WO2012144179A1

WO2012144179A1 - Liquid crystal display device

Info

Publication number: WO2012144179A1
Application number: PCT/JP2012/002585
Authority: WO
Inventors: 壮史石田; 一弥甲斐田; 真也門脇; 博敏安永
Original assignee: シャープ株式会社
Priority date: 2011-04-20
Filing date: 2012-04-13
Publication date: 2012-10-26

Abstract

A liquid crystal display device (1) is provided with: a liquid crystal display panel (50a), which has a liquid crystal layer (40), and has red, green and blue sub-pixels arranged therein; a backlight (70), which emits blue light (Lb); a first polarization plate (51a), which is provided on the facing substrate (30) side, which is the reverse side of the liquid crystal layer (40); a light adjusting layer (22), which is provided on the first polarization plate (51a), and is configured of a red phosphor layer (22r), a green phosphor layer (22g), and a blue light transmitting layer (22b); and a light shielding layer (23), which is provided between the liquid crystal layer (40) and the light adjusting layer (22), and is disposed so as to shield a boundary portion of each of the sub-pixels from light.

Description

Liquid crystal display

The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device including a backlight that emits blue light.

The liquid crystal display device includes, for example, a thin film transistor (hereinafter referred to as “TFT”) substrate, a color filter (hereinafter referred to as “CF”) substrate, and a TFT substrate which are disposed so as to face each other. And a liquid crystal display panel constituted by a liquid crystal layer sealed between CF substrates and the like, and a backlight provided on the back side of the liquid crystal display panel. In the CF substrate, each sub-pixel constituting the pixel is provided with a colored layer colored, for example, red, green, or blue.

Here, in general, in the liquid crystal display device having the above-described configuration, the light utilization efficiency is relatively low because light from the backlight is absorbed by, for example, each colored layer constituting the CF substrate.

Therefore, in recent years, a liquid crystal display device has been proposed that achieves low power consumption by improving the light utilization efficiency.

For example, a back substrate and a front substrate disposed to face each other, a liquid crystal layer provided between the back substrate and the front substrate, a backlight unit that is provided on the back side of the back substrate and emits blue light, A red phosphor and a green phosphor that are formed on the front side of the front substrate, are emitted from the backlight unit, and emit light when excited by blue light that has passed through the liquid crystal layer and the front substrate. A liquid crystal display device including a phosphor layer is disclosed. In this liquid crystal display device, the blue pixel region in the phosphor layer is configured such that the blue light emitted from the backlight unit and passed through the liquid crystal layer and the front substrate is transmitted as it is (for example, patents). Reference 1).

JP 2007-79565 A

Here, in the liquid crystal display device described in Patent Document 1, the phosphor layer is provided on the back side of the back substrate, and the front substrate is disposed between the liquid crystal layer and the phosphor layer. And the phosphor layer are spaced apart. For this reason, for example, the light transmitted through the red sub-pixel passes through the liquid crystal layer in an oblique direction and excites the green phosphor layer provided in the adjacent green sub-pixel region (hereinafter referred to as “crosstalk”). There is a problem that the image quality is remarkably deteriorated.

The present invention has been made in view of this point, and an object of the present invention is to provide a liquid crystal display device capable of suppressing the crosstalk phenomenon and obtaining good image quality.

In order to achieve the above object, a liquid crystal display device according to the present invention includes a first substrate, a second substrate disposed opposite the first substrate, and a liquid crystal provided between the first substrate and the second substrate. A liquid crystal display panel in which red, green, and blue sub-pixels are arranged, a backlight that is provided on the first substrate side of the liquid crystal display panel and emits blue light, and a liquid crystal layer of the second substrate A polarizing plate provided on the opposite side, a red phosphor layer provided on the polarizing plate, which converts incident blue light into red light and is arranged so as to overlap the red subpixel, and incident blue Consists of a green phosphor layer that converts light into green light and overlaps the green subpixel, and a blue transmission layer that transmits incident blue light and overlaps the blue subpixel Provided between the liquid crystal layer and the light adjustment layer, and the boundary of each sub-pixel. A liquid crystal display device, characterized in that it comprises a arranged shielding layer to shield the minute.

