JP2000258842A - Projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device constituted so that a filter cover fitted to the air intake port of a housing case can be easily attached and detached even when the projection type display devices are stacked and arranged. SOLUTION: The air intake port 240 of the housing case 2 is provided with the filter cover 241 which can be detached along the forming surface of the port 240. Due to that, the cover 241 need not be detached in the outer surface direction of the forming surface of the port 240. Thus, even when the projection type display devices 1 are stacked and arranged and the air intake port of one projection type display device is opposed to the other adjacent projection type display device, the cover 241 is easily detached and attached.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electro-optical device for forming an optical image according to image information, a projection lens for enlarging and projecting an image formed by the electro-optical device, and a main body including the electro-optical device. The present invention relates to a projection display device having an outer case to cover.

[0002]

BACKGROUND ART Conventionally, a light source unit having a light source,
An electro-optical device that forms an optical image of a light beam emitted from the light source in accordance with image information, a projection lens that enlarges and projects an image formed by the electro-optical device, and a lens position adjustment that adjusts a projection position of the image 2. Description of the Related Art There is known a projection display device including a mechanism and an outer case for housing these components.

[0003] Such a projection display device is widely used for multimedia presentations at conferences, conferences, exhibitions and the like.

Incidentally, since the heat generating members such as the light source and the power supply unit are housed in the outer case of the projection display device, it is necessary to efficiently cool the inside of the device.

[0005] For this reason, in the projection type display device, an air intake for taking in cooling air from outside is formed in an outer case for housing the components. Normally, an air filter is provided at the air inlet to prevent dust and dirt from entering the inside of the apparatus. Such a filter cover is used to prevent clogging of the air filter, etc.
It is necessary to remove it regularly for cleaning and replacement. Therefore, in a conventional projection display device, a filter cover to which an air filter is attached is provided so that the filter cover can be attached to and detached from the outer surface of the bottom surface of the outer case.

[0006]

By the way, a plurality of projection type display devices are juxtaposed (stacked), and the images projected from the respective projection type display devices are superimposed on a projection surface such as a screen to project a projected image. Is being clarified.

However, in such a stack arrangement, if the air inlet faces another adjacent projection type display device, the conventional filter cover attaching / detaching structure removes the cover from an out-of-plane direction. Since the filter cover must be attached and detached, the filter cover cannot be attached and detached while the filter is arranged in a stack. Therefore, every time the air filter is cleaned or replaced, it is necessary to lift the device once and turn it sideways, and also, after cleaning or replacing the air filter, it is necessary to adjust the image projection position again, which is troublesome. Is a problem.

It is an object of the present invention to provide a projection type display device in which a filter cover can be easily attached and detached even when the projection type display devices are arranged in a stack.

[0009]

A projection display apparatus according to the present invention comprises an electro-optical device for forming an optical image according to image information, and a projection lens for enlarging and projecting an image formed by the electro-optical device. A projection-type display device comprising: an outer case that covers a main body including an electro-optical device, wherein a surface of the outer case has an air inlet through which external air is introduced into the outer case; A filter cover provided with an air filter covering the inlet, wherein the filter cover is detachable along a surface of the outer case in which the air inlet is formed. .

According to the present invention, since the filter cover can be attached and detached along the surface of the outer case, the attachment and detachment of the filter cover can be performed even when the filter cover is arranged in a stack. Therefore, every time the air filter is cleaned or replaced, there is no need to lift the device once and turn it sideways, or to adjust the image projection position again after cleaning or replacing the air filter.

In the above-mentioned projection display device, it is desirable that the air intake is formed on the bottom surface of the outer case.

With this configuration, when the filter cover is removed, dust adhering to the air filter and the filter cover does not enter the inside of the apparatus.

In the case where one of the outer case and the filter cover is formed with a guide rail extending in a direction in which the filter cover is attached and detached, and the other is formed with a guide groove formed in the filter cover to engage with the guide rail, Engagement of the case and the filter cover is ensured, and attachment / detachment is further facilitated.

