1. A liquid crystal panel unit, comprising: a sealed container, made of a material with high thermal conductivity, having a light-transmissi~? .i.i.-do~; a liquid crystal panel accommodated in s&j. sealed container so as to allow light being transmitted to leave the light-transmission window; and a fan accommodated in said sealed container so as to be spaced from said liquid crystal panel.

2. A liquid crystal panel unit according to Claim 1, wherein the material with high thermal conductivity is a metal.

3. A liquid crystal panel unit according to Claim 1, further comprising a polarizing plate disposed in correspondence with the light-transmission window and at an outer side of said sealed container.

4. A liquid crystal panel unit according to Claim 1, wherein said fan is disposed such that the wind produced thereby does not directly hit the surface of said liquid crystal panel.

5. A liquid crystal panel unit according to Claim 1, further comprising heat radiating means provided at an outer side of said sealed container.

6. A liquid crystal panel unit according to Claim 5, wherein said heat radiating means 'is disposed at a location - 1 8 - other than where the light-transmission window is disposed.

7. A liquid crystal'.panel unit according to Claim 6, . . -rein said heat radiating means is at least one of a : 'sting fin, " heat pipe, and a Peltier element.

8. A liquid crystal projector, comprising: a liquid crystal panel unit including (i) a sealed container, made of a material with high thermal conductivity, having a light-transmission window, (ii) a liquid crystal panel accommodated in said sealed container so as to allow light being transmitted to leave the light-transmission window; and (iii) a fan accommodated in said sealed container so as to be spaced from said liquid crystal panel; and optical means for causing light to be incident to said liquid crystal panel, and enlarging and projecting light transmitted from said liquid crystal panel.

9. A liquid crystal projector according to Claim 8, wherein said optical means comprises a light source for illuminating said liquid crystal panel'and a projecting lens for projecting light transmitted from said liquid crystal panel.

10. A liquid crystal projector according to Claim 8, further comprising a screen for displaying thereon an image obtained by means of said liquid crystal panel

11. A liquid crystal projector according to Claim 8, I/ a 6 t - 1 9 - wherein said fan is disposed such that wind produced thereby I does not directly hit the surface of said liquid crystal panel.

12. A liquid crystal projector according to Claim 8, further comprising heat radiating means provided at an outer ~ ! side of said sealed container.

