JP2004109899A - Composite phase difference optical element, its manufacturing method and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite phase difference optical element for effectively compensating the change of the optical characteristics of liquid crystal simultaneously while realizing thinning and cost reduction, and to provide its manufacturing method and a liquid crystal display device provided with the composite phase difference optical element. <P>SOLUTION: The composite phase difference optical element 10 comprises a first phase difference film 12 of a thickness usable as a base material, for which a normal direction erected on the surface of the film is practically an optical axis and has negative uniaxiality; and a second phase difference film 14 provided on the first phase difference film 12 for which the normal direction erected on the surface of the film is practically the optical axis and has the negative uniaxiality. <P>COPYRIGHT: (C)2004,JPO

Description

【００６８】
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【００７８】
又、カイラル剤としては、例えば一般化学式（１２）〜（１４）に示されるようなカイラル剤を用いることができる。尚、一般化学式（１２）、（１３）で示されるカイラル剤の場合、Ｘは２〜１２（整数）であることが望ましく、又、一般化学式（１４）で示されるカイラル剤の場合、Ｘが２〜５（整数）であることが望ましい。
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【化１２】

【００８０】
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【００８１】
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【００８２】
又、オリゴマー分子を用いる場合は、特開昭５７−１６５４８０号公報で開示されているようなコレステリック相を有する環式オルガノポリシロキ酸化合物等が望ましい。
【００８３】
まず、コレステリック位相差層形成工程について説明する。
【００８４】
この実施の形態の例では、重合性モノマー分子又は重合性オリゴマー分子に、カイラル剤を数％〜１０％程度入れることによりコレステリック液晶を得る。尚、カイラル剤の種類を変えてカイラルパワーを変えるか、あるいは、カイラル剤の濃度を変化させることにより、コレステリック液晶の選択反射波長帯域を調整することができる。
【００８５】
最初に、図４（Ａ）に示されるように、ＴＡＣフィルム３２上に配向膜１７を形成しておき、その上に、図４（Ｂ）に示されるように、重合性モノマー分子（又は重合性オリゴマー分子）１８をコーティングし、配向膜１７の配向規制力によって配向（このとき、コーティングされた重合性モノマー分子等はコレステリック液晶層を構成している）させる。なお、コーティング液に溶媒を含む場合は、コーティング工程後に溶媒を除去するための乾燥工程が含まれる。又、前記ＴＡＣフィルム３２は、配向規制力の方向が膜上の全範囲で実質的に同一とされている。
【００８６】
次に、上記配向状態のままで、図４（Ｃ）に示されるように、重合性モノマー分子（又は重合性オリゴマー分子）１８を、予め添加しておいた光開始材と外部から照射した紫外線によって重合を開始させるか、又は電子線で直接重合を開始させて、３次元架橋（ポリマー化）させることにより、コレステリック位相差層３４を得る。
【００８７】
配向膜１７の配向規制力の方向を同配向膜１７の膜上の全範囲で実質的に一致させておけば、これと接触する側の表面３４Ａにおける液晶分子のダイレクターの方向を、該面内で実質的に一致させることができる。
【００８８】
なお、配向膜１７は、従来知られている方法で作成する。例えば、前述のようにＴＡＣフィルム３２上にＰＩ（ポリイミド）又はＰＶＡ（ポリビニルアルコール）を成膜し、ラビングする方法、ＴＡＣフィルム３２上に光配向膜となる高分子化合物を成膜し、偏光ＵＶ（紫外線）を照射する方法、延伸したＰＥＴ（ポリエチレンテレフタレート）等のフィルムを用いる方法等がある。
【００８９】
次に、ネマチック位相差層形成工程について説明する。
【００９０】
まず、図４（Ｄ）に示されるように、所定の温度でネマチック構造の液晶相とした重合性モノマー分子（又は重合性オリゴマー分子）１９を別途用意し、これをコレステリック位相差層３４の上に直接コーティングし、該コーティングした液晶の厚さ方向の一方の表面における液晶分子のダイレクターの方向を、前記３次元架橋させたコレステリック位相差層３４の表面の配向規制力によって規制する（このとき、コーティングされた重合性モノマー分子等はネマチック液晶層を構成している）。この状態で、図４（Ｅ）に示されるように、前述と同様の紫外線照射又は電子線単独照射によって３次元架橋させて固化させ、ネマチック位相差層３６を得る。なお、コーティング液に溶媒を含む場合は、コーティング工程後に溶媒を除去するための乾燥工程が含まれる。
【００９１】
これにより、複合位相差光学素子３０が完成する。
【００９２】
本発明の実施形態の例に係る複合位相差光学素子３０の製造方法によれば、複合位相差光学素子３０の製造が容易となる。しかも、第２位相差フィルム３４の表面３４Ｂが有する配向規制力を用いて第３位相差フィルム３６の液晶分子を配向させることができるため、生産性の向上が可能である。なお、表面３４Ｂ自体の配向規制力が弱い場合は、ラビングしても良い。
【００９３】
なお、図５に示すように、ネマチック位相差フィルム３６と隣接するコレステリック位相差フィルム３４の表面３４Ｂに、更に、配向膜１７Ａを積層することで、ネマチック位相差層３６の配向を行っても、同様の効果を得ることができる。
【００９４】
次に、図６を参照して位相差層の材料としてポリマー（高分子）液晶を用いる場合について説明する。
【００９５】
まず、コレステリック位相差層形成工程について説明する。
【００９６】
この材料としては、液晶ポリマーそれ自体にカイラル能を有しているコレステリック液晶ポリマーそのものを用いてもよいし、ネマチック系液晶ポリマーとコレステリック系液晶ポリマーの混合物を用いてもよい。
【００９７】
例えば、液晶を呈するメソゲン基を主鎖、側鎖、あるいは主鎖及び側鎖の位置に導入した高分子、コレステリル基を側鎖に導入した高分子コレステリック液晶や、例えば、特開平９−１３３８１０号公報で開示されているような液晶性高分子、特開平１１−２９３２５２号公報で開示されているような液晶性高分子を用いる。
【００９８】
