JP2002341791A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi panel type display device with inconspicuous connection parts (joints) between respective display panels and with a wide viewing angle characteristic. SOLUTION: In the display device, a plurality of display panels 10 are connected with each other via the connection parts 22. Each of the plurality of the display panels 10 is provided with a display medium layer 16 and a translucent first substrate 14' disposed on the observer's side of the display medium layer 16. When the thickness of the first substrate 14' is represented by X, the width of each of non displaying regions 14c formed in mutually adjacent positions via the connection parts 22 of a plurality of the display panels 10 is represented by Y and the refractive index of the first substrate 14' is represented by n, an inequality Y>Xtan sin<-1> (1/n)} holds.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct-view type display device, and more particularly to a multi-panel type display device having a large screen by connecting a plurality of display panels on their side surfaces.

[0002]

2. Description of the Related Art In recent years, display devices used for audio visual (AV) devices and office automation (OA) devices have been reduced in weight, thickness, power consumption, definition, and display screen. (Hereinafter, referred to as a large screen) is required. Among them, a large screen is realized by a CRT (Cathode Ray Tube) system, a liquid crystal display (LCD), a plasma display (PDP), an electroluminescence (EL) display, a light emitting diode (LED) display. This is a problem common to various display devices.

In particular, liquid crystal display devices and EL display devices that perform active matrix driving take advantage of advantages such as full color display, excellent display quality, and a common manufacturing technique for active matrix substrates. It is being used in a wide range of fields, and expectations for a larger screen are high.

[0004] However, when the screen of a flat panel display device typified by an active matrix liquid crystal display device or an EL display device is enlarged, a defect caused by disconnection of a signal line or the like or a defective pixel in a manufacturing process. The rate rises sharply. In addition, the increase in screen size complicates the manufacturing process, resulting in a problem that the price of the display device increases.

In order to solve this problem, a display device having a large screen by connecting a plurality of display panels to each other on the same plane, or a pair of light-transmitting members constituting the large screen display panel is provided. A display device with a large screen is provided by using a substrate in which a plurality of small substrates are connected to each other on at least one of the substrates (sometimes referred to as a “connection substrate” and a substrate). Are known.

In such a large-screen display device using a large-screen method, there is a need for a technique for making connection portions between display panels adjacent to each other or between small substrates, that is, joints inconspicuous. For example, a multi-panel type liquid crystal display device with no noticeable seams is proposed in Japanese Patent Application Laid-Open No. 11-202308 by the present applicant.

[0007] Referring to FIG.
The structure and function of the liquid crystal display device disclosed in Japanese Patent Publication No. 308 will be described.

[0008] In the following, for the sake of simplicity, a display panel having a large screen by connecting (attaching) a plurality of display panels to each other is called a "large display panel". I will distinguish it from the panel. Note that the “large display panel” does not require a large display area. For example, a display panel having a size of less than 15 inches and including a plurality of display panels connected to each other is referred to as a “large display panel”. Also,
The “display panel” may be simply referred to as “panel”.

The large liquid crystal panel 700 of the liquid crystal display device disclosed in the above publication has a structure as shown in FIG.
It has a plurality of liquid crystal panels 70 and a connecting portion 82 for connecting the plurality of liquid crystal panels 70 to each other. Each liquid crystal panel 70 has a liquid crystal layer 76 between a pair of substrates 73 and 74.
have. The substrate 73 is, for example, a TFT substrate, and the substrate 74 is, for example, a color filter substrate. The color filter substrate 74 includes a color filter 74a and a light shielding portion 74b.
And a color filter layer containing 74c. The light-shielding portion 74c refers to a light-shielding portion (also referred to as a “connection-portion adjacent light-shielding portion”) arranged at a position adjacent to the connection portion 82, and the light-shielding portion 74b refers to another light-shielding portion. . The light shielding portions 74b and 74c may be collectively referred to as a black matrix (BM).

In the large liquid crystal panel 700, the substrate 7
Assuming that B is the thickness of 3 and 74, and A is the width of the adjacent light shielding portion 74c (the direction orthogonal to the extending direction of the connecting portion 82), | A |> Btan (sin ⁻¹ [1 / ｛(｛2 ) ・
n｝]). As a result, light transmitted through the connecting portion 82 does not reach the observer in a viewing range of 45 ° left and right with the connecting portion 82 as a center line of line symmetry from the normal direction of the display surface of the large liquid crystal panel 700. That is, the connection portion 82 is hard to be visually recognized by an observer, and the seam is inconspicuous.

