Liquid crystal cell and method for producing the same in which a liquid crystal inlet port opening width is larger than an effective display area width

A liquid crystal cell includes a color filter substrate and an opposite substrate which are overlapped on each other with a seal interposed therebetween. The seal has a liquid crystal inlet port through which liquid crystal is filled into a space enclosed by the seal between the substrates. A width of the liquid crystal inlet port is made wider than a width of an effective display area of the liquid crystal cell, so that, when the liquid crystal is filled into the liquid crystal cell, the liquid crystal flows uniformly without disturbing an orientation of the liquid crystal.

CROSS REFERENCE TO RELATED APPLICATIONS 
This application is based upon and claims the benefit of priority of the 
prior Japanese Patent Applications No. Hei. 7-243401 filed on Sep. 21, 
1995, and NO. Hei. 8-172554 filed on Jul. 2, 1996, the contents of which 
are incorporated herein by reference. 
BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention generally relates to liquid crystal cells into which 
various types of liquid crystal, such as smectic liquid crystal or the 
like, are filled. The present invention also relates to methods for 
producing the same. 
2. Related Arts 
In a conventional method for producing a liquid crystal cell, as shown in 
FIG. 21 (refer to JP-A-4-316021), smectic liquid crystal 4 is filled into 
a space between electrode substrates 1 and 2 which are overlapped on each 
other with a band-like seal 3 interposed threrebetween. To fill the liquid 
crystal 4 into the liquid crystal cell, the smectic liquid crystal 4 is 
dropped around a liquid crystal inlet port 3a of the seal 3 and heated to 
be softened, thereby closing the liquid crystal inlet port 3a, while the 
electrode substrates 1 and 2 are disposed under vacuum in a vacuum 
chamber. Thereafter, the vacuum chamber is opened to an atmospheric 
pressure, so that a pressure difference between the outside and the inside 
of the space between the electrode substrates 1 and 2 is produced. 
Accordingly, the smectic liquid crystal 4 is absorbed into and fills the 
space between the electrode substrates 1 and 2. 
However, in the conventional method for filling the liquid crystal, as 
mentioned above, the liquid crystal inlet port 3a is formed on a central 
portion of a side of the seal 3. Therefore, as shown in FIG. 21, the 
smectic liquid crystal 4 entered the space between the electrode 
substrates 1 and 2 through the liquid crystal inlet port 3a can not flow 
uniformly, and, accordingly, spreads out in a crosswise direction of the 
inlet port 3a. 
On the other hand, an alignment film is formed on the electrode substrates 
by a rubbing treatment so that an axis of each liquid crystal molecule of 
the smectic liquid crystal 4 is oriented in a rubbing direction. 
When the smectic liquid crystal spreads out in the crosswise direction of 
the inlet port 3a, the liquid crystal flows in different directions from 
the rubbing direction of the alignment film. Accordingly, the smectic 
liquid crystal positioned close to the inlet port 3a is oriented 
differently from the smectic liquid crystal at other positions oriented in 
the rubbing direction. In other words, the liquid crystal filled in the 
space can not be oriented uniformly. As a result, there occurs a problem 
that the liquid crystal cell having such an irregularly oriented liquid 
crystal produces an uneven display. 
SUMMARY OF THE INVENTION 
The present invention has been made in view of the above mentioned problem 
and it is an object of the present invention to provide a liquid crystal 
cell capable of producing an even display. More particularly, it is an 
object of the present invention to provide structures and methods for 
filling liquid crystal into a space between both electrode substrates, 
thereby providing a liquid crystal cell in which the liquid crystal is 
filled with an uniform orientation. 
According to one aspect of the present invention, in a liquid crystal cell 
including a first and a second electrode substrate overlapped on each 
other, liquid crystal filled into a space between the first and second 
substrates, and a seal with a liquid crystal inlet port, a width of the 
liquid crystal inlet port is made larger than a width of an effective 
display area of the liquid crystal cell, so that the liquid crystal can be 
smoothly filled into the space between the two substrates with a uniform 
orientation. 