13. Liquid crystal panel unit substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

14. A liquid crystal projector substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

BACKGROUND OF THE INVENTION
1. .Field of the Invention
The present invention broadly relates to a liquid crystal
. .
panel unit, and, more particularly, t0.a liquid crystal panel
unit in which a.liquid crystal panel is more reliably cooled to
prevent the temperature of the panel from rising during
operation, and a liquid crystal projector utilizing such a
liquid crystal panel unit.
2. Description of the Related Art
The liquid crystal display (LCD) panel is known as one
providing an excellent display of a quality comparable to that
provided. by a cathode ray tube (CRT) . Such an LCD panel is
particularly advantageous compared to the CRT in that it can be
made thinner than the CRT, since it can provide a color display
merely by the,addition of a color filter for each image pixel
and by using an optical means such as an illuminating light
source.
However, during operation, the temperature of such a liquid
crystal panel rises when it receives light from a light source.
As the.liquid crystal panel becomes very hot, the polarization
plate melts, or the transition temperature of the liquid crystal
is exceeded, which may degrade display performance, such as
contrast, and reduce reliability. To overcome such problems,
such a liquid crystal panel, used for example in a liquid
crystil projector, is usually cooled, during operation, in order
to contro1,the extent to which the temperature of the liquid
crystal panel rises.
Conventional cooling structures for cooling a liquid
crystal panel include an air-cooling type structure and a
liquid-cooling type strkture
In a typical air-cooling type structure, a fan is disposed
near the liquid crystal panel to blow air to the liquid crystal
panel, as a result of which the liquid crystal panel is cooled.
In a typical liquid-cooling type structure, a liquid
crystal panel is previously accommodated in a suspended state in
a box to be filled with a cooling liquid. Then, the box is
filled with a cooling medium, such as silicone oil, within which
the liquid crystal panel is suspended. The liquid crystal panel
is cooled as a result of circulating the cooling medium.
However, a fan is used in the air-cooling type structure,
so that though the liquid crystal panel is cooled, dust is
produced around the liquid crystal panel, and sticks onto the
panel. When such a liquid crystal panel cooled by air is used,
for example, in a liquid crystal projector, the dust is
projected by the projector, thereby reducing the image quality.
In addition, since a fan is used, noise is generated by the fan
motor and blades of the fan in operation, thereby making the
projector in such a case a poor commercial product.
.. .
On the other hand, when cooling is performed using liquid,
problems such as liquid leakage may occur, or there may be a
transmission loss due to the index of refraction of the liquid,
leading to the possibility of deteriorations in optical
properties. In addition, it is difficult to produce a liquidcooling
structure in which the liquid is free from floating dust
or one in which the liquid does not leak, resulting in increased
costs.
SUMMARY OF THE 'INVENTION
In view of the above-described problems, an object of the
present invention is to provide a liquid crystal panel unit
which can reliably cool a liquid crystal panel, without any
deterioration in the image quality due to dust, and a liquid
crystal projector using the same.
To this end, according to one aspect of the present
invention, there is provided a liquid crystal panel unit,
comprising: a sealed container, made of a material with high
thermal conductivity, having a light-transmission window; a
liquid crystal panel accommodated in the sealed container so as
to allow light being transmitted to leave the light-transmission
window; and a fan accommodated in the sealed container so as to
be spaced from the liquid crystal panel.
In a preferred form of the invention, the material with
high thermal conductivity may be a metal.
In a preferred form of the invention, the liquid crystal
panel unit may further comprise a polarizing plate disposed in
correspondence with the light.-transmission window and at an
outer side of the sealed container.
In a preferred form of the invention, the fan may be
disposed such that the wind produced thereby does not directly
hit the surface of the liquid crystal panel.
In a preferred form of the invention, the liquid crystal
panel unit may further comprising heat radiating means provided
at an outer side of the sealed container.
In a preferred form of the invention, the heat radiating
means may be disposed at a location other than where the lighttransmission
window is disposed.
In a preferred form of the invention, the heat radiating
means may be at least one of a radiating fin, a heat pipe', and a
Peltier element.
According to the liquid'crystal panel unit of the present
invention, the liquid crystal panel and the fan are accommodated