In this case, one of the outer case and the filter cover is provided with an engaging projection, and the other is formed with a concave portion engaging with the engaging projection. When the movement of the cover in the mounting / removing direction is prevented, the filter cover does not slide off even if slight vibration or tilt occurs during transportation or handling, preventing dust from entering the inside of the device. be able to.

Further, it is preferable that the filter cover is provided with a suppressing portion for preventing the air filter from protruding out of the plane.

With this configuration, the air filter does not fly out of the plane of the filter cover, so that there is no problem in sliding the filter cover, and as a result, the filter cover can be easily removed.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

(1) Overall Configuration of the Apparatus FIGS. 1 and 2 are schematic perspective views of a projection display apparatus 1 according to the present embodiment. FIG. 1 is a perspective view as viewed from above, and FIG. It is the perspective view seen from the lower surface side.

The projection display apparatus 1 separates a light beam emitted from a light source lamp as a light source into three primary colors of red (R), green (G), and blue (B), and separates the light beams of these colors into an electro-optical device. Modulation is performed through a liquid crystal panel according to image information in accordance with image information, and modulated light fluxes of the respective colors are combined by a prism (color combining optical system) and enlarged and displayed on a projection surface via a projection lens 6. Things. Projection lens 6
Except for a part, each component is housed inside the outer case 2.

(2) Structure of the Outer Case The outer case 2 is basically composed of an upper case 3 covering the upper surface of the device, a lower case 4 constituting the bottom surface of the device, a front case 9 covering the front portion, and a back portion. And a rear case 5 (FIG. 2) that covers the rear case 5. The rear case 5 is made of a metal such as magnesium except that the rear case 5 is made of a resin.

As shown in FIG. 1, the upper case 3
A number of communication holes 25R and 25L for loudspeakers are formed at the left and right ends on the front side of the upper surface of the. An operation panel 60 for adjusting the image quality and the like of the projection display 1 is provided between the communication holes 25R and 25L. Further, a light receiving unit 70 for receiving an optical signal from a remote controller (not shown) is provided in an upper right portion of the front case 9.

As shown in FIG. 2, an air inlet 240 for taking in cooling air for cooling the inside of the apparatus is provided substantially at the center of the bottom surface of the lower case 4. The air inlet 240 is provided with an air filter, which will be described in detail later. By attaching and detaching the filter cover 241 from the side of the lower case 4, the air filter attached to the filter cover 241 is cleaned or replaced. It is possible to do.

Further, on the bottom surface of the lower case 4, feet 31R and 31L are provided at left and right corners at the front end thereof, and a foot 31C is provided at a substantially central portion at the rear end. Note that the inclination of the display screen can be changed by adjusting the vertical movement of the feet 31R and 31L.

The rear case 5 is, as shown in FIG.
An interface panel 501 provided corresponding to various input / output terminal groups 51 arranged on the rear side of the apparatus;
Exhaust port 160 as a vent for discharging air inside the device
Lamp replacement lid 502 provided with light receiving unit 70
It is composed of An AC inlet 50 for supplying external power is arranged on the back side of the apparatus.

A hole 11 is formed on a side surface of the outer case 2 at a connection portion between the upper case 3 and the lower case 4. The hole 11 is provided in a pop-up type The end surface of the rotary knob 20 is exposed. The end surface of the rotary knob 20 and the surface of the outer case 2 are substantially flush.

(3) Internal Structure of the Device FIG. 3 shows the internal structure of the projection display device 1.

As shown in FIG. 1, a power supply unit 7 as a power supply disposed on one side of the projection lens 6 and a light source as a light source unit disposed behind the power supply unit 7 are provided inside the apparatus 1. The lamp unit 8, the optical unit 10 constituting the optical system, a driver board (not shown) for driving the electro-optical device 925 in the unit 10, a main board (not shown) for controlling the entire device 1, and the like are accommodated therein. ing.

The power supply unit 7 transforms the electric power from the AC inlet 50, and changes the power from the light source lamp unit 8, a driver board, a main board, and an intake fan (not shown) disposed below or above and below the electro-optical device 925. ),
And a power supply circuit board provided with a power supply filter, a transformer (transformer), a rectifier circuit, a smoothing circuit, a voltage stabilizing circuit, and the like. And a lamp driving board for driving the light source lamp 181 of the light source lamp unit 8.