The above publication discloses a large liquid crystal panel 70.
0, the width of the light-shielding portion 74b other than the light-shielding portion 74c of the display panel 70 is assumed to be Q, and the width of the connection portion 82 is assumed to be P, preferably satisfying the relationship of 2A + P = Q.

[0012]

However, the large-sized liquid crystal display device disclosed in the above publication is limited to a display device using a transmissive liquid crystal panel, and only 45 ° left and right viewing angle ranges are considered. Not.

[0013] Therefore, there is no condition for making the seams of a large liquid crystal panel using a transmissive liquid crystal panel having a viewing angle range of more than 45 ° inconspicuous. Furthermore, in a display device using a reflective display panel, a display device using a self-luminous display panel such as an EL display panel, and the like, conditions for making a seam difficult to see have not been studied. That is,
According to the technique disclosed in the above publication, the seams of the display panel having the wide viewing angle characteristics cannot be made inconspicuous.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a multi-panel display device having a wide viewing angle characteristic in which connection portions (seams) between display panels are inconspicuous. It is in.

[0015]

A display device according to the present invention is a display device in which a plurality of display panels are connected to each other via a connection portion, wherein each of the plurality of display panels includes a display medium layer, A first substrate having a light-transmitting property disposed on the viewer side of the display medium layer, wherein the thickness of the first substrate is X, and the first substrates are adjacent to each other via the connection portions of the plurality of display panels. When the width of each non-display area formed at the position is Y and the refractive index of the first substrate is n, Y>
Since the relationship of Xtan {sin ^-1 (1 / n)} holds, the above object is achieved.

Preferably, each of the plurality of display panels is a self-luminous display panel or a reflective display panel.

Each of the plurality of display panels further includes a second substrate disposed so as to face the first substrate via the display medium layer, and has a thickness Z of the second substrate.
May be larger than the thickness X of the first substrate.

[0018] The display panel is disposed on the viewer side of the plurality of display panels, and covers the entirety of the plurality of display panels and the connecting portion.
A third substrate having a light-transmitting property may be further provided.

The operation of the present invention will be described below.

In the display device according to the present invention, the thickness of the first substrate disposed on the observer side among the substrates of the display panel is X, and the first substrate is formed at a position adjacent to each other via the connection portion of the plurality of display panels. The width of each non-display area is Y,
Assuming that the refractive index of the substrate is n, Y> Xtan @ sin ^-1
Since the arrangement is such that the relationship of (1 / n)｝ is established, light passing through the connection portion is not emitted from the first substrate to the observer side. Therefore, the connecting portion is set as the center line of line symmetry from the normal direction of the display surface of the display panel, and
In the range of 0 °, that is, in the entire viewing angle range, the connection between the display panels becomes invisible to the observer, and the display quality is improved. However, if the display panel is a transmissive display panel,
The second substrate disposed so as to face the first substrate with the display medium layer (typically a liquid crystal layer) interposed therebetween also needs to satisfy the above relationship.

When a self-luminous display panel such as an EL panel or a reflective display panel is used as the display panel, only the first substrate needs to satisfy the above relationship. Therefore, the following advantages are obtained with respect to the configuration using the transmission type display panel.

In a configuration using a transmissive display panel,
When a display panel having a high aperture ratio and a high resolution is used, as the width of the non-display area (that is, the light-shielding portion) becomes narrower, both of the pair of substrates arranged on both sides of the display medium layer satisfy the above relationship so as to satisfy the above relationship. It is necessary to reduce the thickness of
There is a problem that the mechanical strength of the display panel is reduced, the handling property in the manufacturing process of the display device is reduced, and the yield is reduced. On the other hand, in a configuration using a self-luminous or reflective display panel, only the first substrate satisfies the above relationship, and the thickness of the second substrate can be made sufficiently large. That is, by using the second substrate thicker than the thickness of the first substrate, the mechanical strength of the display panel can be ensured.

Further, a third substrate having a light-transmitting property, which is disposed on the viewer side of the plurality of display panels and covers the entirety of the plurality of display panels and the connection portion, is further provided, so that the external light on the display surface can be obtained. The reflection (surface reflection) can be made uniform, and the display quality can be further improved. That is, the degree of surface reflection of external light (intensity is determined by the angle distribution) due to the difference between the surface condition of the display panel and the surface condition of the connection portion, and the difference in the refractive index between the substrate material of the display panel and the material forming the connection portion. ), The uniformity of surface reflection of external light may be impaired and the connection portion may be noticeable. However, by providing the third substrate covering the connection portion, the connection portion is prevented from being noticeable due to the difference in surface reflection. can do.

