JPWO2010126110A1 - Wire grid polarizer and method of manufacturing the same - Google Patents

Abstract

Provided are a wire grid polarizer having a high degree of polarization and a high p-polarized light transmittance and a low back surface s-polarized light reflectance, and a method for producing the same. Light transmission in which a plurality of ridges 12 whose width gradually narrows from the bottom to the top is formed on the surface in parallel with each other and at a predetermined pitch Pp through flat portions 13 formed between the ridges 12. Between the projecting substrate 14, the first reflective layer 20 made of a metal material covering the first side surface 16 of the ridge 12, and between the ridge 12 and the first reflective layer 20. A wire grid polarizer 10 having a first absorption layer 22 made of a light-absorbing material that absorbs light rather than a metal material, covering the entire surface of the first side surface 16 of the first side surface 16; A method of manufacturing a wire grid polarizer 10 that forms one absorption layer 22 and a first reflective layer 20, and a liquid crystal display device including the wire grid polarizer 10.

Description

  The present invention relates to a wire grid polarizer and a manufacturing method thereof.

As a polarizer (also referred to as a polarization separation element) having polarization separation ability in a visible light region, which is used in an image display device such as a liquid crystal display device, a rear projection television, or a front projector, an absorption polarizer and a reflection polarizer There is.
The absorptive polarizer is, for example, a polarizer in which a dichroic dye such as iodine is oriented in a resin film. However, since the absorption polarizer absorbs one polarized light, the light use efficiency is low.

On the other hand, the reflective polarizer can increase the light utilization efficiency by allowing the reflected light to reenter the polarizer without entering the polarizer. Therefore, the need for a reflective polarizer is increasing for the purpose of increasing the brightness of liquid crystal display devices and the like.
Examples of the reflective polarizer include a linear polarizer made of a birefringent resin laminate, a circular polarizer made of cholesteric liquid crystal, and a wire grid polarizer.
However, linear polarizers and circular polarizers have low polarization separation ability. For this reason, wire grid polarizers exhibiting high polarization separation ability have attracted attention.

  The wire grid polarizer has a structure in which a plurality of fine metal wires are arranged in parallel to each other on a light-transmitting substrate. When the pitch of the fine metal wires is sufficiently shorter than the wavelength of the incident light, the light incident from the side on which the ridges of the wire grid polarizer are formed (hereinafter referred to as the surface side) is orthogonal to the fine metal wires. A component having an electric field vector (ie, p-polarized light) is transmitted, and a component having an electric field vector parallel to the metal wire (ie, s-polarized light) is reflected.

The following are known as wire grid polarizers that exhibit polarization separation in the visible light region.
(1) A wire grid type polarizer in which a metal layer is formed on a plurality of protrusions formed at a predetermined pitch on the surface of a light-transmitting substrate to form a thin metal wire (Patent Documents 1 and 2).

  The wire grid polarizer of (1) has good productivity because it forms fine metal wires by metal deposition. However, when the wire grid polarizer of (1) is attached to the backlight side surface of the liquid crystal panel of the liquid crystal display device, the liquid crystal panel side (the side on which the protrusions of the wire grid polarizer are not formed). Hereinafter, the s-polarized light incident from the back surface side is reflected by the thin metal wire, and the contrast of the displayed image is lowered.

The following have been proposed as wire grid polarizers in which the reflectance of s-polarized light incident from the back surface side (hereinafter referred to as back surface s-polarized reflectance) is suppressed.
(2) A wire grid polarizer in which a black layer and a metal layer are formed on top of a plurality of protrusions having a rectangular cross section formed on the surface of a light-transmitting substrate at a predetermined pitch (FIG. 28 (a) of Patent Document 3) (B)).

JP 2006-003447 A International Publication No. 2006/064693 Pamphlet (US Publication 2008/0129931) International Publication No. 2008/084856 Pamphlet

However, the wire grid polarizer of (2) (a) has the following problems.
(I) Since the cross-sectional shape of the ridge is rectangular and the L-shaped metal layer is formed on the rectangular ridge, the p-polarized light transmittance is low, and the luminance of the displayed image is lowered.
(Ii) Since the black layer is formed only on the top of the ridge, the back surface s-polarized reflectance is not sufficiently suppressed, and the contrast of the displayed image is lowered.
(Iii) To obtain the effect of suppressing the back surface s-polarized reflectance, the black layer side needs to be attached to the liquid crystal panel. However, since the black layer side is uneven, the wire grid polarizer is applied to the liquid crystal panel. Difficult to paste. Moreover, there is a possibility that the optical characteristics are deteriorated due to the influence of the glue used at the time of pasting.
(Iv) Since light from the backlight is incident from the light transmissive substrate side, p-polarized light is reflected at the interface between air and the light transmissive substrate, and the brightness of the displayed image is lowered.

Further, the wire grid polarizer (2) (b) has the following problems.
(I) Since the cross-sectional shape of the ridge is rectangular and the L-shaped metal layer is formed on the rectangular ridge, the p-polarized light transmittance is low, and the luminance of the displayed image is lowered.
(Ii) Since the metal layer is formed only on the top of the ridge, the degree of polarization is low.
(Iii) Since the black layer does not completely cover one side surface of the ridge, the back surface s-polarized reflectance is not sufficiently suppressed, and the contrast of the displayed image is lowered.

  The present invention provides a wire grid polarizer having a high degree of polarization and p-polarized light transmittance and a low back surface s-polarized light reflectance, and a method for producing the same.

  In the wire grid polarizer of the present invention, a plurality of ridges whose width gradually decreases from the bottom to the top are parallel to each other through a flat portion formed between the ridges and have a predetermined pitch. A light-transmitting substrate formed on the surface, a first reflective layer made of a metal material covering the first side surface of the ridge, the first side surface of the ridge and the first reflective layer And a first absorption layer made of a light-absorbing material that absorbs light more than the metal material, covering the entire first side surface of the ridge.

The thickness of the first absorption layer is preferably 3 to 20 nm.
The wire grid polarizer of the present invention is made of a metal material that exists between the first side surface of the ridge and the first absorption layer and covers the entire surface of the first side surface of the ridge. It is preferable to further have an underlayer.
The wire grid polarizer of the present invention preferably further includes a second absorption layer made of the light absorbing material that covers the entire surface of the second side surface of the ridge.
It is preferable that the wire grid polarizer of the present invention further includes a second reflective layer made of a metal material that covers the surface of the second absorption layer.
The cross-sectional shape perpendicular to the length direction of the ridge is preferably a triangle or a trapezoid.
The pitch Pp is preferably 300 nm or less.

  In the method of manufacturing the wire grid polarizer of the present invention, the plurality of ridges whose width gradually decreases from the bottom to the top are parallel to each other via the flat portion formed between the ridges, and A light-transmitting substrate formed on the surface at a predetermined pitch, a first reflective layer made of a metal material covering the first side surface of the ridge, the first side surface of the ridge and the first And a first absorption layer made of a light-absorbing material that absorbs light rather than the metal material, which is present between the reflective layer and covers the entire first side surface of the ridge. A method of manufacturing a polarizer, wherein the polarizer is substantially orthogonal to the length direction of the ridges and forms an angle of 25 to 40 ° on the first side surface side with respect to the height direction of the ridges. The light-absorbing material is vapor-deposited from the direction under the condition that the vapor deposition amount is 3 to 20 nm. Forming the collecting layer, substantially perpendicular to the length direction of the ridges, and from a direction that forms an angle of 25 to 50 ° to the first side surface with respect to the height direction of the ridges. The material is vapor-deposited under the condition that the vapor deposition amount is 15 to 50 nm to form the first reflective layer.

The cross-sectional shape perpendicular to the length direction of the ridge is preferably a triangle or a trapezoid.
The ridges are preferably made of a photo-curing resin or a thermoplastic resin and formed by an imprint method.

  In the liquid crystal display device of the present invention, a liquid crystal panel having a liquid crystal layer sandwiched between a pair of substrates, a backlight unit, and a surface on which the protrusions are formed are on the backlight unit side, and the protrusions are formed. The wire grid polarizer according to the present invention is arranged so that the surface on the side that is not provided is the viewing side of the liquid crystal display device.

The liquid crystal display device of the present invention further includes an absorption polarizer, the wire grid polarizer is disposed on one surface of the liquid crystal panel, and the absorption polarizer is the wire grid polarizer. It is preferable to be disposed on the surface of the liquid crystal panel opposite to the disposed side.
The wire grid polarizer is disposed on the surface of the liquid crystal panel on the backlight unit side, and the absorption polarizer is disposed on the surface of the liquid crystal panel on the side opposite to the backlight unit side. More preferably.

The liquid crystal display device of the present invention further includes an absorptive polarizer, the wire grid polarizer is integrated with one of the pair of substrates of the liquid crystal panel, and the absorptive polarizer is It is preferable that the liquid crystal panel is disposed on the surface of the liquid crystal panel opposite to the side on which the wire grid polarizer is integrated.
Further, the wire grid polarizer is integrated with the substrate of the liquid crystal panel on the backlight unit side, and the absorption polarizer is formed on the surface of the liquid crystal panel on the side opposite to the backlight unit side. More preferably, they are arranged.

The liquid crystal display device of the present invention further includes an absorptive polarizer, and the wire grid polarizer is disposed on the liquid crystal layer side of one of the pair of substrates of the liquid crystal panel, and the absorptive type It is preferable that the polarizer is disposed on the surface of the substrate of the liquid crystal panel opposite to the side on which the wire grid polarizer is disposed.
The wire grid polarizer is disposed on the liquid crystal layer side of the backlight unit side substrate of the pair of substrates of the liquid crystal panel, and the absorption polarizer is the backlight unit side. More preferably, it is disposed on the surface of the liquid crystal panel on the opposite side.