The light source lamp unit 8 constitutes a light source portion of the projection display device 1. As shown in FIG. 4, the light source device 183 includes a light source lamp 181 and a reflector 182, and the light source device 183. And a lamp housing (not shown) for housing the lamp housing. Such a light source lamp unit 8 is cooled by cooling air from the above-described intake fan or cooling air sucked from a gap 92 (FIG. 6) between the outer case 2 and the projection lens 6. First, immediately after being sucked, the electro-optical device 925 and the power supply unit 7 and the like are cooled, and thereafter, the air flows backward so as to cool substantially the entire area of the inside of the device 1. 8, the air is exhausted by the exhaust fan 16 at the rear. Therefore, the exhaust fan 16
The light source lamp unit 8 is arranged immediately before the above, so that the light source device 183 inside the light source lamp unit 8 can be efficiently cooled by a large amount of cooling air.

The optical unit 10 is a unit for optically processing a light beam emitted from the light source lamp unit 8 to form an optical image corresponding to image information, and includes an illumination optical system 923, a color separation optical system 924, It is configured to include an electro-optical device 925 and a prism unit 910 as a color combining optical system. Optical elements of the optical unit 10 other than the electro-optical device 925 and the prism unit 910 include:
It is configured to be held vertically by being sandwiched between upper and lower light guides (not shown). The upper light guide and the lower light guide are integrated into a lower case 4.
Side is fixed by a fixing screw. These light guides are also fixed to the prism unit 910 side by fixing screws.

As shown in FIG. 5, the prism unit 910 having a rectangular parallelepiped shape is fixed to the back surface side of a substantially L-shaped side of the head body 903 formed of an integrally molded product of magnesium by a fixing screw. Also, the electro-optical device 925
Liquid crystal panels 925R, 925G, 925B constituting
Are fixed to three side surfaces of the prism unit 910 via fixing members.

The driver board includes an electro-optical device 925.
Drive each liquid crystal panel 925R, 925G, 925B
It is for controlling and is arranged above the optical unit 10.

The main board is provided with a control circuit for controlling the whole of the projection display device 1, and is arranged above the driver board. Such a main board is electrically connected to the driver board and the operation panel 60 described above.

(4) Structure of Optical System Next, the optical system of the projection display device 1, that is, the optical unit 10
Will be described with reference to the schematic diagram shown in FIG.

As described above, the optical unit 10 includes the illumination optical system 923 for equalizing the in-plane illuminance distribution of the light beam (W) from the light source lamp unit 8, and the illumination optical system 923.
A color separation optical system 924 that separates a light beam (W) from light into red (R), green (G), and blue (B), and an electro-optical device that modulates each of the light beams R, G, and B according to image information. 925, and a prism unit 910 as a color synthesizing optical system for synthesizing each color light beam after modulation.

The illumination optical system 923 includes the first lens plate 92
1 and a second lens plate 922 disposed on the emission side thereof
And a reflection mirror 931 that bends the optical axis 1a of the light beam W emitted from the light source lamp unit 8 toward the front of the device 1.

The first lens plate 921 has a plurality of rectangular lenses arranged in a matrix. The first lens plate 921 divides a light beam emitted from a light source into a plurality of partial light beams, and separates each of the partial light beams into a second lens. Light is collected near the plate 922.

The second lens plate 922 has a plurality of rectangular lenses arranged in a matrix, and converts each partial light beam emitted from the first lens plate 921 into a liquid crystal constituting the electro-optical device 925. Panels 925R, 925G, 92
5B (described later).

As described above, in the projection type display apparatus 1 of this embodiment, the liquid crystal panels 925R and 925R are controlled by the illumination optical system 923.
25G and 925B can be illuminated with light having substantially uniform illuminance, so that a projection image without illuminance unevenness can be obtained.

The color separation optical system 924 includes a blue-green reflecting dichroic mirror 941 and a green reflecting dichroic mirror 9.
42 and a reflection mirror 943. First, in the blue-green reflecting dichroic mirror 941, the blue light beam B included in the light beam W emitted from the illumination optical system 923 is used.
The green light flux G is reflected at a right angle, and travels toward the green reflection dichroic mirror 942.