Further, also in the display device of the present invention, the total width of the connection portion and the light shielding portions located on both sides thereof is substantially equal to the width of the other light shielding portions (2 in the large liquid crystal panel 700).
(A + P = Q).

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure and function of a display device according to an embodiment of the present invention will be described below with reference to the drawings, but the present invention is not limited to the following example.

(Embodiment 1) The structure and function of a liquid crystal display device of Embodiment 1 will be described with reference to FIGS. 1 and 2 are schematic cross-sectional views of a large-sized liquid crystal panel 100 included in the liquid crystal display device according to the first embodiment. FIG.
5 is an enlarged view of a portion including a connection portion 22 of the large-sized liquid crystal panel 100. FIG.

As shown in FIG. 1, the large liquid crystal panel 10
0 has a plurality of liquid crystal panels 10 connected to each other by a connection portion 22. In the following, for the sake of simplicity, a case where two liquid crystal panels 10 arranged on the left and right are connected to each other on their side surfaces will be exemplified. For example, in an active matrix type liquid crystal display device, the connection unit 22 is formed parallel to a row or a column (parallel to a scanning line or a signal line).

Each liquid crystal panel 10 has a liquid crystal layer 16 between a pair of substrates 13 and 14. The pair of substrates 13 and 14 are adhered to each other with a sealing material 17. Here, the substrate 13 is an active matrix substrate, and the substrate 14 is a color filter substrate.

The active matrix substrate 13 is a substrate 1
3 ', a pixel electrode 15 formed on the surface of the substrate 13' on the liquid crystal layer 16 side, an active element, a scanning line, a signal line (all not shown), and the like. As the active element, a metal insulator (MIM) is used.
r Metal), a TFT (thin film transistor), or the like can be used. The substrate 13 'is typically a glass substrate, but a plastic substrate may be used.
When the liquid crystal panel 10 is a reflective liquid crystal panel, a substrate disposed on the side opposite to the viewer with respect to the liquid crystal layer 16 does not need to have a light-transmitting property, and thus a semiconductor substrate can be used as the substrate 13 '.

The color filter substrate 14 is a transparent substrate 1
4 ′, a color filter 14a and light shielding portions 14b and 14b formed on the surface of the transparent substrate 14 ′ on the liquid crystal layer 16 side.
and a color filter layer containing c. Light shielding part 14c
Indicates a light-shielding portion arranged at a position adjacent to the connection portion 22, and the light-shielding portion 14b indicates another light-shielding portion. That is, the light shielding portion 14b indicates a light shielding portion provided between picture elements arranged in a matrix. The light shielding portions 14b and 14c are generally formed integrally, and the light shielding portions 14b and 14c may be collectively called a BM.

The color filter substrate 14 further has a counter electrode (not shown) on the surface on the liquid crystal layer 16 side. A voltage is applied to the liquid crystal layer 16 by the pixel electrode 15 of the active matrix substrate 13 and a counter electrode (not shown) at a position facing the pixel electrode 15. Among the regions to which the voltage is applied by the pixel electrode 15 and the opposing electrode (not shown) at the position opposing the pixel electrode 15, the region where the color filter 14a is formed (the region where the light shielding portions 14b and 14c are not formed) is a picture. Element (sometimes called an “opening”).

The liquid crystal panel 10 used for the large-sized liquid crystal panel 100 is not limited to the above-mentioned configuration, and various known liquid crystal panels can be used. The active matrix substrate 13 and the counter substrate 14 may be arranged in reverse, or an IPS (In-Plane-Switch) in which an electrode for applying a voltage to the liquid crystal layer 16 is formed on one of the substrates.
ing) mode liquid crystal panel. further,
The invention is not limited to the active drive type liquid crystal panel, and a passive drive type liquid crystal panel can be used. Further, the color filter 14a may be omitted.

However, it is preferable to use a reflective liquid crystal panel as the liquid crystal panel 10 as described later.
As the reflective liquid crystal panel, various known liquid crystal panels can be used. For example, the pixel electrode 15 may be formed using a metal material having excellent reflection characteristics, or the liquid crystal layer 1 may be formed.
A cholesteric liquid crystal material may be used as the material of No. 6, and the selective reflection function of the cholesteric layer may be used. Of course, depending on the display mode of the liquid crystal panel 10, a polarizing plate or a retardation plate may be provided, or an alignment film may be provided on the surfaces of the substrates 13 and 14 on the liquid crystal layer 16 side.