The wire grid polarizer of the present invention has a high degree of polarization and p-polarized light transmittance, and a low back surface s-polarized light reflectance. Moreover, since the back surface side can be affixed to a liquid crystal panel, it is easy to affix a wire grid type polarizer to a liquid crystal panel. Furthermore, since light from the backlight is incident from the surface side, reflection of p-polarized light at the interface can be suppressed.
According to the method for manufacturing a wire grid polarizer of the present invention, a wire grid polarizer having a high degree of polarization and p-polarized light transmittance and a low back surface s-polarized light reflectance can be manufactured with high productivity.
In particular, according to a preferred embodiment of the present invention, high p-polarized light transmittance of 35% or more, more preferably 38% or more, most preferably 40% or more at wavelengths of 450 nm, 550 nm, and 700 nm, and 35% or more at each wavelength. A wire grid polarizer having a high front surface s-polarized reflectance, a lower back surface s-polarized reflectance of less than 20% at the same wavelength, and a degree of polarization of 99.2% or more can be obtained.
The liquid crystal display device of the present invention has high luminance and can suppress a reduction in contrast.

It is a perspective view which shows an example of the wire grid type polarizer of this invention. It is a perspective view which shows the other example of the wire grid type polarizer of this invention. It is a perspective view which shows the other example of the wire grid type polarizer of this invention. It is a perspective view which shows the other example of the wire grid type polarizer of this invention. It is a perspective view which shows the other example of the wire grid type polarizer of this invention. It is a perspective view which shows the other example of the wire grid type polarizer of this invention. It is sectional drawing which shows an example of the liquid crystal display device of this invention.

<Wire grid polarizer>
In the wire grid polarizer of the present invention, a plurality of ridges whose width gradually decreases from the bottom to the top are parallel to each other through a flat portion formed between the ridges and have a predetermined pitch. A light-transmitting substrate formed on the surface, a first reflective layer made of a metal material covering the first side surface of the ridge, and between the first side surface of the ridge and the first reflective layer And a first absorption layer made of a light-absorbing material that absorbs light rather than a metal material, covering the entire surface of the first side surface of the ridge. The first reflective layer and the first absorption layer on the first side surface of the ridge have a strip shape extending in the length direction of the ridge, and correspond to the fine metal wires constituting the wire grid polarizer. In the present invention, the surface of the light transmissive substrate described above is formed to extend in one direction of the light transmissive substrate at a predetermined pitch. For example, the cross-sectional shape in the length direction is opposed to a triangular or trapezoidal ridge. One of the side surfaces is referred to as a first side surface and the other is referred to as a second side surface.

The wire grid type polarizer of the present invention includes an underlayer made of a metal material that exists between the first side surface of the ridge and the first absorption layer and covers the entire surface of the first side surface of the ridge. You may have. Furthermore, you may have the 2nd absorption layer which consists of a light absorptive material which coat | covers the whole surface of the said 2nd side surface on the 2nd side surface of the protruding item | line which is the other side surface of a protruding item | line. The wire grid polarizer of the present invention may further include a second reflective layer made of a metal material that covers the surface of the second absorption layer.
The coating in the present invention is not limited to the case where the layer is directly formed on the surface, but includes the case where the layer is formed so as to cover the surface via another layer.
In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

(Light transmissive substrate)
The light transmissive substrate is a substrate having light transmittance in the wavelength range of use of the wire grid polarizer. The light transmissive property means that light is transmitted, and the used wavelength range is specifically a range of 400 nm to 800 nm. Preferably, the average light transmittance in the range of 400 nm to 800 nm is 85% or more.

  In the present invention, the term “ridge” refers to a portion rising from the main surface (flat portion) of the light-transmitting substrate and extending in one direction. The ridges are integral with the main surface of the light-transmitting substrate, and may be made of the same light-transmitting material as the main surface of the light-transmitting substrate, or of a light-transmitting material different from the main surface of the light-transmitting substrate. May be. The ridge is preferably integral with the main surface of the light transmissive substrate and made of the same material as the main surface of the light transmissive substrate, and is formed by molding at least the main surface of the light transmissive substrate. Preferably it is a strip.

The plurality of ridges may be formed so that corresponding side surfaces of the ridges are formed substantially in parallel, and may not be formed completely in parallel. Each ridge is preferably a straight line that most easily exhibits optical anisotropy in a plane, but may be a curved line or a polygonal line as long as adjacent ridges do not contact each other.
The shape of the cross-section in the direction perpendicular to the length direction and the main surface of the light-transmitting substrate is substantially constant over the length direction, and all of the cross-section shapes of the plurality of ridges are substantially constant. Preferably there is. The cross-sectional shape of the ridge is a shape in which the width gradually decreases from the bottom (the main surface of the light-transmitting substrate) toward the top. Specific examples of the cross-sectional shape include a triangle and a trapezoid. The cross-sectional shape may have a curved corner or side (side surface). Moreover, it is preferable that the pitch width between the plurality of protrusions formed on the main surface of the light-transmitting substrate in parallel or substantially parallel, that is, the width of the flat portion is constant or substantially constant.

  In the present invention, the top of the ridge means a portion where the highest cross-sectional portion is continuous in the length direction. The top of the ridge may be a surface or a line. For example, when the cross-sectional shape is trapezoidal, the top portion forms a surface, and when the cross-sectional shape is triangular, the top portion forms a line. In the present invention, the surface other than the top of the ridge is referred to as a side surface of the ridge. In addition, the flat part (bottom surface of the groove | channel formed from two adjacent protrusions) between two adjacent protrusions is considered not the surface of a protrusion but the main surface of a light-transmitting board | substrate.

  Examples of the material for the light-transmitting substrate include a photo-curing resin, a thermoplastic resin, and glass. A photo-curing resin or a thermoplastic resin is preferable from the viewpoint that ridges can be formed by an imprint method described later. Photocuring resins are particularly preferred because they can form ridges by the printing method and are excellent in heat resistance and durability. As the photocurable resin, a photocurable resin obtained by photocuring a photocurable composition that can be photocured by photoradical polymerization is preferable from the viewpoint of productivity.

  As a photocurable composition, the thing whose contact angle with respect to the water of the cured film after photocuring becomes 90 degrees or more is preferable. If the contact angle of the cured film with respect to water is 90 ° or more, when forming the ridges by the photoimprint method, the mold can be easily released from the mold, and the transfer can be performed with high accuracy. Type polarizers can fully exhibit their intended performance. Further, even if the contact angle is high, there is no hindrance to adhesion of each absorbing layer or underlayer.

(First reflective layer)
The 1st reflective layer has made the filament extended in the length direction of a protruding item | line, and is corresponded to the metal fine wire which comprises a wire grid type polarizer. The first reflective layer covers a part or the entire surface of the first side surface of the ridge. The first reflective layer preferably covers a part of the first side surface of the ridge from the viewpoint that the back surface s-polarized reflectance becomes lower. The first reflective layer may cover part or all of the top of the ridge. Further, the first reflective layer may cover a part of the flat portion adjacent to the first side surface of the ridge.
The first reflective layer covering the first side surface of the ridge is usually continuous. The first side surface of the ridge is preferably continuously covered with the first reflective layer, but a very small part of the first side surface is not covered with the first reflective layer due to manufacturing problems or the like. In some cases. Even in this case, if the first side surface is substantially continuously covered by the first reflective layer, it is considered that the first side surface is continuously covered by the first reflective layer.

The metal material of the first reflective layer is not particularly limited as long as it has a high visible light reflectivity and sufficient conductivity, and is preferably a material that takes into account characteristics such as corrosion resistance.
Examples of the metal material include simple metals, alloys, metals containing dopants or impurities, and the like. Specific examples include aluminum, silver, magnesium, aluminum-based alloys, silver-based alloys, and the like. From the viewpoint of high reflectivity for visible light, low visible light absorption, and high conductivity, aluminum, aluminum Alloys, silver and magnesium are preferable, and aluminum and aluminum alloys are particularly preferable.

(Second reflection layer)
The 2nd reflective layer has made the filament extended in the length direction of a protruding item | line, and is corresponded to the metal fine wire which comprises a wire grid type polarizer. The second reflective layer covers a part or the entire surface of the second side surface of the ridge. The second reflective layer preferably covers a part of the second side surface of the ridge from the viewpoint that the back surface s-polarized reflectance becomes lower. The second reflective layer may cover part or all of the top of the ridge. The second reflective layer may cover a part of the flat portion adjacent to the second side surface of the ridge.
The second reflective layer covering the second side surface of the ridge is usually continuous in the longitudinal direction of the second side surface. The second side surface of the ridge is preferably continuously covered with the second reflective layer, but a very small portion of the second side surface is not covered with the second reflective layer due to manufacturing problems or the like. In some cases. Even in this case, if the second side surface is substantially continuously covered with the second reflective layer, it is considered that the second side surface is continuously covered with the second reflective layer.

The presence of the second reflective layer increases the amount of the metal material that covers the ridges, so that the extinction ratio can be improved with little decrease in transmittance.
Examples of the metal material for the second reflective layer include the same materials as those for the first reflective layer.

(First absorption layer)
The first absorbing layer exists between the first side surface of the ridge and the first reflective layer, and covers the entire surface of the first side surface of the ridge. The first absorption layer may cover a part or all of the top of the ridge. It is preferable that the first absorption layer does not cover the top of the ridge from the viewpoint of excellent p-polarized light transmittance. The 1st absorption layer may coat a part of flat part adjacent to the 1st side of a ridge.
As for the 1st absorption layer which coat | covers the 1st side surface of a protruding item | line, it is usual that it is continuing in the longitudinal direction of the 1st side surface. The first side surface of the ridge is preferably completely covered with the first absorbent layer, but only a small part of the first side surface is not covered with the first absorbent layer due to manufacturing problems or the like. There is also. Even in this case, if almost the entire first side surface is covered with the first absorption layer, it is considered that the entire first side surface is covered with the first absorption layer.