このような液晶ポリマーは、温度によって状態が変わり、例えばガラス転移温度が９０℃、アイソトロピック転移温度が２００℃である場合は、９０℃〜２００℃の間でコレステリック液晶状態を呈し、これを室温まで冷却すればコレステリック構造を保持したままガラス状態で固化させることができる。
【００９９】
尚、予め液晶ポリマーを溶媒に溶かしておいてコーティング液としてもよいが、この場合は冷却前に溶媒を蒸発させるための乾燥工程が必要となる。
【０１００】
又、コレステリック構造に起因する選択反射波長帯域を調整するためには、コレステリック液晶ポリマー分子の場合は、液晶分子中のカイラルパワーを公知の方法で調整すればよい。又、ネマチック系液晶ポリマーとコレステリック系液晶ポリマーの混合物を用いる場合は、その混合比を調整すればよい。
【０１０１】
まず、図６（Ａ）に示されるように、前述と同様に、ＴＡＣフィルム３２上に配向膜１７を形成しておく。
【０１０２】
次に、図６（Ｂ）に示されるように、配向膜１７上に、コレステリック系液晶ポリマー層５２をコーティングし、配向膜１７の配向規制力によって液晶分子を配向させる（このときコレステリック液晶層が形成される）。
【０１０３】
この状態でコレステリック系液晶ポリマー層５２を冷却して液晶分子をガラス状態に固化させれば、図６（Ｃ）に示されるように、コレステリック位相差層３４を得ることができる。
【０１０４】
尚、前述と同様に、配向膜１７の全範囲において配向規制力の方向を実質的に一致させておけば、これと接触する液晶分子のダイレクターの方向を、面内で実質的に一致させることができる。
【０１０５】
次に、ネマチック位相差層形成工程について説明する。
【０１０６】
この材料としては、ネマチック系液晶ポリマーを用いる。例えば、上記特開平１１−２９３２５２号公報で開示されているようなネマチック配向性の液晶ポリマー等を用いる。
【０１０７】
このような液晶ポリマーは、温度によって状態が変わり、所定の温度範囲でネマチック液晶状態を呈し、これを室温まで冷却すればネマチック構造を保持したままガラス状態で固化させることができる。
【０１０８】
まず、図６（Ｄ）に示されるように、ネマチック系液晶ポリマー５４を別途用意し、これをコレステリック位相差層３４の表面３４Ｂ上に直接コーティングし、該コーティングした液晶の厚さ方向の一方の表面における液晶分子のダイレクターの方向を、前記固化させたコレステリック位相差層３４の表面３４Ｂの配向規制力によって規制する。この状態で、図６（Ｅ）に示されるように、冷却して液晶分子をガラス状態に固化させ、ネマチック位相差層３６を得る。
【０１０９】
これにより、複合位相差光学素子３０が完成する。
【０１１０】
なお、上記実施の形態の例においては、ＴＡＣフィルム３２上に配向膜１７を設けたが、本発明はこれに限定されず、配向膜１７を設ける代わりに、一方の表面に実質的に配向規制力を備えたＴＡＣフィルムを使用してもよい。
【０１１１】
又、上記実施の形態の例において、いずれの場合も最初にコレステリック位相差層３４を形成し、次にネマチック位相差層３６を形成して、コレステリック位相差層３４の表面の配向規制力によりネマチック位相差層３６のダイレクターの方向を規制しているが、本発明はこれに限定されるものでなく、最初にネマチック位相差層３６を形成し、次にコレステリック位相差層３４を形成してネマチック位相差層３６の表面の配向規制力によりコレステリック位相差層３４のダイレクターの方向を規制してもよい。
【０１１２】
更に、ＴＡＣフィルム３２上に、コレステリック位相差層３４又はネマチック位相差層３６のいずれか１層のみを積層してもよい。
【０１１３】
次に、図７を参照して、本発明の液晶表示装置の実施の形態の例について説明する。
【０１１４】
この実施の形態の例に係る液晶表示装置６０は、前記図８に示される従来の液晶表示装置１００に対して、光出射側の偏光板１０２Ｂと液晶セル１０４との間に、前記実施の形態の例に係る位相差光学素子１０を配設したものである。他の構成については前記液晶表示装置１００と同様であるので説明を省略する。
【０１１５】
このように、本発明の実施形態に係る複合位相差光学素子１０で液晶セル１０４の位相差を補償することにより、液晶表示装置１００の薄型化及び低コスト化を実現しつつ、同時に、液晶セル１０４の光学特性の変化を効果的に補償することのできる。
【０１１６】
又、光学的補償の態様により、複合位相差光学素子１０を光入射側の偏光板１０２Ａと液晶セル１０４との間に配設してもよく、液晶セル１０４の両側に配設してもよい。このように複合位相差光学素子１０を液晶セル１０４の両側に配設すれば、より理想的な光学補償が可能になる。なお、液晶セル１０４の片側又は両側に位相差光学素子１０を複数配設してもよい。
【０１１７】
又、前記実施の形態の例において、液晶表示装置６０は光が厚さ方向の一方側から他方側に透過する透過型であるが、本発明はこれに限定されるものではなく、本発明に係る位相差光学素子は反射型、又は半透過型の液晶表示装置にも適用可能である。
【０１１８】
【発明の効果】
本発明によれば、薄型化及び低コスト化を実現しつつ、同時に、液晶の光学特性の変化を効果的に補償することのできる複合位相差光学素子、その製造方法及び該複合位相差光学素子を備えた液晶表示装置を提供可能である。
【図面の簡単な説明】
【図１】本発明の実施の形態の例に係る複合位相差光学素子を模式的に示す斜視図
【図２】同実施の形態の第２例に係る複合位相差光学素子を模式的に示す斜視図
【図３】同実施の形態の第３例に係る複合位相差光学素子を模式的に示す斜視図
【図４】同実施の形態の例に係る複合位相差光学素子の製造工程を示す略示断面図
【図５】同複合位相差光学素子の他の製造工程を示す略示断面図
【図６】同複合位相差光学素子の他の製造工程を示す略示断面図
【図７】本発明の実施の形態の例に係る液晶表示装置を示す略示断面図
【図８】従来の液晶表示装置を示す略示分解斜視図
【符号の説明】
１０、２０、３０、４０…複合位相差光学素子
１２、２２、３２、４２…第１位相差フィルム
１４、２４、３４、４４・・・第２位相差フィルム
３６、４６・・・第３位相差フィルム
３４Ａ、３４Ｂ、３６Ａ、３６Ｂ…表面
１７…配向膜
１７Ａ…第２の配向膜
１８、１９…重合性モノマー分子（重合性オリゴマー分子）
５２、５４…液晶ポリマー層
６０、１００…液晶表示装置
１０２Ａ、１０２Ｂ…偏光板
１０４…液晶セル[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a composite retardation optical element, a method for manufacturing the same, and a liquid crystal display device, and more particularly to a composite that can effectively compensate for a change in optical characteristics of a liquid crystal while realizing a reduction in thickness and cost. The present invention relates to a phase difference optical element, a method for manufacturing the same, and a liquid crystal display device using the composite phase difference optical element.
[0002]
[Prior art]
FIG. 8 is a perspective view showing an example of the structure of a general liquid crystal display device.