The connecting portion 22 connecting the two liquid crystal panels 10 to each other is formed of, for example, an adhesive. The refractive index of the material forming the connection portion 22 is preferably substantially equal to the refractive index of the transparent substrate 14 'forming the active matrix substrate 14, but may be different. As the transparent substrate 14 ', for example, a glass substrate or a plastic substrate is used. In addition, a film can be used without being limited to a plate. Further, the material forming the connection part 22 is as follows.
For example, it is an adhesive, and an epoxy-based or acrylic-based adhesive (thermosetting or photocuring) can be used.

The large liquid crystal panel 100 is configured so that light emitted from the picture element (color filter 14a) and passing through the connection portion 22 is not emitted from the counter substrate 14 to the observer side. That is, the configuration is such that light that has passed through the picture element does not reach the connection section 22.

Specifically, the width of the light-shielding portion adjacent to the connection portion is represented by Y,
Assuming that the thickness of the transparent substrate 14 'constituting the counter substrate 14 is X and the refractive index of the transparent substrate 14' is n, the following relational expression (1)
Holds. Y> Xtan {sin ^-1 (1 / n)} (1)

When the above-mentioned relational expression (1) is satisfied, the connection part 22 is not recognized even if the connection part 22 between the liquid crystal display panels 10 is observed from any angle of ± 90 ° on the left and right.

Referring to FIG. 2, the above relational expression (1)
Will be described more specifically. As shown in FIG. 2, the display light reflected by the picture element electrode 15 is
After transmitting through the transparent substrate 14 ′ at the transmission angle θ ₂ , the emission angle θ ₁
Out of the counter substrate 14. At this time, the following relational expression (2) is established between the emission angle θ ₁ and the transmission angle θ ₂ according to Snell's law. However, the medium around the transparent substrate 14 'is air (refractive index is 1). sin θ ₁ = nsin θ ₂ (2)

Here, the critical angle θ ₂ ′ of the transmission angle required to make the left and right viewing angles of the large liquid crystal panel 100 ± 90 ° is θ ₂ ′ = sin ⁻¹ (1 / n). Becomes

On the other hand, when observing the large liquid crystal panel 100 from an oblique direction, in order to make the connection portion 22 (seam) inconspicuous, light passing through the picture element may be prevented from reaching the connection portion 22. For this purpose, as is clear from FIG. 2, the thickness X of the transparent substrate 14 'and the width Y of the light-shielding portion 14c adjacent to the connection portion may satisfy the following relational expression (3). Y / X> tan θ ₂ ′ (3)

When calculating the relational expression (3), the thickness of the liquid crystal layer 16 and the thickness of the color filter layer and the BM formed on the transparent substrate 14 'are smaller than those of the above X and Y. Since these values are smaller by one digit or more, they can be ignored with good approximation.

In the large-sized liquid crystal panel 100 included in the display device according to the present embodiment, the structure near the connecting portion 22 between the liquid crystal display panels 10 adjacent to each other is determined by the relations derived from the above-mentioned relational expressions (2) and (3). Since the expression (1) is satisfied, the light transmitted through the connecting portion 22 does not reach the observer, and the connecting portion 22 is not affected by viewing the large liquid crystal panel 100 from any viewing angle of ± 90 ° left and right. It will not be recognized.

For example, a transparent substrate 14 '(opposite substrate 14)
Is 0.2 mm (200 μm) and the refractive index is n = 1.53, the width Y of the light-shielding portion 14c adjacent to the connecting portion must be equal to 0.1 to satisfy the above relational expression (1). 173
mm or more.

In the above relational expression (1), the upper limit of the width Y of the light-shielding portion 14c adjacent to the connection portion is not particularly limited. However, on the display screen of the large-sized liquid crystal panel 100, the distance (pixel pitch) between picture elements adjacent to each other via the connection part 22 is different from that of the individual liquid crystal panel 10.
Is not substantially the same as the pixel pitch in
(Seams) will be noticeable. Accordingly, in the connection portion 22, the sum of the width Y of the two light-shielding portions 14c adjacent to the left and right connection portions and the gap (P in FIG. 1) between the connection portions 22 is equal to the width of the light-shielding portion 14b in other regions (in FIG. It is preferable that Q) is substantially the same as Q). Specifically, assuming that the width of the light shielding region in the display panel extending in parallel with the connection portion is R and the width of the connection portion is Q, it is preferable that the relationship 0.8Q ≦ 2Y + P ≦ 1.2Q be satisfied. More preferably, the relationship of 0.9Q ≦ 2Y + P ≦ 1.1Q is satisfied.