When the first absorption layer covers the entire surface of the first side surface of the ridge, the back surface s-polarized reflectance of the wire grid polarizer is lowered.
The light absorbing material of the first absorption layer may be a material that absorbs light more than the metal material of the first reflection layer. The degree of light absorption of each material is the absorption rate of light having a wavelength of 550 nm in a thin film state having a thickness of 60 nm. Absorption rate is defined by the following equation.
Absorptivity (%) of light having a wavelength of 550 nm = 100− [Transmittance (%) of light having a wavelength of 550 nm] − [Reflectivity (%) of light having a wavelength of 550 nm]

  Specific examples of the light absorbing material include low reflective metals such as nickel, chromium, titanium, tungsten, platinum, molybdenum, and vanadium; inorganic oxides such as chromium oxide and aluminum oxide; titanium nitride, silicon nitride, and the like. Inorganic nitrides; inorganic carbides such as aluminum carbide and molybdenum carbide; carbon compounds such as carbon black and carbon nanotubes, etc., but inorganic oxides react with metal and oxygen when forming the first absorption layer This is not preferable because the ridges are easily deformed by the heat generated by. As the light-absorbing material, nickel, chromium, and titanium are preferable because they have a large light absorption rate and high productivity.

(Underlayer)
The underlayer exists between the first side surface of the ridge and the first absorption layer, and covers the entire surface of the first side surface of the ridge.
The underlayer may cover part or all of the top of the ridge. Further, the underlayer may cover a part of the flat portion adjacent to the first side surface of the ridge.
The base layer covering the first side surface of the ridge is usually continuous in the longitudinal direction of the first side surface. It is preferable that the first side surface of the ridge is completely covered with the underlayer. However, a part of the first side surface may not be covered with the underlayer due to a manufacturing problem or the like. Even in this case, if almost the entire first side surface is covered with the underlayer, it is considered that the entire first side surface is covered with the underlayer.

Since the first absorption layer made of the light-absorbing material has a large compressive stress, the ridge is easily deformed (bent) in a direction perpendicular to the length direction thereof. The underlayer made of a metal material has an action of relaxing the compressive stress in the first absorption layer.
Therefore, the metal material of the underlayer is preferably one that generates less compressive stress, and specifically includes aluminum, silver, magnesium, aluminum-based alloys, silver-based alloys, etc., and reflectivity in the visible light region. From the viewpoint of high, aluminum and aluminum-based alloys are preferable.

(Second absorption layer)
The second absorption layer covers the entire second side surface of the ridge. The second absorption layer may cover a part or all of the top of the ridge, or may cover a part of the flat portion adjacent to the second side surface of the ridge.
In general, the second absorbent layer covering the second side surface of the ridge is continuous in the longitudinal direction of the second side surface. The second side surface of the ridge is preferably completely covered with the second absorbent layer, but only a small portion of the second side surface is not covered with the second absorbent layer due to manufacturing problems or the like. There is also. Even in this case, if almost the entire second side surface is covered with the second absorption layer, it is considered that the entire second side surface is covered with the second absorption layer.

Since the first absorption layer made of the light-absorbing material has a large compressive stress, the ridge is easily deformed (bent) in a direction perpendicular to the length direction thereof. The 2nd absorption layer which consists of light absorption materials has the effect | action which cancels compressive stress by opposing a 1st absorption layer.
Therefore, the light absorbing material of the second absorption layer may be the same as the light absorbing material of the first absorption layer, and is exactly the same.

<Method for producing wire grid polarizer>
A wire grid polarizer is manufactured by forming a light-transmitting substrate having a plurality of protrusions formed on a surface thereof in parallel with each other at a predetermined pitch, and then sequentially forming each layer.

(Production of light-transmitting substrate)
Examples of a method for manufacturing a light-transmitting substrate include an imprint method (an optical imprint method and a thermal imprint method), a lithography method, and the like. The imprinting method is preferable from the viewpoint of being able to be formed, and the optical imprinting method is particularly preferable from the viewpoint that the ridges can be formed with higher productivity and the groove of the mold can be accurately transferred.

  In the optical imprint method, for example, a mold in which a plurality of grooves are formed in parallel with each other at a predetermined pitch by a combination of electron beam drawing and etching, and the grooves of the mold are formed on the surface of an arbitrary substrate. It is a method of transferring to the photocurable composition applied to the film and simultaneously photocuring the photocurable composition.

Specifically, the production of the light-transmitting substrate by the photoimprint method is preferably performed through the following steps (i) to (iv).
(I) The process of apply | coating a photocurable composition to the surface of a base material.
(Ii) A step of pressing a mold in which a plurality of grooves are formed in parallel with each other at a predetermined pitch against the photocurable composition so that the grooves are in contact with the photocurable composition.
(Iii) Radiation (ultraviolet ray, electron beam, etc.) is applied to the photocurable composition while the mold is pressed against the photocurable composition to cure the photocurable composition to have a plurality of ridges corresponding to the mold grooves. Producing a light-transmitting substrate;
(Iv) A step of separating the mold from the light transmissive substrate.
In addition, the obtained light-transmitting substrate on the base material can form each layer described later while being integrated with the base material. If necessary, the light-transmitting substrate and the base material can be separated after forming each layer. Furthermore, after separating the light-transmitting substrate produced on the base material from the base material, each layer described later can be formed.

Specifically, the production of the light-transmitting substrate by the thermal imprint method is preferably performed through the following steps (i) to (iii).
(I) A step of forming a transfer film of a thermoplastic resin on the surface of a substrate, or a step of producing a transfer film of a thermoplastic resin.
(Ii) Glass mold temperature (Tg) or melting point (Tm) of the thermoplastic resin so that the groove is in contact with the film to be transferred or the film to be transferred in a mold in which a plurality of grooves are formed in parallel with each other at a constant pitch. A step of producing a light-transmitting substrate having a plurality of ridges corresponding to the grooves of the mold by being pressed against the heated transfer film or transfer film.
(Iii) A step of cooling the light transmissive substrate to a temperature lower than Tg or Tm to separate the mold from the light transmissive substrate.
In addition, the obtained light-transmitting substrate on the base material can form each layer described later while being integrated with the base material. If necessary, the light-transmitting substrate and the base material can be separated after forming each layer. Furthermore, after separating the light-transmitting substrate produced on the base material from the base material, each layer described later can be formed.

  Examples of the mold material used in the imprint method include silicon, nickel, quartz, and resin. Resin is preferable from the viewpoint of transfer accuracy. Examples of the resin include a fluorine-based resin (ethylene-tetrafluoroethylene copolymer, etc.), a cyclic olefin, a silicone resin, an epoxy resin, an acrylic resin, and the like. From the viewpoint of mold accuracy, a photocurable acrylic resin is used. preferable. The resin mold preferably has an inorganic film having a thickness of 2 to 10 nm on the surface from the viewpoint of repeated transfer durability. As the inorganic film, an oxide film such as silicon oxide, titanium oxide, and aluminum oxide is preferable.

(Formation of each layer)
Each layer is preferably formed by a vapor deposition method. Examples of the vapor deposition method include physical vapor deposition (PVD) and chemical vapor deposition (CVD), and vacuum vapor deposition, sputtering, and ion plating are preferred, and vacuum vapor deposition is particularly preferred. In the vacuum evaporation method, it is easy to control the incident direction of the fine particles to be attached to the light-transmitting substrate, and it is easy to perform the oblique evaporation method described later. Since each layer needs to be formed by selectively vapor-depositing each material on each side surface of the ridge, an oblique vapor deposition method by a vacuum vapor deposition method is most preferable.

(Formation of underlayer)
Specifically, the underlayer is made of metal from a direction that is substantially orthogonal to the length direction of the ridges and that forms an angle of 25 to 40 ° to the first side surface with respect to the height direction of the ridges. The material can be formed by vapor deposition under the condition that the vapor deposition amount is 3 to 15 nm. The angle is preferably 30 to 45 °, and the deposition amount is preferably 5 to 15 nm.
The condition that the deposition amount is 3 to 15 nm is formed by vapor-depositing a metal or a metal compound on the surface of a region where the ridge is not formed (flat flat portion) when the metal layer is formed on the ridge. In this case, the base layer is formed by the oblique deposition method. In addition, the conditions of the vapor deposition amount in the formation of the following 1st absorption layer, 2nd absorption layer, 1st reflection layer, and 2nd reflection layer are also the same.

(Formation of first absorption layer)
Specifically, the first absorbent layer is substantially orthogonal to the length direction of the ridges and forms an angle of 25 to 40 ° on the first side surface side with respect to the height direction of the ridges. The light absorbing material can be formed from the direction by vapor deposition under the condition that the vapor deposition amount is 3 to 20 nm. The angle is preferably 30 to 35 °, and the deposition amount is preferably 5 to 15 nm.

(Formation of second absorption layer)
Specifically, the second absorbent layer is substantially orthogonal to the length direction of the ridges and forms an angle of 25 to 40 ° on the second side surface side with respect to the height direction of the ridges. The light absorbing material can be formed from the direction by vapor deposition under the condition that the vapor deposition amount is 3 to 20 nm. The angle is preferably 30 to 40 °, and the deposition amount is preferably 5 to 15 nm.

(Formation of the first reflective layer)
Specifically, the first reflective layer is substantially orthogonal to the length direction of the ridges and forms an angle of 25 to 50 ° on the first side surface side with respect to the height direction of the ridges. The metal material can be formed from the direction by vapor deposition under the condition that the vapor deposition amount is 15 to 50 nm. The angle is preferably 30 to 45 °, and the deposition amount is preferably 20 to 45 nm.

(Formation of second reflective layer)
Specifically, the second reflective layer is substantially orthogonal to the length direction of the ridges and forms an angle of 25 to 50 ° on the second side surface side with respect to the height direction of the ridges. The metal material can be formed from the direction by vapor deposition under the condition that the vapor deposition amount is 15 to 50 nm. The angle is preferably 30 to 45 °, and the deposition amount is preferably 20 to 45 nm.

<Embodiment of Wire Grid Type Polarizer>
Hereinafter, embodiments of the wire grid polarizer of the present invention will be described with reference to the drawings. The following diagram is a schematic diagram, and an actual wire grid polarizer does not have a theoretical and ideal shape as illustrated. For example, in an actual wire grid type polarizer, the shape of protrusions or the like is somewhat collapsed, and the thickness of each layer is not uniform.
The dimensions of the ridges and each layer in the present invention are as follows: in the scanning electron microscope image or transmission electron microscope image of the cross section of the wire grid polarizer, the dimensions of the five ridges and each layer on the ridges are as follows. The maximum value is measured and the five maximum values are averaged.