According to this configuration, even when the liquid crystal layer and the light adjustment layer (that is, the red phosphor layer and the green phosphor layer) are arranged apart from each other, for example, the liquid crystal layer is formed in the red subpixel. Since the blue light passing in the oblique direction can be shielded by the light shielding layer, it is possible to prevent the blue light from entering the green sub-pixel and exciting the green phosphor layer. Accordingly, it is possible to suppress the crosstalk phenomenon, so that good image quality can be obtained.

In the liquid crystal display device of the present invention, a light shielding layer may be provided between the second substrate and the polarizing plate.

According to this configuration, the light shielding layer is provided between the second substrate and the polarizing plate, and the light shielding layer is disposed near the middle between the liquid crystal layer and the light adjustment layer. Blue light that has passed in an oblique direction can be effectively shielded. Therefore, the crosstalk phenomenon can be further suppressed.

In the liquid crystal display device of the present invention, a light shielding layer may be provided between the polarizing plate and the light adjustment layer.

According to this configuration, for example, the light shielding layer can be easily formed on the surface of the patterned light adjustment layer by a photolithography method or the like.

In the liquid crystal display device of the present invention, a light shielding layer may be provided on the surface of the second substrate on the liquid crystal layer side.

According to this configuration, for example, the light shielding layer can be easily formed on the surface of the patterned common electrode or the like on the second substrate by a photolithography method or the like.

In the liquid crystal display device of the present invention, the light shielding layer may be formed by a photolithography method.

In the liquid crystal display device of the present invention, an opening is formed in each subpixel, an opening is formed in the light shielding layer so as to overlap each subpixel, and the area of the opening formed in the light shielding layer is equal to each subpixel. It is preferable that it is smaller than the area of the opening part formed in this.

According to this configuration, the area of the light shielding layer that blocks the blue light that has passed through the liquid crystal layer in an oblique direction is increased, so that the blue light that has passed through the liquid crystal layer in an oblique direction can be more effectively shielded. Can do.

In the liquid crystal display device of the present invention, the light shielding layer may be formed of a metal material or a resin material in which a black pigment is dispersed.

According to this configuration, the light shielding layer can be formed from an inexpensive and versatile material.

In the liquid crystal display device of the present invention, the light shielding layer may be formed of a metal material having light reflectivity.

According to this configuration, since the light shielding layer has light reflectivity, among the blue light from the backlight, the blue light that has not passed through each opening of the light shielding layer is reflected on the light shielding layer and the backlight ( Reflected in order by the reflection sheet provided) and reused. Therefore, the utilization efficiency of blue light from the backlight is improved.

According to the present invention, in a liquid crystal display device including a phosphor layer, a crosstalk phenomenon can be suppressed and a good image quality can be obtained.

1 is a cross-sectional view of a liquid crystal display device according to a first embodiment of the present invention. FIG. 3 is a perspective view showing a positional relationship among pixels, a light shielding layer, and a phosphor layer in the liquid crystal display device according to the first embodiment of the present invention. FIG. 3 is a plan view showing a positional relationship between a light shielding layer and a boundary portion of a sub-pixel in the liquid crystal display device according to the first embodiment of the present invention. It is sectional drawing of the liquid crystal display device which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the liquid crystal display device which concerns on the 3rd Embodiment of this invention.

(First embodiment)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of a liquid crystal display device according to the first embodiment of the present invention, and FIG. 2 is a diagram illustrating a pixel, a light shielding layer, and a phosphor layer in the liquid crystal display device according to the first embodiment of the present invention. It is a perspective view which shows these positional relationships. FIG. 3 is a plan view showing the positional relationship between the light shielding layer and the boundary portion of the sub-pixel in the liquid crystal display device according to the first embodiment of the present invention.

As shown in FIG. 1, a liquid crystal display device 1 includes a liquid crystal display panel 50a in which a plurality of pixels P (see FIG. 2) are arranged in a matrix, and a front surface (upper surface in the figure) and a rear surface (rear surface) of the liquid crystal display panel 50a. , A pair of a first polarizing plate 51a and a second polarizing plate 51b respectively attached to the lower surface of the figure. Further, the liquid crystal display device 1 is provided on the back side of the liquid crystal display panel 50a and is provided on the surface of the backlight 70 that emits blue light Lb and the first polarizing plate 51a, and adjusts the blue light Lb from the backlight 70. And a phosphor substrate 80 on which the light adjustment layer 22 is formed.