[0003]
The liquid crystal display device 100 includes a polarizing plate 102A on the incident side, a polarizing plate 102B on the emitting side, and a liquid crystal cell 104. The polarizing plates 102A and 102B are configured to selectively pass only linearly polarized light having a vibrating surface in a predetermined direction, and are disposed in a crossed Nicols shape so that the predetermined directions are perpendicular to each other. Have been. The liquid crystal cell 104 has a large number of cells, and is disposed between the polarizing plates 102A and 102B.
[0004]
For example, in the case of the VA system in which nematic liquid crystal having negative dielectric anisotropy is sealed in the liquid crystal cell 104, linearly polarized light transmitted through the polarizing plate 102A on the incident side is phase-shifted when transmitted through the driven cell. Then, the light becomes orthogonal linearly polarized light, passes through the polarizing plate 102B on the emission side, and is emitted. On the other hand, when the cell is not driven, the linearly polarized light transmitted through the polarizing plate 102A on the incident side is transmitted through the cell without being shifted in phase, and is blocked by the polarizing plate 102B on the output side. In addition, there is a liquid crystal display device configured to emit light from the polarizing plate on the emission side when the cell is not driven, and to block the light when the cell is driven. By appropriately controlling the driving voltage of the liquid crystal cell 104 for each cell, a desired image can be displayed on the polarizing plate 102B on the emission side.
[0005]
On the other hand, the liquid crystal cell 104 has birefringence, and the refractive index in the thickness direction and the refractive index in the plane direction are different. Therefore, of the linearly polarized light transmitted through the polarizing plate 102A, light incident in a direction inclined from the normal line has a phase difference when transmitted through the liquid crystal cell 104 and becomes elliptically polarized light. Note that the magnitude of the phase difference is also affected by the refractive index anisotropy of the liquid crystal molecules sealed in the liquid crystal cell 104, the cell thickness, and the wavelength of transmitted light.
[0006]
Therefore, for example, even when a certain cell is in a non-driving state and linearly polarized light is originally transmitted as it is and should be cut off by the polarizing plate 102B on the output side, a part of light transmitted in a direction inclined from the normal line is output. May leak from the polarizing plate 102B on the side.
[0007]
For this reason, the liquid crystal display device 100 has a problem of viewing angle dependency that the display quality (contrast and the like) of the image viewed from the direction inclined from the normal line is easily deteriorated with respect to the image viewed from the front. I have.
[0008]
Various techniques have been developed to improve the viewing angle dependency of such a liquid crystal display device. For example, as shown in Patent Document 1, optical compensation is performed by disposing a retardation layer having a cholesteric regular molecular structure and exhibiting birefringence between a liquid crystal cell and a polarizing plate. Has been proposed, and an example of Patent Document 1 discloses a technique in which a polymer film is formed on a glass substrate and visual angle compensation is performed by the polymer film.
[0009]
Patent Document 2 proposes an optically compensatory retardation plate in which an optically anisotropic layer made of a liquid crystal polymer is supported by a cellulose triacetate film.
[0010]
Further, Patent Document 3 proposes a method for producing a composite retardation layer film by forming a polymer liquid crystal film on a uniaxially oriented retardation film made of a thermoplastic polymer.
[0011]
[Patent Document 1]
JP-A-3-67219 (Example 2)
[0012]
[Patent Document 2]
JP 2000-155215 A
[0013]
[Patent Document 3]
JP-A-6-148429
[0014]
[Problems to be solved by the invention]
However, including the above Patent Documents 1 to 3, the conventional retardation optical element using a liquid crystal requires a separate substrate such as a glass substrate and a film when forming a retardation layer. There has been a problem that the thickness of the phase difference optical element, and eventually the liquid crystal display device as a whole, is increased and the cost is increased.
[0015]
The present invention has been made in order to solve such a problem, and a composite liquid crystal display device capable of realizing a reduction in thickness and cost while simultaneously effectively compensating for a change in optical characteristics of a liquid crystal. An object of the present invention is to provide a phase difference optical element, a method for manufacturing the same, and a liquid crystal display device including the composite phase difference optical element.
[0016]
[Means for Solving the Problems]
The present invention provides a first retardation film having a thickness that can be used as a substrate, and a normal direction set on the surface of the film is substantially an optical axis and has negative uniaxiality. A second retardation film, which is provided on the first retardation film and has a negative direction and a normal direction substantially perpendicular to the surface of the film is substantially the optical axis. The above object has been solved by using a phase difference optical element.
[0017]
According to the present invention, the first retardation film can be used not only as a retardation film for performing optical compensation, but also as a substrate, so that there is no need to prepare another substrate, and the composite retardation optics can be used. It is possible to reduce the thickness and cost of the element.
[0018]
In addition, the second retardation film may include at least one layer having a cholesteric regular liquid crystal molecular structure oriented in a planar manner and having a selective reflection wavelength of 400 nm or less.
[0019]
A first retardation film having a thickness which can be used as a base material, and a first retardation film having a thickness which can be used as a substrate; And a second retardation film having a positive in-plane direction substantially in the in-plane direction of the film and a second retardation film having a positive uniaxial property. In this case, the second retardation layer may be composed of at least one layer having a nematic regular liquid crystal molecular structure oriented in a plane.
[0020]
Further, a first retardation film having a thickness that can be used as a base material, and a first retardation film having a thickness that can be used as a base material, wherein the normal direction set on the surface of the film is substantially the optical axis and has negative uniaxiality. A second retardation film having an in-plane direction substantially equal to the optical axis and having a positive uniaxial property, and a second retardation film being provided so as to overlap the second retardation film. A third retardation film having a negative direction and a normal direction substantially perpendicular to the surface of the film, and a third retardation film having a negative uniaxial property. The retardation film may be at least one layer having an in-plane aligned nematic regular liquid crystal molecular structure, or the third retardation film may have a planarly oriented cholesteric regular liquid crystal molecular structure. And the selective reflection wavelength is 400 nm or less. Kutomo one may be a layer.
[0021]
Also, the arrangement of the retardation film may be changed, for example, the second retardation film may be provided between the first retardation film and the third retardation film, The third retardation film may be provided between the first retardation film and the second retardation film.
[0022]
The thickness of the first retardation film is preferably about 10 μm to 200 μm, and more preferably 40 μm to 100 μm.
[0023]
Further, the first retardation layer may be cellulose triacetate having an alignment regulating force by one of its surface and an alignment film provided on the surface.
