JP3528832B2 - LCD projector - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal projector for magnifying and projecting images on liquid crystal panels, and more particularly to a cooling structure for liquid crystal panels, lamps, polarizing plates and the like.

[0002]

2. Description of the Related Art Conventionally, a device for enlarging and projecting an image on a liquid crystal panel by using a lamp such as a metal halide has been put on the market. In this, light emitted from a light source is condensed on a liquid crystal panel via a mirror or the like and is projected on a screen through a projection lens.

Recently, a high-brightness one (a 1.3-inch liquid crystal is used to display a projected image on a large screen even in a bright room).
Optical output of 000 ANSI lumens), 0.9 type or 0.
An ultra-compact projector using a compact LCD such as 7-inch has also appeared.

As in the case of using a small panel, the smaller the liquid crystal is, the more intense the light from the light source is, and the more the light is condensed on the phase difference film of the liquid crystal, the polarizing plate, or the polarization conversion element (hereinafter referred to as PBS), so that the temperature is increased. It is said that the cooling method to lower the temperature is difficult.

As a method for cooling these liquid crystal panels, for example, as shown in FIG. 6, three liquid crystal panels 50 and respective polarizing plates 53 arranged on the incident side and the emitting side of the liquid crystal panels are used, and a cooling fan is used. A duct 58, which is branched into three in the gap between the liquid crystal panel and the polarizing plate by 57, is used to deliver air to the three liquid crystal panels (R portion at 58a, 58
B is blown to the G section and 58c is blown to the B section).

[0006]

In this way, the liquid crystal panel is provided between the entrance-side and exit-side polarization plates, and the air is sent to the RGB by using the branch ducts in the respective gaps by the cooling fan. Therefore, temperature control is difficult,
When a liquid crystal with a small size is used such as an ultra-small projector, it is not possible to take a lot of gaps (between the liquid crystal panel and the input / output polarization plate), the duct becomes complicated, and the ventilation resistance increases, so that the wind does not flow well.

As a result, the surface cooling of each liquid crystal panel and polarizing plate was incomplete, and the temperature rise could not be suppressed within the temperature specifications of each device (for example, 70 ° C. or less for liquid crystal panels). Similarly, the PBS and the lamp cannot control the temperature to a certain temperature or below without blowing air for temperature control, so a separate cooling fan was used for that purpose (not shown).

The present invention solves the above problems and efficiently cools a polarizing plate, a liquid crystal panel, a PBS, and a lamp with two fans. Particularly, one of the fans also serves to cool the PBS and the lamp. The present invention provides a liquid crystal projector having such a structure. Further, the present invention provides a liquid crystal projector having a structure in which the intake ports for the two fans and the filter in front of the intake ports are one.

[0009]

In order to solve the above-mentioned problems, a liquid crystal projector of the present invention comprises a lamp, a color separation means for separating the lamp into RGB, and three liquid crystal panels for respectively modulating the RGB light. A polarizing plate arranged on the entrance side and the exit side of the liquid crystal panel, and a polarization conversion element for converting the polarization of the light absorbed on the entrance side (P-polarized light) into the light that is transmitted in advance (S-polarized light). A first cooling fan for cooling the G light part and the B light part of the liquid crystal panel, the R light part of the liquid crystal panel, the polarization conversion element, or the R light part.
A second cooling fan that cools the light section, the polarization conversion element, and the lamp, and a suction port facing surface of the first cooling fan.
One of the air that is placed and sucked into the first cooling fan.
A guide duct that guides a portion to the second cooling fan, and a first air distribution unit that guides the intake air by branching the intake air from the first cooling fan to the G light portion and the B light portion of the liquid crystal panel. From the second cooling fan, the R light section of the liquid crystal panel and the polarization conversion element or the R light section, the polarization conversion element,
Second air distribution means for branching and guiding the intake air to the lamp, color combining optical means (X prism) for combining the modulated light, a projection lens for projecting the combined light, A lamp, the liquid crystal panel, the polarizing plate, the color separation means, the color combination optical means, the projection lens, the first and second cooling fans, etc. are included and closely contact with the suction port of the first cooling fan 1 It is characterized by comprising a main body case having two intake ports.

[0010] The first cooling fan is characterized in that a fan of the sirocco type.