[First Embodiment]
FIG. 1 is a perspective view showing a first embodiment of a wire grid polarizer of the present invention. In the wire grid polarizer 10, a plurality of ridges 12 having a trapezoidal cross-sectional shape extending in the direction of the arrow A on the drawing are parallel to each other via a flat portion 13 of a groove formed between the ridges 12. And a light-transmitting substrate 14 formed on the surface at a predetermined pitch Pp, a first reflective layer 20 made of a metal material covering a part of the surface of the first side surface 16 of the ridge 12, and a convex A first absorbing layer 22 made of a light-absorbing material, which exists between the first side surface of the strip 12 and the first reflective layer 20 and covers the entire surface of the first side surface 16 of the convex strip 12; Have. The first reflective layer 20 extends in the length direction of the ridges 12 to form a fine metal wire.

(Light transmissive substrate)
Pp is the sum of the width Dpb of the bottom of the ridge 12 and the width of the flat portion 13 formed between the ridges 12. Pp is preferably 300 nm or less, preferably in the range of 50 to 300 nm, and more preferably in the range of 50 to 250 nm. When Pp is 300 nm or less, a high surface s-polarized reflectance is exhibited, and a high degree of polarization is exhibited even in a short wavelength region of about 400 nm. Moreover, the coloring phenomenon by diffraction is suppressed. Moreover, if Pp is 50-200 nm, it will be easy to form each layer by vapor deposition.

The ratio of Dpb to Pp (Dpb / Pp) is preferably 0.1 to 0.7, and more preferably 0.25 to 0.55. When Dpb / Pp is 0.1 or more, a high degree of polarization is exhibited. By setting Dpb / Pp to 0.7 or less, coloring of transmitted light due to interference can be suppressed.
Dpb is preferably 30 to 100 nm from the viewpoint of easily forming each layer by vapor deposition.

  When the cross-sectional shape of the ridge is trapezoidal, the width Dpt of the top portion 19 of the ridge 12 is preferably less than or equal to half of Dpb, more preferably 40 nm or less, and even more preferably 20 nm or less. If Dpt is less than or equal to half of Dpb, the p-polarized light transmittance is higher and the angle dependency is sufficiently low.

The height Hp of the ridges 12 is preferably 80 to 500 nm, more preferably 80 to 400 nm, still more preferably 120 to 300 nm, and most preferably 120 to 270 nm. If Hp is 80 nm or more, the polarization separation ability is sufficiently high. If Hp is 500 nm or less, the chromatic dispersion is small. Moreover, if Hp is 80-270 nm, it will be easy to form each layer by vapor deposition.
The inclination angle θ1 of the first side surface 16 with respect to the main surface forming the flat portion of the light-transmitting substrate and the inclination angle θ2 of the second side surface 18 are preferably 30 ° or more and less than 90 °, preferably 50 ° or more and less than 90 °. Is more preferable, more preferably 70 or more and less than 90 °, and most preferably 75 ° or more and less than 90 °. θ1 and θ2 may be the same or different.
The thickness Hs of the light transmissive substrate 14 is preferably 0.5 to 1000 μm, and more preferably 1 to 40 μm.

(First reflective layer)
It is preferable that the maximum value Dr1 of the thickness of the first reflective layer 20 in the width direction of the ridges 12 satisfies the following formula (I).
0.2 × (Pp−Dpb) ≦ Dr1 ≦ 0.5 × (Pp−Dpb) (I).
When Dr1 is 0.2 × (Pp−Dpb) or more, high p-polarized light transmittance is exhibited and chromatic dispersion is small. When Dr1 is 0.5 × (Pp−Dpb) or less, the polarization separation ability is sufficiently high.

  The height Hr1 of the first reflective layer 20 is preferably 80 to 500 nm, more preferably 80 to 400 nm, and still more preferably 120 to 300 nm. If Hr1 is 80 nm or more, crystallization of the first reflective layer 20 is suppressed, and high s-polarized reflectance is exhibited. If Hr1 is 500 nm or less, the polarization separation ability is sufficiently high even in a short wavelength region.

Hr1 / Hp is preferably 0.5 to 1, and more preferably 0.6 to 1. When Hr1 / Hp is 1 or less, the polarization separation ability is improved. If Hr1 / Hp is 0.5 or more, the angle dependency of the optical characteristics is sufficiently low.
When the first reflective layer 20 covers a part or all of the top of the ridge 12, the height at the top is preferably 20 nm or less from the viewpoint of suppressing a decrease in transmittance.

(First absorption layer)
3-20 nm is preferable and, as for the maximum value Da1 of the thickness of the 1st absorption layer 22 in the width direction of the protruding item | line 12, 5-15 nm is more preferable. If Da1 is 3 nm or more, the back surface s-polarized reflectance is sufficiently low. If Da1 is 20 nm or less, the compressive stress of the first absorption layer 22 can be kept low.
The height Ha1 of the first absorption layer 22 is substantially the same as Hp because the first absorption layer is coated and formed on the entire first side surface.

[Second Embodiment]
FIG. 2 is a perspective view showing a second embodiment of the wire grid polarizer of the present invention. In the wire grid polarizer 10, a plurality of ridges 12 having a trapezoidal cross-sectional shape are formed on the surface in parallel with each other and at a predetermined pitch Pp through a flat portion 13 of a groove formed between the ridges 12. The light-transmitting substrate 14, the first reflective layer 20 made of a metal material covering a part of the surface of the first side surface 16 of the ridge 12, the first side surface of the ridge 12 and the first A first absorbing layer 22 made of a light-absorbing material and covering the entire surface of the first side surface 16 of the ridge 12, and the ridge 12 and the first absorption layer 22. And a base layer 24 made of a metal material that covers the entire surface of the first side surface 16 of the ridge 12.
In the second embodiment, the description of the same configuration as that of the wire grid polarizer 10 of the first and second embodiments is omitted.

(Underlayer)
3-20 nm is preferable and, as for the maximum value Db1 of the thickness of the width direction of the protruding item | line 12 of the base layer 24, 5-15 nm is more preferable. If Db1 is 3 nm or more, the compressive stress in the first absorption layer 22 can be sufficiently relaxed. If Db1 is 20 nm or less, an increase in the back surface s-polarized reflectance can be suppressed.
The height Hb1 of the underlayer 24 is substantially the same as Hp because the underlayer is covered and formed on the entire first side surface.

[Third Embodiment]
FIG. 3 is a perspective view showing a third embodiment of the wire grid polarizer of the present invention. In the wire grid polarizer 10, a plurality of ridges 12 having a trapezoidal cross-sectional shape are formed on the surface in parallel with each other and at a predetermined pitch Pp through a flat portion 13 of a groove formed between the ridges 12. The light-transmitting substrate 14, the first reflective layer 20 made of a metal material covering a part of the surface of the first side surface 16 of the ridge 12, the ridge 12 and the first reflective layer 20, Between the first absorption layer 22 made of a light-absorbing material and covering the entire surface of the second side surface 18 of the ridge 12. A second absorption layer made of a light-absorbing material.
In the third embodiment, the description of the same configuration as that of the wire grid polarizer 10 of the first embodiment is omitted.

(Second absorption layer)
3-20 nm is preferable and, as for the maximum value Da2 of the thickness of the width direction of the protruding item | line 12 of the 2nd absorption layer 26, 5-15 nm is more preferable. If Da2 is 3 nm or more, the back surface s-polarized reflectance is sufficiently low. If Da2 is 20 nm or less, the compressive stress of the second absorption layer 26 can be kept low.
Da2 is preferably 0.55 to 2 times the thickness of Da1 and more preferably 0.55 to 1.5 from the viewpoint of canceling the compressive stress between the first absorption layer 22 and the second absorption layer 26. .
The height Ha2 of the second absorption layer 26 is substantially the same as Hp because the second absorption layer is coated and formed on the entire second side surface.

[Fourth Embodiment]
FIG. 4 is a perspective view showing a fourth embodiment of the wire grid polarizer of the present invention. In the wire grid polarizer 10, a plurality of ridges 12 having a trapezoidal cross-sectional shape are formed on the surface in parallel with each other and at a predetermined pitch Pp through a flat portion 13 of a groove formed between the ridges 12. The light-transmitting substrate 14, the first reflective layer 20 made of a metal material covering a part of the surface of the first side surface 16 of the ridge 12, the first side surface of the ridge 12 and the first A first absorbing layer 22 made of a light-absorbing material and covering the entire surface of the first side surface 16 of the ridge 12, and the ridge 12 and the first absorption layer 22. A light-absorbing material covering the entire surface of the first side surface 16 of the ridge 12 and covering the entire surface of the second side surface 18 of the ridge 12. And a second absorption layer 26 made of
In 4th Embodiment, description is abbreviate | omitted about the same structure as the wire grid type polarizer 10 of 1st-3rd embodiment.

[Fifth Embodiment]
FIG. 5 is a perspective view showing a fifth embodiment of the wire grid polarizer of the present invention. In the wire grid polarizer 10, a plurality of ridges 12 having a trapezoidal cross-sectional shape are formed on the surface in parallel with each other and at a predetermined pitch Pp through a flat portion 13 of a groove formed between the ridges 12. Between the projected light transmitting substrate 14, the first reflective layer 20 made of a metal material covering a part of the first side surface 16 of the ridge 12, and between the ridge 12 and the first reflective layer 20. A first absorbing layer 22 made of a light-absorbing material that covers the entire surface of the first side surface 16 of the ridge 12, and a metal that covers a part of the second side surface 18 of the ridge 12. The second reflective layer 28 made of a material, and the second reflective layer 28 made of a light-absorbing material, which exists between the ridge 12 and the second reflective layer 28 and covers the entire surface of the second side surface 18 of the ridge 12. 2 absorption layers 26.
In the fifth embodiment, the description of the same configuration as that of the wire grid polarizer 10 of the first to fourth embodiments is omitted.