[0024]
The composite retardation optical element can use a liquid crystal monomer or a liquid crystal oligomer as a material. For example, a two-layer composite retardation optical element aligns liquid crystal molecules including a polymerizable monomer or oligomer having a cholesteric regulating force. A first retardation layer in which the direction of the regulating force is substantially the same over the entire range on the film, and coating on a cellulose triacetate film having one surface substantially provided with an orientation regulating force; And a step of forming a second retardation layer having a selective reflection wavelength of 400 nm or less by three-dimensionally cross-linking the liquid crystal molecules in a state where the liquid crystal molecules are aligned by the alignment control force. A method and a first retardation layer in which liquid crystal molecules containing a polymerizable monomer or oligomer having nematic regularity are formed in a first retardation layer in which the direction of the alignment regulating force is substantially the same in the entire range on the film. A step of coating the liquid crystal molecules on a cellulose triacetate film provided with an alignment regulating force substantially on one surface, and three-dimensionally aligning the liquid crystal molecules with the alignment regulating force of the alignment film. Cross-linking to form a second retardation layer.
[0025]
Further, the three-layer composite retardation optical element has a first liquid crystal molecule including a polymerizable monomer or oligomer having nematic regularity, in which the direction of the alignment regulating force is substantially the same in the entire range on the film. A step of coating on a cellulose triacetate film which is a retardation layer and one surface of which is substantially provided with an alignment controlling force, and in which the liquid crystal molecules are aligned by the alignment controlling force of the alignment film. Forming a second retardation layer by three-dimensional cross-linking, and directly coating liquid crystal molecules containing another polymerizable monomer or oligomer having cholesteric regularity on the second retardation layer. And aligning the other liquid crystal molecules using the alignment regulating force on the surface of the three-dimensionally cross-linked second retardation layer, and then performing three-dimensional cross-linking to obtain a selective reflection wavelength of 400 nm or less. Retardation layer And a liquid crystal molecule containing a polymerizable monomer or oligomer having cholesteric regularity, wherein the direction of the alignment regulating force is substantially the same in the entire range on the film. A step of coating on a cellulose triacetate film provided with an alignment regulating force on one surface, and aligning the liquid crystal molecules by the alignment regulating force of the alignment film. A step of forming a second retardation layer having a selective reflection wavelength of 400 nm or less by three-dimensionally cross-linking in this state, and, on the second retardation layer, another polymerizable monomer having nematic regularity or A step of directly coating liquid crystal molecules including oligomers, and a step of aligning the other liquid crystal molecules using the alignment regulating force of the surface of the three-dimensionally cross-linked second retardation layer, followed by three-dimensional cross-linking. Rank By the method for producing a composite retardation optical element we characterized by comprising the steps of forming a difference layer, and can be manufactured.
[0026]
Further, the composite retardation optical element can use a liquid crystal polymer as a material. For example, in the case of a two-layer composite retardation optical element, the direction of the alignment regulating force is substantially the same over the entire range on the film. Coating a liquid crystal polymer having cholesteric regularity on a cellulose triacetate film, which is the first retardation layer, and on one surface of which is substantially provided with an alignment controlling force; and Forming a second retardation layer having a selective reflection wavelength of 400 nm or less after cooling by orienting the alignment film by the alignment regulating force of the alignment film, and then forming a second retardation layer having a selective reflection wavelength of 400 nm or less by cooling. Is the first retardation layer in which the direction is substantially the same over the entire area on the film, and a nematic film is formed on a cellulose triacetate film having one surface substantially provided with an alignment regulating force. A step of coating a liquid crystal polymer having regularity, and a step of forming the second retardation layer in a glassy state by cooling after aligning the liquid crystal polymer by an alignment regulating force of the alignment film. It can be manufactured by the following manufacturing method.
[0027]
Further, the three-layer composite retardation optical element is a first retardation layer in which the direction of the alignment regulating force is substantially the same over the entire range on the film, and has a substantially aligned direction on one surface. A step of coating a liquid crystal polymer having nematic regularity on a cellulose triacetate film provided with a regulating force, and after aligning the liquid crystal polymer by the alignment regulating force of the alignment film, cooling the glass to a glass state. Forming a second retardation layer, directly coating another liquid crystal polymer having cholesteric regularity on the second retardation layer, and forming a second liquid crystal polymer in the glass state. Forming a third retardation layer having a selective reflection wavelength of 400 nm or less after cooling by orienting the surface of the retardation layer using the alignment regulating force of step (c). On the first retardation layer in which the direction of the orientation regulating force is substantially the same over the entire range on the film, and on the cellulose triacetate film provided with the orientation regulating force on one surface. Coating a liquid crystal polymer having cholesteric regularity, and after aligning the liquid crystal polymer by the alignment regulating force of the alignment film, cooling the glass to a glass state, and a second phase difference having a selective reflection wavelength of 400 nm or less. A step of forming a layer, a step of directly coating another liquid crystal polymer having nematic regularity on the second retardation layer, and a step of forming the other liquid crystal polymer in the glass state. And forming a third retardation layer after cooling using a surface orientation regulating force to form a third retardation layer in a glassy state by cooling.
[0028]
In the above production method, an alignment film may be previously formed on the cellulose triacetate film, or a liquid crystal molecule containing the polymerizable monomer or oligomer, or the liquid crystal polymer is coated and aligned. In this case, the retardation layer may be oriented by further laminating an orientation film on the surface of another adjacent retardation layer.
[0029]
Note that the composite retardation optical element may be disposed between a liquid crystal cell and a polarizing plate to provide a liquid crystal display device that compensates for a polarization state in a direction other than the normal direction of the liquid crystal cell.
[0030]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0031]
FIG. 1 shows a composite retardation optical element 10 according to an embodiment of the present invention. The composite retardation optical element 10 includes a first retardation film (hereinafter simply referred to as a first retardation film). A first retardation film 12 and a second retardation film (hereinafter, simply referred to as a second retardation film) 14 provided on the first retardation film 12.
[0032]
The first retardation film 12 has a negative uniaxial property in which the normal direction set on the surface of the film is substantially the optical axis, and has a thickness usable as a base material. In this example, as a material of the first retardation film 12, cellulose triacetate (TAC) is used.
[0033]
Similarly, the second retardation film 14 also has a negative uniaxial property in which the normal direction set on the surface of the film is substantially the optical axis.
[0034]
That is, each of the first and second retardation films 12 and 14 has birefringence, and the refractive index in the thickness direction and the refractive index in the plane direction are different. Therefore, it is also possible to generate a phase difference between the linearly polarized light in the direction inclined from the normal line and make it into elliptically polarized light, and conversely to convert the elliptically polarized light in the direction inclined from the normal line into linearly polarized light. It should be noted that the linearly polarized light transmitted in the normal direction is directly transmitted as linearly polarized light without causing a phase difference.
[0035]
The second retardation film 14 has a cholesteric regular liquid crystal molecular structure oriented in a planar manner, and has a selective reflection wavelength of 400 nm or less.