In each pixel P, as shown in FIG. 2, a red subpixel Pr that performs red gradation display, a green subpixel Pg that performs green gradation display, and a blue gradation, which are formed to have the same size. Blue sub-pixels Pb that perform display are arranged.

Further, as shown in FIG. 2, the red subpixel Pr has an opening Ar, the green subpixel Pg has an opening Ag, and the blue subpixel Pb has an opening. Ab is formed.

As shown in FIG. 1, the liquid crystal display panel 50 a includes a TFT substrate 20 that is a first substrate, a counter substrate 30 that is a second substrate disposed to face the TFT substrate 20, and the TFT substrate 20 and the counter substrate 30. And a liquid crystal layer 40 provided therebetween. In addition, the liquid crystal display panel 50 a adheres the TFT substrate 20 and the counter substrate 30 to each other, and seals (not shown) provided in a frame shape to enclose the liquid crystal layer 40 between the TFT substrate 20 and the counter substrate 30. ).

As shown in FIG. 1, the TFT substrate 20 includes an insulating substrate 10 such as a glass substrate, a plurality of gate lines (not shown) provided on the insulating substrate 10 so as to extend in parallel to each other, and orthogonal to each gate line. And a plurality of source lines 11 provided so as to extend in parallel to each other. The TFT substrate 20 covers a plurality of TFTs (not shown) provided for each intersecting portion of each gate line and each source line 11, that is, for each subpixel Pr, Pg, and Pb, and each TFT. A protective film (not shown) provided in such a manner, a plurality of pixel electrodes (not shown) provided in a matrix on the protective film and connected to each TFT, and an orientation provided so as to cover each pixel electrode A film (not shown).

As shown in FIG. 1, the counter substrate 30 includes an insulating substrate 15 such as a glass substrate, a common electrode (not shown) provided on the insulating substrate 15, and an alignment film (not shown) provided so as to cover the common electrode. As shown).

The liquid crystal layer 40 is made of a nematic liquid crystal material having electro-optical characteristics.

The backlight 70 is provided on the TFT substrate 20 side of the liquid crystal display panel 50a, and includes a linear light source (not shown) that emits blue light, and a light guide plate (not shown) provided on the side of the linear light source. A reflection sheet (not shown) provided below the light guide plate, a diffusion sheet (not shown) provided on the light guide plate, and a prism sheet (not shown) provided on the diffusion sheet. .

And the backlight 70 is comprised so that the blue light from a linear light source may be radiate | emitted as blue light Lb (refer FIG. 1) through a light-guide plate, a reflective sheet, a diffusion sheet, and a prism sheet. Here, each linear light source includes a plurality of blue LEDs (Light-Emitting-Diodes) provided in a row that emits blue light.

The first polarizing plate 51a is provided on the opposite side of the counter substrate 30 from the liquid crystal layer 40, and the second polarizing plate 51b is provided on the opposite side of the TFT substrate 20 from the liquid crystal layer 40. These first and second

polarizing plates

51a and 51b are, for example, a pair of supports (not shown) formed of a triacetylcellulose film and the like, and polyvinyl films dyed with iodine provided between the supports. A polarizer layer (not shown) including a polarizer having a unidirectional polarization axis formed of an alcohol film or the like, and a transparent protective film (not shown) provided on the surface of the support are provided.

As shown in FIG. 1, the phosphor substrate 80 includes an insulating substrate 35 such as a glass substrate, and a light adjustment layer 22 provided on the insulating substrate 35. As shown in FIG. 1, the light adjustment layer 22 is provided on the surface 55 of the first polarizing plate 51a opposite to the side on which the liquid crystal layer 40 is provided.

As shown in FIGS. 1 and 2, the light adjustment layer 22 includes a red phosphor layer 22r provided so as to overlap the red subpixel Pr and a green phosphor provided so as to overlap the green subpixel Pg. A layer 22g and a blue transmission layer 22b provided so as to overlap the blue subpixel Pb are provided.

As shown in FIG. 1, the red phosphor layer 22r is a transparent resin layer (thickness of about 10 μm to several tens of μm) in which a phosphor for converting blue light Lb incident from the backlight 70 into red light Lr is dispersed. It is.

Further, as shown in FIG. 1, the green phosphor layer 22g is a transparent resin layer (thickness of 10 μm to several tens of μm) in which a phosphor for converting the blue light Lb incident from the backlight 70 into the green light Lg is dispersed. Degree).

