodiment, the through-hole 87a formed in the upper part of the main reflecting portion 75b can only be used to raise the heated air, but the upper part of the through-hole 87a is set to a negative pressure. The heated air can be forcibly sucked upward.

[Third Embodiment]
Hereinafter, a rear projection apparatus according to the third embodiment will be described. The rear projection apparatus according to the present embodiment is a modification of the rear projection apparatus 100 according to the first embodiment shown in FIG. 1 and the like, and parts not specifically described are the same as those of the apparatus according to the first embodiment. .

FIG. 6 is a diagram for explaining a projector main body 210 incorporated in the rear projection apparatus according to the third embodiment. As for the light source device 21, the light source device 21 described in FIG.
However, the color separation optical system 223 uses a color wheel 32a, and the light modulation unit 225 uses a digital micromirror device 225. The projection lens 229 for forming the projection image of the digital micromirror device 225 is the same as the projection lens 29 described with reference to FIG. The color separation optical system 223 includes an incident lens 31 for adjusting the beam size, a color wheel 32a for separating incident light source light into each time-series color light, a rod integrator 33 for equalizing each color light, And an exit lens 34 that makes the illumination light after the uniformization into a necessary beam shape and enters the digital micromirror device 225. Here, color wheel 3
2a can be rotated by a motor 32b, and a circular filter of three colors of red, green and blue is divided into three equal parts on the filter surface FL of the color wheel 32a.

The illumination light emitted from the light source device 21 enters the color wheel 32a. The color wheel 32a converts the illumination light made into a spot shape by the incident lens 31 into red, green, and blue.
The color is ejected after color separation in time series. The rod integrator 33 provided in the subsequent stage of the color wheel 32a equalizes each color light separated in time series by dividing and superposing the wavefront. The exit lens 34 provided at the rear stage of the rod integrator 33 forms an image of the exit end of the rod integrator 33 on the digital micromirror device 225, and uniform illumination of the digital micromirror device 225 is achieved. The digital micromirror device 225 reflects the illumination light incident thereon in synchronization with the incidence of each color illumination light from the color wheel 32a by the micromirror corresponding to each pixel according to the input image signal. The image light emitted from the digital micromirror device 225 is emitted from the projection lens 29.
Is projected onto the screen 18 (see FIG. 1).

[Fourth Embodiment]
Hereinafter, the rear projection apparatus according to the fourth embodiment will be described. The rear projection apparatus of the present embodiment is a modification of the projector main body 210 of the rear projection apparatus according to the third embodiment shown in FIG. 6 and the like, and parts not specifically described are the same as those of the apparatus of the first embodiment. Shall.

FIG. 7 is a diagram illustrating a projector main body 310 incorporated in the rear projection apparatus according to the fourth embodiment. In this case, in the light source device 321, a plane mirror 321c is provided below the light source lamp 21a in place of the parallelizing lens 21b and the reflecting member 21c (see FIG. 6).
Is arranged. As a result, since condensing becomes unnecessary, the incident lens 31 is omitted in the color separation optical system 323.

[Fifth Embodiment]
Hereinafter, a rear projection apparatus according to a fifth embodiment will be described. The rear projection apparatus of the present embodiment is a modification of the projector main body 210 of the rear projection apparatus according to the third embodiment shown in FIG. 6 and the like, and parts not specifically described are the same as those of the apparatus of the first embodiment. Shall.

FIG. 8 is a diagram illustrating a projector main body 410 incorporated in the rear projection apparatus according to the fifth embodiment. In this case, in the light source device 421, the collimating lens 21b
Instead of the reflecting member 21c (see FIG. 6), a small prism 421c is disposed in the vicinity of the second focal position of the light source lamp 21a, and the light source light traveling vertically downward is bent in the horizontal direction. In the color separation optical system 423, the color wheel 3 is disposed on the exit end side of the rod integrator 33.
2a is arranged. In this case, the illumination light that has been made uniform by the rod integrator 33 is separated into time-series color lights by the color wheel 32a.

Although the present invention has been described based on the above embodiments, the present invention is not limited to the above embodiments, and can be implemented in various modes without departing from the gist thereof. Such modifications are also possible.

In the light source lamp 21a of the above embodiment, the reflecting surface 75 of the main reflecting mirror 75 or the sub reflecting mirror 77.
r and 77r are not limited to elliptical curved surfaces and spherical surfaces, but can be various curved surfaces according to the accuracy and other specifications required for the light source lamp 21a.

Further, in the projector 10 of the above embodiment, the two lens arrays 21d and 21e and the rod integrator 33 are used to divide the light from the light source lamp 21a and the like into a plurality of partial light beams.
However, the present invention is also applicable to a projector that does not use such lens arrays 21d, 21e.