in a sealed container, so that the liquid crystal panel can be
cooled by air, without having to introduce outside air into the
sealed container. In addition, since the iealed container is
made of metallic material, it obviously has high thermal
conductivity and is an excellent radiator of heat, so that heat,
generated within the sealed container during operation of the
liquid crystal panel, is transmitted to the sealed container by
wind produced by the.fan, and dissipated through and out the
sealed container with high efficiency. Further, since the 'fan
is acrommodated in the sealed container, noise produced during
operation of the fan, includingthe noise of the fan motor and
blades of the fan, is blocked by the sealed container, thus
reducing the noise level during operation of the fan.
According to another aspect of the present invention, there
is provided a liquid crystal projector, comprising: a liquid
crystal panel unit including (i) a sealed container, made of a
material with high thermal conductivity, having a lighttransmission
window, (ii) a liquid crystal panel accommodated in
the sealed container so as to allow light being transmitted to
leave the light-transmission~window;a nd (iii) a fan
accommodated in the sealed container so as to be spaced from the
liquid crystal panel; and optical means for causing light to be
incident to the liquid crystal panel, and enlarging and
projecting light transmitted from the liquid crystal panel.
In a preferred form of the invention, the optical means may
comprise a light source for illuminating the liquid crystal
panel and a projecting lens for projecting light transmitted
from the liquid crystal panel.
In a preferred form of the invention, the liquid crystal
projector may further comprise a screen for displaying thereon
an image obtained by means of the liquid crystal panel.
In a preferred form of the invention, the fan may be
disposed such that wind produced thereby does not directly hit
the surface of the liquid crystal panel.
In a preferred form of the invention, the liquid crystal
projector mayfurther comprise heat radiating means provided at
an outer side of the sealed container.
According to the liquid crystal projector of the present
invention, the above-described liquid crystal panel unit and the
above-described optical means are provided, so that cooling by
air can be performed, without introduction of outside air i'nto
the sealed container of the liquid panel unit, thus preventing
reduction in image quality due to dust.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic structural view of an embodiment of a
liquid crystal projector in accordance with the present
invention;
Fig. 2A is a sectional side elevational view of an
embodiment of a liquid crystal panel unit, while Fig. 2B is a
front elevational view of the embodiment of the liquid crystal
..
panel unit.
Fig. 3 is a sectional plan view of a first modification of
the liquid crystal panel unit.
Fig. 4 is a sectional plan view of a second modification of
the liquid crystal panel unit.
Fig. 5 is a sectional plan view of a third modification of
the liquid crystal panel unit.
Fig. 6 is a sectional plan view of a fourth modification of
the liquid crystal panel unit.
Fig. 7 is a sectional side elevationalview of the liquid
crystal panel unit used in an experiment.
DESCRIPTION OF.THE PREFERRED EMBODIMENTS
A description will now be given of the preferred
embodiments of the present invention.
Fig. 1 illustrates a liquid crystal projector in accordance
with the present invention. Referring to the Fig. 1, reference
numeral 1 denotes a liquid crystal projector including a liquid
crystal panel unit 2 , and optical means 3 which causes light to
impinge upon the liquid crystal panel unit 2 and the light
transmitted through the liquid crystal unit 2 to leave
theref.r. om.
The liquid crystal panel unit 2, in an embodiment of the
present invention, comprises a rectangular, sealed container 4,
~
p~-~ -- ~~ ~- --
, w !,
.a'
- 7 -
a liquid crystal panel 5, and a fan 6. The panel 5 and the fan
6 are both accommodated in the sealed container 4. The sealed
container 4 is made of metallic material with high thermal
conductivity, such as aluminum, copper, iron, or an alloy
thereof, so that the sealed container 4 is an excellent radiator
of heat. Light-transmissive windows 7 are provided on two
opposing and corresponding sides of the sealed container 4. The
windows 7 are made of transparent material which transmits
light, such as glass. The liquid crystal panel 5 is disposed
between the light-transmissive windows 7.
The light-transmissive windows 7 are bonded onto an opening
of the sealed container 4, with a soft and flexible adhesive
containing resin or the like, such as silicone rubber. Such an
adhesive prevents deformation of the sealed container 4, even
when it becomes hotter during operation of the liquid crystal
projector 1, since the adhesive absorbs the difference in the
coefficients of thermal expansion of the metallic portion of the