Further, as shown in FIG. 1, the blue transmissive layer 22b is a transparent resin layer (thickness of about 10 μm to several tens of μm) configured to transmit part of the blue light Lb from the backlight 70 as the blue light Ltb. It is.

As described above, in the present embodiment, the red and green subpixels Pr and Pg are provided with the red phosphor layer 22r and the green phosphor layer 22g that convert blue light into red light and green light, respectively. The blue transmission layer 22b is provided in the sub-pixel Pb. In each of the red and green subpixels Pr and Pg, wavelength conversion is performed by the red phosphor layer 22r and the green phosphor layer 22g, and wavelength conversion by the phosphor is not performed in the blue subpixel Pb. It has become.

In the present embodiment, the transparent resin layer is exemplified as the blue transmission layer 22b. However, the blue light Lb from the backlight 70 is dispersed by dispersing transparent beads having a refractive index different from that of the transparent resin layer in the transparent resin layer. May be transmitted while being diffused, or may be a transparent inorganic material layer or a space layer.

In the liquid crystal display device 1 having the above-described configuration, a predetermined value is set for each subpixel Pr, Pg, and Pb in the liquid crystal layer 40 positioned between each pixel electrode on the TFT substrate 20 and the common electrode on the counter substrate 30. The transmittance of the red light Lr, the green light Lg, and the blue light Ltb transmitted through the liquid crystal display panel 50a is adjusted for each subpixel Pr, Pg, and Pb by changing the alignment state of the liquid crystal layer 40 by applying a voltage. Thus, an image display is performed.

Here, in the present embodiment, as shown in FIGS. 1 to 3, each sub-pixel (that is, each of the sub-pixels Pr, red, green, and blue, red, green) between the counter substrate 30 and the first polarizing plate 51a. It is characterized in that a light shielding layer 23 is provided so as to shield the boundary region between Pg and Pb).

As shown in FIG. 2, the light shielding layer 23 includes an opening Kr provided so as to overlap the red subpixel Pr, an opening Kg provided so as to overlap the green subpixel Pg, and a blue subpixel. An opening Kb provided to overlap Pb is provided.

1 to 3, a boundary region 24 between the red subpixel Pr and the green subpixel Pg and a boundary region 25 between the green subpixel Pg and the blue subpixel Pb are included in the light shielding layer. 23 (that is, the portion of the light shielding layer 23 other than the openings Kr, Kg, and Kb) is shielded from light.

With such a configuration, even when the liquid crystal layer 40 and the phosphor layer (that is, the red phosphor layer 22r and the green phosphor layer 22g) are spaced apart, as shown in FIG. Since the blue light Lb that has passed through the liquid crystal layer 40 in the red sub-pixel Pr in the oblique direction can be shielded by the light-shielding layer 23, the blue light Lb is incident on the adjacent green sub-pixel Pg, and the green phosphor Excitation of the layer 22g can be prevented. Therefore, it is possible to suppress the crosstalk phenomenon and obtain a good image quality.

In addition, as shown in FIG. 1, since the blue light Lb that has passed through the liquid crystal layer 40 in the green subpixel Pg in the oblique direction can be shielded by the light shielding layer 23, the red subpixel adjacent to the blue light Lb can be shielded. It is possible to prevent the red phosphor layer 22r from being excited by entering the Pr.

Further, as shown in FIG. 1, since the blue light Lb that has passed through the liquid crystal layer 40 in the oblique direction in the blue sub-pixel Pb can be shielded by the light-shielding layer 23, the green sub-pixel adjacent to the blue light Lb. It is possible to prevent the green phosphor layer 22g from being excited by entering the Pg.

The light shielding layer 23 is made of a metal material such as Ta (tantalum), Cr (chromium), Mo (molybdenum), Ni (nickel), Ti (titanium), Cu (copper), Al (aluminum), or a black pigment such as carbon. Is formed of a dispersed resin material.

Further, by forming the light shielding layer 23 from a light reflective metal material (for example, an aluminum film), the blue light Lb from the backlight 70 passes through the openings Kr, Kg, Kb of the light shielding layer 23. The blue light Lb that has not been reflected is sequentially reflected and reused by the light shielding layer 23 and the backlight 70 (the reflective sheet provided on the light shielding layer 23), so that the utilization efficiency of the blue light Lb from the backlight 70 is improved. To do.

