JP2009086095A - Grid polarizer - Google Patents

Abstract

A grid polarizer excellent in durability, polarization separation performance, and the like is provided.
[Solution]
Grid-polarized light comprising a plate-like transparent substrate and a plurality of elongated and substantially parallel grid lines on at least one surface of the transparent substrate, and the entire surface of the grid lines and the transparent substrate are covered with a dielectric. In the child
The line connecting the cross-sectional area X in the direction perpendicular to the length of the grid line in the range surrounded by the transparent substrate, the grid line, and the line connecting the upper vertex of the grid line to the uppermost line and the upper vertex of the grid line is the highest. A grid polarizer in which the ratio of Y / X between the upper line and the cross-sectional area Y in the direction perpendicular to the length of the grid line in the space surrounded by the dielectric layer is 0.01 or more and 0.8 or less.
[Selection figure] None

Description

  The present invention relates to a grid polarizer, and more particularly to a grid polarizer excellent in durability, polarization separation performance, and the like.

  A grid polarizer is known as a polarizer whose polarization plane can be freely set. This is an optical member having a grid structure in which a large number of linear metals (wires) are arranged in parallel at a constant period. When such a metal grid structure is formed, when the period of the grid is shorter than the wavelength of the incident light, the polarization component parallel to the linear metal forming the grid structure is reflected and the vertical polarization component is Since it transmits, it functions as a polarizer that produces a single polarized light. It has been proposed that this grid polarizer is used as an optical component of an isolator in optical communication, and as a component for increasing light utilization and improving luminance in a liquid crystal display device.

  Since the grid structure of the grid polarizer is a very fine and delicate structure, a defect may occur in the grid structure when the surface is rubbed or scratched. In addition, oxygen and water vapor in the outside air may oxidize and degrade the grid, resulting in a decrease in polarization separation performance. Therefore, the grid polarizer is provided with a protective layer in order to protect the grid structure.

  Patent Document 1 describes an example in which an example in which a protective layer is provided on the entire upper surface of a grid structure is described. However, if a protective layer is provided on the entire upper surface of the grid structure, the durability is improved, but there is a problem that optical properties such as polarized light reflectance and polarized light transmittance are significantly inferior to those without the protective layer.

  On the other hand, Patent Document 2 shows a grid polarizer having a protective layer with a very thin protective layer. However, it is a problem whether sufficient durability can be maintained with such a thin protective layer.

Japanese Patent Laid-Open No. 2005-70465 US Pat. No. 7,158,302

  An object of the present invention is to provide a grid polarizer excellent in durability, polarization separation performance, and the like.

As a result of intensive studies to achieve the above object, the inventors of the present invention, in a grid polarizer covered with a dielectric,
A line connecting the average cross-sectional area X in the direction perpendicular to the length of the grid line and the upper vertex of the grid line in the range surrounded by the transparent substrate, grid line, and the line connecting the upper vertex of the grid line as the uppermost line Grid polarizer in which the ratio of Y / X between the uppermost line and the average cross-sectional area Y in the direction perpendicular to the length of the grid line in the space surrounded by the dielectric layer is 0.01 or more and 0.8 or less It has been found that a grid polarizer that is excellent in durability and that does not lose optical properties such as polarized light reflectance and polarized light transmittance can be obtained.

That is, the present invention includes the following aspects.
(1) A plate-like transparent substrate and at least one surface of the transparent substrate are formed with a plurality of elongated and substantially parallel grid lines, and the grid lines and the transparent substrate are covered with a dielectric. In grid polarizer,
A line connecting the average cross-sectional area X in the direction perpendicular to the length of the grid line and the upper vertex of the grid line in a range surrounded by the transparent base material, the grid line, and a line with the uppermost vertex connecting the grid line as the top line A grid having a Y / X ratio of 0.01 or more and 0.8 or less with respect to the average cross-sectional area Y in the direction perpendicular to the length of the grid line in the space surrounded by the uppermost line and the dielectric layer Polarizer.
(2) The transparent base material has a plurality of ridges that are elongated in a line on at least one surface and are arranged in parallel in a state of being separated from each other,
The grid polarizer described above, wherein grid lines are configured on top of the ridges.
(3) A metal layer exists between the ridges,
Average in the direction perpendicular to the length of the grid line in the range surrounded by the transparent substrate, the grid line formed on the top of the ridge, the metal layer, and the line connecting the upper vertices of the grid line. The ratio of Y / X between the line with the cross-sectional area X and the line connecting the upper vertices of the grid line as the top, and the average cross-sectional area Y in the direction perpendicular to the length of the grid line in the space surrounded by the dielectric layer The above-mentioned grid polarizer in which is 0.01 or more and 0.8 or less.
(4) Said grid polarizer which laminated | stacked the protective layer further on the dielectric material layer in order of the transparent base material, the grid line, the dielectric material layer, and the protective layer.
(5) The method for producing a grid polarizer described above, wherein the dielectric layer is formed by any one of sputtering, vapor deposition, and coating.