Further, the liquid crystal cell includes a plurality of small dam seals 
formed dispersively in the liquid crystal inlet port with a predetermined 
shape, such as a column shape, a streamline shape, or the like, so that no 
filling marks remain in the liquid crystal cell when the liquid crystal is 
filled into the liquid crystal cell. 
Further, a gap between both of the electrode substrates in an area between 
the liquid crystal inlet port and the effective display area is larger 
than that in the effective display area. 
Furthermore, the liquid crystal cell includes stripes of resist pillars 
formed between both of the electrode substrates, the pillars stretching to 
a direction of the liquid crystal filling flow, so that the gap between 
the two electrode substrates can be kept accurately and the liquid crystal 
flows smoothly when it is filled into the gap. 
According to another aspect of the present invention, there is provided an 
improved method of producing the above mentioned liquid crystal cell. The 
method includes a step of forming the seal on one of the electrode 
substrates with the liquid crystal inlet port, the opening width of which 
is larger than that of the effective display area, a step of overlapping 
the electrode substrate on the other electrode substrate, and a step of 
filling the liquid crystal into the gap between the two substrates through 
the liquid crystal inlet port so that a flow of the liquid crystal is 
substantially uniform. 
Further, the method includes a step of forming dam seals dispersively in 
the liquid crystal inlet port before the step of overlapping the electrode 
substrates, so that the dam seals do not disturb the flow of the liquid 
crystal. 
Further, the method includes a step of forming an additional dummy seal 
before the electrode substrates are overlapped. 
Furthermore, the liquid crystal cell has its orientation control direction, 
so that the liquid crystal is filled generally parallel to the orientation 
control direction. 
By employing the constructions and using the methods according to the 
present invention, the liquid crystal is filled uniformly into the liquid 
crystal cell gap through the liquid crystal inlet port without any 
stagnation, and the cell gap is kept appropriately at the same time. As a 
result, molecules of the liquid crystal are uniformly oriented without 
leaving any filling marks in the liquid crystal cell, and thus a uniform 
display with a high contrast can be attained.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EXEMPLARY EMBODIMENTS 
Embodiments according to the present invention will be described 
hereinunder with respect to the drawings. 
A first embodiment of the present invention will be described on the basis 
of FIGS. 1 to 6. 
FIG. 1 shows manufacturing processes of a liquid crystal cell of the first 
embodiment according to the present invention. First, in an original color 
filter substrate formation process S1, an original substrate 10A for 
constituting a color filter substrate 10 (see FIG. 4) is formed as shown 
in FIG. 3. The original substrate 10A is formed by laminating thin film 
layers on a transparent glass substrate 11. The layers on the glass 
substrate 11 are, counting from the surface of the glass substrate 11, 
color filters 12 consisting of a plurality of stripes, a protection film 
13, transparent electrodes 14 consisting of a plurality of stripes, an 
insulating film 15, and an alignment film 16. 
On the alignment film 16 of the original substrate 10A, a rubbing treatment 
(orientation control treatment) is performed in a direction indicated by 
an arrow A10 in FIG. 5. 
In an original opposite substrate formation process S2, an original 
substrate 20A for constituting an opposite substrate 20 (see FIG. 4) is 
formed as shown in FIG. 3. The original substrate 20A is formed by 
laminating thin film layers, transparent electrodes 22 consisting of a 
plurality of stripes, an insulating film 23, and an alignment film 24, on 
an transparent glass substrate 21 in this order. 
On the alignment film 24 of the original substrate 20A, the rubbing 
treatment is performed in a direction opposite to the rubbing direction of 
the alignment film 16 (a direction indicated by an arrow A20 in FIG. 5). 
