JP3448492B2 - Liquid crystal panel and projection device using the liquid crystal panel - 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 panel and a projection device that illuminates the panel with strong light to illuminate an image on a screen.

[0002]

2. Description of the Related Art Conventionally, there has been known a projection device which irradiates a liquid crystal panel (7) with strong light to illuminate an image on a screen. FIG. 8 is a side view showing a basic configuration of such a projection device. Is. The light from the light source (2) is condensed by the first and second integrator lens bodies (41) and (42) and the condenser lenses (43) and (44), and then illuminates the liquid crystal panel (7). Figure 9
FIG. 3 is a cross-sectional view of the liquid crystal panel (7) as seen from the side. The liquid crystal panel (7) has two transparent substrates (5) and (5) slightly separated from each other and a liquid crystal (51) enclosed between the two substrates. (5) The peripheral portion between (5) is closed with the sealant (50). On the outside of each substrate (5) (5), a polarizing plate (9) that allows only one of the undefined polarized lights to pass through.
(9) is provided. Since the light from the light source (2) is strong, the substrates (5) (5) and the polarizing plate (9) are easily overheated,
As a result, the image function may deteriorate and the durability may decrease. Therefore, normally, the substrates (5) (5) and the polarizing plate (9) are air-cooled from below or from the side.

[0003]

In recent years, such a device is required to have higher brightness, and the light emitted from the light source (2) is also intense. Therefore, the substrate (5) (5) and the polarizing plate
In the case of (9), thermal damage is more likely to occur, and it is required to improve the cooling effect. Generally, to increase the air cooling effect,
It is conceivable to attach a heat dissipation member. The applicant is
It was conceived that the cooling effect would be high if the parts other than the part irradiated with the substrates (5) and (5) were covered with a heat dissipation member. The present invention is
The purpose is to enhance the cooling effect of the substrate (5) (5) or the polarizing plate (9) of the liquid crystal panel (7).

[0004]

[Means for Solving the Problems] A liquid crystal panel has a structure in which a liquid crystal (51) is sealed between two transparent substrates (5) and (5), and both substrates (5) are sealed.
(5) is sandwiched between holding cases (8) and (8), and each holding case
In (8), there is an opening (81) that allows the transmission of light to the substrates (5) and (5).
It is opened, and the polarizing plate (9) (9) is arranged on each holding case (8) (8).
Be prepared. Outer surfaces of the holding case (8) (8) is double
Heat dissipation fin (80) constructed by connecting a number of protrusions (84) (84)
Forming (80). Polarizing plate (9) is for each heat radiation fin (80)
Adjacent to the protrusion (84) attached to the tip of the protrusion (84)
Provided below the substrates (5) and (5) between the (84) and the polarizing plate (9).
A closed space where cooling air from the fan (33) flows
It is.

[0005]

[Operation and effect] The substrates (5) and (5) are sandwiched by holding cases (8) and (8) integrally formed with the heat radiation fins (80).
The polarizing plate (9) is contacted on the outside or inside of the heat dissipation fin (80).
ing. Therefore, with the strong light from the light source (2), the liquid crystal panel
Even if the substrate (5) (5) of (7) and the polarizing plate (9) are irradiated, overheating of the substrate (5) (5) or the polarizing plate (9) of the liquid crystal panel (7) is prevented, and thermal damage is caused. Can be prevented. Particularly, if the opening (81) of the holding case (8) is made as small as possible corresponding to the minimum irradiation area of the substrate (5), the air cooling effect of the heat radiation fin (80) is further improved.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION An example of the present invention will be described in detail below with reference to the drawings. The same reference numerals are used for the same configurations as the conventional ones. FIG. 5 is a plan view of the projection apparatus. The projection apparatus irradiates three liquid crystal panels corresponding to the three primary colors of light, R, G, and B, with strong light, and then synthesizes the light to form a screen. Project an image. A chassis (3) for holding three liquid crystal panels (7) (7a) (7b) is provided in the cabinet (6), and a projection lens (67) is provided at the front end of the chassis (3). ing. A prism body (30) is provided in the chassis (3) coaxially with the optical axis of the projection lens (67).
The liquid crystal panels (7a) and (7b) corresponding to R and B are arranged with the (0) in between. The prism body (30) has a reflection layer (31) inside, and a liquid crystal panel (7) corresponding to G is provided on the opposite side of the projection lens (67) with the prism body (30) interposed therebetween. .
A light source (2) is installed at the entrance of the chassis (3), and total reflection mirrors (75) (76) (77) (78) and dichroic mirrors (45) (46) are tilted in the optical path on the optical path. It has been deployed. In the following description, the direction in which light is emitted from the light source (2) and heads for the prism body (30) is referred to as the front.

The light from the light source (2) is condensed by the first and second integrator lens bodies (41) and (42) and the condenser lens (43) and then reflected by the total reflection mirror (75). The dichroic mirror (45) allows R to pass through and reflects G and B. The R is reflected by the total reflection mirror (76) and illuminates the liquid crystal panel (7a) corresponding to the R. G is reflected by the dichroic mirror (46) and enters the prism body (30). B is reflected by the total reflection mirrors (77) and (78) and then reflected by the reflection layer (31) in the prism body (30) and enters the projection lens (67). R, G, B in the prism body (30)
The three color lights of are combined and projected on the screen (68).