In the first embodiment and the second embodiment, the PBS array that uses the light from the light source lamp 21a and the like as polarized light in a specific direction is used. However, the present invention is applicable to a projector that does not use such a PBS array. Applicable.

In the first and second embodiments, the example of the projector 10 using three light modulation devices has been described. However, the present invention uses one, two, or four or more light modulation devices. It can also be applied to a projector.

In the first embodiment and the second embodiment, an example in which the present invention is applied to a transmissive projector has been described. However, the present invention can also be applied to a reflective projector. Here, “transmission type” means that the light valve including the liquid crystal panel is a type that transmits light, and “reflection type” is a type that the light valve reflects light. Means. In the case of a reflection type projector, the light valve can be constituted only by a liquid crystal panel, and a pair of polarizing plates is unnecessary.

It is a side view explaining the rear projection device concerning a 1st embodiment. It is a top view explaining the structure of the optical system of the projector main body shown in FIG. It is a side view explaining the structure of the optical system of the projector main body shown in FIG. (A) is side sectional drawing of a light source lamp, (b) is a partial top view of a light source lamp. It is a side view explaining the light source device of the projector main body which concerns on 2nd Embodiment. It is a side view explaining the projector main body which concerns on 3rd Embodiment. It is a side view explaining the projector main body which concerns on 4th Embodiment. It is a side view explaining the projector main body which concerns on 5th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Projector body, 16 ... Reflection mirror, 18 ... Screen, 18 ... Transmission type screen, 21 ... Light source device, 21a ... Light source lamp, 21b ... Concave lens, 21b
... Parallelizing lens, 21c ... Reflecting member, 21d, 21e ... Lens array, 21g ... Polarization converting member, 21i ... Superimposing lens, 23 ... Color separation optical system, 23a, 23b ... Dichroic mirror, 25 ... Light modulator, 25a, 25b, 25c ... Liquid crystal panel, 25e
, 25f, 25g ... polarizing filter, 27 ... cross dichroic prism, 29 ... projection lens, 32a ... color wheel, 33 ... rod integrator, 73 ... arc tube, 73a ... main body part, 73b ... first fixed part, 73c ... second Fixing part, 75 ... main reflecting mirror, 75b ... main reflecting part, 77 ... sub reflecting mirror, 77a ... sub reflecting part, 81, 81 ... electrode, 87 ... fixing part, 87a ... through hole, 100 ... rear projection device, 122
... cooling device, OA ... system optical axis

Claims (9)

A main body portion that houses a pair of electrode ends for discharge; a first fixing portion that houses a conductive member that extends vertically upward from the main body portion and extends from one electrode end; and the other that extends vertically downward from the main body portion An arc tube having a second fixing portion for accommodating a conductive member extending from the electrode end of
A main reflecting mirror that is provided on the first fixed portion side of the arc tube and emits a luminous flux emitted from the arc tube in a predetermined direction;
A sub-reflector that is provided on the second fixed portion side of the arc tube and returns a light beam emitted from the arc tube to the opposite side of the main reflector to the light emitter in the main body portion of the arc tube;
A projector comprising, as a light source device, a reflecting member that guides a light beam reflected by the main reflecting mirror in a horizontal direction by bending the light beam in an orthogonal direction. The projector according to claim 1, wherein the light source device further includes a collimating lens that collimates the light beam reflected by the main reflecting mirror and guides the light beam to the reflecting member. The reflecting member is a prism, and the exit surface of the collimating lens is flat; and
The projector according to claim 2, wherein the projector is bonded to an incident surface of the prism. The ventilation part which is provided around the said 1st fixing | fixed part and forms the flow path of air between the lower surface and upper surface in the upper part of the said main reflective mirror is provided. Projector. The projector according to claim 4, wherein the first fixing portion is fixed to an upper portion of the main reflecting mirror through a fixing material, and the ventilation portion is a through hole formed in the fixing material. The projector according to any one of claims 1 to 5, further comprising an air cooling device that supplies a cooling airflow from vertically below toward the arc tube, the main reflecting mirror, and the sub-reflecting mirror. The projector according to any one of claims 1 to 6, wherein the main reflecting mirror has an elliptical reflecting surface. A light modulating unit that modulates a light beam emitted from the light source device according to input image information and forms modulated light;
A projection optical system that projects the modulated light from the light modulator as image light;
The projector according to any one of claims 1 to 7, further comprising: The light modulation unit includes a light modulation device for each color that modulates each color light,
A color separation optical system that separates a light beam emitted from the light source device into light of each color and guides the light to a light modulation device for each color, and color synthesis that combines the modulated light of each color modulated by the light modulation device for each color An optical system,
The projector according to claim 8, wherein the projection optical system projects the image light combined by the color combining optical system.

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