The red light beam R passes through the blue-green reflecting dichroic mirror 941, is reflected at a right angle by the rear reflecting mirror 943, and is emitted from the emission unit 944 of the red light beam R to the prism unit 910 side.

Next, the blue-green reflecting dichroic mirror 94
Of the blue and green light fluxes B and G reflected by 1, only the green light flux G is reflected at a right angle by the green reflection dichroic mirror 942 and emitted from the emission unit 945 of the green light flux G to the prism unit 910 side.

The blue light beam B having passed through the green reflecting dichroic mirror 942 is emitted from the emission section 946 of the blue light beam B to the relay optical system 927 side. In this example, the color separation optical system 92 is output from the emission portion of the light beam W of the illumination optical system 923.
4, the emission portions 944, 94 of the respective color light beams R, G, B.
The distances to 5,946 are all set to be substantially equal.

The red and green luminous flux R of the color separation optical system 924
Condensing lenses 951 and 952 are arranged on the emission sides of the G emission sections 944 and 945, respectively. Therefore, the red and green light fluxes R and G emitted from the respective emission portions are incident on these condenser lenses 951 and 952 and are parallelized.

The red and green luminous fluxes R and G thus collimated pass through the incident-side polarizing plates 960R and 960G and enter the liquid crystal panels 925R and 925G, which are light modulation devices, and are modulated to correspond to each color light. The added image information is added.
That is, these liquid crystal panels 925R and 925G
The switching control is performed by the above-mentioned driver board in accordance with the image information, whereby each color light passing therethrough is modulated.

On the other hand, the blue light beam B is transmitted to the relay optical system 927
, And is guided to the corresponding liquid crystal panel 925B, where it is similarly modulated according to image information. still,
Liquid crystal panels 925R, 925G, 925B of the present embodiment
For example, a device using a polysilicon TFT as a switching element can be adopted.

The relay optical system 927 includes a condenser lens 954 disposed on the exit side of the exit portion 946 of the blue light beam B, an entrance side reflection mirror 971, an exit side reflection mirror 972, and an arrangement between these reflection mirrors. Intermediate lens 973
Condensing lens 95 arranged on the front side of liquid crystal panel 925B
The blue light flux B emitted from the condenser lens 953 is incident on the liquid crystal panel 925B through the incident-side polarizing plate 960B and is modulated.

At this time, the optical axis 1a of the light beam W and the optical axes 1r, 1g, 1b of the respective color light beams R, G, B are formed on the same plane. The length of the optical path of each color light beam, that is, the distance from the light source lamp 181 to each liquid crystal panel, is the longest for the blue light beam B, and therefore, the loss of the light amount of this light beam is the largest. However, by interposing the relay optical system 927, the light amount loss can be suppressed.

Next, each of the liquid crystal panels 925R, 925G,
The color light beams R, G, and B modulated through 925B are incident on the prism unit 910 through the output-side polarizing plates 961R, 961G, and 961B, and are combined there. The color image synthesized by the prism unit 910 is enlarged and projected on a projection plane at a predetermined position via the projection lens 6.

(5) Mounting Structure of Projection Lens In FIG. 5, the projection lens 6 has a light incident side connected to a lens position adjusting mechanism, and is operated up and down by the lens position adjusting mechanism. Further, as shown in FIG. 1, the light emission side of the projection lens 6 protrudes outside from an opening 93 formed in the front case 9.

The opening 93 is formed in a long hole shape larger than the diameter of the projection lens 6 in consideration of the fact that the projection lens 6 moves up and down by the lens position adjusting mechanism 40. A cylindrical flange portion 90 is formed toward the inside of the device 1.

For this reason, a gap 92 is formed between the outer peripheral surface of the projection lens 6 and the periphery (flange portion 90) of the opening 93 of the front case 9, and this gap 92 is formed as shown in FIG.
As shown in FIG. 7, a dustproof and elastic ventilation member 91 attached to the flange portion 90 with a double-sided tape or the like.
It is closed by. Thus, cooling air for cooling the inside of the device 1 is sucked into the device 1 from the gap 92.