Next, in a seal printing process S3, a generally U-shaped stripe of a seal 
30 is printed on the insulating film 15 around a vicinity of the outer 
periphery of the alignment film 16 as shown in FIGS. 2 and 3. 
The seal 30 is composed of an upper side 32, a lower side 33 and a right 
side 34, and an opening as a liquid crystal inlet port 31 is provided at 
the left side thereof as shown in FIG. 2. An opening width W1 of the 
liquid crystal inlet port 31 is made larger than a width W2 of an 
effective display area R of the liquid crystal cell (an area enclosed by a 
two-point chain line in FIG. 5) as shown in FIG. 5. The effective display 
area R corresponds to an area where the alignment films 16 and 24 exist. 
A dummy seal 40 is also printed on the insulating film 15 parallel to a 
scribe-line L1 which will be explained later. A length of the dummy seal 
40 is generally equal to the opening width W1 of the liquid crystal inlet 
port 31. The shape of the dummy seal 40 is not limited to the straight 
line, but may be changed to any suitable shape. 
Next, in a spacers and fine-grained adhesives scattering process S4, plural 
spacers and fine-grained adhesives (not shown) are scattered on the 
alignment film 24 of the original substrate 20A. 
Thereafter, in an overlapping process S5, the original substrate 20A is 
overlapped on the original substrate 10A with the seal 30, the dummy seal 
40, the spacers, and the fine-grained adhesives interposed therebetween. 
In a seal hardening process S6, thus overlapped original substrates 10A and 
20A are heated while a pressure or load is applied thereto, whereby the 
seal 30 and the dummy seal 40 are hardened. In this case, as the dummy 
seal 40 is formed as mentioned above, a gap between the substrates 10A and 
20A can be kept appropriately despite of the load applied to the 
substrates. 
After the seal hardening process S6, cutting process S7 is performed. In 
this process, the scribe-lines L1 to L4 are scribed on the original 
substrate 10A as shown in FIG. 2 so that the original substrate 10A can be 
cut into a shape of the color filter substrate 10 as shown in FIG. 4. 
Further, the scribe-lines are scribed on the original substrate 20A so 
that the original substrate 20A can be cut into a shape of the opposite 
substrate 20 as shown in FIG. 4. 
Next, the original substrates 10A and 20A are cut along the scribe-lines. 
Cut-out portions of the original substrates 10A and 20A are removed, 
whereby the liquid crystal cell composed of the color filter substrate 10 
and the opposite substrate 20 without the liquid crystal therebetween is 
completed as shown in FIG. 4. The dummy seal 40 is removed together with 
the cut-out portions. 
Next, in a liquid crystal filling process S8, as shown in FIGS. 4 and 5, 
members 50a and 50b for stopping a flow of the liquid crystal are formed 
on both ends of the liquid crystal inlet port 31. The stopping members 50a 
and 50b are made of a resin which is hardened by an ultra violet ray. 
Thereafter, droplets of antiferroelectric liquid crystal 60 are placed 
dispersively at the inlet port 31 on an inner surface of the color filter 
substrate 10 as shown in FIG. 4. The droplets of antiferroelectric liquid 
crystal 60 is prevented from flowing outward by the stopping members 50a 
and 5Ob. 
The liquid crystal cell carrying the droplets of antiferroelectric liquid 
crystal 60 is disposed in a chamber 71 of a liquid crystal filling device 
70 (see FIG. 6). In the chamber 71, the liquid crystal cell is held by 
cell holders 72. 
In this state, an exhaust valve 73 is opened, so that a pressure in the 
chamber 71 is reduced to 5.times.10.sup.-4 Torr. Thereafter, the liquid 
crystal cell is heated by far infrared ray heaters 75.degree. to 
120.degree. C. When a temperature of the antiferroelectric liquid crystal 
60 exceeds its transition temperature in which the liquid crystal 60 
transforms into an isotropic phase (e.g., 85.degree. C.), the 
antiferroelectric liquid crystal 60 softens, thereby flowing to close the 
opening of the liquid crystal inlet port 31. 