(Second reflection layer)
The maximum value Dr2 of the thickness in the width direction of the ridges 12 of the second reflective layer 28 preferably satisfies the following formula (II).
0.2 × (Pp−Dpb) ≦ Dr2 ≦ 0.5 × (Pp−Dpb) (II)
If Dr2 is 0.2 × (Pp−Dpb) or more, high p-polarized light transmittance is exhibited and chromatic dispersion is small. When Dr2 is 0.5 × (Pp−Dpb) or less, the polarization separation ability is sufficiently high.

  The height Hr2 of the second reflective layer 28 is preferably 80 to 500 nm, more preferably 80 to 400 nm, and still more preferably 120 to 300 nm. If Hr2 is 80 nm or more, crystallization of the second reflective layer 28 is suppressed and high s-polarized reflectance is exhibited. If Hr2 is 500 nm or less, the polarization separation ability is sufficiently high even in a short wavelength region.

Hr2 / Hp is preferably 0.5 to 1, and more preferably 0.6 to 1. If Hr2 / Hp is 1 or less, the polarization separation ability is improved. If Hr2 / Hp is 0.5 or more, the angle dependency of the optical characteristics is sufficiently low.
When the second reflective layer 28 covers a part or the whole of the top of the ridge 12, the height at the top is preferably 20 nm or less from the viewpoint of suppressing a decrease in transmittance.
In the description of FIGS. 1 to 5 of the wire grid polarizer of each of the first to fifth embodiments of the present invention described above, the first side of the ridge is the right side of the ridge, and the first An example in which the first absorption layer, the first reflection layer, and the base layer are formed on the side surface will be described. The second side surface of the ridge is the left side surface of the ridge, and the second side surface The example in which the second absorbing layer and the second reflecting layer are formed has been described. Of course, the first side surface of the ridges in each drawing is the left side surface of the ridges, and the second side surface of the ridges is the same. It is good also as a surface on the right side of a protruding item | line.

<The manufacturing method of the wire grid type polarizer of each embodiment>
[Method for Manufacturing Wire Grid Polarizer of First Embodiment]
In the wire grid polarizer 10 of the first embodiment, the first absorption layer 22 is formed on the surface of the first side surface 16 of the ridge 12 of the light-transmitting substrate 14, and the first absorption layer 22 It can be manufactured by forming the first reflective layer 20 on the surface.

(Formation of first absorption layer)
As shown in FIG. 6, the first absorbent layer 22 is substantially orthogonal to the length direction L of the ridges 12 and on the first side face 16 side with respect to the height direction H of the ridges 12. the light-absorbing material from a direction V1 constituting 25-40 ° angle theta ^R, the deposition amount described above can be formed by depositing the condition to be 3 to 20 nm.

Vapor deposition may be performed n times (where n is an integer of 2 or more) under the condition that the total vapor deposition amount is 3 to 20 nm. i-th (where, i is an integer of 1 to n-1.) angle theta ^R _i and i + 1 th angle theta ^R _{i + 1} of is preferably _{^{θ R i + 1 <θ R}} i.

  Deposition sources include light absorbing materials (low reflective metals such as nickel, chromium, titanium, tungsten, platinum, molybdenum and vanadium; inorganic oxides such as chromium oxide and aluminum oxide; inorganic nitrides such as titanium nitride and silicon nitride) Inorganic carbides such as aluminum carbide and molybdenum carbide; carbon compounds such as carbon black and carbon nanotubes, etc.), and nickel, chromium and titanium are preferred from the standpoints of high absorption rate and high productivity.

(Formation of the first reflective layer)
As shown in FIG. 6, the first reflective layer 20 is substantially orthogonal to the length direction L of the ridges 12 and on the first side surface 16 side with respect to the height direction H of the ridges 12. the metallic material from a direction V1 constituting 25-50 ° angle theta ^R, the deposition amount described above can be formed by depositing the condition to be 15 to 50 nm.

Vapor deposition may be performed n times (where n is an integer of 2 or more) under the condition that the total deposition amount is 15 to 50 nm. i-th (where, i is an integer of 1 to n-1.) angle theta ^R _i and i + 1 th angle theta ^R _{i + 1} of is preferably _{^{θ R i + 1 <θ R}} i.

  Examples of the deposition source include metal materials (aluminum, silver, magnesium, aluminum-based alloys, silver-based alloys, etc.), high reflectivity for visible light, little absorption of visible light, and high conductivity. Therefore, aluminum, aluminum-based alloy, silver and magnesium are preferable, and aluminum and aluminum-based alloy are particularly preferable.

[Method for Manufacturing Wire Grid Polarizer of Second Embodiment]
In the wire grid polarizer 10 of the second embodiment, a base layer 24 is formed on the surface of the first side surface 16 of the ridge 12 of the light-transmitting substrate 14, and the first absorption is formed on the surface of the base layer 24. It can be manufactured by forming the layer 22 and forming the first reflective layer 20 on the surface of the first absorption layer 22.
In the second embodiment, the description of the same configuration as that of the wire grid polarizer 10 of the first embodiment is omitted.

(Formation of underlayer)
As shown in FIG. 6, the base layer 24 is substantially orthogonal to the length direction L of the ridges 12 and is 25 to 40 on the first side face 16 side with respect to the height direction H of the ridges 12. the metallic material from a direction V1 constituting a degree angle theta ^R, the deposition amount described above can be formed by depositing the condition to be 3 to 15 nm.

Deposition may be performed n times (where n is an integer of 2 or more) under the condition that the total deposition amount is 3 to 15 nm. i-th (where, i is an integer of 1 to n-1.) angle theta ^R _i and i + 1 th angle theta ^R _{i + 1} of is preferably _{^{θ R i + 1 <θ R}} i.

  Examples of the deposition source include metal materials (aluminum, silver, magnesium, aluminum-based alloys, silver-based alloys, etc.), and aluminum and aluminum-based alloys are preferable from the viewpoint of high reflectivity in the visible light region.

[Method for Manufacturing Wire Grid Polarizer of Third Embodiment]
The wire grid polarizer 10 of the third embodiment can be manufactured by adding the following steps to the manufacturing method of the first embodiment.
At an arbitrary stage, a step of forming the second absorption layer 26 on the surface of the second side face 18 of the ridge 12 of the light transmissive substrate 14 is added.
In the third embodiment, the description of the same configuration as that of the wire grid polarizer 10 of the first embodiment is omitted.

(Formation of second absorption layer)
As shown in FIG. 6, the second absorbent layer 26 is substantially orthogonal to the length direction L of the ridges 12 and on the second side surface 18 side with respect to the height direction H of the ridges 12. the light-absorbing material from a direction V2 constituting 25-40 ° angle theta ^L, the deposition amount described above can be formed by depositing the condition to be 3 to 20 nm.

Vapor deposition may be performed n times (where n is an integer of 2 or more) under the condition that the total vapor deposition amount is 3 to 20 nm. i-th (where i is an integer from 1 to n−1).
) Angle θ ^L _i and the (i + 1) th angle θ ^L _{i + 1} are preferably θ ^L _{i + 1} <θ ^L _i .

  Examples of the evaporation source include light absorbing materials (nickel, chromium, titanium, tungsten, platinum, molybdenum, vanadium nickel, chromium, titanium, etc.). From the viewpoint of the high absorption rate and high productivity, nickel, Chromium and titanium are preferred.

[Method for Manufacturing Wire Grid Polarizer of Fourth Embodiment]
The wire grid polarizer 10 of the fourth embodiment can be manufactured by adding the following steps to the manufacturing method of the second embodiment.
At an arbitrary stage, a step of forming the second absorption layer 26 on the surface of the second side face 18 of the ridge 12 of the light transmissive substrate 14 is added.
In 4th Embodiment, description is abbreviate | omitted about the same structure as the wire grid type polarizer 10 of 1st-3rd embodiment.

[Method for Manufacturing Wire Grid Polarizer of Fifth Embodiment]
The wire grid polarizer 10 of the fifth embodiment can be manufactured by adding the following steps to the manufacturing method of the third embodiment.
At an optional stage, a step of forming the second reflective layer 28 on the surface of the second absorption layer 26 is added.
In the fifth embodiment, the description of the same configuration as that of the wire grid polarizer 10 of the first to fourth embodiments is omitted.

(Formation of second reflective layer)
As shown in FIG. 6, the second reflective layer 28 is substantially orthogonal to the length direction L of the ridges 12 and on the second side surface 18 side with respect to the height direction H of the ridges 12. It can be formed by vapor-depositing a metal material from the direction V2 forming an angle θ ^L of 25 to 50 ° under the condition that the vapor deposition amount is 15 to 50 nm.

Vapor deposition may be performed n times (where n is an integer of 2 or more) under the condition that the total deposition amount is 15 to 50 nm. i-th (where, i is an integer of 1 to n-1.) angle theta ^L _i and i + 1 th angle theta ^L _{i + 1} of is preferably _{^{θ L i + 1 <θ L}} i.

  Examples of the deposition source include metal materials (aluminum, silver, magnesium, aluminum-based alloys, silver-based alloys, etc.), high reflectivity for visible light, little absorption of visible light, and high conductivity. Therefore, aluminum, aluminum-based alloy, silver and magnesium are preferable, and aluminum and aluminum-based alloy are particularly preferable.

Angle (theta) ^R ((theta) ^L ) in the manufacturing method of 1st-5th embodiment can be adjusted by using the following vapor deposition apparatus, for example.
An angle θ ^R (θ ^L ) is formed on the first side surface 16 (second side surface 18) side with respect to the height direction H of the ridge 12 and substantially perpendicular to the length direction L of the ridge 12. The vapor deposition apparatus which can change the inclination of the light-transmitting substrate 14 arrange | positioned facing a vapor deposition source so that a vapor deposition source may be located on the extension line | wire of the direction V1 (V2) to make.

  In the wire grid polarizer of the present invention described above, the cross-sectional shape of the plurality of ridges formed on the surface of the light-transmitting substrate is such that the width gradually decreases from the bottom toward the top. In addition, since the first side surface of the ridge is covered with the first reflective layer, it exhibits a high degree of polarization and a high p-polarized light transmittance. Moreover, since the 1st absorption layer which coat | covers the whole surface of the 1st side surface of a protruding item | line exists between a protruding item | line and a 1st reflective layer, a back surface s polarized light reflectance is low.