  The grid polarizer of the present invention not only has excellent optical characteristics, but also hardly undergoes oxidative degradation due to oxygen, water vapor, etc., and is less susceptible to distortion and scratches due to external force, and has excellent durability.

(Transparent substrate)
The transparent substrate used in the present invention is a plate-like material made of a transparent material such as a transparent resin or glass, preferably a plate-like material made of a transparent resin. The transparent resin preferably has a glass transition temperature of 60 to 200 ° C, more preferably 100 to 180 ° C from the viewpoint of processability. The glass transition temperature can be measured by differential scanning calorimetry (DSC).

Transparent resins include polycarbonate resin, polyethersulfone resin, polyethylene terephthalate resin, polyimide resin, polymethyl methacrylate resin, polysulfone resin, polyarylate resin, polyethylene resin, polyvinyl chloride resin, cellulose diacetate, cellulose triacetate, alicyclic ring And olefin polymers. Of these, alicyclic olefin polymers are preferred from the viewpoints of transparency, low hygroscopicity, dimensional stability, and processability.
Examples of the alicyclic olefin polymer include a cyclic olefin random multiple copolymer described in JP-A No. 05-310845, a hydrogenated polymer described in JP-A No. 05-97978, and JP-A No. 11-124429. And thermoplastic dicyclopentadiene-based ring-opening polymers and hydrogenated products thereof described in US Pat. No. 6,511,756.

The transparent resin used in the present invention contains coloring agents such as pigments and dyes, fluorescent brighteners, dispersants, heat stabilizers, light stabilizers, ultraviolet absorbers, antistatic agents, antioxidants, lubricants, solvents, etc. An agent may be appropriately blended.
A transparent base material is obtained by shape | molding the said transparent resin by a well-known method, for example. Examples of the molding method include a cast molding method, an extrusion molding method, and an inflation molding method.

The average thickness of the transparent substrate is usually 5 μm to 10 mm, preferably 20 to 500 μm, from the viewpoint of handleability.
The transparent substrate preferably has a light transmittance in the visible region of 400 to 700 nm of 80% or more.
Further, the transparent substrate, the retardation Re (Re = d × (n x -n y) defined in the value, n _x, n _y in-plane principal refractive index of the transparent substrate measured at the wavelength of 550 nm ( _nx ≧ _ny ); d is the average thickness of the transparent substrate.
The difference between the retardation Re at any two points in the plane (retardation unevenness) is preferably 10 nm or less, and more preferably 5 nm or less. When the retardation unevenness is large, the brightness of the display surface tends to vary when used in a liquid crystal display device.

In producing the grid polarizer of the present invention, a long transparent substrate is preferably used. “Long” means a material having a length of at least about 5 times the width, preferably a material having a length of 10 times or more, and specifically wound and stored in a roll shape. Or what has the length of the grade carried.
The width of the long transparent substrate is preferably 500 mm or more, more preferably 1000 mm or more. In the grid polarizer of the present invention, both ends in the width direction may be arbitrarily cut off (trimming) during the manufacturing process. In this case, the width | variety of the said transparent base material can be made into the dimension after cutting off both ends.

(Grid line)
The grid lines constituting the grid polarizing film of the present invention are linear metal layers that are laminated on at least one surface of the transparent substrate and extend substantially parallel to each other.
The material used for the metal layer (grid line) is preferably a conductive material, and specific examples include metals such as aluminum, indium, magnesium, rhodium, and tin.
The metal layer can be formed by physical vapor deposition (PVD method) of the material. The PVD method is a method of forming a film by evaporating and ionizing a vapor deposition material. Specifically, it can be appropriately selected from vacuum deposition, sputtering, ion plating (ion plating), ion beam deposition, and the like. Of these, vacuum deposition is preferred. The vacuum deposition method is a method of forming a thin film by heating and vaporizing or sublimating a deposition material in a vacuumed container and attaching it to the surface of a substrate placed at a remote position. Depending on the type of vapor deposition material and substrate, heating is performed by a method such as resistance heating, electron beam, high frequency induction, or laser.