sealed container 4 and the light-transmissive windows 7 made of
glass or the like.
As will be described below,, the sealed container 4 makes it
possible to achieve noise insulation and to dissipate heat from
. .
the interior thereof. The sealed container must be - . thick in
order to achieve noise insulation, and have a large surface area
in order to allow heat dissipation. When the sealed container
is made thick, the light-transmissive window 7 must also be made
thicker. In such a case, the transmissivity is reduced by a
corresponding amount, so that both heat dissipation and noise
insulation are taken into account when determining how thick the
sealed container should be made
The liquid crystal panel 5 is disposed parallel to and
midway between the light-transmissive windows 7, 7, such that a
side end of the panel 5 is spaced from an inner side face of the
sealed container 4. The panel 5 is connected to an electrical'
power supply (not shown) to apply power thereto. In the liquid
crystal panel 5, polarizing plates are usually not provided on
the light incoming surface and the light outgoing surface of the
liquid crystal panel. Instead, polarizing plates 8 are provided
directly onto the outer surfaces of the light-transmissive
windows 7, as shown in Figs. 2A and 2B. Thus, the polarizing
plates are sufficiently cooled by outside air, when they are
h'eated during operation of the liquid crystal projector 1, as
will be described below.
The fan 6, being a small-sized microfan, is used to cool
the liquid crystal panel 5 by air. The electrical power supply
cord (not shown) is one which is led out from the sealed
container 4. In addition, the fan 6 is disposed between the
lower end face of the liquid crystal panel 5 and a bottom plate
4a of the sealed container 4, such that itsblowing side is
spaced from and faces the panel 5 in order to prevent vibrations
of the fan motor (not shown) from directly being transmitted to
the liquid crystal panel 5. With its sucking side spaced apart
from the bottom plate 4a, the fan 6 is affixed to the bottom
plate 4a of the sealed container 4, using vibration-proof,
sound-absorbing material 9, such as rubber, so as not to
obstruct operation thereof
By virtue of such a construction, the wind from the fan 6
rises along the front and back faces of the liquid crystal panel
5 while directly hitting the front and back faces, as indicated
C
by the arrows in Fig. 2A, duringwhich the wind takes away heat
from the liquid crystal panel 5, as a result of which the
temperature of the wind rises. The hotter wind hits the top
plate 4b or the like of the sealed container 4 and circulates
toward the fan 6, after which the wind is sucked in by the fan
6. Here, the wind exchanges heat with the top plate 4b, or the
like, of the sealed container 4, whereby the heat generated by
the liquid crystal panel 5 is dissipated out the sealed
container 4, as a result of which the liquid crystal panel 5 is
efficiently cooled.
As'illustrated in Fig. 1, the optical means.3 comprises a
concave mirror 10, a light source 11, a heat ray cut-off filter,
a convex lens 13, a reflecting mirror 14, and a projecting lens
15. The concave mirror 10 serves as a reflecting mirror. The
light source 11 is placed in front of the concave mirror 10.
The heat ray cut-off filter 12 is placed in front of the light
source.11. The convex lens 13 is placed in front of the heat
ray cut-off filter 12. The convex lens 13 is placed in front of
the reflecting mirror 14. The projecting lens 14 is placed in
front of the liquid crystal panel unit 5 which is disposed in
front of the reflecting mirror 14.
When such a liquid crystal projector 1 with the abovedescribed
construction is operated, light from the light source
11 is gathered by the concave mirror 10 and arrives at the heat
ray cut-off filter 12 which removes unwanted heat from the
light. The light, then, passes through the convex lens 13, the
reflecting mirror 14, and impinges upon the liquid crystal panel
unit 2, after which the light is linearly polarized by a
polarizing plate 8 disposed at the side where the light enters
the liquid crystal panel unit 2. Thereafter, the light in a
linearly polarized state passes through a light-transmissive
window 7 and impinges upon the liquid crystal panel 5, after
which the light is optically rotated in accordance with the
pattern of applying power to the panel 5 by previously applying
power to the liquid crystal panel 5. The light, then, passes
through the other light-transmissive window 7, and is repolarized
by the other polarizing plate 8 disposed at the side
where light leaves the liquid crystal panel unit. After passing
through the projecting lens 15, the image produced by optically
polarizing the light in accordance with the pattern of.applying
power to the panel 5 is enlarged and projected onto a screen
(not shown).
When the liquid crystal projector 1 operates as described
above, the liquid crystal panel 5 is heated by light with high
intensity, but is efficiently cooled in the sealed container 4
by air by means of the fan 6 accommodated in the sealed