  Moreover, in the manufacturing method of the wire grid type polarizer of the present invention described above, the first side surface side is substantially orthogonal to the length direction of the ridges and the height direction of the ridges. A light-absorbing material is vapor-deposited from a direction that forms an angle of 25 to 40 ° under the condition that the vapor deposition amount is 3 to 20 nm to form a first absorption layer, which is substantially orthogonal to the length direction of the ridges. In addition, a metal material is vapor-deposited from a direction that forms an angle θ of 25 to 40 ° on the first side surface side with respect to the height direction of the ridges, under the condition that the vapor deposition amount is 15 to 50 nm. Since the reflective layer is formed, a wire grid type polarizer having a high degree of polarization and p-polarized light transmittance and a low back surface s-polarized light reflectance can be produced with high productivity.

<Liquid crystal display device>
In the liquid crystal display device of the present invention, the liquid crystal panel having a liquid crystal layer sandwiched between a pair of substrates, the backlight unit, and the surface on which the protrusions are formed are on the backlight unit side, and no protrusions are formed. The wire grid polarizer of the present invention is arranged so that the side surface is on the viewing side of the liquid crystal display device.

The wire grid polarizer may be disposed on one surface of the liquid crystal panel, and is preferably disposed on the surface of the liquid crystal panel on the backlight unit side.
Further, the wire grid polarizer is arranged in an integrated state with one of the pair of substrates of the liquid crystal panel, as described in FIG. 15 of Japanese Patent Application Laid-Open No. 2006-139283. Alternatively, it is preferably integrated with the substrate of the liquid crystal panel on the backlight unit side.
The wire grid polarizer is arranged on the liquid crystal layer side of one of the pair of substrates of the liquid crystal panel, that is, inside the liquid crystal panel, as described in FIG. 14 of Japanese Patent No. 412388. Of the pair of substrates of the liquid crystal panel, it is preferably disposed on the liquid crystal layer side of the substrate on the backlight unit side.

The liquid crystal display device of the present invention preferably has an absorptive polarizer on the surface of the liquid crystal panel opposite to the side on which the wire grid polarizer is disposed, from the viewpoint of thinning.
The absorptive polarizer is more preferably disposed on the surface of the liquid crystal panel opposite to the backlight unit side.

  FIG. 7 is a cross-sectional view showing an example of the liquid crystal display device of the present invention. The liquid crystal display device 30 includes a liquid crystal panel 34 having a liquid crystal layer 33 sandwiched between a pair of substrates 31 and 32, a backlight unit 35, and the liquid crystal panel 34 on the backlight unit 35 side. And the absorptive polarizer 36 attached to the surface of the liquid crystal panel 34 opposite to the backlight unit 35 side.

The liquid crystal display device of the present invention described above has a high luminance because it has a wire grid type polarizer having a high degree of polarization and high p-polarized light transmittance.
In the liquid crystal display device of the present invention, the s-polarized reflectance of one surface (the surface on the side where the ridges are formed, that is, the surface) is high, and the other surface (the ridges are not formed). In the wire grid polarizer obtained by the manufacturing method of the present invention having a low s-polarized reflectance on the side surface (that is, the back surface), the surface on which the protrusions are formed becomes the backlight unit side, and the protrusions are formed. Since it is arranged so that the surface on the side that is not provided is the viewing side of the liquid crystal display device, a decrease in contrast can be suppressed.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.
Examples 1 to 30 are examples, and examples 31 to 34 are comparative examples.

(Projections and dimensions of each layer)
The dimensions of the ridges and the respective layers are the maximum values of the dimensions of the five ridges and the respective layers on the ridges in the transmission electron microscope image of the cross section of the wire grid polarizer (however, Dr1, Dr2, Db1, Da1 and Da2 were values defined above.) And the five maximum values were averaged.

(P-polarized light transmittance)
The p-polarized light transmittance was measured using an ultraviolet-visible spectrophotometer (manufactured by JASCO, V-7200). For the measurement, the attached polarizer is set between the light source and the wire grid polarizer so that the absorption axis is parallel to the major axis of the metal wire of the wire grid polarizer, and the surface of the wire grid polarizer is set. Polarization was made incident from the side (side where the ridges were formed) or the back side (side where the ridges were not formed). The measurement wavelengths were 450 nm, 550 nm, and 700 nm.
The p-polarized light transmittance was 40% or more as S, 35% or more and less than 40% as A, 30% or more and less than 35% as B, and less than 30% as X.

(S-polarized reflectance)
The s-polarized reflectance was measured using an ultraviolet-visible spectrophotometer (manufactured by JASCO, V-7200). In the measurement, the attached polarizer is set between the light source and the wire grid polarizer so that the absorption axis is perpendicular to the long axis of the metal fine wire of the wire grid polarizer, and the surface of the wire grid polarizer is set. Alternatively, the incident light was incident on the back surface at an angle of 5 degrees. The measurement wavelengths were 450 nm, 550 nm, and 700 nm.
The surface s-polarized reflectance was 40% or more as S, 35% or more and less than 40% as A, and 30% or more and less than 35% as B.
Further, the back surface s-polarized reflectance was less than 10% as S, 10% or more but less than 20% as A, 20% or more as B, and less than 20% as X.

(Degree of polarization)
The degree of polarization was calculated from the following equation.
Polarization degree = ((Tp−Ts) / (Tp + Ts)) ^0.5
Where Tp is the surface p-polarized light transmittance, and Ts is the surface s-polarized light transmittance.
The degree of polarization was 99.5% or more as S, 99.2% or more and less than 99.5% as A, 99% or more and less than 99.2% as B, and less than 99% as X.

(Luminance)
The luminance was measured by the following method.
A wire grid polarizer and a liquid crystal cell were stacked in this order on a 2-inch LED sidelight-type backlight. The wire grid type polarizer was installed so that the back side was the liquid crystal cell side. As the liquid crystal cell, a cell having an iodine polarizing plate only on the upper side was used.
A backlight and a liquid crystal cell were launched in the dark room. The display on the entire surface of the liquid crystal cell was white display, and the central luminance B31 after 10 minutes of lighting was measured at a viewing angle of 0.1 ° using a color luminance meter (manufactured by Topcon Corporation, BM-5AS). Subsequently, the entire surface of the liquid crystal cell was displayed as black, and the luminance B32 at that time was measured.
The same backlight was used, and a liquid crystal cell provided with iodine-based polarizing plates on the upper side and the lower side was stacked thereon. The backlight and the liquid crystal cell were started up in the dark room, and similarly, the central luminance B21 when the entire display of the liquid crystal cell was displayed as white was measured.
Using the value obtained by the above measurement, the luminance improvement rate was obtained from the following formula.
Luminance improvement rate = (B32−B21) / B21 × 100
The luminance improvement rate was 25% or more as S, 20% or more and less than 25% as A, 15% or more and less than 20% as B, and less than 15% as X.

(contrast)
Using the value obtained in the above measurement, the contrast was obtained from the following equation.
Contrast = B31 / B32
Contrast was 1000 or more as S, 500 or more and less than 1000 as A, 300 or more and less than 500 as B, and less than 300% as X.

(Measurement of absorption rate of light-absorbing material)
The absorption rate of the light-absorbing material was estimated by the following method.

(Nickel absorption rate)
A 5-inch quartz wafer having a thickness of 0.55 mm was set horizontally with respect to the target in a vacuum deposition apparatus (SEC-16CM, manufactured by Showa Vacuum Co., Ltd.), and the pressure was 1.2 × 10 ⁻⁴ Pa. Under the conditions, nickel was deposited on a quartz wafer so as to have a thickness of 60 nm.
Using a UV-visible spectrophotometer (manufactured by JASCO, V-7200), transmittance and reflectance at a wavelength of 550 nm of a quartz wafer having a nickel thin film formed on the upper surface were determined. A quartz wafer was used as a blank.
The absorption rate was estimated from the following equation.
Absorbance (%) of light having a wavelength of 550 nm = 100−Transmittance (%) of light having a wavelength of 550 nm−Reflectance (%) of light having a wavelength of 550 nm
Transmittance: 1%, Reflectance: 25%, Absorption rate: 74%

(Titanium absorption rate)
Absorption rate was estimated by the same method as nickel.
Transmittance: 0.5%, Reflectance: 18%, Absorptivity: 81.5%

(Chromium absorption rate)
Absorption rate was estimated by the same method as nickel.
Transmittance: 2%, Reflectance: 15%, Absorption rate: 87%

(Aluminum absorption rate)
Absorption rate was estimated by the same method as nickel.
Transmittance: 0%, reflectivity: 95%, absorption rate: 5%

(Preparation of photocurable composition)
To a 1000 mL four-necked flask equipped with a stirrer and a condenser,
60 g of monomer 1 (manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester A-DPH, dipentaerythritol hexaacrylate),
40 g of monomer 2 (manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester A-NPG, neopentyl glycol diacrylate),
4.0 g of photopolymerization initiator (manufactured by Ciba Specialty Chemicals, IRGACURE907),
Fluorine-containing surfactant (manufactured by Asahi Glass Co., Ltd., co-oligomer of fluoroacrylate (CH ₂ ═CHCOO (CH ₂ ) ₂ (CF ₂ ) ₈ F) and butyl acrylate), fluorine content: about 30% by mass, mass average molecular weight: About 3000) 0.1 g,
1.0 g of a polymerization inhibitor (Q1301 manufactured by Wako Pure Chemical Industries, Ltd.) and 65.0 g of cyclohexanone were added.

  The flask was stirred and homogenized for 1 hour at room temperature and in a light-shielded state. Next, 100 g (solid content: 30 g) of colloidal silica was slowly added while stirring in the flask, and the mixture was further homogenized by stirring for 1 hour while keeping the temperature of the flask at room temperature and light shielding. Next, 340 g of cyclohexanone was added, and the solution was stirred for 1 hour with the inside of the flask at room temperature and light-shielded to obtain a solution of the photocurable composition 1.