Thereafter, a leak valve 76 is opened and N.sub.2 gas is introduced in the 
chamber 71, so that the pressure in the chamber 71 is returned to an 
atmospheric pressure. Accordingly, a pressure difference between the 
inside and the outside of the liquid crystal cell is created, whereby the 
softened antiferroelectric liquid crystal 60 flows into the liquid crystal 
cell through the liquid crystal inlet port 31. 
In this case, as mentioned above, the opening width W1 of the liquid 
crystal inlet port 31 is larger than the width W2 of the effective display 
area R, and there is nothing to interrupt a flow of the antiferroelectric 
liquid crystal 60. Therefore, when the antiferroelectric liquid crystal 60 
is filled into the liquid crystal cell, the liquid crystal 60 is kept to 
flow uniformly and generally in parallel to the sides 32 and 33 of the 
seal 30 from the liquid crystal inlet port 31 to the rear side 34 of the 
seal 30 as indicated by arrows B in FIG. 5. 
Even when an filling speed of the liquid crystal 60 is not controlled, the 
speed of the flow of the liquid crystal 60 into the liquid crystal cell 
can be kept uniform. Therefore, the liquid crystal 60 is filled into the 
liquid crystal cell uniformly without any stagnation in the flow thereof. 
Consequently, a uniform orientation of molecules of the liquid crystal 60 
can be attained without leaving any filling marks in the liquid crystal 
cell, whereby an uneven display of the liquid crystal cell can be 
prevented. 
Further, as the flowing direction of the liquid crystal 60 corresponds to 
the rubbing direction of the alignment films 16 and 24, the uniform 
orientation of the liquid crystal 60 can be secured. Therefore, the liquid 
crystal cell can provide a high contrast display over the entire effective 
display area. 
Finally, in a sealing process S9, the liquid crystal inlet port 31 is 
sealed, and the entire manufacturing processes of the liquid crystal cell 
are completed. 
FIGS. 7 to 10 show a second embodiment of the present invention. 
In the second embodiment, as shown in FIG. 7, a process for forming a 
transparent electrode film and an insulating film on an opposite substrate 
S10, an alignment film formation process S11, a resist film formation 
process S12, and a rubbing treatment process S13 are adopted in place of 
the original opposite substrate formation process S2 and the spacers and 
fine-grained adhesives scattering process S4 in the first embodiment. 
In the process S10, transparent electrodes 22 consisting of a plurality of 
stripes and an insulating film 23 are deposited on a transparent glass 
substrate 21 in this order in the same manner as in the first embodiment. 
Thereafter, in the alignment film formation process S11, an alignment film 
24 is formed on the insulating film 23. 
In the next process, the resist film formation process S12, a photoresist 
film is deposited with a predetermined thickness on the alignment film 24 
(for example, 1.83 .mu.m) by a spin coat method. 
Next, an exposure treatment and a development treatment are performed on 
the photoresist film, whereby plural stripes of resist pillars 80 are 
formed. The pillars 80 stretch straight in parallel to sides 32 and 33 of 
a seal 30 (see FIGS. 8 and 9). A width of each one of the resist pillars 
80 is 50 .mu.m, and a pitch between the neighboring resist pillars 80 is 
400 .mu.m. 
Next, in the rubbing treatment process S13, a rubbing treatment is 
performed on the alignment film 24 so that a rubbing direction is opposite 
to a rubbing direction of an alignment film 16 in the same manner as 
mentioned in the first embodiment. In this case, the rubbing direction of 
the alignment film 24 is parallel to a longitudinal direction of the 
resist pillars 80. 
Through the processes S10 to S13, an original substrate 20A with the resist 
pillars 80 for use in the second embodiment is completed. 
Thereafter, in an overlapping process S5, the original substrate 20A is 
overlapped on the original substrate 10A with the seal 30, a dummy seal 40 
and the resist pillars 80 interposed therebetween. 