Further, the color synthesizing optical means is characterized in that the first cooling fan is arranged on the GB portion side and the second cooling fan is arranged on the R portion side, and a guide duct is formed between them.

The first air distributing means and the second air distributing means are integrally formed.

With the above structure, the present invention provides a dedicated fan for G and B lights which receive particularly strong light in cooling the liquid crystal panel and the polarizing plate, and a relatively weak R light and PBS or even a lamp. Performed by one fan and placed 2
The two air distribution means are configured to be relatively straight to reduce ventilation resistance caused by the conventional duct.

As a result, the fan can be constructed in the same quantity as the conventional one, and the wind which has been conventionally blown to the R side can be circulated on the GB side, and the wind can be blown on the panel portion at a lower rotational speed than the conventional one. It is possible to reduce noise by being able to hit.

Further, since the two fans are connected by the guide duct, it is possible to provide a liquid crystal projector having a single intake port and capable of regularly cleaning the filter in one place. Furthermore, by integrating the above duct,
It is possible to configure without increasing the number of parts.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION A first aspect of the present invention is a lamp, and color separation means for separating the lamp into RGB.
Three liquid crystal panels for respectively modulating the RGB light, polarizing plates arranged on the incident side and the outgoing side of the liquid crystal panel, and a light (P-polarized light) that transmits the polarized light (P-polarized light) absorbed on the incident side in advance ( A polarization conversion element for converting to S polarization), a first cooling fan for cooling the G light section and the B light section of the liquid crystal panel, an R light section of the liquid crystal panel, the polarization conversion element, or the R light section. , the polarization conversion element, and a second cooling fan for cooling the lamp, the first cooling fan
Located on the opposite side of the suction port of the fan
Guide a part of the sucked air to the second cooling fan
Guide duct, first air distribution means for branching and guiding the intake air from the first cooling fan to the G light part and the B light part of the liquid crystal panel, and the liquid crystal from the second cooling fan. The R light section of the panel and the polarization conversion element or the R light section,
The polarization conversion element, the second air distribution means for branching and guiding the intake air to the lamp, the color combining optical means (X prism) for combining the modulated light, and the combined light are projected. Suction of the first cooling fan including the projection lens, the lamp, the liquid crystal panel, the polarizing plate, the color separation means, the color combining optical means, the projection lens, the first and second cooling fans, etc. Since the liquid crystal projector is composed of a main body case having one inlet close to the mouth, it has a dedicated fan for G and B lights that receive particularly strong light in cooling the liquid crystal panel and the polarizing plate, and is relatively weak. Cooling including R light and PBS or even a lamp is performed by one fan, and the two air distribution means are relatively straight in terms of arrangement to reduce ventilation resistance. It is possible to provide a liquid crystal projector configuration capable of configuring the panel cooled by the same quantity and.

Further, the first cooling fan is a sirocco type fan, and a guide duct for guiding a part of the air sucked into the first cooling fan from one intake port to the second cooling fan is provided with the first cooling fan. By disposing the first cooling fan on the GB portion side of the color synthesizing optical means and the second cooling fan on the R portion side of the color synthesizing optical means, and providing the guide duct between them, Since only one intake port can be provided, it is possible to provide a liquid crystal projector with a structure in which periodic filter cleaning can be performed in one place.

Further, since the first air distributing means and the second air distributing means are integrally formed, the two air distributing means and the guide duct are formed by one part without increasing the number of parts, and therefore cooling is performed. It is possible to provide a liquid crystal projector having an efficient cooling structure that can reduce noise by allowing air to leak to the outside and blowing air to the panel portion at a low rotation speed.

A liquid crystal projector according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a top perspective view showing a conceptual configuration of an optical section and a cooling section of a liquid crystal projector in an embodiment of the present invention. FIG. 2 is a perspective view of a configuration in which the lower case is removed from the back surface of FIG. 1, and FIG. 3 is a top perspective view in which two air distribution means of the present invention and a guide duct are integrated. Further, FIG. 4 is a perspective view showing a configuration when divided into three parts in FIG. 3 (by a chain line in the figure), FIG. 5 is a plan view showing an optical layout of the present embodiment, and FIG. 6 is a conventional example. FIG. 3 is an assembled perspective view of a part for cooling the liquid crystal panel in the liquid crystal projector of FIG.

