Abstract: An IPS system liquid crystal display device is provided to prevent reliability for a seal portion from lowering, which is caused by the fact that an overcoat film at a portion where an alignment film is not present is deteriorated by ultraviolet light during optical alignment process. An alignment film 113 subjected to optical alignment is formed above each surface of a TFT substrate 100 and of a counter substrate 200, the alignment film 113 on the side of the TFT substrate 100 is not formed in the seal portion, and a sealant 150 is bonded to an inorganic insulating film 109. On the side of the counter substrate 200, the alignment film 113 is formed on an overcoat film 203 and the sealant 150 is bonded to the alignment film 113.

Abstract: in a liquid crystal display device, a common electrode is formed on an organic passivation film, an interlayer insulating film is formed on the common electrode, a pixel electrode with a slit is formed on the interlayer insulating film, and a through hole is formed in the organic passivation film and the interlayer insulating film, so that the pixel electrode is connected to a source electrode of a TFT through the through hole. Further, the taper angle around the upper base of the through hole is smaller than the taper angle around the lower base. Thus, the alignment film material can easily flow into the through hole when the diameter of the through hole is reduced to connect the pixel and source electrodes, preventing display defects such as uneven brightness due to the absence of the alignment film or due to the alignment film irregularity around the through hole.

Abstract: In a liquid crystal display device including: TFT substrate; color filter; counter electrode; interlayer insulation film; pixel electrode; alignment film; liquid crystal layer; counter substrate; and Si semiconductor layer. The color filter, counter electrode, interlayer insulation film, pixel electrode, and alignment film being formed on the side where the TFT substrate is provided, the counter substrate being disposed in facing relation to the TFT substrate with the liquid crystal layer put between the counter substrate and TFT substrate, the Si semiconductor layer is formed between the pixel electrode and interlayer insulation film. Even when light from a backlight is absorbed by the color filter and sufficient light cannot reach the alignment film, electric charges accumulated on the alignment film can escape to the pixel electrode in an early stage by the Si semiconductor layer formed under the alignment film, thereby capable of erasing the afterimage in an early stage.

Abstract: A liquid crystal display device including an alignment film which has been optically aligned is configured that the liquid crystal has negative dielectric anisotropy, an absolute value of which is equal to or smaller than 5. The alignment film is subjected to an optical alignment process to exhibit the optical alignment property, and includes a first film located at a side in contact with the liquid crystal, and a second film below the first film, which is not optically aligned to have no alignment property. The alignment film is formed by applying a mixture of a first material for forming the first film and a second material for forming the second film to the substrate. The first material for the alignment film accounts for 10 wt. % or more and less than 40 wt. % of a total weight of the first and the second materials.

Abstract: A liquid crystal display device includes a TFT substrate having a first alignment film formed on part of an inorganic insulating film, an overcoat film formed on a black matrix, a counter substrate having a second alignment film formed on the overcoat film, and a seal portion including a sealant. The TFT substrate is bonded to the counter substrate by the sealant. The sealant is bonded to the inorganic insulating film at the seal portion on the side where the TFT substrate is formed, with the first alignment film not being provided on the side, and, in the seal portion on the side where the counter substrate is formed, the sealant is bonded to the second alignment film but, is not bonded to the overcoat film.

Abstract: A liquid crystal display device has a liquid crystal display panel including pixels each having an active device, a pixel electrode, a common electrode and a liquid crystal layer arranged in a dot matrix array. The liquid crystal display panel has a first substrate, a second substrate, and a liquid crystal layer provided between the first substrate and the second substrate. The first substrate has the active device, the pixel electrode, the common electrode and a first alignment film. The second substrate has a second alignment film. The first alignment film and the second alignment film are respectively a photo alignment film formed by irradiating a photo decomposition type insulating film with light. The second alignment film has a thickness of at least 10 nm and no greater 50 nm and is thinner than the first alignment film.