[0036]
Here, the term “liquid crystal molecule” is generally used in the sense of a molecule having both the fluidity of liquid and the anisotropy of crystals. For the sake of convenience, the term “liquid crystal molecule” is also used for a molecule that has been solidified while maintaining the anisotropy from the state of having.
[0037]
The reason why the selective reflection wavelength of the second retardation film (cholesteric retardation film) 14 is 400 nm or less is to prevent coloring due to selective reflection due to the helical structure of liquid crystal molecules.
[0038]
Hereinafter, the selective reflection wavelength of the second retardation film 14 will be briefly described.
[0039]
A retardation film having cholesteric regularity generally has a property of selectively reflecting one of two circularly polarized lights, right-handed and left-handed, of natural light incident along a helical axis of a liquid crystal planar arrangement. ing.
[0040]
This phenomenon is known as circular dichroism, and when the direction of rotation in the helical structure of the liquid crystal molecules is appropriately selected, circularly polarized light having the same optical rotation direction as the direction of rotation is selectively reflected.
[0041]
In this case, the maximum rotatory polarized light scattering occurs at the selected wavelength λ0 in the following equation (1).
[0042]
λ0 = nav · p (1)
p is the helical pitch in the helical structure of the liquid crystal molecules, and nav is the average refractive index in a plane perpendicular to the helical axis.
[0043]
Δλ = Δn · p (2)
Δλ is the wavelength bandwidth, and Δn is the birefringence value.
[0044]
That is, the retardation film having cholesteric regularity reflects one of the right-handed or left-handed circularly polarized light components of light in the range of the wavelength bandwidth Δλ centered on the selected wavelength λ0, and the other circularly polarized light component and the other. Transmits light in the wavelength region (unpolarized light). It should be noted that the reflected right-handed or left-handed circularly polarized light is reflected without any phase inversion, unlike ordinary reflection.
[0045]
Since the wavelength band of visible light is about 400 to 800 nm, by configuring the second retardation film 14 so that the selective reflection wavelength is 400 nm or less, coloring due to visible light reflection can be prevented, and In addition, a phase shift effect can be exerted on light obliquely incident on the helical axis.
[0046]
Thus, by using the two first and second retardation films 12 and 14 together, it is possible to effectively compensate for the change in the optical characteristics of the liquid crystal.
[0047]
Moreover, since the first retardation film 12 can be used not only as a retardation film for performing optical compensation but also as a substrate, there is no need to prepare another substrate, and the first retardation film It is possible to reduce the thickness and cost.
[0048]
In order to obtain a higher effect, the thickness of the first retardation film 12 is preferably about 10 μm to 200 μm, and more preferably 40 μm to 100 μm.
[0049]
Next, a composite retardation optical element 20 according to a second example of the embodiment of the present invention will be described with reference to FIG.
[0050]
The composite retardation optical element 20 includes a first retardation film 22 and a second retardation film 24 provided on the first retardation film 22.
[0051]
The first retardation film 22 is the same as the first retardation film 12 of the composite retardation optical element 10, and the normal direction set on the surface of the film is substantially the optical axis and the negative uniaxial And has a thickness that can be used as a substrate.
[0052]
On the other hand, the second retardation film 24 has a liquid crystal molecular structure of nematic regularity, and is a film having a positive uniaxial property in which the in-plane direction of the film is substantially the optical axis.
[0053]
That is, the second retardation film (nematic retardation film) 24 has birefringence, but the refractive index in the direction of the director is different from the refractive index in the direction perpendicular to the director. Therefore, even in the direction along the surface, the refractive index in the direction of the director is different from the refractive index in the direction perpendicular to the director. The refractive index in the direction perpendicular to the director along the surface is equal to the refractive index in the thickness direction.
[0054]
As described above, the same effect as that of the composite retardation optical element 10 can be obtained by using the first and second retardation films 22 and 24 having different birefringence modes in directions.
[0055]
Next, a composite retardation optical element 30 according to a third embodiment of the present invention will be described with reference to FIG.
[0056]
FIG. 3A shows a composite retardation optical element 30 according to a third example of the embodiment of the present invention. The composite retardation optical element 30 includes a first retardation film 32 and a first retardation film 32. A second retardation film 34 provided on the first retardation film 32, and a third retardation film (hereinafter simply referred to as a third retardation film) provided on the second retardation film 34. 36).
[0057]
The first retardation film 32 is the first retardation film 12 (22), and the second retardation film 34 is the third retardation film 14 with the second retardation film 14 of the composite retardation optical element 10. The film 36 is the same as the second retardation film of the composite retardation optical element 20, respectively, and the description is omitted.
[0058]
Thus, the optical compensation effect can be further enhanced by using the first, second, and third retardation films 32, 34, and 36 in combination.
[0059]
In the composite retardation optical element 30 according to the third example of the above embodiment, the second retardation film 34 is a cholesteric retardation film, and the third retardation film 36 is a nematic retardation film. Is not limited to this. Therefore, for example, as shown in FIG. 3B, the second retardation film 44 may be a nematic retardation film, and the third retardation film 46 may be a cholesteric retardation film. Further, the first to third retardation films may have another liquid crystal molecular structure.
[0060]
Next, the material and manufacturing method of the cholesteric retardation layer 34 and the nematic retardation layer 36 using the composite retardation optical element 30 will be described.
[0061]
The cholesteric retardation layer 34 and the nematic retardation layer 36 can be manufactured by three-dimensionally cross-linking using a liquid crystal monomer or a liquid crystal oligomer as a material, or solidifying to a glass state using a liquid crystal polymer as a material. .
[0062]
Here, three-dimensional crosslinking means that polymerizable monomer or oligomer molecules are three-dimensionally polymerized with each other to form a network structure. In such a state, the liquid crystal molecules can be optically fixed while maintaining the cholesteric structure and the nematic structure, and can be configured as a film-shaped optical film that is stable at room temperature. Can be improved.
[0063]
First, a case where a liquid crystalline monomer or a liquid crystalline oligomer is used as a material of the retardation layer will be described.
[0064]
When a polymerizable monomer molecule (or a polymerizable oligomer molecule) is converted into a liquid crystal phase at a predetermined temperature, a nematic liquid crystal is formed. When an arbitrary chiral agent is added thereto, a chiral nematic liquid crystal (cholesteric liquid crystal) is obtained.
[0065]
The polymerizable monomer molecule (or polymerizable oligomer molecule) may be a coating solution dissolved in a solvent. In this case, the solvent is evaporated before irradiation with ultraviolet rays or electron beams to cause three-dimensional crosslinking. Requires a drying step.