In a seal hardening process S6, thus overlapped original substrates 10A and 
20A are heated while a pressure or load is applied thereto, whereby the 
seal 30, the dummy seal 40, and resist pillars 80 are hardened. 
A gap between the substrates 10A and 20A can be kept appropriately not only 
by the dummy seal 40, but also by the resist pillars 80 which adhere to 
opposite surfaces of the original substrates 10A and 20A securely. 
Since a total area of the resist pillars 80 contacting and connecting two 
substrates 10A and 20A is larger than that of the fine grained adhesives 
in the first embodiment, a bonding strength between the original 
substrates 10A and 20A is greatly increased. Further, since each resist 
pillar 80 functions as a spacer, it is not necessary to use the spacers. 
Next, in a liquid crystal injection process S8, droplets of 
antiferroelectric liquid crystal 60 are placed dispersively on a color 
filter substrate 10 (see FIG. 10) in the same way as mentioned in the 
first embodiment. Thereafter, the liquid crystal 60 is filled into the 
liquid crystal cell through the liquid crystal inlet port 31 in the same 
way as mentioned in the first embodiment. The liquid crystal 60 flows 
smoothly into the liquid crystal cell along the resist pillars 80 through 
the liquid crystal inlet port 31, the width of which is larger than that 
of the effective display area. 
As a result, the liquid crystal is filled into the liquid crystal cell 
without any stagnation in a flow thereof and oriented uniformly. The other 
processes and effects are the same as those in the first embodiment. 
Next, a third embodiment will be described referring to FIGS. 11 and 12. 
In the third embodiment, when a seal 30 is printed in a seal printing 
process S3 as mentioned in the first embodiment, plural dam seals 31a are 
printed on the insulating film 15 in a liquid crystal inlet port 31. Each 
shape of dam seals 31a is an oblong ellipse with a longitudinal axis 
perpendicular to the liquid crystal filling flow, as shown in FIG. 11. 
Further, two lines of dam seals are printed with a staggered arrangement 
as shown in the drawing. In this embodiment, the liquid crystal inlet port 
31 with the plural dam seals 31a printed therein with the staggered 
arrangement is called hereafter a liquid crystal inlet port 35. The shape 
of dam seals 31a is not limited to the oblong ellipse, but may be changed 
to other shapes such as a streamlined shape or the like. 
The liquid crystal inlet port 35 is formed apart from the effective display 
area R with a predetermined space P (for example, 10 mm) on the left side 
of the effective display area R as shown in FIGS. 11 and 12. In this case, 
a cell gap (for example, 3.3 .mu.m) between an opposite substrate 20 and a 
color filter substrate 10 in the space P is larger than a cell gap (for 
example, 1.7 .mu.m) in the effective display area R by at least a 
thickness of color filters 12 as shown in FIG. 12. Since the dam seals 31a 
function as the dummy seal 40 in the first embodiment, the dummy seal 40 
is not used in this third embodiment. 
Thereafter, in a liquid crystal filling process S8, liquid crystal is 
filled into an empty liquid crystal cell gap through the liquid crystal 
inlet port 35 in the same way as mentioned in the first embodiment. 
The filling speed of the liquid crystal becomes fast proportionally to the 
size of the above mentioned cell gap. Since the size of the cell gap in 
the space P is larger than that in the effective display area R, the speed 
of the liquid crystal flowed passing through the cell gap in the effective 
display area R is slower than that in the space P. Consequently, 
turbulence in a flow of the liquid crystal created by the dam seals 31a is 
mitigated by a decrease of the flow speed of the liquid crystal in the 
area R, whereby the liquid crystal is filled into the cell gap smoothly 
and uniformly. 