[Example 1]
The photocurable composition 1 was applied by spin coating to the surface of a 100 μm thick highly transparent polyethylene terephthalate (PET) film (Teijin DuPont, Teijin Tetron O3, 100 mm × 100 mm), and photocured with a thickness of 5 μm. A coating film of the composition 1 was formed.

  A quartz mold (area: 150 mm × 150 mm, pattern area: 100 mm × 100 mm, groove pitch Pp: a plurality of grooves formed in parallel with each other at a predetermined pitch through flat portions formed between the grooves. 140 nm, groove top width Dpb: 60 nm, groove bottom width Dpt: 20 nm, groove depth Hp: 200 nm, groove length: 100 mm, groove cross-sectional shape: substantially trapezoidal). The film was pressed against the coating film of the photocurable composition 1 at 25 MPa at 0.5 MPa (gauge pressure) so as to be in contact with the coating film of the composition 1.

  While maintaining this state, the PET film side was irradiated with light of a high-pressure mercury lamp (frequency: 1.5 kHz to 2.0 kHz, main wavelength light: irradiation energy at 255 nm, 315 nm and 365 nm, 365 nm: 1000 mJ) for 15 seconds, The photocurable composition 1 is cured, and a light-transmitting substrate 1 having a plurality of ridges corresponding to the grooves of the quartz mold and flat portions between the ridges (pitch pitch Pp of ridges: 140 nm, The bottom width Dpb: 60 nm, the top width Dpt of the ridge: 20 nm, the height Hp of the ridge: 200 nm, θ1 and θ2: 84 °) were produced. The quartz mold was slowly separated from the light transmissive substrate 1.

Using a vacuum vapor deposition apparatus (SEC-16CM, manufactured by Showa Vacuum Co., Ltd.) that can change the inclination of the light transmissive substrate 1 facing the vapor deposition source, the light transmissive substrate under the condition of pressure: 1.2 × 10 ⁻⁴ Pa to a first aspect of the first convex, the direction V shown in Table 1 as the first deposition to form a first absorbent layer by depositing a nickel at an angle theta ^R and deposition amount t, then the first A wire grid in which aluminum is deposited in the direction V, angle θ ^R and deposition amount t shown in Table 1 as the second deposition on the surface of the absorbent layer, a first reflective layer is formed, and a PET film is adhered to the back surface A type polarizer was obtained.
The deposition amount t was measured by a film thickness monitor using a crystal resonator as a film thickness sensor.

[Examples 2 and 3]
A wire grid polarizer was obtained in the same manner as in Example 1 except that the nickel forming the first absorption layer was changed to titanium or chromium.

[Example 4]
Except that the angle theta ^R for forming the first reflective layer and the angle shown in Table 1, to obtain a wire grid polarizer in the same manner as in Example 1.

[Example 5]
On the first side surface of the ridge of the light-transmitting substrate 1 produced in the same manner as in Example 1 under the pressure of 1.2 × 10 ⁻⁴ Pa, the direction V and the angle θ shown in Table 1 as the first deposition. ^A base layer is formed by vapor-depositing aluminum with ^R and a deposition amount t, and then nickel is deposited on the surface of the base layer with a direction V, an angle θ ^R and a deposition amount t shown in Table 1 as a second deposition. forming a first absorbent layer, then the first direction V shown in Table 1 as the third deposited absorber layer surface, aluminum is vapor deposition at an angle theta ^R and deposition amount t, the first reflective layer The wire grid type polarizer which formed and the PET film was stuck on the back surface was obtained.

[Examples 6 and 7]
A wire grid type polarizer was obtained in the same manner as in Example 5 except that the nickel forming the first absorption layer was changed to titanium or chromium.

[Example 8]
Except that the angle theta ^R for forming the first reflective layer and the angle shown in Table 1, to obtain a wire grid polarizer in the same manner as in Example 6.

[Example 9]
On the second side surface of the ridge of the light-transmitting substrate 1 produced in the same manner as in Example 1 under the pressure of 1.2 × 10 ⁻⁴ Pa, the direction V and the angle θ shown in Table 1 as the first vapor deposition. The second absorption layer is formed by depositing nickel with ^L and the deposition amount t, and then the direction V, the angle θ ^R and the deposition amount t shown in Table 1 as the second deposition on the first side surface of the ridge. form by depositing nickel to form the first absorbent layer, then the direction V shown in Table 1 as the third deposition, aluminum was vapor deposition at an angle theta ^R and deposition amount t, the first reflection layer at And the wire grid type polarizer with which the PET film was stuck on the back was obtained.

[Examples 10 and 11]
A wire grid polarizer was obtained in the same manner as in Example 9 except that nickel forming the first absorption layer and the second absorption layer was changed to titanium or chromium.

[Example 12]
Except that the angle theta ^R for forming the first reflective layer and the angle shown in Table 1, to obtain a wire grid polarizer in the same manner as in Example 10.

[Example 13]
On the first side surface of the ridge of the light-transmitting substrate 1 produced in the same manner as in Example 1 under the pressure of 1.2 × 10 ⁻⁴ Pa, the direction V and the angle θ shown in Table 1 as the first deposition. ^A base layer is formed by vapor-depositing aluminum with ^R and a deposition amount t, and then nickel is deposited with the direction V, angle θ ^L and deposition amount t shown in Table 1 as the second deposition on the second side surface of the ridge. the forming the second absorbent layer by depositing and then, the first absorbent layer by depositing the nickel in the direction V shown in Table 1 as the third deposited underlayer surface, the angle theta ^R and deposition amount t Then, aluminum is vapor-deposited on the first absorption layer surface in the direction V, angle θ ^R and vapor deposition amount t shown in Table 1 as the fourth vapor deposition, to form the first reflective layer, and on the back surface A wire grid polarizer with a PET film attached thereto was obtained.

[Examples 14 and 15]
A wire grid polarizer was obtained in the same manner as in Example 13 except that the nickel forming the first absorption layer and the second absorption layer was changed to titanium or chromium.

[Example 16]
Except that the angle theta ^R for forming the first reflective layer and the angle shown in Table 1, to obtain a wire grid polarizer in the same manner as in Example 14.

[Example 17]
On the first side surface of the ridge of the light-transmitting substrate 1 produced in the same manner as in Example 1 under the pressure of 1.2 × 10 ⁻⁴ Pa, the direction V and the angle θ shown in Table 1 as the first deposition. The first absorption layer is formed by evaporating nickel with ^R and the deposition amount t, and then the direction V, the angle θ ^L and the deposition amount t shown in Table 1 as the second deposition on the second side surface of the ridge. Then, nickel is vapor-deposited to form a second absorption layer, and then aluminum is vapor-deposited on the surface of the first absorption layer in the direction V, angle θ ^R and vapor deposition amount t shown in Table 1 to form the first absorption layer. A reflective layer is formed, and then aluminum is deposited on the second absorption layer surface in the direction V, angle θ ^L and deposition amount t shown in Table 1 to form the second reflective layer, and the PET film is formed on the back surface. Thus, a wire grid type polarizer attached with was obtained.

[Examples 18 and 19]
A wire grid polarizer was obtained in the same manner as in Example 17 except that nickel forming the first absorption layer and the second absorption layer was changed to titanium or chromium.

[Example 20]
A wire grid polarizer was obtained in the same manner as in Example 18 except that the angle θ ^L when forming the second reflective layer was changed to the angle shown in Table 1.
[Example 21]
As a mold, a quartz mold (area: 150 mm × 150 mm, pattern area: 100 mm × 100 mm, groove area) in which a plurality of grooves are formed in parallel with each other at a predetermined pitch through flat portions formed between the grooves. (Pitch Pp: 140 nm, groove width Dpb: 60 nm, groove depth Hp: 200 nm, groove length: 100 mm, groove cross-sectional shape: substantially isosceles triangle). Light transmissive substrate 2 having a plurality of ridges corresponding to the grooves of the quartz mold and flat portions between the ridges (ridge pitch Pp: 140 nm, ridge width Dpb: 60 nm, ridge height Hp : 200 nm, θ1 and θ2: 87 °).

  A wire grid polarizer was obtained in the same manner as in Example 1 except that the light-transmitting substrate 2 was used.

[Example 22]
Example 21 using the light-transmitting substrate 2 was prepared in the same manner as, except that the angle theta ^R for forming the first reflective layer was angle shown in Table 2, in the same manner as in Example 1 wire grid type polarization I got a child.

[Example 23]
A wire grid polarizer was obtained in the same manner as in Example 5 except that the light-transmitting substrate 2 produced in the same manner as in Example 21 was used.

[Example 24]
Example 21 using the light-transmitting substrate 2 was prepared in the same manner as, except that the angle theta ^R for forming the first reflective layer was angle shown in Table 2, a wire grid type polarization in the same manner as in Example 5 I got a child.

[Example 25]
A wire grid polarizer was obtained in the same manner as in Example 9 except that the light-transmitting substrate 2 produced in the same manner as in Example 21 was used.

[Example 26]
Example 21 using the light-transmitting substrate 2 was prepared in the same manner as, except that the angle theta ^R for forming the first reflective layer was angle shown in Table 2, a wire grid type polarization in the same manner as in Example 9 I got a child.

[Example 27]
A wire grid polarizer was obtained in the same manner as in Example 13 except that the light-transmitting substrate 2 produced in the same manner as in Example 21 was used.

[Example 28]
Example 21 using the light-transmitting substrate 2 was prepared in the same manner as, except that the angle theta ^R for forming the first reflective layer was angle shown in Table 2, a wire grid type polarization in the same manner as in Example 13 I got a child.

Example 29
A wire grid polarizer was obtained in the same manner as in Example 17 except that the light-transmitting substrate 2 produced in the same manner as in Example 21 was used.

[Example 30]
Using the light-transmitting substrate 2 produced in the same manner as in Example 21, the angle θ ^R when forming the first reflective layer and the angle θ ^L when forming the second reflective layer are the angles shown in Table 2. A wire grid polarizer was obtained in the same manner as in Example 17 except that.