In the present embodiment, the areas of the openings Kr, Kg, and Kb formed in the red phosphor layer 22r, the green phosphor layer 22g, and the blue transmission layer 22b are represented by red subpixels Pr and green subpixels, respectively. It is preferable to set the area smaller than each area of the openings Ar, Ag, and Ab formed in the pixel Pg and the blue sub-pixel Pb.

This is because the part of the light shielding layer 23 that shields the blue light Lb that has passed through the liquid crystal layer 40 obliquely when the area of the openings Kr, Kg, Kb is smaller than the area of each of the openings Ar, Ag, Ab. This is because the area of the light shielding layer 23 other than the openings Kr, Kg, and Kb is increased, so that the blue light Lb that has passed through the liquid crystal layer 40 in an oblique direction can be further shielded.

Table 1 shows the calculated value of the crosstalk ratio when the light shielding layer 23 having a different opening area is provided in the liquid crystal display device 1 of the present embodiment. The crosstalk ratio was calculated using a ray tracing simulation apparatus (manufactured by Optical Research Associate, trade name: LightTools 7.1.0) under the following conditions. Further, out of the total light amount L of the blue light Lb emitted from the backlight 70 in the red subpixel Pr, the light amount L2 incident on the phosphor layer other than the red phosphor layer 22r (that is, the green phosphor layer 22g) is used. A value (L2 / L1) divided by the light amount L1 incident on the red phosphor layer 22r was calculated as the crosstalk ratio. As a comparative example, the same calculation was performed for the case where the light shielding layer 23 was not provided.

<Calculation conditions>
Size of each sub-pixel and phosphor layer: 108 μm × 324 μm
Opening size of each sub-pixel: 98 μm × 314 μm
Size of opening of light shielding layer: 98 μm × 314 μm, 88 μm × 304 μm, 78 μm × 294 μm
Light-shielding layer thickness: 1μm
TFT substrate thickness: 400 μm
Counter substrate thickness: 100 μm
Liquid crystal layer thickness: 5 μm
Thickness of the first and second polarizing plates: 100 μm
Total amount of blue light emitted by the backlight L: 0.0347 [W]
Characteristics of blue light emitted by a backlight: light having an alignment characteristic defined by a Gaussian function having a maximum brightness in the front direction and a full width at half maximum of 20 ° in all directions

As shown in Table 1, it can be seen that when the light shielding layer 23 is provided, the crosstalk phenomenon can be suppressed as compared with the case where the light shielding layer 23 is not provided. Further, by making the areas of the openings Kr, Kg, Kb of the light shielding layer 23 smaller than the areas of the openings Ar, Ag, Ab formed in the sub-pixels Pr, Pg, Pb, the crosstalk phenomenon is further reduced. It turns out that it can suppress further.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. FIG. 4 is a cross-sectional view of a liquid crystal display device according to the second embodiment of the present invention. In addition, about the component similar to the said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. Further, the positional relationship between the pixel, the light shielding layer, and the phosphor layer, and the positional relationship between the light shielding layer and the boundary portion of the subpixel are the same as those described in the first embodiment. Detailed description is omitted.

In the liquid crystal display device 60 of the present embodiment, as shown in FIG. 4, each subpixel (that is, each subpixel Pr of red, green, and blue, between the first polarizing plate 51 a and the light adjustment layer 22). It is characterized in that a light shielding layer 23 is provided so as to shield the boundary region between Pg and Pb).

With such a configuration, the light shielding layer 23 can be easily formed on the surface of the patterned light adjusting layer 22 by, for example, a photolithography method.

For example, a positive photosensitive resin in which black pigments such as carbon fine particles are dispersed is applied to the entire substrate of the insulating substrate 35 on which the patterned light adjustment layer 22 is formed by spin coating, for example. After the exposed photosensitive resin is exposed through a photomask, the light shielding layer 23 can be formed by developing and heating.

Further, as in the case of the first embodiment, even when the liquid crystal layer 40 and the phosphor layer (that is, the red phosphor layer 22r and the green phosphor layer 22g) are arranged apart from each other. As shown in FIG. 4, since the blue light Lb that has passed through the liquid crystal layer 40 in the red subpixel Pr in the oblique direction can be shielded by the light shielding layer 23, the green subpixel Pg adjacent to the blue light Lb. , And the green phosphor layer 22g can be prevented from being excited. Therefore, the crosstalk phenomenon can be suppressed.