Since the flow of the liquid crystal becomes uniform due to the gap size 
difference between in the space P and the area R, no filling marks are 
left and the flow direction matches to the rubbing direction of the 
alignment films 16 and 24, as well. As a result, a uniform orientation of 
the liquid crystal can be attained, whereby the same high contrast display 
can be realized over the effective display area R as in the first 
embodiment. Further, the strength of the liquid crystal cell can be 
improved by the dam seals 31a. 
Although in the third embodiment the cell gap in the space P is enlarged at 
least by the thickness of the color filters 12, the insulating film 15 and 
the protection film 13 may be removed by a photo-etching method or a 
partial polishing method so that the cell gap in the space P is further 
enlarged. 
Next, a fourth embodiment will be described referring to FIGS. 13 and 14. 
In the fourth embodiment, the liquid crystal inlet port 37 is adopted in 
place of the liquid crystal inlet port 35 in the third embodiment. 
In the liquid crystal inlet port 37, plural dam seals 37a are printed in an 
oblong elliptic shape with its longitudinal axis aligned in parallel to 
the liquid crystal flow, as shown in FIG. 13. 
Preferable dimensions measured after the dam seals are hardened are shown 
in FIG. 14. A width and a length of the sam seal 37a are 0.5 mm and 3 mm 
respectively, and a pitch between neighboring dam seals is 3 mm. Each of 
the dam seals 37a may be a streamlined shape directing to the flow of the 
liquid crystal. 
In the liquid crystal filling process S8, liquid crystal is filled into the 
liquid crystal cell through the liquid crystal inlet port 37 in the same 
manner as in the first, second and third embodiments. 
In this case, each dam seal 37a in the liquid crystal inlet port 37 is 
small in size and the longitudinal axis thereof is parallel to the flow 
direction of the liquid crystal, as shown in FIGS. 13 and 14. Therefore, 
turbulence in a flow of the liquid crystal passing through the liquid 
crystal inlet port 37 can be kept minimum. As a result, the liquid crystal 
flows uniformly and a uniform orientation thereof is attained. 
Next, a fifth embodiment will be described referring to FIGS. 15 and 16. 
In the fifth embodiment, plural stripes of resist pillars 90 are disposed 
on the alignment layer 24 of the substrate 20 in addition to the dam seals 
31a, substantially in the same way as mentioned in the second embodiment 
(see FIGS. 7 to 10). In other words, both features in the second and third 
embodiments are employed in this fifth embodiment. 
Accordingly, combined effects attained in the second and third embodiments 
can be attained in the fifth embodiment. 
Next, a sixth embodiment will be described referring to FIGS. 17 and 18. 
In the sixth embodiment, dam seals 36a at a liquid crystal inlet port 36 
are adopted in place of the dam seals 31a in the third embodiment. 
In the liquid crystal inlet port 36, plural dam seals 36a each having a 
small dot-like shape are printed in a staggered arrangement as shown in 
FIGS. 17 and 18. The sixth embodiment differs from the third embodiment 
only in the shape of the dam seals 36a. Preferable dimensions of the dam 
seals, measured after the dam seals are hardened, are shown in FIG. 18. A 
pitch between two rows of dam seals is 3 mm, a pitch between neighboring 
seals in a same row is also 3 mm, a diameter of the individual dam seal is 
0.25 mm, and a pitch between neighboring seals in different rows is 1.5 
mm. 
Liquid crystal is filled into the liquid crystal cell through the liquid 
crystal inlet port 36 in the same manner as in the foregoing embodiments. 
In this case, each dam seal 36a in the liquid crystal inlet port 36 has a 
small dot-like shape and two rows of the dam seals 36a are aligned in a 
staggered arrangement as shown in FIG. 18. Further, a space P between the 
liquid crystal inlet port 36 and the effective display area R is provided 
in this embodiment, too, as in the third embodiment. Therefore, turbulence 
in a flow of the liquid crystal is minimized due to synergistic effects of 
the above mentioned features. As a result, the flow of the liquid crystal 
becomes uniform and a direction of the flow corresponds to a rubbing 
direction, whereby the same effects as those in the third embodiment can 
be attained. 