Example 31
As a mold, a quartz mold (area: 150 mm × 150 mm, pattern area: 100 mm × 100 mm, groove area) in which a plurality of grooves are formed in parallel with each other at a predetermined pitch through flat portions formed between the grooves. A quartz mold is used in the same manner as in Example 1 except that the pitch Pp is 150 nm, the groove width Dpb is 60 nm, the groove depth Hp is 200 nm, the groove length is 100 mm, and the groove cross-sectional shape is rectangular. A light-transmitting substrate 3 having a plurality of ridges corresponding to the grooves and a flat portion between the ridges (ridge pitch Pp: 150 nm, ridge width Dpb: 60 nm, ridge height Hp: 200 nm, θ1 and θ2: 90 °).

Using the photocurable substrate 3 and the same vacuum deposition apparatus as in Example 1, while introducing 0.2 nm / sec of oxygen under the condition of pressure: 1.2 × 10 ⁻⁴ Pa, the light transmissive substrate 3 to a first aspect of the ridges of the first deposition, the direction shown in Table 2 V, at an angle theta ^R and deposition amount t, the first absorbent layer is evaporated while oxidizing the chromium (chromium oxide layer) Formed. Then, stop the introduction of oxygen, the first absorption layer plane direction V shown in Table 2, aluminum was vapor deposition at an angle theta ^R and deposition amount t, forming the first reflective layer (aluminum layer) A wire grid polarizer having a PET film attached to the back surface was obtained.
The chromium oxide layer and the outermost aluminum layer were formed only near the top of the ridge. The maximum width in the width direction of the ridges of the chromium oxide layer was 67 nm, and the height was 45 nm. The maximum width in the width direction of the ridges of the aluminum layer was 75 nm, and the height was 117 nm.

[Example 32]
Using the light-transmitting substrate 3 created in Example 31, using the same vacuum deposition apparatus as in Example 1, under the condition of pressure: 1.2 × 10 ⁻⁴ Pa, the first protrusion of the light-transmitting substrate 3 on the sides, as the first deposition, the direction shown in Table 2 V, aluminum was vapor deposition at an angle theta ^R and deposition amount t, forming the first reflective layer (aluminum layer). Then, while introducing oxygen 0.2 nm / sec, the said first direction V shown in Table 2 to the reflective layer surface on the angle theta ^R and deposition amount t at the first by depositing while oxidizing the chromium An absorption layer (chromium oxide layer) was formed, and a wire grid polarizer having a PET film attached to the back surface was obtained.
The aluminum layer and the outermost chromium oxide layer were formed only near the top of the ridge. The maximum width in the width direction of the ridges of the aluminum layer was 70 nm, and the height was 116 nm. The maximum width in the width direction of the ridge of the chromium oxide layer as the outermost layer was 74 nm, and the height was 20 nm.

[Example 33]
Example 21 using the light-transmitting substrate 2 was prepared in the same manner as, except that the angle theta ^R for forming the first absorbent layer was the angle shown in Table 2, in the same manner as in Example 1 wire grid type polarization I got a child.

[Example 34]
Pressure: the conditions of 1.2 × 10 -4 ^Pa, the ridges of the light-transmitting substrate 2 was prepared in the same manner as in Example 21, the direction shown in Table 2 V, the aluminum at an angle theta ^R and deposition amount t The first reflective layer is formed by vapor deposition, then nickel is vapor-deposited in the direction V, angle θ ^L and vapor deposition amount t shown in Table 2 to form the first absorption layer, and a PET film is pasted on the back surface. A worn wire grid polarizer was obtained.

[Measurement and evaluation]
About the wire grid type polarizer of Examples 1-34, each dimension of each layer was measured. The results are shown in Tables 3 and 4.
Moreover, the transmittance | permeability, the reflectance, the polarization degree, the brightness | luminance, and the contrast were measured about the wire grid type | mold polarizer of Examples 1-34. The results are shown in Tables 5 and 6.

The wire grid polarizer of the present invention is useful as a polarizer for an image display device such as a liquid crystal display device, a rear projection television, or a front projector.
The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2009-111487 filed on Apr. 30, 2009 are incorporated herein as the disclosure of the present invention. .

DESCRIPTION OF SYMBOLS 10 Wire grid type polarizer 12 Convex strip 13 Flat part 14 Light transmissive board | substrate 16 1st side surface 18 2nd side surface 19 Top part 20 1st reflection layer 22 1st absorption layer 24 Base layer 26 2nd absorption layer 28 Second Reflective Layer 30 Liquid Crystal Display Device 31 Substrate 32 Substrate 33 Liquid Crystal Layer 34 Liquid Crystal Panel 35 Backlight Unit 36 Absorption Polarizer

Claims (21)

A light-transmitting substrate in which a plurality of ridges whose width gradually narrows from the bottom to the top is formed on the surface in parallel with each other at a predetermined pitch via flat portions formed between the ridges. When,
A first reflective layer made of a metal material that covers the first side surface of the ridge;
1st absorption which consists of the light absorption material which absorbs light rather than the said metal material which exists between the said protruding item | line and the said 1st reflection layer, and coat | covers the whole surface of the 1st side surface of the said protruding item | line. A wire grid polarizer having a layer.   The wire grid type polarizer according to claim 1 whose thickness of said 1st absorption layer is 3-20 nm.   The wire according to claim 1, further comprising a base layer made of a metal material that exists between the ridge and the first absorption layer and covers the entire first side surface of the ridge. Grid type polarizer.   The wire grid polarizer according to any one of claims 1 to 3, further comprising a second absorption layer made of the light-absorbing material that covers the entire surface of the second side surface of the ridge.   The wire grid polarizer according to claim 4, further comprising a second reflective layer made of a metal material that covers a surface of the second absorption layer.   The wire grid type polarizer according to any one of claims 1 to 5, wherein a cross-sectional shape perpendicular to the length direction of the ridges is a triangle or a trapezoid.   The wire grid polarizer according to any one of claims 1 to 6, wherein the pitch Pp is 300 nm or less.   The wire grid polarizer according to any one of claims 1 to 7, wherein the thickness of the first reflective layer is 3 to 20 nm.   The ratio (Dpb / Pp) of the width Dpb of the bottom of the ridge and the total length Pp of the width of the flat portion formed between the Dpb and the ridge is 0.1 to 0.7. Item 9. A wire grid polarizer according to any one of Items 1 to 8. The width of the bottom of the ridge is Dpb, the total length of the Dpb and the width of the flat portion formed between the ridges is Pp, and the maximum thickness of the first reflective layer in the width direction of the ridge The wire grid polarizer according to any one of claims 1 to 9, wherein when the value is Dr1, Dr1 satisfies the following formula.
0.2 × (Pp−Dpb) ≦ Dr1 ≦ 0.5 × (Pp−Dpb)   The ratio (Hr1 / Hp) between the height Hr1 of the first reflective layer formed on the first side surface of the ridge and the height Hp of the ridge is 0.5 to 1.0. Item 11. A wire grid polarizer according to any one of Items 1 to 10. A light-transmitting substrate in which a plurality of ridges whose width gradually narrows from the bottom to the top is formed on the surface in parallel with each other at a predetermined pitch via flat portions formed between the ridges. A first reflective layer made of a metal material that covers the first side surface of the ridge, and the first side surface of the ridge that exists between the ridge and the first reflective layer. A wire grid polarizer having a first absorption layer made of a light-absorbing material that absorbs light more than the metal material.
Deposition of the light absorbing material from a direction substantially perpendicular to the length direction of the ridges and at an angle of 25 to 40 ° to the first side surface with respect to the height direction of the ridges. Is vapor-deposited under the condition of 3 to 20 nm to form the first absorption layer,
The metal material is deposited in a direction substantially perpendicular to the length direction of the ridges and at an angle of 25 to 50 ° to the first side surface with respect to the height direction of the ridges. The manufacturing method of the wire grid type polarizer which vapor-deposits on the conditions used as 15-50 nm, and forms the said 1st reflective layer.   The manufacturing method of the wire grid type polarizer of Claim 12 whose cross-sectional shape orthogonal to the length direction of the said protruding item | line is a triangle or a trapezoid.   The manufacturing method of the wire grid type polarizer of Claim 12 or 13 which consists of a photocurable resin or a thermoplastic resin, and is formed by the imprint method. A liquid crystal panel having a liquid crystal layer sandwiched between a pair of substrates;
A backlight unit;
The surface on which the ridge is formed is arranged on the backlight unit side, and the surface on which the ridge is not formed is arranged on the viewing side of the liquid crystal display device. A liquid crystal display device comprising the wire grid polarizer according to claim 1. It further has an absorptive polarizer,
The wire grid polarizer is disposed on one surface of the liquid crystal panel;
The liquid crystal display device according to claim 15, wherein the absorptive polarizer is disposed on a surface of the liquid crystal panel opposite to a side on which the wire grid polarizer is disposed. The wire grid polarizer is disposed on the surface of the liquid crystal panel on the backlight unit side,
The liquid crystal display device according to claim 16, wherein the absorption type polarizer is disposed on a surface of the liquid crystal panel opposite to the backlight unit side. It further has an absorptive polarizer,
The wire grid polarizer is integrated with one of the pair of substrates of the liquid crystal panel;
The liquid crystal display device according to claim 15, wherein the absorptive polarizer is disposed on a surface of the substrate of the liquid crystal panel opposite to a side on which the wire grid polarizer is integrated. The wire grid polarizer is integrated with the substrate of the liquid crystal panel on the backlight unit side;
The liquid crystal display device according to claim 18, wherein the absorption polarizer is disposed on a surface of the liquid crystal panel opposite to the backlight unit side. It further has an absorptive polarizer,
The wire grid polarizer is disposed on the liquid crystal layer side of one of the pair of substrates of the liquid crystal panel;
The liquid crystal display device according to claim 15, wherein the absorptive polarizer is disposed on a surface of the substrate of the liquid crystal panel opposite to a side on which the wire grid polarizer is disposed. The wire grid polarizer is disposed on the liquid crystal layer side of the substrate on the backlight unit side of the pair of substrates of the liquid crystal panel;
21. The liquid crystal display device according to claim 20, wherein the absorptive polarizer is disposed on a surface of the liquid crystal panel opposite to the backlight unit side.

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