container 4 in the same way as the light crystal panel 5.
~ccordingi~i,n the liquid crystal projector 1 of the
present embodiment, the liquid crystal panel unit 2 is so
constructed as allowing efficient cooling of the liquid crystal
panel 5. In addition, since the fan 6 is also accommodated in
the sealed container 4, normal operation of the liquid crystal
panel 5 is achieved by controlling the extent to which the
temperature of the panel 5 rises, without introduction of
outside air into the 'sealed container 4, and thus without dust
or the like in the outside air sticking onto the liquid crystal
panel 5, thus preventing deterioration of the image quality due
to dust sticking onto the panel 5.
The sealed container 4, which is made of a metal with high
thermal conductivity, dissipates heat 'very well. Therefore,
heat, generated during operation of the li'quid crystal panel 5
and transported to the inner surfaces of the sealed container 4
by means of the fan 6, is efficiently dissipated from the sealed
container 4, so that the liquid crystal panel 5 is cooled with
very high efficiency.
Since the £an 6 is disposed in the,sealed container 4, the
noise of the fan motor and blades of the fan, produced during
operation of the fan 6, are blocked by the sealed container 4,
thereby reducing the noise level during operation of the fan 6.
It is desirable to assemble the liquid crystal panel unit 2
in a clean environment, such as a clean room, so as to protect
the sealed container 4 from dust. In addition, it is preferable
to protect the component parts which are mounted to the liquid
crystal panel unit 2 from dust, during assemblage.
Fig. 3 is a sectional plan view of a modification of the
liquid crystal panel unit. The liquid crystal panel unit 20 of
Fig. 3 differs from the liquid crystal panel unit 2 of Fig. 2A
in that radiating fins are provided as radiating means on both
side faces of the sealed container 4. The radiating fins 21
allow the sealed container 4 to become an excellent radiator of
heat, so that the liquid crystal panel 5 can be cooled by means
of the fan 6 with even higher efficiency. Though the radiating
- 1 2 -
fins 21 have been described as being provided on both side faces
of the sealed container 4, they may be provided on one side
face, or the top face of the sealed container 4.
Fig. 4 is a sectional view of .a second modificationof the
liquid crystal panel unit. The liquid crystal unit 30 of Fig. 4
. .
differs from the liquid crystal panel unit 2 of Fig. 2A in that
a heat pipe 31 is provided as radiating means on one of the
sides of the sealed container 4. The heat pipe 31 is used for
transporting heat by absorption and discharge of latent heat by
evaporation and condensation, causing the sealed container 4 to
dissipate heat extremely well. Therefore, the liquid crystal
panel unit 30 is one in which the liquid crystal panel 5 is
cooled by means of the fan 6 with even higher efficiency, so
that such a construction makes it possible to make the sealed
container 4 more compact, or the like.
Fig. 5 is a sectional plan view of a third modification of
the liquid crystal panel unit. The liquid crystal panel unit 40
of Fig. 5 differs from the liquid crystal panel unit 2 of Fig.
2A in that a Peltier element 41 is provided as radiating means
on one of the sides of the sealed container 4. More
specifically, the cooling side of the Peltier element 41 is in
.. . . ..
contact with a side face of the sealed container 4, while the
radiating side of the element 41 is faced outward. Radiating
fins 42 are provided at the radiating side of the Peltier
element 41 in order to further increase the cooling (radiating)
effect of the Peltier element 41. Accordingly, the liquid
crystal panel unit 40 allows the liquid crystal panel 5 to be
cooled by means of the fan 6 with even higher efficiency.
- 13 -
Fig. 6 is a sectional plan view of a fourth modification of
the liquid crystal panel unit. The liquid crystal panel unit 50
of Fig. 6 differs from the liquid crystal panel unit 2. of Fig
2A in that necessary component parts 51 of the liquid crystal
projector, such as some of 'the component parts of the optical
means 3, are disposed within the sealed container 4 in order to
make the liquid crystal projector as a whole more compact.
Accordingly, the liquid crystal panel unit 51 as a whole can be
made more compact, and become an excellent commercial product.
Experimental Examples
Experiments were conducted to confirm the effects of the
liquid crystal panel unit in accordance with the present
invention as described below.
The liquid crystal panel unit was formed so as to have the
structure shown in Fig. 7. Referring to Fig. 7, reference
numeral 60 denotes a metallic sealed container; reference
numeral 61 denotes a liquid crystal panel; and reference numeral
62 denotes a fan. More specifically, in the liquid crystal
panel unit, the liquid crystal panel 61 was affixed to an inner
face of the sealed container 60, and the fan 62 was disposed at
one side of the liquid crystal panel 61 such that its blowing