Abstract: An alignment film is given a 2-layer structure comprising a photoalignment film that is photoalignable and a low-resistivity alignment film whose resistivity is smaller than that of the photoalignment film. The photoalignment film is formed by a polyimide whose precursor is polyamide acid alkyl ester, the number molecular weight of the photoalignment film is large, and the stability of alignment of the photoalignment film by photoalignment is excellent. The low-resistivity alignment film is formed by a polyimide whose precursor is polyamide acid, the number molecular weight of the low-resistivity alignment film is small, and the resistivity of the low-resistivity alignment film is small. The 2-layer structure alignment film can be maintaining an excellent photoalignment characteristic, so DC afterimages can be controlled.

Abstract: In a liquid crystal display device, a common electrode is formed on an organic passivation film, an interlayer insulating film is formed on the common electrode, a pixel electrode with a slit is formed on the interlayer insulating film, and a through hole is formed in the organic passivation film and the interlayer insulating film, so that the pixel electrode is connected to a source electrode of a TFT through the through hole. Further, the taper angle around the upper base of the through hole is smaller than the taper angle around the lower base. Thus, the alignment film material can easily flow into the through hole when the diameter of the through hole is reduced to connect the pixel and source electrodes, preventing display defects such as uneven brightness due to the absence of the alignment film or due to the alignment film irregularity around the through hole.

Abstract: A liquid crystal display device includes a TFT substrate having a first alignment film and an opposing substrate having a second alignment film with liquid crystals sandwiched therebetween. One of the first and second alignment films, comprises a first polyimide produced via polyamide acid ester containing cyclobutane as a precursor and a second polyimide produced via polyamide acid as a precursor. The polyamide acid has a higher polarity than that of the polyamide acid ester. The one of the first and second alignment films is responsive to photo-alignment. A first side of the one of the first and second alignment films is adjacent to the liquid crystals, and a second side thereof is closer to one of the TFT substrate and the counter substrate than the first side. The first side contains more of the first polyimide and less of the second polyimide than the second side.

Abstract: The present invention prevents the shaving of an alignment film caused by a columnar spacer in a liquid crystal display device of an IPS method using photo-alignment. A plinth higher than a pixel electrode is formed at a part where a columnar spacer formed over a counter substrate touches a TFT substrate. When an alignment film of a double-layered structure is applied over the pixel electrode and the plinth, the thickness of the alignment film over the plinth reduces by a leveling effect. When photo-alignment is applied in the state, a photodegraded upper alignment film over the plinth disappears and a lower alignment film having a high mechanical strength remains. As a result, it is possible to prevent the shaving of the alignment film.

Abstract: A display device includes a first substrate having a plurality of TFTs, a passivation film, and a plurality of pixel electrodes, and a second substrate arranged with a gap with the first substrate. The passivation film has a plurality of contact holes, and the plurality of pixel electrodes are connected to the plurality of TFTs via the plurality of contact holes. The second substrate has a plurality of columnar spacers for ensuring the gap with the first substrate, and a plurality of columnar projections for misalignment prevention formed at positions corresponding to the contact holes. The number of the plurality of columnar projections is less than the number of the plurality of columnar spacers.

Abstract: A reliability of seal portion of a liquid crystal display device can be improved by the following structure. A liquid crystal display device includes: a TFT substrate which includes a display region and a terminal part, and has an inorganic insulating film formed on an organic passivation film and an alignment film formed over the inorganic insulating film; a counter substrate, the TFT substrate and the counter substrate bonded together by a sealing material formed at a seal part surrounding the display region; and a liquid crystal sealed inside. At the seal part, a transparent conductive oxide film is formed between the inorganic insulating film and the alignment film. The transparent conductive oxide film exists inside an edge of the TFT substrate and hence, the edge of the TFT substrate is free of the transparent conductive oxide film.

Abstract: An alignment film is given a 2-layer structure comprising a photoalignment film that is photoalignable and a low-resistivity alignment film whose resistivity is smaller than that of the photoalignment film. The photoalignment film is formed by a polyimide whose precursor is polyamide acid alkyl ester, the number molecular weight of the photoalignment film is large, and the stability of alignment of the photoalignment film by photoalignment is excellent. The low-resistivity alignment film is formed by a polyimide whose precursor is polyamide acid, the number molecular weight of the low-resistivity alignment film is small, and the resistivity of the low-resistivity alignment film is small. The 2-layer structure alignment film can be maintaining an excellent photoalignment characteristic, so DC afterimages can be controlled.