In this embodiment, a thin glass substrate having a thickness X of 0.2 mm is used as the transparent substrate 14 ′ of the opposing substrate 14. , A 0.7 mm thick substrate (eg, a glass substrate) is used. This is possible because the liquid crystal display device of the present embodiment employs a reflection mode using external light as a display method. Generally, in the case of a transmissive display device having a backlight on the back side of a display panel, display light passes through both the active matrix substrate 13 and the corresponding substrate 14 before reaching the viewer. For this reason, in order to make the connection portion 22 (seam) inconspicuous, the thickness Z of the active matrix substrate 13 (transparent substrate 13 ′) is not limited to the thickness of the opposite substrate (transparent substrate 13 ′).
And the thickness of the active matrix substrate (second substrate) 13 cannot be increased. Therefore, taking the above case as an example, it is necessary to set both X and Y to 0.2 mm, which causes a problem of lowering the mechanical strength of the display panel. However, in the case of a transmissive type, a transflective type, or a transmissive / reflective type (in which a transmissive area and a reflective area are provided in each picture element area), a plurality of active matrix substrates 13 and their connection portions 22 are provided. If a support substrate is separately provided on the back side of the active matrix substrate 13 so as to cover the entirety of the substrate, mechanical strength can be ensured.

When a reflection mode using external light is adopted as the display system, the display light is not affected by the active matrix substrate 13 on the back side of the liquid crystal layer 16 or the connection portion 22 thereof.
The thickness Z of the (substrate 13 ') is not restricted at all. Therefore, the active matrix substrate 13 (substrate 1)
The thickness Z of 3 ′) can be set larger than X. For example, for X = 0.2m, Z = 0.7mm, Z
= 1.1 mm. As a result, the connection 2
The large liquid crystal panel 100 can be configured using the liquid crystal panel 10 having sufficient mechanical strength while satisfying the relational expression (1) so that 2 is inconspicuous.

By the way, the thickness X of the transparent substrate 14 ′ constituting the opposing substrate 14 of the liquid crystal panel 10 of the present embodiment is set to 0.
Although the thickness is set to 2 mm, such a thin substrate is difficult to handle in the manufacturing process of the liquid crystal display panel 10 because handling becomes difficult. Therefore, the liquid crystal panel 10 is formed by using the active matrix substrate 13 and the opposing substrate 14 having a thick substrate (for example, a glass substrate having a thickness of 0.7 mm).
Then, only the transparent substrate 14 ′ of the opposing substrate 14 is processed to be thin by etching or polishing, whereby the liquid crystal panel 10 having the opposing substrate 14 thin can be easily produced. For example, when the transparent substrate 14 'is a glass substrate,
The thickness of the transparent substrate 14 'is reduced by, for example, etching the outer surface of the transparent substrate 14' using a hydrofluoric acid-based etchant containing sulfuric acid.

The material of the transparent substrate 14 'is not limited to glass, but may be plastic. When the resolution of the large liquid crystal panel 100 is high and the width X of the light-shielding portion 14b adjacent to the connection portion cannot be made large, for example, the transparent substrate 1
When a small value of about 10 to 200 μm is required as the thickness X of 4 ′, it is convenient to use a plastic film as the transparent substrate 14 ′.

As described above, in the liquid crystal display device of the present embodiment, the above-mentioned relational expression (1) is satisfied at the connection portion 22 between the plurality of liquid crystal display panels 10. As a result, the light transmitted through the connection portion 22 does not reach the observer, and the seam is inconspicuous. Even if a liquid crystal panel having a wide viewing angle characteristic (for example, a right and left viewing angle of 90 °) is used as the liquid crystal panel 10, a seam is not visually recognized, and a wide viewing angle large screen display device with high display quality is realized. be able to.

Further, when a liquid crystal panel of a reflection mode is used as the liquid crystal panel 10, the thickness and connection form (for example, the color, material, and connection portion of the adhesive) of the active matrix substrate 13 disposed on the back side of the liquid crystal layer 16 are determined. ), And a thick substrate can be used as the active matrix substrate 13. For example, a fitting structure may be provided on the side surface of the active matrix substrate 13 or chamfering may be performed. As a result, a highly reliable display device can be obtained without sacrificing the mechanical strength of the liquid crystal panel 10.

Further, as shown in FIG. 3, a light-transmitting substrate 32 may be provided on the surface of the large liquid crystal panel 100 on the observer side.