The entire optical layout of the portion according to the present invention will be described with reference to FIGS. A general main configuration of a three-plate type liquid crystal projector optical system is that a light from a lamp (light source) 1 is converted into a plurality of mirrors 2 (reflection mirror, color separation mirror).
Is used for color separation into red, green, and blue, which is made incident on the liquid crystal panel unit 3, combined by the X prism 4 and the like, and enlarged and projected by the projection lens 5.

Three incident-side polarizing plates 7 and three outgoing-side polarizing plates 9 are provided in front of and behind the liquid crystal panel unit 3, and by controlling the potentials on and off of each pixel, all white,
Light amount control for all black and halftone is performed, and color synthesis is performed for each pixel. The liquid crystal panel unit 3 and each polarizing plate are formed on the optical base 10.

The lamp 1 and the mirrors 2 are held in the lower part 8 of the lighting case. Two lens arrays A12 and B13 for uniforming the brightness of the liquid crystal screen are provided between the lamp 1 and the mirrors 2 for color separation in the lower part 11 of the lighting case.
The lens array B13 also holds a PBS 14 that aligns polarized light from the lamp in one direction.

A strip-shaped retardation film 14a is adhered in order to align the polarization of the PBS 14. These optical components are prevented from coming off by an illumination upper case 15 (not shown) (detailed description of PBS is omitted).

The liquid crystal panel unit 3 also includes a prism 4
Is integrally provided with the metal fittings 16 and the like.
Is fixed after adjusting the convergence (pixel matching) of the three liquid crystal panels with a UV adhesive or the like.

As described above, the liquid crystal panel of the liquid crystal projector and the polarizing plate have an entrance side and an exit side with a certain space therebetween, and are generally air-cooled by the fan 11 or the like. All of these are held in the lower part 17 of the cab.

Next, the cooling structure will be described with reference to FIGS. 1 to 4. The heat inside the main body (especially the heat generated from the lamp) is exhausted by the exhaust fan 19. The exhaust fan 19 is fixed to the lower part 17 of the cabinet.

A filter 18 is provided at the outside air suction port, and the fan 11 sucks outside air into the main body while removing dust and the like. The fan 11 is usually a sirocco type.

As shown in FIG. 2, the air sucked from the fan 11 is provided with two holes 20 on the G and B sides of the liquid crystal panel and the polarizing plate where the light energy is large by the first air distribution means 20.
The air is discharged from a and 20b, and air is cooled on both surfaces of the polarizing plate and the liquid crystal panel.

Similarly, in the second air distribution means 21 directly connected to the second fan 23, by rotating the second fan 23, the air is discharged through the two holes 20c to the R side where the light energy of the liquid crystal panel is small. , The rest of the air is PBS
The air is sent to the holes 21d and the holes 21e for sending air to the lamps 14 and the lamps.

Holes 20a, 20b, 20c, 21d, 2
1e roughly corresponds to the arrangement of the optical components and the liquid crystal panel in FIG. The fan 11 sends air toward the first air distribution means 20 by rotation, but a part of the fan 11
It has a structure that allows air to escape to the side opposite to the part a filter.

From there, the guide duct 22 is in contact,
The air is sent to the guide duct 22 while hermetically sealing it. Therefore, a part of the outside air from the filter 18 passes through the second air distribution means 21 by the second fan 23 of the guide duct 22 and blows in the air.

In the present embodiment, this first air distribution means 2
Although the 0, the second air distributing means 21, and the guide duct 22 are integrally formed by molding, the first air distributing means 20,
The second air distributing means 21 and the guide duct 22 may be divided into A, B and C parts as shown by the one-dot chain line in FIG.

With the above construction, the duct becomes closer to straight than the conventional duct, and the air blown by the fan 11 and the second fan 23 flows with less ventilation resistance.

[0035]

As described above, according to the present invention, in a product in which a large amount of space cannot be provided between the liquid crystal panel and the input / output polarizing plate, as in the case of using a small liquid crystal such as a micro projector. In particular, the following effects are obtained.