- . .
side faced the liquid crystal panel 61. To cause the liquid
crystal panel 61 to generate heat, a ceramic heater (100V - 15W)
63 was affixed to the liquid crystal panel 61 so as to be
disposed at an outer side of the sealed container 60. In
addition, a temperature sensor 64 was mounted to the liquid
crystal panel 61 in order to measure the temperature of the
liquid crystal panel 61.
- 1 4 -
The dimensions of the sealed container 60 used were 165 x
235 x 75 mm. The fan 62 used was a microfan (SEPA MF30A-12)
manufactured by Nihon Keiki-sha.
The liquid crystal panel unit with the above-described
construction was used in the experiments. More specifically,
power was applied to the ceramic heater 63 to heat the liquid
crystal panel 61, and after the temperature of the liquid
cryqtal panel 61 was maintained at a constant level, power was
applied to the fan 62 by continually applying power to the
ceramic heater 63 in order to operate the fan 62.
Measurements were conducted ,of the voltages and currents
supplied to the fan 62, and of the wind speeds produced by the
fan 62. In addition, the temperatures of the liquid crystal
panel 61 for the measured voltages, currents, and wind speeds
were measured. The results are given in Tables 1, 2, and 3.
The results given in the three tables were obtained by varying
the amount of power applied to the ceramic heater 63.
TABLE 1 .
Heater 3.4 W
Liquid.Crysta1 Wind speed Fan Voltage Fan Current
Portion Temperature
95.4OC 0 m/s 0 V 0 mA
67.3OC 0.8 m/s 6 V 0.02 mA
61.3OC 1.5 m/s 8 V 0.03 mA
58.2OC 2.0 m/s 10 V 0.04 mA
56. O°C 3.0 m/s 12 V 0.05 mA
TABLE 2
Heater 2.7 W
Liquid Crystal Wind Speed Fan Voltage Fan Current
portion Temperature
84.4OC 0 m/s 0 V 0 mA
TABLE 3
Heater 2.2 W
Liquid Crystal Wind Speed Fan Voltage Fan Current
Portion Temperature
74.7OC 0 m/s 0 v 0 mA
55.0°C 0.8 m/s 6 V 0.02 mA
49.3OC 1.5 m/s 8 V 0.03 mA
46.2OC 2.0 m/s 10 V 0.04 mA
44.8OC 3 :0 m/s 12 V 0.05 mA
The results in Tables 1, 2, and 3 showed that the liquid
crystal panel 61 was sufficiently cooled by the fan 62
As can be seen from the foregoing description, according to
the liquid crystal .panel unit of the present invention, the
liquid crystal panel and the fan are accommodated in a sealed
container, allowing the liquid crystal panel tobe cooled by
air, without introduction of outside air into the sealed
container. In addition, since the sealed container is made of
metallic material which dissipates heat extremely well, heat of
the liquid crystal panel is dissipated through and out the
metallic sealed container with high efficiency.
In addition, since the fan is accommodated in a sealed
container, noise produced during operation of the fan, including
noise of the fan motor and blades of the fan, is blocked by the
container, thus making it possible to reduce the noise level,
during operation of the fan.
The liquid crystal projector comprises the above-described
liquid crystai panel unit and the above-described optical means.
Therefore, it is a projector in which the liquid crystal panel
unit is cooled by air, without introduction of outside air into
the sealed container, thus preventing a reduction in the image
quality due to dust. Accordingly, the liquid crystal projector
in accordance wit.h the present invention is an excellent
. ..
commercial product.
- 1 8 -
other than where the light-transmission window is disposed.
7. A liquid crystal panel unit according to Claim 6,
wherein said heat radiating means is at least one of a radiating
fin, a heat pipe, and a Peltier element.
8. A liquid crystal projector, comprising:
a liquid crystal panel unit including (i) a sealed
container, made of a material with high thermal conductivity,
having a light-transmission window, (ii) a liquid crystal panel
acconkodated in said sealed container so as to allow light being
transmitted to leave the light-transmission window; and (iii) a
fan accommodated in said sealed container so as to be spaced
from said liquid crystal panel; and
optical means for causing light to be incident to said
liquid crystal panel, and enlarging and prdjecting light
transmitted from said liquid crystal panel. . '
9. A liquid crystal projector according to Claim 8, wherein
said optical means comprises a light source for illuminating
said liquid crystal paneland a projecting lens for projecting
light transmitted from said liquid crystal panel.
10. A liquid crystal projector according to Claim 8,
further comprising a screen for displaying thereon an image
obtained by means of said liquid crystal panel.
11. A liquid crystal projector according to Claim 8 ,
13. Liquid.crysta1 panel unit substantially as hereinbefore
described with reference to and as illustrated in the accompanying
drawings.
30. A liquid crystal projector substantially as hereinbefore
- 1 9 -
wherein said fan is disposed such that wind produced thereby .. . .
does not directly hit the surface of said liquid crystal panel.
.
12. A liquid crystal projector accordingto Claim 8,
described with reference to and as illustrated in the accompanying
drawings.