The large liquid crystal panel 200 shown in FIG. 3 has a plurality of liquid crystal panels 1 on the viewer side of the counter substrate 14 arranged on the viewer side of the large liquid crystal panel 100 shown in FIG.
0 and a light-transmitting substrate 32 arranged so as to cover the entirety of the connection portion 22.

Since the large-sized liquid crystal panel 100 satisfies the relation of the relational expression (1) as described above, the display light passing through the connection section 22 is not recognized by the observer at all, and
Is not noticeable. However, on the observer side surface of the large display panel 100, the difference between the surface state of the liquid crystal panel 10 and the surface state of the connection portion 22, and the difference in the refractive index between the transparent substrate 14 'and the material forming the connection portion 22 are different. Depending on
If the degree of surface reflection of external light (intensity is angular distribution) is different,
In some cases, the uniformity of surface reflection of external light is impaired, and the connection portion 22 is conspicuous. On the other hand, by providing the translucent substrate 32 that covers the plurality of liquid crystal panels 10 and the connection portions 22 like the large liquid crystal panel 200, the connection portions 22 can be prevented from being conspicuous due to a difference in surface reflection. it can.

As the translucent substrate 32, a transparent substrate such as a glass substrate or a plastic substrate can be used.
When a polarizing plate, a retardation plate or a diffusion plate is provided on the viewer side of the transparent substrate 14 'according to the display mode, the light-transmitting substrate 32 may be used as these. In addition,
The adhesive layer 22a for fixing the translucent substrate 32 to the surface of the large-sized liquid crystal panel 100 can be formed of, for example, a transparent adhesive like the connecting portion 22. Adhesive layer 22a and connection part 2
2 can be collectively formed in the same process using the same adhesive.

(Embodiment 2) The structure and function of an EL display device of Embodiment 2 will be described with reference to FIG. FIG. 4 shows a large EL panel 40 included in the EL display device according to the second embodiment.
0 shows a schematic sectional view.

As shown in FIG. 4, the large EL panel 40
0 has a plurality of EL panels 40 connected to each other by a connection section 52. Hereinafter, for the sake of simplicity, a case where two EL panels 40 arranged on the left and right are connected to each other on their side surfaces will be exemplified. For example, in an active matrix type EL display device, the connection section 52 is formed parallel to a row or a column (parallel to a scanning line or a signal line).

Each EL panel 40 has an EL layer 46 between a pair of substrates 43 and 44. The pair of substrates 43 and 44 are adhered to each other by the sealant 4, and the EL layer 46 is protected from the outside (moisture and / or impurities in the air). Here, the substrate 43 is an active matrix substrate, and the substrate 44 is a counter substrate.

The active matrix substrate 43 is a substrate 4
3 ′, a picture element electrode (for example, a cathode) 45 formed on the surface of the substrate 43 ′ on the EL layer 46 side, an active element,
It has scanning lines and signal lines (both not shown).
As the active element, a TFT (thin film transistor) or the like can be used. The substrate 43 'is typically a glass substrate, but a plastic substrate may be used. Since the substrate disposed on the side opposite to the viewer of the EL panel 40 does not need to have a light-transmitting property, a semiconductor substrate can be used as the substrate 43 '.

The counter substrate 44 has a transparent substrate 44 'and a counter electrode (for example, an anode) 44a formed on the surface of the transparent substrate 44' on the EL layer 46 side. Counter electrode 44a
Are formed so as to face the pixel electrodes 45 with the EL layer 46 interposed therebetween, and the EL layer 46 formed for each pixel is formed.
Voltage. Counter electrode 44a and picture element electrode 45
The area where is formed corresponds to the picture element, and the other areas are non-display areas that do not contribute to display. here,
A non-display area formed between the picture elements arranged in a matrix is referred to as a non-display area 44b, and a non-display area arranged at a position adjacent to the connection section 22 is referred to as a non-display area (“non-display area adjacent to connection section”). . "44c). When a color filter or a light-blocking portion (BM) is formed for the purpose of improving color purity, etc., the liquid crystal panel 10 (FIG.
), The color filter corresponds to the picture element (display area), and the light-shielding portion corresponds to the non-display area.

The EL panel 40 used for the large-sized EL panel 400 is not limited to the above-described configuration, and various known EL panels can be used. The active matrix substrate 43 and the counter substrate 44 may be arranged in reverse, or a passive drive type EL panel may be used. Further, as a material forming the EL layer 46, various known EL materials can be used. For example, the organic E disclosed in JP-A-2000-173770 is disclosed.
L material can be used.