On the other hand, since the ventilation member 91 has elasticity, as shown in FIG.
The projection lens 6 can be moved upward by a lens position adjusting mechanism (not shown), and the projection lens 6 can be moved downward as shown in FIG. In addition, as the ventilation member 91, a mesh-shaped cloth or a metal net can be adopted in addition to a sponge having open cells. Also, the ventilation member 9
The color 1 is the same as the color of the outer case 2 so as to be inconspicuous from the outside.

(6) Filter cover and mounting / detaching structure of filter cover FIGS. 6 to 8 show details of the filter cover 241 and the mounting / detaching structure of the filter cover 241.

The filter cover 241 is connected to the air inlet 24.
0 is a thin plate-like member having a substantially rectangular shape and formed to have a size capable of covering 0. Also, the filter cover 241
Is detachable along the bottom surface of the outer case 2. At this time, the filter cover 241 is slid in the direction of the arrow S (detachment direction) and is attached and detached.

On the bottom surface of the outer case 2, a step portion 246 is formed to be lower by the thickness of the filter cover 241, and a square air inlet 240 is formed in a part of the step portion 246. Have been. Further, guide rails 244 are provided at both ends of the step portion 246 along the attachment / detachment direction of the filter cover 241 so as to project in directions facing each other. Further, a recess 245 extending in a direction intersecting with the attaching / detaching direction is provided on the side of the step portion 246 opposite to the air intake 240.

A plurality of slits 241A are formed in a part of the filter cover 241 so as to face the air inlet 240 and to take in air therefrom. On the back surface of the slit 241A (the top surface when the filter cover 241 is attached), a circular ring-shaped accommodation portion 241 is provided.
C is provided. By housing the air filter 242 that covers the air intake 240 in the housing portion 241C, the air filter 242 can be attached to the filter cover 241. The housing portion 241C is provided with a tongue-shaped holding portion 241D protruding inward from the ring-shaped portion along the surface of the air filter 242 in order to prevent the housed air filter 242 from protruding out of the plane. ing.
The height of the housing portion 241C is smaller than the thickness of the filter cover 241. Therefore, the air filter 242 does not jump out of the plane of the filter cover 241.

An L-shaped cross-section projection 241F is formed continuously on both sides of the filter cover 241 in the mounting / removing direction. One side of the projection 241F and the filter cover 241 in the mounting / removing direction. The two ends are parallel. The end of the one side is formed shorter than both ends of the cover 241, and the protrusion 241 </ b> F and both ends of the cover 241 form a guide groove 241. And
The guide groove 241 is engageable with the guide rail 244 of the outer case 2, so that the filter cover 241 can slide along the guide rail 244.

At a position opposite to the slit 241A in the filter cover 241, there is formed a rectangular handle portion 241B recessed from the front surface (the lower surface when the filter cover 241 is attached) to the back surface. The filter cover 241 can be pulled out by inserting a finger into the filter cover 241. Two slits 241E are formed at both ends of the handle portion 241B in the mounting / removing direction. Then, as shown in FIG.
On the back surface of B, an engagement protrusion 243 is provided across these slits 241E. This engagement projection 243
Are formed in a triangular cross section.

The engaging projection 243 and the outer case 2
Can be engaged with the concave portion 245 of the step portion 246. Therefore, when the filter cover 241 is pushed in while being slid, the two are engaged with each other, thereby positioning the filter cover 241 with respect to the outer case 2 and restricting the movement in the attaching / detaching direction.

(7) Effects of the Embodiment According to the above-described embodiment, the following effects can be obtained.

That is, in the projection display device 1, the filter cover 241 to which the air filter 242 is attached
Can be attached and detached by sliding along the bottom surface. That is, it is not necessary to remove the outer surface from the bottom surface. Therefore, when the projection type display devices 1 are arranged in a stack, even if the air intake 240 of one projection type display device 1 is opposed to another adjacent projection type display device 1, the projection type display device 1 is inserted and removed from the side. The filter cover 241 can be easily attached and detached.
Therefore, every time the air filter 242 is cleaned or replaced,
There is no need to lift the device once and turn it sideways, or to adjust the image projection position again after cleaning or replacing the air filter.