[0066]
Examples of three-dimensionally crosslinkable monomer molecules include a mixture of a liquid crystalline monomer and a chiral compound as disclosed in, for example, JP-A-7-258538 and JP-T-10-508882. More specifically, for example, liquid crystalline monomers represented by general chemical formulas (1) to (11) can be used. In the case of the liquid crystalline monomer represented by the general chemical formula (11), X is desirably 2 to 5 (integer).
[0067]
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[0068]
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[0069]
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[0070]
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[0071]
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[0072]
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[0073]
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[0074]
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[0075]
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[0076]
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[0077]
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[0078]
Further, as the chiral agent, for example, chiral agents represented by general chemical formulas (12) to (14) can be used. In the case of the chiral agent represented by the general chemical formulas (12) and (13), X is desirably 2 to 12 (integer). In the case of the chiral agent represented by the general chemical formula (14), X is preferably It is desirably 2 to 5 (integer).
[0079]
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[0080]
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[0081]
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[0082]
When an oligomer molecule is used, a cyclic organopolysiloxane compound having a cholesteric phase as disclosed in JP-A-57-165480 is desirable.
[0083]
First, the cholesteric retardation layer forming step will be described.
[0084]
In the example of this embodiment, a cholesteric liquid crystal is obtained by adding about several to 10% of a chiral agent to a polymerizable monomer molecule or a polymerizable oligomer molecule. The selective reflection wavelength band of the cholesteric liquid crystal can be adjusted by changing the chiral power by changing the type of the chiral agent or by changing the concentration of the chiral agent.
[0085]
First, as shown in FIG. 4A, an alignment film 17 is formed on a TAC film 32, and a polymerizable monomer molecule (or a polymerizable monomer molecule) is formed thereon as shown in FIG. The polymerizable monomer molecules 18 are coated and aligned by the alignment controlling force of the alignment film 17 (at this time, the coated polymerizable monomer molecules and the like constitute a cholesteric liquid crystal layer). When a solvent is contained in the coating liquid, a drying step for removing the solvent is included after the coating step. In the TAC film 32, the direction of the alignment regulating force is substantially the same in the entire range on the film.
[0086]
Next, in the above-mentioned orientation state, as shown in FIG. 4C, a polymerizable monomer molecule (or polymerizable oligomer molecule) 18 is added to a photo-initiator added in advance and ultraviolet light irradiated from the outside. The cholesteric retardation layer 34 is obtained by initiating polymerization or by directly initiating polymerization with an electron beam and performing three-dimensional crosslinking (polymerization).
[0087]
If the direction of the alignment regulating force of the alignment film 17 is made substantially coincident with the entire range of the alignment film 17, the direction of the director of the liquid crystal molecules on the surface 34 A on the side in contact with the alignment film 17 will be changed. Can be substantially matched within.
[0088]
Note that the alignment film 17 is formed by a conventionally known method. For example, as described above, a method of forming a film of PI (polyimide) or PVA (polyvinyl alcohol) on the TAC film 32 and performing rubbing, a method of forming a polymer compound to be a photo-alignment film on the TAC film 32, (Ultraviolet light), a method using a stretched film of PET (polyethylene terephthalate) or the like.
[0089]
Next, a nematic retardation layer forming step will be described.
[0090]
First, as shown in FIG. 4 (D), a polymerizable monomer molecule (or polymerizable oligomer molecule) 19 having a nematic liquid crystal phase at a predetermined temperature is separately prepared, and this is provided on the cholesteric retardation layer 34. And the direction of the director of the liquid crystal molecules on one surface in the thickness direction of the coated liquid crystal is regulated by the alignment regulating force on the surface of the three-dimensionally crosslinked cholesteric retardation layer 34 (at this time, And the coated polymerizable monomer molecules and the like constitute a nematic liquid crystal layer). In this state, as shown in FIG. 4E, the nematic retardation layer 36 is obtained by three-dimensionally cross-linking and solidifying by the same ultraviolet irradiation or electron beam irradiation as described above. When a solvent is contained in the coating liquid, a drying step for removing the solvent is included after the coating step.
[0091]
Thereby, the composite retardation optical element 30 is completed.
[0092]
According to the method for manufacturing the composite retardation optical element 30 according to the example of the embodiment of the present invention, the manufacture of the composite retardation optical element 30 becomes easy. In addition, since the liquid crystal molecules of the third retardation film 36 can be aligned using the alignment regulating force of the surface 34B of the second retardation film 34, the productivity can be improved. If the alignment regulating force of the surface 34B itself is weak, rubbing may be performed.
[0093]
In addition, as shown in FIG. 5, even if the nematic retardation layer 36 is oriented by further laminating the orientation film 17A on the surface 34B of the cholesteric retardation film 34 adjacent to the nematic retardation film 36, Similar effects can be obtained.
[0094]
Next, a case where a polymer (polymer) liquid crystal is used as a material of the retardation layer will be described with reference to FIG.
[0095]
First, the cholesteric retardation layer forming step will be described.
[0096]
As this material, a cholesteric liquid crystal polymer itself having a chiral ability in the liquid crystal polymer itself may be used, or a mixture of a nematic liquid crystal polymer and a cholesteric liquid crystal polymer may be used.
[0097]
For example, a polymer having a mesogen group presenting a liquid crystal in a main chain, a side chain, or a position of a main chain and a side chain, a polymer cholesteric liquid crystal in which a cholesteryl group is introduced in a side chain, and, for example, JP-A-9-133810 A liquid crystalline polymer disclosed in the official gazette and a liquid crystalline polymer disclosed in Japanese Patent Application Laid-Open No. 11-293252 are used.
[0098]
Such a liquid crystal polymer changes its state depending on the temperature. For example, when the glass transition temperature is 90 ° C. and the isotropic transition temperature is 200 ° C., the liquid crystal polymer exhibits a cholesteric liquid crystal state between 90 ° C. and 200 ° C. If cooled down, it can be solidified in a glassy state while maintaining the cholesteric structure.
[0099]
The coating liquid may be prepared by dissolving the liquid crystal polymer in a solvent in advance, but in this case, a drying step for evaporating the solvent before cooling is required.
[0100]
In order to adjust the selective reflection wavelength band caused by the cholesteric structure, in the case of a cholesteric liquid crystal polymer molecule, the chiral power in the liquid crystal molecule may be adjusted by a known method. When a mixture of a nematic liquid crystal polymer and a cholesteric liquid crystal polymer is used, the mixing ratio may be adjusted.
[0101]
First, as shown in FIG. 6A, the alignment film 17 is formed on the TAC film 32 in the same manner as described above.
[0102]
Next, as shown in FIG. 6B, a cholesteric liquid crystal polymer layer 52 is coated on the alignment film 17 and liquid crystal molecules are aligned by the alignment control force of the alignment film 17 (at this time, the cholesteric liquid crystal layer It is formed).