  When a metal layer is formed on the transparent resin substrate having ridges by the PVD method, a metal layer is formed on the top of the ridges and the bottom of the grooves formed between the ridges (hereinafter referred to as convex in the present application). The metal layer formed on the top of the strip is referred to as metal layer A, and the metal layer is referred to as metal layer B at the bottom of the groove formed between the projections). The shape of the metal layer A formed on the top of the ridge in the cross section perpendicular to the longitudinal direction of the ridge is not particularly limited, and is usually rectangular, trapezoidal, circular, chevron or the like. The thickness of the metal layer A is not particularly limited, but is usually 20 to 500 nm, preferably 30 to 300 nm, and more preferably 40 to 200 nm. The width and length of the metal layer A are generally determined according to the shape of the top surface of the ridge.

  The shape of the metal layer B formed at the bottom of the groove formed between the ridges in the cross section perpendicular to the longitudinal direction of the ridges is not particularly limited, and is usually a rectangle, a trapezoid, a circle, a mountain, or the like. The thickness of the metal layer B is usually 20 to 500 nm, preferably 30 to 300 nm. The width and length of the metal layer B are generally determined according to the shape of the bottom surface of the groove.

Particularly preferred for the shape of the metal layer B is the maximum thickness H ₁ in the cross section perpendicular to the longitudinal direction of the ridge-shaped protrusions of the metal layer B and both ends of the cross-section perpendicular to the longitudinal direction of the ridge-shaped protrusions of the metal layer B. The relationship of the minimum thickness H ₂ of the part is 0.6 ≧ H ₂ / H ₁
In particular, the shape in the cross section perpendicular to the longitudinal direction of the ridge-shaped convex portion of the metal layer B is such that the shape is high in the center and low on both sides (FIG. 4), and has excellent broadband properties and polarization separation performance. Is still preferable.

  A part of the metal layer formed on the uneven surface as described above is preferably removed by wet etching. The part of the metal layer to be removed includes a portion formed on the side wall of the ridge, a portion protruding from the top width of the ridge, and the like. The wet etching includes at least a step of bringing an etching solution into contact with the metal layer, a step of washing with a rinse solution, and a step of removing the rinse solution.

  Before the step of bringing the etching solution into contact with the metal layer, a mask layer may be provided on a portion of the metal layer that is desired not to be removed. An inorganic oxide film is usually used for the mask layer. The mask layer can reduce the thickness of the metal layer by reducing the decrease in the thickness of the metal layer.

  The inorganic oxide for masking is not particularly limited as long as it can withstand wet etching described later, and examples thereof include compounds such as silicon oxide, silicon nitride, silicon carbide, and silicon nitride oxide. Of these, silicon oxide is particularly preferable. The thickness of the inorganic oxide film to be laminated is not particularly limited, but is usually 1 to 100 nm, preferably 2 to 50 nm, more preferably 3 to 20 nm. The inorganic oxide film can be formed by a PVD method.

(Dielectric layer)
The grid lines and transparent substrate of the grid polarizer of the present invention are directly covered with a dielectric. In this application, being covered with a dielectric means that it is completely covered so that grid lines and a transparent substrate do not appear on the surface. The dielectric is preferably transparent, and examples thereof include inorganic oxides, inorganic nitrides, porous materials, transparent resins, etc. Among them, inorganic oxides and transparent resins are preferable. Specifically, silicon oxide, silicon nitride, silicon carbide, aluminum oxide, titanium oxide and the like can be used, and among these, silicon oxide is particularly preferable.