Since the air inlet 240 is formed on the bottom surface of the outer case 2, even if the filter cover 241 is removed, dust adhering to the filter cover 241 and the air filter 242 may fall downward. Also does not enter the inside of the outer case 2, that is, the inside of the device.

Further, the guide rail 24 is attached to the outer case 2.
4 are formed, and the guide rail 2 is attached to the filter cover 241.
Since the guide groove 241G to be engaged with 44 is formed, the engagement between the outer case 2 and the filter cover 241 is reliable, and the attachment and detachment are easy.

An engagement protrusion 243 is provided on the back surface of the filter cover 241, and the engagement protrusion 243 is provided on the outer case 2.
Is formed, so that when the filter cover 241 is slid and attached,
43 and 245 are engaged, the filter cover 241 is positioned, and the movement in the attaching / detaching direction is prevented.
Therefore, when carrying or handling, slight vibration,
Even when the filter cover 241 is tilted or the like, the filter cover 241 does not slide off and the dust can be prevented from entering the inside of the apparatus.

Further, since the ring-shaped receiving portion 241C of the filter cover 241 is provided with a tongue-shaped holding portion 241D for holding the air filter 242 housed therein, the air filter 242 is formed of the filter cover 241. It will not jump out of the plane. Therefore, the slide of the filter cover 241 is not hindered, and as a result, the attachment and detachment of the filter cover 241 become easy.

Further, the filter cover 241 is formed with a handle 241B recessed from the surface, and a finger of a hand can be inserted into the handle 241B, so that the filter cover 241 can be easily removed.

Further, since the engaging projections 243 provided on the back surface of the handle portion 241B of the filter cover 241 straddle the two slits 241E, the slits 241E act as springs. Therefore,
When the filter cover 241 is slid and attached, the engagement protrusion 243 is pushed toward the concave side of the handle portion 241B. When engaging with the concave portion 245 of the step portion 246, the engagement protrusion 243 is strongly pushed by the elastic return, and the engagement is more reliable.

(8) Modifications of the Embodiment The present invention is not limited to the above-described embodiments, but includes the following modifications.

For example, in the above-described embodiment, the filter cover 241 and the outer case 2 are engaged with each other by forming the guide rail 244 on the outer case 2 and forming the guide groove 241G on the filter cover 241. However, the guide grooves are formed in the outer case 2 in reverse.
Guide rails may be respectively formed on the filter cover 241 and both may be engaged. Even in this case, the same effect as described above can be obtained.

In the above-described embodiment, the positioning between the filter cover 241 and the outer case 2 is determined by the engagement projection 24 provided on the back surface of the handle 241B of the filter cover 241.
3 is provided in a concave portion 245 provided in a step portion 246 of the outer case 2.
, But the recess is formed in the filter cover 24.
1 and the engaging protrusion may be provided on the outer case 2 side. The filter cover 241 and the outer case 2
Positioning with is not limited to such a configuration, for example,
A protrusion having a predetermined width may be provided at the tip of the filter cover 241 in the mounting / removing direction, while the exterior case 2 may be provided with a locking member formed of, for example, a spring material and sandwiching the protrusion.

Further, in the above embodiment, the outer case 2
The concave portion 245 provided in the step portion 246 has a shape that is continuous over the width direction of the step portion 246. However, since the concave portion only needs to be able to engage with the engaging protrusion 243, it is slightly longer than the engaging protrusion 243. It is sufficient if they are formed, and they need not be continuous.

In the above embodiment, the air inlet 24
0 is formed on the bottom surface of the outer case 2 and the filter cover 24
1 is slid horizontally from the bottom surface. However, the present invention is not limited to this. For example, an air inlet 240 may be provided on the side surface of the upper case 3 or the lower case 4. In this way, when arranged side by side,
There is an effect that the filter cover can be easily removed.

Further, in the above-described embodiment, the electro-optical device 925 includes the TFT driven liquid crystal panels 925R and 925.
G, 925B, but the present invention is not limited to this, and the present invention may be applied to a projection display device including a light modulation device configured by another driving method.