Abstract: A display device includes a first substrate, a second substrate and liquid crystals therebetween, the first substrate having a flat portion, an alignment film, and a concavo-convex pedestal formed in a pixel region, wherein the concavo-convex pedestal having at least two convex portions and recessed portions, and the at least two convex portions of the concavo-convex pedestal are at a position lower than a position of the flat portion. A thickness of the alignment film on the convex portions is less than a thickness of the alignment film on the recessed portions, and a second substrate has a columnar spacer which contacts the at least two convex portions of the concavo-convex pedestal.

Abstract: A liquid crystal display device includes a first substrate, a first alignment film formed over the first substrate, a second substrate, a second alignment film formed over the second substrate, a liquid crystal layer sandwiched between the first alignment film and the second alignment film, and a projecting portion formed over the second substrate. The first alignment film is a photo alignment film, and a thickness “d2” of the second alignment film over the projecting portion and a film thickness “d1” of a portion of the first alignment film facing the projecting portion satisfy formula (1) and (2): 0 nm<d2<30 nm ??(1); d2<d1 ??(2).

Abstract: A liquid crystal display device includes a TFT substrate having a first alignment film and an opposing substrate having a second alignment film with liquid crystals sandwiched therebetween. One of the first and second alignment films, comprises a first polyimide produced via polyamide acid ester containing cyclobutane as a precursor and a second polyimide produced via polyamide acid as a precursor. The polyamide acid has a higher polarity than that of the polyamide acid ester. The one of the first and second alignment films is responsive to photo-alignment. A first side of the one of the first and second alignment films is adjacent to the liquid crystals, and a second side thereof is closer to one of the TFT substrate and the counter substrate than the first side. The first side contains more of the first polyimide and less of the second polyimide than the second side.

Abstract: The present invention prevents the shaving of an alignment film caused by a columnar spacer in a liquid crystal display device of an IPS method using photo-alignment. A plinth higher than a pixel electrode is formed at a part where a columnar spacer formed over a counter substrate touches a TFT substrate. When an alignment film of a double-layered structure is applied over the pixel electrode and the plinth, the thickness of the alignment film over the plinth reduces by a leveling effect. When photo-alignment is applied in the state, a photodegraded upper alignment film over the plinth disappears and a lower alignment film having a high mechanical strength remains. As a result, it is possible to prevent the shaving of the alignment film.

Abstract: A method for fabricating a liquid crystal display device including a TFT substrate having an alignment film formed thereon, an opposing substrate, and a liquid crystal layer sandwiched therebetween. The alignment film on the TFT substrate includes a photolytic polymer made from a first precursor including cyclobutane, and a non-photolytic polymer made from a second precursor. The method includes the steps of depositing a mixture material including the first precursor and the second precursor in which the second precursor settles more on an upper surface of the TFT substrate than the first precursor, imidizing the mixture material, and irradiating the mixture material with ultraviolet light for photo-alignment, and after irradiating, heating the mixture material to form the alignment film.

Abstract: A liquid crystal display device has a liquid crystal display panel including pixels each having an active device, a pixel electrode, a common electrode and a liquid crystal layer arranged in a dot matrix array. The liquid crystal display panel has a first substrate, a second substrate, and a liquid crystal layer provided between the first substrate and the second substrate. The first substrate has the active device, the pixel electrode, the common electrode and a first alignment film. The second substrate has a second alignment film. The first alignment film and the second alignment film are respectively a photo alignment film formed by irradiating a photo decomposition type insulating film with light. The second alignment film has a thickness of at least 10 nm and no greater 50 nm and is thinner than the first alignment film.

Abstract: A liquid crystal display device includes: a pair of substrates at least one of which is transparent; a liquid crystal layer disposed between the pair of substrates; an electrode group formed on at least one substrate of the pair of substrates, for applying an electric field to the liquid crystal layer; a plurality of active elements connected to the electrode group; and a liquid crystal alignment film disposed on at least one substrate of the pair of substrates, in which the liquid crystal alignment film, which is formed by a photo-alignment process, contains polyimide formed using tetracarboxylic acid dianhydride and/or diamine each having a specific chemical structure.