Optical: systems and elements – Absorption filter
Reexamination Certificate
2002-07-12
2004-08-31
Chang, Audrey (Department: 2872)
Optical: systems and elements
Absorption filter
C349S104000, C349S106000, C349S107000
Reexamination Certificate
active
06785068
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a color filter substrate and an Electro-optical device, and a manufacturing method for a color filter substrate and a manufacturing method for an Electro-optical device, and particularly relates to a structure of a color filter suitably used with a transflective Electro-optical device.
2. Background Art
Conventionally, transflective liquid crystal display panels enabling visualization of both reflective display using external light and transmissive display using illumination light from a back-light or the like, have been known. Such transflective liquid crystal display panels comprise a reflective layer for reflecting external light into the panel, and are configured so that illumination light from a back-light or the like can transmit through the reflective layer. As for this type of reflective layer, there are those having patterns with openings (slits) at a predetermined ratio for each pixel of the liquid crystal display panel.
FIG. 18
is a schematic cross sectional diagram illustrating the schematic configuration of a conventional transflective liquid crystal display panel
100
in model fashion. This liquid crystal display panel
100
has a configuration wherein a substrate
101
and a substrate
102
are adhered one to another by a seal material
103
, with liquid crystal
104
being sealed in between the substrate
101
and the substrate
102
.
A reflective layer
111
having openings
111
a
for each pixel is formed on the inner face of the substrate
101
, and a color filter
112
having colored layers
112
r
,
112
g
, and
112
b
, and a protective layer
112
p
, are formed on this reflective layer
111
. Transparent electrodes
113
are formed on the surface of the protective layer
112
p
of the color filter
112
.
On the other hand, a transparent electrodes
121
are formed on the inner face of the substrate
102
, so as to intersect with the transparent electrodes
113
on the opposing substrate
101
. Now, alignment film, hard transmissive film, etc., is formed on the transparent electrodes
113
on the substrate
101
and the transparent electrodes
121
on the substrate
102
as necessary.
Also, a phase difference plate (¼ wavelength plate)
105
and polarizing plate
106
are sequentially disposed out-of-plane on the substrate
102
, and a phase difference plate (¼ wavelength plate)
107
and polarizing plate
108
are sequentially disposed out-of-plane on the substrate
101
.
The liquid crystal display panel
100
configured thus is attached in the state of a back-light
109
disposed at the rear side thereof in the event of being installed in electronic equipment such as cellular telephones, portable information terminals, and the like. With this liquid crystal display panel
100
, external light is transmitted through the liquid crystal
104
following the reflection path R in daytime or in bright places such as indoors and is reflected on the reflective layer
111
, and transmits through the liquid crystal
104
again and is discharged, so reflective display is visually recognized. On the other hand, the back-light
109
is lit at nighttime or dark places such as outdoors, whereby the illumination light of the back-light
109
which has transmitted through the openings
111
a
is transmitted through the liquid crystal display panel
100
following the transmission path T and is discharged, so transmissive display is visually recognized.
SUMMARY OF THE INVENTION
However, with the above-described conventional transflective liquid crystal display panel
100
, the light passes through the color filter
112
twice, coming and going, with the reflection path R, while the light only passes through the color filter
112
once with the transmissive path T, so there is the problem that the saturation deteriorates for transmissive display as compared to the saturation for reflective display. That is to say, with reflective display, the brightness of the display generally tends to be insufficient, so there is the need to set the light transmissivity of the color filter
112
high to secure brightness for the display, but this means that sufficient saturation cannot be obtained for transmissive display.
Also, the number of times of light passing through the color filter differs between reflective display and transmissive display as mentioned above, so the color of the reflective display and the color of the transmissive display greatly differ, and accordingly there is the problem that this presents an uncomfortable sensation.
Accordingly, the present invention has been made to solve the above problems, and it is an object thereof to provide a color filter substrate capable of securing both brightness for reflective display and saturation for transmissive display in the event of application to a display device capable of both reflective display and transmissive display. It is also to provide a transflective Electro-optical device capable of securing both brightness for reflective display and saturation for transmissive display. It is also an object to realize display technology capable of reducing difference of saturation between reflective display and transmissive display.
In order to solve the above problems, a color filter substrate according to the present invention comprises: a substrate; a colored layer disposed on the substrate, and having a light color portion, and a deep color portion with higher light density than the light color portion; and a reflective layer, disposed on the substrate, and having a transmitting portion essentially capable of transmitting light; wherein the deep color portion is disposed so as to overlay at least the transmitting portion in planar fashion.
According to the present invention, due to a colored layer having a light color portion and deep color portion being provided, and the deep color portion being disposed so as to overlay at least the transmitting portion in planar fashion, light passing through the transmitting portion of the reflective layer passes through the deep color portion, so the saturation of transmitted light can be improved over the conventional.
Now, light density means the capabilities per unit thickness of the colored layer for causing deviation of the wavelength distribution of light, wherein, in the event that the light density is high (great) the color (colorfulness) of the transmitted light is intense, and n the event that the light density is low (small), the color of the transmitted light is weak. In the event that the colored layer contains coloring material such as pigment or dye of the like, this light density normally has a positive correlation with the amount of the coloring material.
As for specific parameters having correlation with the concept of color density, for example, the Y value in an XYZ color system corresponding to visually perceived transmissivity or brightness or the L* value in a Lab color system, i.e., the integrated value of spectral transmissivity in the visual light range (e.g., the wavelength range of 380 nm to 780 nm), can be used. The Y value and L* value have a negative correlation with color density (e.g., an inversely proportionate relation). Accordingly, the Y value or L* value in the deep color portion will be smaller than the Y value or L* value in the light color portion.
As for specific parameters having correlation with the concept of color density, the area of polygons configured of points corresponding to the hue of the colored layer on a chromaticity diagram may be used. The area of polygons has a positive correlation with color density (e.g., a proportionate relation). Accordingly, the area of a polygon configured of points corresponding to the hue of a deep color portion on a CIE (1931) color system xy chromaticity diagram or a CIE (1976) color system a*b* chromaticity diagram, for example, is greater than a polygon configured of points corresponding to the hue of a light color portion on the same chromaticity diagram. Note that in the event of having a tri-color colo
Otagiri Yoshihiro
Takizawa Keiji
Chang Audrey
Harness & Dickey & Pierce P.L.C.
Seiko Epson Corporation
LandOfFree
Color filter substrate and electro-optical device,... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Color filter substrate and electro-optical device,..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Color filter substrate and electro-optical device,... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3357574