[0103]
In this state, if the cholesteric liquid crystal polymer layer 52 is cooled to solidify the liquid crystal molecules into a glass state, a cholesteric retardation layer 34 can be obtained as shown in FIG.
[0104]
As described above, if the direction of the alignment regulating force is substantially matched in the entire range of the alignment film 17, the direction of the director of the liquid crystal molecules in contact with the direction is substantially matched in the plane. be able to.
[0105]
Next, a nematic retardation layer forming step will be described.
[0106]
As this material, a nematic liquid crystal polymer is used. For example, a nematic alignment liquid crystal polymer or the like as disclosed in the above-mentioned JP-A-11-293252 is used.
[0107]
Such a liquid crystal polymer changes its state depending on the temperature, and exhibits a nematic liquid crystal state within a predetermined temperature range. When the liquid crystal polymer is cooled to room temperature, it can be solidified in a glass state while maintaining a nematic structure.
[0108]
First, as shown in FIG. 6 (D), a nematic liquid crystal polymer 54 is separately prepared, and this is directly coated on the surface 34B of the cholesteric retardation layer 34, and one side in the thickness direction of the coated liquid crystal. The direction of the director of the liquid crystal molecules on the surface is regulated by the orientation regulating force of the surface 34B of the solidified cholesteric retardation layer 34. In this state, as shown in FIG. 6 (E), the liquid crystal molecules are cooled to solidify into a glass state, and a nematic retardation layer 36 is obtained.
[0109]
Thereby, the composite retardation optical element 30 is completed.
[0110]
Although the alignment film 17 is provided on the TAC film 32 in the above-described embodiment, the present invention is not limited to this. A TAC film with force may be used.
[0111]
In each of the above embodiments, the cholesteric retardation layer 34 is formed first, then the nematic retardation layer 36 is formed, and the nematic phase is controlled by the alignment control force on the surface of the cholesteric retardation layer 34. Although the direction of the director of the retardation layer 36 is regulated, the present invention is not limited to this. First, the nematic retardation layer 36 is formed, and then the cholesteric retardation layer 34 is formed. The direction of the director of the cholesteric retardation layer 34 may be regulated by the orientation regulating force on the surface of the nematic retardation layer 36.
[0112]
Further, only one of the cholesteric retardation layer 34 and the nematic retardation layer 36 may be laminated on the TAC film 32.
[0113]
Next, an example of an embodiment of the liquid crystal display device of the present invention will be described with reference to FIG.
[0114]
The liquid crystal display device 60 according to this embodiment is different from the conventional liquid crystal display device 100 shown in FIG. 8 in that a liquid crystal cell 104 is provided between the polarizing plate 102B on the light emission side and the liquid crystal cell 104. In this example, the phase difference optical element 10 according to the example is disposed. The other configuration is the same as that of the liquid crystal display device 100, and the description is omitted.
[0115]
As described above, by compensating for the phase difference of the liquid crystal cell 104 with the composite retardation optical element 10 according to the embodiment of the present invention, the liquid crystal display device 100 can be made thinner and lower in cost, and It is possible to effectively compensate for the change in the optical characteristics of the optical device 104.
[0116]
Further, depending on the mode of optical compensation, the composite retardation optical element 10 may be disposed between the polarizing plate 102A on the light incident side and the liquid crystal cell 104, or may be disposed on both sides of the liquid crystal cell 104. . By arranging the composite retardation optical element 10 on both sides of the liquid crystal cell 104, more ideal optical compensation is possible. Note that a plurality of retardation optical elements 10 may be provided on one side or both sides of the liquid crystal cell 104.
[0117]
Further, in the example of the above-described embodiment, the liquid crystal display device 60 is of a transmission type in which light is transmitted from one side in the thickness direction to the other side, but the present invention is not limited to this. Such a phase difference optical element can also be applied to a reflective or transflective liquid crystal display device.
[0118]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, while realizing thickness reduction and cost reduction, while simultaneously compensating the change of the optical characteristic of a liquid crystal effectively, the composite phase difference optical element, its manufacturing method, and this composite phase difference optical element Can be provided.
[Brief description of the drawings]
FIG. 1 is a perspective view schematically showing a composite retardation optical element according to an embodiment of the present invention.
FIG. 2 is a perspective view schematically showing a composite retardation optical element according to a second example of the embodiment.
FIG. 3 is a perspective view schematically showing a composite retardation optical element according to a third example of the embodiment.
FIG. 4 is a schematic sectional view showing a manufacturing process of the composite retardation optical element according to the example of the embodiment.
FIG. 5 is a schematic sectional view showing another manufacturing process of the composite retardation optical element.
FIG. 6 is a schematic sectional view showing another manufacturing process of the composite retardation optical element.
FIG. 7 is a schematic cross-sectional view showing a liquid crystal display device according to an example of an embodiment of the present invention.
FIG. 8 is a schematic exploded perspective view showing a conventional liquid crystal display device.