WE CLAIMS:
1. A liquid crystal panel unit, comprising:
a sealed container, made of a material with high thermal
conductivity, having a light-transmissi~? .i.i.-do~;
a liquid crystal panel accommodated in s&j. sealed
container so as to allow light being transmitted to leave the
light-transmission window; and
a fan accommodated in said sealed container so as to be
spaced from said liquid crystal panel.
2. A liquid crystal panel unit according to Claim 1,
wherein the material with high thermal conductivity is a metal.
3. A liquid crystal panel unit according to Claim 1,
further comprising a polarizing plate disposed in correspondence
with the light-transmission window and at an outer side of said
sealed container.
4. A liquid crystal panel unit according to Claim 1,
wherein said fan is disposed such that the wind produced thereby
does not directly hit the surface of said liquid crystal panel.
5. A liquid crystal panel unit according to Claim 1,
further comprising heat radiating means provided at an outer
side of said sealed container.
6. A liquid crystal panel unit according to Claim 5,
wherein said heat radiating means 'is disposed at a location
- 1 8 -
other than where the light-transmission window is disposed.
7. A liquid crystal'.panel unit according to Claim 6,
. . -rein said heat radiating means is at least one of a : 'sting
fin, " heat pipe, and a Peltier element.
8. A liquid crystal projector, comprising:
a liquid crystal panel unit including (i) a sealed
container, made of a material with high thermal conductivity,
having a light-transmission window, (ii) a liquid crystal panel
accommodated in said sealed container so as to allow light being
transmitted to leave the light-transmission window; and (iii) a
fan accommodated in said sealed container so as to be spaced
from said liquid crystal panel; and
optical means for causing light to be incident to said
liquid crystal panel, and enlarging and projecting light
transmitted from said liquid crystal panel.
9. A liquid crystal projector according to Claim 8, wherein
said optical means comprises a light source for illuminating
said liquid crystal panel'and a projecting lens for projecting
light transmitted from said liquid crystal panel.
10. A liquid crystal projector according to Claim 8,
further comprising a screen for displaying thereon an image
obtained by means of said liquid crystal panel
11. A liquid crystal projector according to Claim 8,
I/
a
6
t
- 1 9 -
wherein said fan is disposed such that wind produced thereby
I does not directly hit the surface of said liquid crystal panel.
12. A liquid crystal projector according to Claim 8,
further comprising heat radiating means provided at an outer ~ !
side of said sealed container.
13. Liquid crystal panel unit substantially as hereinbefore
described with reference to and as illustrated in the accompanying
drawings.
14. A liquid crystal projector substantially as hereinbefore
described with reference to and as illustrated in the accompanying
drawings.