In this structure, a dedicated fan for G and B lights, which receives particularly strong light in cooling the liquid crystal panel and the polarizing plate,
In addition, relatively weak R light and PBS, or even the lamp, including the lamp, is cooled by one fan, and the two air distribution means are configured to be relatively straight in terms of arrangement, thus reducing ventilation resistance, and as a result, the fan is also conventional. It is possible to provide a liquid crystal projector having a configuration capable of configuring panel cooling in the same quantity as.

The first cooling fan is a sirocco type fan, and the first cooling fan has a guide duct for guiding a part of the air sucked into the first cooling fan from one intake port to the second cooling fan. The first cooling fan is provided on the opposite side of the suction port, and on the GB section side of the color synthesizing optical means.
By disposing the second cooling fan on the side of the section and forming the guide duct between them, it is possible to provide a liquid crystal projector having a structure in which the intake port can be unified and the filter can be regularly cleaned in one place.

[Brief description of drawings]

FIG. 1 is a top perspective view of an optical unit and a cooling unit of a liquid crystal projector according to an embodiment of the present invention.

FIG. 2 is a perspective view of the configuration in which the lower case is removed when viewed from the back side in FIG.

FIG. 3 is a top perspective view of the duct in FIG. 2 seen from above.

FIG. 4 is a top perspective view of the duct as seen from above with the duct divided into three parts in FIG. 3;

FIG. 5 is a plan view showing an optical layout of this embodiment.

FIG. 6 is an exploded perspective view of a portion for cooling a liquid crystal part in a liquid crystal projector of a conventional example.

[Explanation of symbols]

1 lamp 2 mirror 3 LCD panel unit 4 X prism 5 Projection lens 7 Incident polarization plate 8 Under lighting case 9 Output polarizing plate 10 Optical base 11 fans 12 Lens array A 13 Lens array B 14 PBS 18 filters 19 exhaust fan 20 First air distribution means 21 Second Air Distribution Means 22 Guide duct 23 Second Fan

Continuation of front page (51) Int.Cl. ⁷ identification code FI G03B 21/14 G03B 21/14 E 21/16 21/16 (56) Reference JP-A-2001-228803 (JP, A) JP-A-2003-66533 (JP, A) JP 2003-66534 (JP, A) JP 2001-33750 (JP, A) JP 2001-133885 (JP, A) JP 2000-81673 (JP, A) JP 4-A 368987 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G02F 1/13 505 G02F 1/1333 G02F 1/1335 G02F 1/13357 G03B 21 / 00-21 / 30 G03B 33 / 00-33/16 H04N 5/66-5/74

Claims (3)

(57) [Claims] 1. A lamp, color separating means for separating the lamp into RGB, three liquid crystal panels for respectively modulating the RGB light, and polarizing plates arranged on an incident side and an emitting side of the liquid crystal panel. A polarization conversion element for converting polarized light (P polarized light) absorbed on the incident side into light (S polarized light) that is transmitted in advance, and a first cooling fan for cooling the G light portion and the B light portion of the liquid crystal panel. A second cooling fan for cooling the R light section of the liquid crystal panel, the polarization conversion element or the R light section, the polarization conversion element, the lamp; and a suction port facing surface of the first cooling fan. Placed and said
A part of the air sucked into the first cooling fan is transferred to the second cooling fan.
A guide duct for guiding a cooling fan, and the G light section of the liquid crystal panel from the first cooling fan, B
A first air distribution means for branching and guiding the intake air to a light section; an R light section of the liquid crystal panel from the second cooling fan and the polarization conversion element or R light section; the polarization conversion element; Second air distribution means for branching and guiding the intake air to the lamp, color combining optical means (X prism) for combining the modulated light, a projection lens for projecting the combined light, and the lamp A liquid crystal panel, the polarizing plate, the color separating unit, the color combining optical unit, the projection lens, the first and second cooling fans, and the like, which are in close contact with the suction port of the first cooling fan. A liquid crystal projector consisting of a main body case having an intake port. 2. A first cooling fan liquid crystal projector according to claim 1, characterized in that the fan of the sirocco type. 3. The liquid crystal projector according to claim 1, wherein a first cooling fan is arranged on the GB part side of the liquid crystal panel and the polarizing plate, a second cooling fan is arranged on the R part side, and a guide duct is formed between them.