In the above embodiment, the electro-optical device 925 includes three liquid crystal panels 925R, 925G, 92
5B, the present invention is not limited to this, and the present invention may be applied to a light modulation device including one or two liquid crystal panels.

In the above embodiment, the electro-optical device 9
Although the panel constituting the liquid crystal device 25 is composed of a liquid crystal element, the present invention may be applied to a projection display device including a light modulation device composed of a plasma element other than a liquid crystal and a device panel using a micromirror. Good.

Further, the electro-optical device 925 in the above embodiment is of a type in which light fluxes R, G, and B are transmitted and modulated. However, the present invention is not limited to this. The present invention may be applied to a projection display device including a reflection-type light modulation device that emits light.

In addition, the specific structure, shape, and the like when implementing the present invention may be other structures and the like as long as the object of the present invention can be achieved.

[0079]

According to the present invention as described above, when the filter cover to which the air filter is attached is attached and detached,
Since the filter is removed along the surface of the outer case, the filter cover can be attached and detached even when the projection display devices are arranged in a stack. Therefore, the filter cover can be easily attached and detached even if the air intake of one projection display device is opposed to another adjacent projection display device among the plurality of projection display devices arranged in a stack. There is an effect that can be.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a projection display device according to an embodiment of the present invention as viewed from above.

FIG. 2 is an external perspective view of the projection display device according to the embodiment as viewed from below.

FIG. 3 is a perspective view illustrating an internal structure of the projection display device according to the embodiment.

FIG. 4 is a schematic diagram for explaining a structure of an optical system in the embodiment.

FIG. 5 is a perspective view showing components of the embodiment.

FIG. 6 is an external plan view of the projection display device and the filter cover in the embodiment as viewed from the bottom.

FIG. 7 illustrates a filter cover of the projection display device according to the embodiment, where (A) is a plan view of the filter cover,
(B) is a sectional view taken along line BB in (A).

FIG. 8 is an overall perspective view showing a filter cover of the projection type display device accommodating the air filter in the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Projection display apparatus 2 Exterior case 6 Projection lens 7 Power supply unit 8 Light source lamp unit 16 Exhaust fan 20 Rotation knob 40 Lens position adjustment mechanism 91 Ventilation member 160 Exhaust port 181 Light source lamp 240 Air intake 241 Filter cover 241G Guide groove 242 Air Filter 243 Engagement protrusion 244 Guide rail 245 Recess 925 Electro-optical device

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Nobuo Watanabe 3-3-5 Yamato, Suwa City, Nagano Prefecture Seiko Epson Corporation F-term (reference) 5C058 AB06 EA12 EA26 EA52 5G435 AA00 AA12 AA19 BB12 BB17 CC12 DD02 DD05 EE02 FF03 FF07 GG01 GG02 GG03 GG04 GG08 GG28 GG44 GG46 LL15

Claims (5)

[Claims] An electro-optical device for forming an optical image according to image information, a projection lens for enlarging and projecting an image formed by the electro-optical device, and an outer case for covering a main body including the electro-optical device. A projection type display device, comprising: a surface of the outer case, an air inlet for taking in external air into the outer case, and a filter cover attached with an air filter covering the air inlet, The projection display device, wherein the filter cover is detachable along a surface of the outer case in which the air intake is formed. 2. The projection display device according to claim 1, wherein said air intake is formed in a bottom surface of said outer case. 3. The projection display device according to claim 1, wherein one of the outer case and the filter cover is provided with a guide rail along a mounting / removing direction of the filter cover, and the other is provided with the guide. A projection display device comprising a guide groove for engaging with a rail. 4. The projection display device according to claim 3, wherein one of the outer case and the filter cover is provided with an engagement projection, and the other is provided with a recess engaged with the engagement projection. The projection type display device is formed, and the movement of the filter cover in the attachment / detachment direction is prevented by the engagement between the engagement protrusion and the recess. 5. The projection display device according to claim 1, wherein the filter cover is provided with a suppressing portion for preventing the air filter from projecting out of a plane. Characteristic projection display device.