The large EL panel 400 is composed of a picture element (the EL layer 4).
The configuration is such that light emitted from 6) and passing through the connection portion 52 is not emitted from the counter substrate 44 to the observer side. That is, the light that has passed through the picture element is
Is configured not to reach.

Specifically, the thickness of the transparent substrate 44 ′ constituting the counter substrate 44 is X, the refractive index of the transparent substrate 44 ′ is n,
Assuming that the width of the connection portion adjacent non-display area 44c is Y, the relational expression (1) is satisfied as in the case of the large liquid crystal panel 100 of the first embodiment, and the connection portion 52 is emitted from the EL layer 46. , But is not emitted from the counter substrate 44 to the observer side. As a result, large E
Even if the L panel 400 is viewed from any viewing angle of ± 90 ° left and right, the connection portion 52 is not recognized, and light emitted in all directions from the EL layer 46 can be effectively used for display.

In the above relational expression (1), the upper limit of the width Y of the non-display area 14c adjacent to the connection portion is not particularly limited. However, large EL panels 40
0 on the display screen 0, the interval between the picture elements adjacent to each other via the connection section 52 (picture element pitch) is not substantially the same as the picture element pitch in each EL panel 40.
2 (seam) will be noticeable. Therefore, the connecting portion 52
, The sum of the width Y of the two non-display areas 44c adjacent to the left and right connection parts and the gap (P in FIG. 4) between the connection parts 52 is the width of the non-display area 44b in other areas (Q in FIG. 4). Is preferably substantially the same as Specifically, assuming that the width of the light-shielding region in the display panel extending in parallel with the connection portion is R and the width of the connection portion is Q, it is preferable that the relationship 0.8Q ≦ 2Y + P ≦ 1.2Q be satisfied. 0.9Q ≦ 2Y + P ≦
More preferably, the relationship of 1.1Q is satisfied.

The EL panel 40 is a self-luminous display panel.
The active matrix substrate 43 on the back side of the layer 46 and the connection portion 52 are not affected, and the thickness Z of the active matrix substrate 43 (substrate 43 ′) is not restricted at all. Therefore, the thickness Z of the active matrix substrate 43 (substrate 43 ′) can be set to be larger than X. For example, for X = 0.2 m, Z =
It can be set to 0.7 mm or Z = 1.1 mm. As a result, it is possible to configure the large-sized EL panel 400 using the EL panel 40 having sufficient mechanical strength while satisfying the relational expression (1) so that the connection portion 52 is inconspicuous.

As described above, in the EL display device of the present embodiment, the above-mentioned relational expression (1) is satisfied at the connection portion 52 between the plurality of EL display panels 40. As a result, the light transmitted through the connection portion 52 does not reach the observer, and the seam is inconspicuous. That is, it is possible to realize a high-quality large-screen display device with high light use efficiency without impairing the wide viewing angle characteristics of the EL panel 40.

Further, the active matrix substrate 43 disposed on the back side of the EL layer 46 has a high degree of freedom in thickness and connection form, and a thick substrate can be used as the active matrix substrate 43. As a result, a highly reliable display device can be obtained without sacrificing the mechanical strength of the EL panel 40.

Further, as shown in FIG.
A substrate 62 having a light-transmitting property may be provided on the surface of the L panel 400 on the observer side.

The large EL panel 500 shown in FIG. 5 has a plurality of EL panels 4 on the viewer side of the counter substrate 44 arranged on the viewer side of the large EL panel 400 shown in FIG.
0 and a light-transmitting substrate 62 arranged so as to cover the entirety of the connection portion 52.

By providing the light-transmitting substrate 62 on the observer-side surface of the large-sized EL panel 400 as described above, the surface reflection of external light can be prevented as described above with reference to FIG. Due to the uniformity, the connection portion 52 can be prevented from being noticeable.

As the translucent substrate 62, a transparent substrate such as a glass substrate or a plastic substrate can be used.
The adhesive layer 62a for fixing the translucent substrate 62 to the surface of the large-sized EL panel 400 can be formed of, for example, a transparent adhesive like the connection portion 62. Adhesive layer 62a and connection part 5
2 can be collectively formed in the same process using the same adhesive.

Further, the large EL panel 50 shown in FIG.
As shown in FIG.
May be provided. By providing the substrate 64, the EL
The layer 46 can be more reliably protected from the outside. In particular, since the characteristics of the organic EL material are likely to deteriorate when exposed to moisture or impurities in the air, it is preferable to provide the substrate 64.