Further, as shown in FIG. 4, in the green subpixel Pg, the blue light Lb that has passed through the liquid crystal layer 40 in the oblique direction can be shielded by the light shielding layer 23, and therefore the red subpixel adjacent to the blue light Lb. It is possible to prevent the red phosphor layer 22r from being excited by entering the Pr.

Further, as shown in FIG. 4, since the blue light Lb that has passed through the liquid crystal layer 40 in the oblique direction in the blue sub-pixel Pb can be shielded by the light-shielding layer 23, the green sub-pixel adjacent to the blue light Lb. It is possible to prevent the green phosphor layer 22g from being excited by entering the Pg.

Similarly to the case of the first embodiment, Table 2 shows calculated values of the crosstalk ratio when the light shielding layer 23 having a different opening area is provided in the liquid crystal display device 60 of the present embodiment. Note that the calculation condition of the crosstalk ratio is the same as that in the above-described first embodiment, and thus detailed description thereof is omitted here.

As shown in Table 2, it can be seen that when the light shielding layer 23 is provided, the crosstalk phenomenon can be suppressed as compared with the case where the light shielding layer 23 is not provided. Further, by making the areas of the openings Kr, Kg, Kb of the light shielding layer 23 smaller than the areas of the openings Ar, Ag, Ab formed in the sub-pixels Pr, Pg, Pb, the crosstalk phenomenon is further reduced. It turns out that it can suppress.

(Third embodiment)
Next, a third embodiment of the present invention will be described. FIG. 5 is a cross-sectional view of a liquid crystal display device according to the third embodiment of the present invention. In addition, about the component similar to the said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. Further, the positional relationship between the pixel, the light shielding layer, and the phosphor layer, and the positional relationship between the light shielding layer and the boundary portion of the subpixel are the same as those described in the first embodiment. Detailed description is omitted.

In the liquid crystal display device 65 of the present embodiment, as shown in FIG. 5, each subpixel (that is, each of red, green, and blue subpixels Pr, Pg, etc.) is formed on the surface 30 a of the counter substrate 30 on the liquid crystal layer 40 side. It is characterized in that a light shielding layer 23 is provided so as to shield the boundary region of Pb).

Such a configuration makes it possible to easily form the light shielding layer 23 on the surface of the common electrode or the like patterned on the counter substrate 30 by, for example, photolithography.

For example, a positive photosensitive resin in which black pigments such as carbon fine particles are dispersed is applied to the entire substrate of the counter substrate 30 on which the patterned common electrode is formed by spin coating, for example. The light shielding layer 23 can be formed by exposing the photosensitive resin through a photomask and then developing and heating.

Further, as in the case of the first embodiment, even when the liquid crystal layer 40 and the phosphor layer (that is, the red phosphor layer 22r and the green phosphor layer 22g) are arranged apart from each other. As shown in FIG. 5, since the blue light Lb that has passed through the liquid crystal layer 40 in the red sub-pixel Pr in the oblique direction can be shielded by the light-shielding layer 23, the green sub-pixel Pg adjacent to the blue light Lb. , And the green phosphor layer 22g can be prevented from being excited. Therefore, the crosstalk phenomenon can be suppressed.

Further, as shown in FIG. 5, in the green subpixel Pg, the blue light Lb that has passed through the liquid crystal layer 40 in the oblique direction can be shielded by the light shielding layer 23, and therefore the red subpixel adjacent to the blue light Lb. It is possible to prevent the red phosphor layer 22r from being excited by entering the Pr.

Further, as shown in FIG. 5, in the blue sub-pixel Pb, the blue light Lb that has passed through the liquid crystal layer 40 in the oblique direction can be shielded by the light-shielding layer 23, so that the blue sub-pixel Pb is adjacent to the green sub-pixel. It is possible to prevent the green phosphor layer 22g from being excited by entering the Pg.

Similarly to the case of the first embodiment, Table 3 shows calculated values of the crosstalk ratio when the light shielding layer 23 having a different opening area is provided in the liquid crystal display device 60 of the present embodiment. Note that the calculation condition of the crosstalk ratio is the same as that in the above-described first embodiment, and thus detailed description thereof is omitted here.