FIGS. 19 and 20 show a seventh embodiment. 
In the seventh embodiment, plural stripes of resist pillars 100 are formed 
on the alignment layer 24 of the opposite substrate 20, which is the same 
as that in the sixth embodiment (see FIG. 17), substantially in the same 
way as mentioned in the second embodiment (see FIGS. 7 to 10). 
Each resist pillar 100 is faced to each dam seal 36a as shown in FIG. 19, 
so that the flow of the liquid crystal is not disturbed by the dam seals 
36a. The features other than the resist pillars 100 are the same as those 
in the sixth embodiment. 
Accordingly, the same effects as the resist pillars 80 in the second 
embodiment can realize can be attained by the resist pillars 100 in the 
seventh embodiment in addition to the effects mentioned in the sixth 
embodiment. 
Further, because of the above mentioned arrangement of the dam seals 36a 
and the resist pillars 100, even when turbulence such as stagnation occurs 
in a flow of the liquid crystal at a back side of each dam seal 36a (that 
is, between the dam seals 36a and the resist pillars 100), the turbulence 
is decreased by the end portion of the resist pillars 100 at the side of 
liquid crystal inlet port 36. Consequently, the flow of the liquid crystal 
into the effective display area becomes uniform. 
As a result, even when the turbulence in the flow of the liquid crystal 
occurs at the back side of the dam seals 36a, it does not result in 
irregularity of orientation of the liquid crystal in the effective display 
area. 
As a modification of the seventh embodiment, the dam seals 36a and the 
resist pillars 100 may be arranged as shown in FIG. 20. The dimensions of 
the preferable arrangement are shown in FIG. 20, but other selection are 
possible without departing from the gist of the present invention. 
In the present invention, the manufacturing processes of the liquid crystal 
cell in the first embodiment may be adopted to produce the liquid crystal 
cell in the fourth or sixth embodiment. In this case, although the space P 
mentioned in the fourth embodiment becomes narrower, each dam seal with a 
small dot-like shape or an oblong ellipse shape causes almost no 
disturbance in the flow of the liquid crystal when the liquid crystal is 
filled. Therefore, the same effects as those in the first embodiment can 
be realized in addition to the effect that the gap between the substrates 
is secured more firmly by the dam seals. 
In the foregoing embodiments, although the opening width W1 of the liquid 
crystal inlet port of the seal 30 is larger than the width W2 of the 
effective display area, this relationship may be modified. It is possible 
to make the opening width W1 of the liquid crystal inlet port of the seal 
30 smaller than the width W2 of the effective display area R in case the 
uniform flow of the liquid crystal is substantially attained. 
Further, in the present invention, after droplets of the liquid crystal are 
placed at the liquid crystal inlet port of the liquid crystal cell, the 
liquid crystal cell is disposed in the chamber 71 of the liquid crystal 
filling device 70. However, a separate liquid crystal supply device may be 
equipped in the chamber 71 so that the liquid crystal is supplied to the 
liquid crystal cell from the supply device before opening the leak valve 
76. 
Further, when the flowing direction of the liquid crystal is uniform, the 
flowing direction may deviate a little from the rubbing direction. This 
results in a little decrease of display contrast, but does not result in 
an irregular orientation of the liquid crystal. 
The liquid crystal is not limited to the antiferroelectric liquid crystal, 
but it may be ferroelectric liquid crystal, smectic liquid crystal, 
nematic liquid crystal or the like. This invention can be applied not only 
to a color liquid crystal display but also to a monochrome liquid crystal 
display. 
The dummy seal or dam seals may be formed apart from the seal 30 before the 
original substrates are overlapped. 
While the present invention has been shown and described with reference to 
the foregoing preferred embodiments, it will be apparent to those skilled 
in the art that changes in form and detail may be made therein without 
departing from the scope of the invention as defined in the appended 
claims.