By arranging the sealing material 47 on the edge of each EL panel 40 and filling the bonding portion 52 between the EL panels 40 with an adhesive (resin), the organic EL material can be isolated from the outside air. Although possible, it is difficult to completely isolate the resin material because it has the property of slightly transmitting gas. On the other hand, by adopting a structure in which the connection portion 52 of the display panel 40 is sandwiched between the front substrate 62 and the rear substrate 64, it is possible to more reliably shut off from the outside air. In particular, when the front substrate 62 and the rear substrate 64 are made of an inorganic material having excellent gas barrier properties, the organic EL material can be almost completely isolated from the outside air, and the reliability is improved. A glass plate is suitable for the front substrate 62 because light transmission is also required, and a glass plate or a metal plate can be used for the back substrate 64. Back substrate 64 is large EL panel 4
The adhesive layer 62b for fixing to the back surface of the sheet No. 00 may be formed of an adhesive.

In the first and second embodiments, FIG.
Although the display device 600A in which two display panels 60A are connected to each other as shown in FIG. 6A has been described as an example, the present invention is not limited to this.
Display device 600 in which two display panels 60B are connected to each other
B or three or more display panels 6 as shown in FIG.
Display device 600 in which OCs are continuously connected in one direction
It goes without saying that C can be configured.

The display panel is not limited to the exemplified liquid crystal panel and EL panel, but may be an electrophoretic display panel,
Any display panel such as an ED display panel that performs reflective display or self-luminous display can be used for the display device of the present invention.

[0075]

According to the present invention, there is provided a multi-panel display device having a wide viewing angle characteristic in which connection portions (seams) between display panels are inconspicuous. In addition, when a reflective or self-luminous display panel is used as the display panel, the thickness of the rear substrate can be made sufficiently large, so that a large-sized display panel having high mechanical strength and excellent reliability can be relatively easily manufactured. It can be realized with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a large-sized liquid crystal panel 100 included in a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged view of the vicinity of a connection portion 22 of the large-sized liquid crystal panel 100.

FIG. 3 is a schematic cross-sectional view of a large-sized liquid crystal panel 200 included in another liquid crystal display device according to the first embodiment of the present invention.

FIG. 4 is a schematic cross-sectional view of a large-sized EL panel 400 included in an EL display device according to a second embodiment of the present invention.

FIG. 5 is a schematic cross-sectional view of a large-sized EL panel provided in another EL display device according to a second embodiment of the present invention.

FIGS. 6A to 6C are plan views showing examples of arrangement of a display panel of a display device according to the present invention.

FIG. 7 is a schematic sectional view of a conventional large liquid crystal panel 700.

[Explanation of symbols]

 Reference Signs List 10 liquid crystal panel 13 active matrix substrate 13 'substrate 14 color filter substrate 14' transparent substrate 14a color filter 14b light shielding portion 14c formed between picture elements 14c light shielding portion formed adjacent to connection portion 15 pixel electrode 16 Liquid crystal layer 17 Sealing material 22 Connection part 100, 200 Large liquid crystal panel

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09F 9/35 G09F 9/35 (72) Inventor Kenichi Ishiguro 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka 2H089 HA33 HA40 KA11 KA15 QA05 QA10 QA11 SA18 TA06 5C094 AA01 AA14 BA03 BA27 BA43 CA19 DA01 HA08 5G435 AA01 BB04 BB05 BB12 BB15 CC09 KK02

Claims (4)

[Claims] 1. A display device in which a plurality of display panels are connected to each other via a connection unit, wherein each of the plurality of display panels is disposed on a display medium layer and on an observer side of the display medium layer. And a first substrate having a light-transmitting property, wherein the thickness of the first substrate is X, and the thickness of each of the non-display areas formed at positions adjacent to each other via the connection portions of the plurality of display panels. A display device in which a relationship of Y> Xtan {sin ⁻¹ (1 / n)} is satisfied, where Y is a width and n is a refractive index of the first substrate. 2. The display device according to claim 1, wherein each of the plurality of display panels is a self-luminous display panel or a reflective display panel. 3. Each of the plurality of display panels further includes a second substrate disposed to face the first substrate with the display medium layer interposed therebetween, and the second substrate has a thickness Z. The display device according to claim 2, wherein the thickness is larger than the thickness X of the first substrate. 4. A light-transmitting third substrate, which is disposed on the viewer side of the plurality of display panels and covers the entirety of the plurality of display panels and the connection unit.
4. The display device according to any one of items 1 to 3.