As shown in Table 3, it can be seen that when the light shielding layer 23 is provided, the crosstalk phenomenon can be suppressed as compared with the case where the light shielding layer 23 is not provided. Further, by making the areas of the openings Kr, Kg, Kb of the light shielding layer 23 smaller than the areas of the openings Ar, Ag, Ab formed in the sub-pixels Pr, Pg, Pb, the crosstalk phenomenon is further reduced. It turns out that it can suppress.

From Tables 1 to 3, the crosstalk phenomenon can be suppressed most when the light shielding layer 23 is provided between the counter substrate 30 and the first polarizing plate 51a shown in FIG. 1 (that is, the crosstalk ratio L2 / L1 is the smallest).

This is because the light-shielding layer 23 is provided between the liquid crystal layer 40 and the light adjustment layer 22 in any case in the liquid

crystal display devices

1, 60, 65 shown in FIGS. In the liquid crystal display device 1 shown in FIG. 1, the light shielding layer 23 is provided between the counter substrate 30 and the first polarizing plate 51 a, and the light shielding layer 23 is in the vicinity of the middle between the liquid crystal layer 40 and the light adjustment layer 22. Therefore, it is considered that the blue light Lb that has passed through the liquid crystal layer 40 in the oblique direction can be shielded most effectively by the light shielding layer 23.

Note that the above embodiment may be modified as follows.

In each of the above embodiments, a liquid crystal display device including a TFT substrate has been exemplified. However, the present invention is also applied to a liquid crystal display device including another active matrix substrate, a liquid crystal display device of a passive matrix driving system, and the like. be able to.

In each of the above embodiments, the liquid crystal display device in which the red layer, the green layer, and the blue layer on the counter substrate are omitted is illustrated. However, the present invention is directed to the counter in which the red layer, the green layer, and the blue layer are provided. The present invention can also be applied to a liquid crystal display device provided with a substrate.

As described above, the present invention is useful for a liquid crystal display device including a backlight that emits blue light.

1 Liquid crystal display device 20 TFT substrate (first substrate)
22 light adjustment layer 22b blue transmission layer 22g green phosphor layer 22r red phosphor layer 23 light shielding layer 24 boundary region 25 boundary region 30 counter substrate (second substrate)
30a Surface of the counter substrate on the liquid crystal layer side 35 Insulating substrate 40 Liquid crystal layer 50a Liquid crystal display panel 51a First polarizing plate (polarizing plate)
60 Liquid crystal display device 65 Liquid crystal display device 70 Backlight 80 Phosphor substrate

Claims

A first substrate; a second substrate disposed opposite to the first substrate; and a liquid crystal layer provided between the first substrate and the second substrate, each of red, green, and blue A liquid crystal display panel in which sub-pixels are arranged;
A backlight that is provided on the first substrate side of the liquid crystal display panel and emits blue light;
A polarizing plate provided on the opposite side of the liquid crystal layer of the second substrate;
Provided on the polarizing plate, converts the incident blue light into red light, a red phosphor layer disposed so as to overlap the red sub-pixel, and converts the incident blue light into green light, A light adjustment layer configured by a green phosphor layer disposed so as to overlap the green subpixel and a blue transmission layer disposed so as to transmit the incident blue light and overlap the blue subpixel. When,
A liquid crystal display device comprising: a light shielding layer provided between the liquid crystal layer and the light adjustment layer and arranged to shield a boundary portion between the sub-pixels.
The liquid crystal display device according to claim 1, wherein the light shielding layer is provided between the second substrate and the polarizing plate.
The liquid crystal display device according to claim 1, wherein the light shielding layer is provided between the polarizing plate and the light adjusting layer.
The liquid crystal display device according to claim 1, wherein the light shielding layer is provided on a surface of the second substrate on the liquid crystal layer side.
The liquid crystal display device according to claim 3 or 4, wherein the light shielding layer is formed by a photolithography method.
An opening is formed in each subpixel, an opening is formed in the light shielding layer so as to overlap each subpixel, and an area of the opening formed in the light shielding layer is formed in each subpixel. The liquid crystal display device according to any one of claims 1 to 5, wherein the liquid crystal display device is smaller than an area of the formed opening.
7. The liquid crystal display device according to claim 1, wherein the light shielding layer is formed of a metal material or a resin material in which a black pigment is dispersed.
The liquid crystal display device according to claim 7, wherein the light shielding layer is formed of the metal material having light reflectivity.