[Explanation of symbols]
10, 20, 30, 40 ... composite retardation optical element
12, 22, 32, 42 ... first retardation film
14, 24, 34, 44 ... second retardation film
36, 46: Third retardation film
34A, 34B, 36A, 36B ... surface
17 ... Orientation film
17A: Second alignment film
18, 19: polymerizable monomer molecule (polymerizable oligomer molecule)
52, 54: Liquid crystal polymer layer
60, 100: Liquid crystal display device
102A, 102B ... Polarizing plate
104: liquid crystal cell

Claims (23)

A first retardation film having a thickness substantially normal to the optical axis, having a negative uniaxial property, and usable as a substrate, A second retardation film provided so as to be superimposed on the retardation film, the normal direction standing on the surface of the film being substantially the optical axis, and having a negative uniaxial property. Phase difference optical element. In claim 1,
The composite retardation optical element, wherein the second retardation film has at least one layer having a planar-aligned cholesteric regular liquid crystal molecular structure and a selective reflection wavelength of 400 nm or less. . A first retardation film having a thickness substantially normal to the optical axis, having a negative uniaxial property, and usable as a substrate, A composite retardation optical element comprising: a second retardation film provided so as to overlap the retardation film, wherein the in-plane direction of the film is substantially the optical axis and has positive uniaxiality. . In claim 3,
The composite retardation optical element, wherein the second retardation film comprises at least one layer having a nematic regular liquid crystal molecular structure oriented in a plane. A first retardation film having a thickness substantially normal to the optical axis, having a negative uniaxial property, and usable as a substrate, A second retardation film having a positive uniaxial property in which the in-plane direction of the film is substantially the optical axis and provided on the phase difference film; And a third retardation film having a negative uniaxial property with a normal direction substantially perpendicular to the surface of the third retardation film. In claim 5,
The composite retardation optical element, wherein the second retardation film comprises at least one layer having a nematic regular liquid crystal molecular structure oriented in a plane. In claim 5 or 6,
The composite retardation optical element, wherein the third retardation film has at least one layer having a planar-aligned cholesteric regular liquid crystal molecular structure and a selective reflection wavelength of 400 nm or less. . In any one of claims 5 to 7,
A composite retardation optical element, wherein the second retardation film is provided between the first retardation film and the third retardation film. In any one of claims 5 to 7,
A composite retardation optical element, wherein the third retardation film is provided between the first retardation film and the second retardation film. In any one of claims 1 to 9,
A composite retardation optical element, wherein the thickness of the first retardation film is about 10 μm to 200 μm. In any one of claims 1 to 10,
The composite retardation optical element, wherein the first retardation layer is made of cellulose triacetate having an alignment regulating force by one of a surface thereof and an alignment film provided on the surface. A liquid crystal molecule containing a polymerizable monomer or oligomer having a cholesteric regulating force is a first retardation layer in which the direction of the orientation regulating force is substantially the same over the entire range on the film, and on one surface. A step of coating on a cellulose triacetate film substantially provided with an alignment controlling force, and three-dimensionally cross-linking the liquid crystal molecules in a state where the liquid crystal molecules are aligned by the alignment controlling force, and the selective reflection wavelength is 400 nm or less. Forming a second retardation layer. A method for producing a composite retardation optical element, comprising: A liquid crystal molecule containing a polymerizable monomer or oligomer having nematic regularity is the first retardation layer in which the direction of the alignment regulating force is substantially the same over the entire range on the film, and has one surface. A step of coating on a cellulose triacetate film substantially provided with an alignment regulating force, and three-dimensionally cross-linking the liquid crystal molecules in a state where the liquid crystal molecules are aligned by the alignment regulating force of the alignment film, and a second retardation Forming a layer. A method for producing a composite retardation optical element, comprising: A liquid crystal molecule containing a polymerizable monomer or oligomer having nematic regularity is the first retardation layer in which the direction of the alignment regulating force is substantially the same over the entire range on the film, and has one surface. A step of coating on a cellulose triacetate film substantially provided with an alignment regulating force, and three-dimensionally cross-linking the liquid crystal molecules in a state where the liquid crystal molecules are aligned by the alignment regulating force of the alignment film, thereby forming a second retardation. Forming a layer, directly coating the second retardation layer with liquid crystal molecules having a cholesteric regularity and containing another polymerizable monomer or oligomer, and applying the other liquid crystal molecules to the second retardation layer. Forming a third retardation layer having a selective reflection wavelength of 400 nm or less by subjecting the two-dimensionally crosslinked second retardation layer surface to orientation using the alignment regulating force, and then performing three-dimensional crosslinking. To become a The method of producing a composite retardation optical element characterized. A liquid crystal molecule containing a polymerizable monomer or oligomer having cholesteric regularity is the first retardation layer in which the direction of the alignment regulating force is substantially the same over the entire range on the film, and has one surface. A step of coating on a cellulose triacetate film substantially provided with an alignment controlling force, and three-dimensionally cross-linking the liquid crystal molecules in a state where the liquid crystal molecules are aligned by the alignment controlling force of the alignment film to have a selective reflection wavelength of 400 nm. A step of forming a second retardation layer, and a step of directly coating liquid crystal molecules including another polymerizable monomer or oligomer having nematic regularity on the second retardation layer, Aligning another liquid crystal molecule using the alignment regulating force of the surface of the three-dimensionally cross-linked second retardation layer, and then three-dimensionally cross-linking to form a third retardation layer. To become a The method of producing a composite retardation optical element characterized. On the first retardation layer in which the direction of the orientation regulating force is substantially the same over the entire range on the film, and on the cellulose triacetate film provided with the orientation regulating force on one surface. Coating a liquid crystal polymer having cholesteric regularity, and after aligning the liquid crystal polymer by the alignment regulating force of the alignment film, cooling the glass to a glass state, and a second phase difference having a selective reflection wavelength of 400 nm or less. Forming a layer. A method for producing a composite retardation optical element, comprising: On the first retardation layer in which the direction of the orientation regulating force is substantially the same over the entire range on the film, and on the cellulose triacetate film provided with the orientation regulating force on one surface. A step of coating a liquid crystal polymer having nematic regularity, and a step of aligning the liquid crystal polymer by the alignment regulating force of the alignment film, and then cooling the glass to a glass state to form a second retardation layer. A method for producing a composite retardation optical element, comprising: On the first retardation layer in which the direction of the orientation regulating force is substantially the same over the entire range on the film, and on the cellulose triacetate film provided with the orientation regulating force on one surface. A step of coating a liquid crystal polymer having nematic regularity, a step of aligning the liquid crystal polymer by an alignment regulating force of the alignment film, and then forming a second retardation layer in a glassy state by cooling. A step of directly coating another liquid crystal polymer having cholesteric regularity on the second retardation layer, and using the alignment regulating force of the surface of the second retardation layer in which the other liquid crystal polymer is in the glassy state. Forming a third retardation layer having a selective reflection wavelength of 400 nm or less after cooling after being oriented to a glass state by cooling. . On the first retardation layer in which the direction of the orientation regulating force is substantially the same over the entire range on the film, and on the cellulose triacetate film provided with the orientation regulating force on one surface. Coating a liquid crystal polymer having cholesteric regularity, and after aligning the liquid crystal polymer by the alignment regulating force of the alignment film, cooling the glass to a glass state, and a second phase difference having a selective reflection wavelength of 400 nm or less. A step of forming a layer, a step of directly coating another liquid crystal polymer having nematic regularity on the second retardation layer, and a step of forming the other liquid crystal polymer in the glass state. Forming a third retardation layer in a glassy state by cooling after orienting using a surface orientation regulating force, and forming a third retardation layer by cooling. . In any one of claims 12 to 19,
A method for manufacturing a composite retardation optical element, comprising forming an alignment film on the cellulose triacetate film in advance. In any one of claims 12 to 15,
When coating and aligning liquid crystal molecules containing the polymerizable monomer or oligomer, the alignment of the retardation layer is performed by further stacking an alignment film on the surface of another adjacent retardation layer. Of manufacturing a composite retardation optical element. In any one of claims 16 to 19,
When the liquid crystal polymer is coated and aligned, the alignment of the retardation layer is performed by further laminating an alignment film on the surface of another adjacent retardation layer, wherein the composite retardation optical element is characterized in that: Manufacturing method. 23. The composite retardation optical element according to claim 1, which is disposed between a liquid crystal cell and a polarizing plate to compensate for a polarization state in a direction other than a normal direction of the liquid crystal cell. Liquid crystal display.

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