(First Embodiment) FIG. 1 is an exploded perspective view of a liquid crystal panel (7), and FIG. 2 is a sectional view of the same taken along line AA. The liquid crystal panel (7) comprises holding cases (8), (8) butted against each other, and two transparent substrates (5, 5) facing each other are sandwiched between the holding cases (8), (8). is doing. A liquid crystal (51) is sealed in a gap between both substrates (5) and (5), and a peripheral portion between both substrates (5) and (5) is closed with a sealant (50). On the outer side of the holding case (8), there is formed a heat radiation fin (80) in which a plurality of protrusions (84) (84) are arranged in a row in a row, and the holding case (8) and the heat radiation fin (80) are made of aluminum die casting. Alternatively, it is integrally formed by processing a copper plate. Aluminum or copper is used as the material of the holding case (8) and the heat dissipation fin (80) because the thermal conductivity of aluminum is 236 (1 / W · m ⁻¹ · K ⁻¹ ), and the thermal conductivity of copper is Is 403 (1 / W · m ⁻¹ · K ⁻¹ ), which is higher in thermal conductivity than other metals such as iron and has a high heat dissipation effect.

The central portion of the heat dissipation fins (80) (80) is an opening (81)
The light from the outside enters the two substrates (5) and (5) through the opening (81). LCD panel as before
Reference numeral (7) includes polarizing plates (9) and (9), and the polarizing plates (9) and (9) are attached to the tips of the heat radiation fins (80) to cover the openings (81).
As is well known, the polarization directions of the polarizing plates (9) and (9) are orthogonal to each other, and when power supply and cutoff to the liquid crystal (51) sealed between the substrates (5) and (5) are switched, The image is displayed after switching between blocking and passing.

Since the light source (2) emits strong light, it is easily overheated. Therefore, in this example, the holding case having the fins (80) for heat radiation on the substrate (5) (5) and the polarizing plate (9).
(8) is attached to enhance the cooling effect. Therefore,
The strong light from the light source (2), the substrate (5) of the liquid crystal panel (7)
Even if (5) and the polarizing plate (9) are irradiated, overheating of the substrates (5) (5) and the polarizing plate (9) can be prevented, and thermal damage can be prevented. Particularly, if the opening (81) is made as small as possible corresponding to the minimum irradiation area of the substrate (5), the air cooling effect of the heat radiation fin (80) is further improved. Incidentally, a transparent conductive film (not shown) may be formed on the substrate 5 to further enhance the thermal conductivity. Also,
Polarizing plates (9) and (9) are provided inside the holding case (8) in contact with the substrate (5) instead of outside the holding case (8) as shown by the one-dot chain line in FIG. Is also good. Further, a leaf spring (82) is provided on the inner surface of one of the holding cases (8), so that the board (5)
(5) may be pressed against the other holding case (8).

FIG. 6 is a vertical cross-sectional view showing how the liquid crystal panel (7) is attached to the chassis (3). An opening (32) is formed on the chassis (3) below the liquid crystal panel (7),
A fan (33) is provided below the opening (32). The liquid crystal panel (7) is air-cooled by the fan (33), and the cooling effect is enhanced by the heat radiation fins (80). Here, as shown in FIG. 5, three liquid crystal panels (7), (7a), and (7b) are provided on the chassis (3), and the opening (32) is provided in each liquid crystal panel (7). It is opened in correspondence with (7a) and (7b). The fan (33) cools the three liquid crystal panels (7) (7a) (7b) through the openings (32) (32) (32), but the cooling air from the fan (33) is for heat dissipation. Ascends between the protrusions (84) of the fin (80). As a result, one fan (33) can cool the liquid crystal panels of the three liquid crystal panels (7) (7a) (7b). That is, as shown in FIG. 5, each liquid crystal panel (7) (7a) (7b)
The installation position is different by 90 degrees from the adjacent liquid crystal panels, and if the fan (33) is used, each liquid crystal panel (7) (7a)
When installed on the side of (7b), three liquid crystal panels (7) (7a)
It is difficult to cool (7b) at once. Therefore, the fan (3
3) was installed under the liquid crystal panels (7) (7a) (7b).

(Second Embodiment) FIG. 3 is a plan sectional view of a liquid crystal panel (7) according to another embodiment. This is the board (5)
Attach the transparent glass plate (55) (55) for dust protection to (5),
This is sandwiched between the holding cases (8) and (8). By forming this glass plate (55) (55) with sapphire glass or the like having a high thermal conductivity, the heat of the substrate (5) is transferred to the glass plate (5).
5) The heat is easily transmitted to the heat radiation fins (80) via the (55) to enhance the cooling effect. Here, although the thermal conductivity of sapphire glass varies depending on the composition ratio of the glass,
The thermal conductivity of general soda glass is 0.55-0.
It is a value larger than 75 (1 / W · m ⁻¹ · K ⁻¹ ), and has a larger cooling effect than forming the glass plates (55) and (55) with soda glass. The substrate (5) may be made of sapphire glass. Further, a transparent conductive film (not shown) may be formed on the glass plate (55) to further increase the thermal conductivity. Furthermore,
As described above, the transparent conductive film may be formed on the substrate (5), or the polarizing plates (9) and (9) may be provided inside the holding case (8) instead of being provided outside the holding case (8). May be provided in contact with the substrate (5).

(Third Embodiment) FIG. 4 is a plan sectional view of a liquid crystal panel (7) according to another embodiment. In this example,
The edges of the two substrates (5) (5) are made of a plastic frame.
It is held by (52) (see FIG. 7), and on the outside of each substrate (5) (5),
An intermediate member (95) made of a transparent and high thermal conductivity material such as sapphire glass is in contact with the material. The intermediate member
Outside of (95), the central part has an opening (81) and a mountain-shaped protrusion (84).
A first heat-radiating fin (80) formed by connecting the first heat-radiating fin (80) and the second heat-radiating fin (80) having the same shape as the first heat-radiating fin (80). A fin (83) is attached. First heat dissipation fin (80) and second heat dissipation fin
The apexes of the protrusions (84) of the (83) abut each other, and a closed space (85) is formed between the protrusions (84) adjacent to each other. Cooling air flows vertically through the closed space (85). In this way, the first heat radiation fins (80) and the second heat radiation fins (83) are provided to increase the area of the portion that comes into contact with air and enhance the cooling effect. A glass plate (86) is provided on the outside of the second heat dissipation fin (83), and is located inside the opening (81) of the second heat dissipation fin (83) on the inner surface of the glass plate (86). A polarizing plate (9) is attached. The polarizing plate (9) may be directly attached to the outside of the second heat radiation fin (83).

The above description of the embodiments is for explaining the present invention, and should not be construed as limiting the invention described in the claims or reducing the scope. The configuration of each part of the present invention is not limited to the above-mentioned embodiment, and it goes without saying that various modifications can be made within the technical scope described in the claims.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a liquid crystal panel.

FIG. 2 is a plan sectional view of the above.

FIG. 3 is a plan sectional view of a liquid crystal panel according to another embodiment.

FIG. 4 is a plan sectional view of a liquid crystal panel according to another embodiment.

FIG. 5 is a plan view of the projection device.

FIG. 6 is a vertical cross-sectional view showing the positional relationship between the liquid crystal panel on the chassis and the fan.

FIG. 7 is a perspective view of a substrate supported by a frame.

FIG. 8 is a side view showing the basic configuration of the projection device.

FIG. 9 is a side sectional view of a liquid crystal panel.

[Explanation of symbols]

(2) Light source (3) Chassis (5) Substrate (7) LCD panel (9) Polarizing plate (51) LCD (55) Glass plate (80) Heat dissipation fin

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G02F 1/13-1/141

Claims (3)

(57) [Claims] 1. A liquid crystal (51) between two transparent substrates (5) (5).
Then, both substrates (5) and (5) are sandwiched between holding cases (8) and (8).
Each holding case (8) holds light through the substrate (5) (5).
An opening (81) that allows the passage of light is opened, and polarization is applied to each holding case (8).
In a liquid crystal panel configured by arranging a plate (9) , a plurality of protrusions (84) (84) are provided on the outside of both holding cases (8) (8).
The heat-radiating fins (80) (80) formed in series are formed, and the polarizing plate (9) is attached to the tip of the protrusion (84) of each heat-radiating fin (80).
Of the protrusions (84) (84) and the polarizing plate (9) that are attached and are adjacent to each other
In between, from the fan (33) installed below the substrate (5) (5)
A liquid crystal panel characterized by forming a closed space through which cooling air flows . 2. A glass plate (55) made of sapphire glass having a large thermal conductivity among glass materials is attached to at least one of the heat radiation fin (80) and the substrate (5). The liquid crystal panel described in. 3. A light source (2) and a light source in the chassis (3).
A spectroscopic means for spectroscopically dividing the light from (2) into R, G, and B;
Liquid crystal panels (7), (7a), (7b) corresponding to G and B lights,
The liquid crystal panel (7) (7a) (7b) is provided with a synthesizing means for synthesizing the light emitted, and a projection lens (67) for photographing the synthesized light,
The liquid crystal panels (7) (7a) (7b) are two transparent substrates (5) (5)
Liquid crystal (51) is enclosed between them to hold both substrates (5) and (5)
(8) It is sandwiched by (8) and each holding case (8) has a substrate (5)
An opening (81) is opened to allow the transmission of light to (5), and each holding case
In the projection device configured by disposing the polarizing plates (9) and (9) on the bases (8) and (8) , the fan (33) is provided below the substrates (5) and (5). A plurality of protrusions (84) (84) are provided on the outside of both holding cases (8) (8).
The heat-radiating fins (80) (80) formed in series are formed, and the polarizing plate (9) is attached to the tip of the protrusion (84) of each heat-radiating fin (80).
Of the protrusions (84) (84) and the polarizing plate (9) that are attached and are adjacent to each other.
In between, a closed space where cooling air from the fan (33) flows is formed.
Projection apparatus characterized by being.