A line (line indicated by 316 in FIGS. 5 and 6) having a line connecting the dielectric layer and the top vertex of the grid line as the uppermost part and a space surrounded by the dielectric layer (314 in FIGS. 5 and 6) The average cross-sectional area Y of the transparent substrate, the grid line, and a range surrounded by a line (line indicated by 316 in FIG. 5 and FIG. 6) with the line connecting the upper vertices of the grid line as the uppermost (FIG. 5, FIG. Regarding the relationship with the average cross-sectional area X in the direction perpendicular to the length of the grid lines in 313) in FIG. 6, the ratio of Y / X is 0.01 or more and 0.8 or less.
In addition, when it has the metal layers A and B at the same time in the present application, not only the metal layer A but also the metal layer B functions as a grid line, but in calculating the average cross-sectional area of the present application, the metal layer A is used as a reference grid line. A cross-sectional area is obtained (see FIG. 7). That is, the line (line indicated by 316 in FIG. 7) that connects the upper vertices of the grid lines is the line that connects the upper vertices of the metal layers A, and the range for obtaining the average cross-sectional area X Is a range (313 in FIG. 7) surrounded by a line having the top of the line connecting the transparent substrate, grid line (metal layer A), metal layer B and the upper vertex of the grid line, and the average cross-sectional area Y is The space for obtaining is a space (314 in FIG. 7) surrounded by a dielectric layer and a line having the uppermost line connecting the upper vertices of the grid lines.

When the ratio of Y / X is smaller than 0.01, the characteristics in the short wavelength region are remarkably inferior, which is not desirable. In order to have sufficient optical properties, it is desirably 0.03 or more, more preferably 0.05 or more.
Y / X is a numerical value less than 1 because a dielectric layer is present. However, in order to obtain sufficient durability, although it depends on the material, a numerical value of 0.8 or less, preferably 0.7 or less, more preferably 0.68 or less is desirable.

The cross-sectional area X in the direction perpendicular to the length of the grid line in the range surrounded by the transparent substrate, the grid line, and the line connecting the upper vertex of the grid line as the uppermost line, and the line connecting the upper vertex of the grid line Measurement of the cross-sectional area Y in the direction perpendicular to the length of the grid line in the space surrounded by the uppermost line and the dielectric layer is performed by cutting the grid polarizer perpendicularly in the longitudinal direction with a microtome, etc. This is done by measuring and calculating the uneven shape and the dimensions of the metal layer and dielectric layer using an electron micrograph of the cross section. The average cross-sectional area is a range in which the observation image is 10 μm in length by randomly sampling several points 5 mm or more apart from at least 10 mm or more from the end on the line cut perpendicularly in the longitudinal direction. The average cross-sectional area of the cross section inside is obtained.

  The dielectric layer can be formed by sputtering, vapor deposition, coating, or the like. By appropriately changing the conditions, a dielectric layer having a preferable Y / X value can be formed. For example, in the case of sputtering, a dielectric layer having a desired Y / X value can be formed by appropriately adjusting the output, gas type, pressure, temperature, time, and the like. There is no particular limitation on the shape of the cross section perpendicular to the longitudinal direction of the ridge-shaped protrusions in the space between the ridge-shaped protrusions after the dielectric is formed, but it is usually a triangle, rectangle, trapezoid, or circle.

In the grid polarizing film obtained by the production method of the present invention, a protective layer may be further laminated directly or via another layer on the surface on which the dielectric layer is formed.
The protective layer is not particularly limited by its material, but is preferably made of a transparent material. Examples of the transparent material include glass, a porous material, and a transparent resin. Of these, those made of transparent resin are particularly preferred. The transparent resin can be appropriately selected from those shown as constituting the aforementioned transparent resin film.
The average thickness of the protective layer is usually 5 μm to 1 mm, preferably 20 to 200 μm, from the viewpoint of handleability. The protective layer preferably has a light transmittance of 80% or more in the visible light region having a wavelength of 400 to 700 nm.

The protective layer is the value defined by the retardation Re (Re = d × measured at that wavelength _{550nm (n x -n y),} n x, n y plane principal refractive index of the protective layer (n _x ≧ _ny ); d is the average thickness of the protective layer. The difference between the retardation Re at any two points in the plane (retardation unevenness) is preferably 10 nm or less, and more preferably 5 nm or less. When the retardation unevenness is large, the brightness of the display surface tends to vary when used in a liquid crystal display device.

  The grid polarizer of the present invention has a property of transmitting one of orthogonal linearly polarized light and reflecting the other. Utilizing the property of separating such linearly polarized light into transmitted light and reflected light, the grid polarizer of the present invention is used as it is as an element for improving the luminance of a liquid crystal display device, or other optical elements (polarizer, phase difference). In combination with a plate or the like.

  EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

(Visual observation of transmitted light through grid polarizing film)
The transmitted light of the produced grid polarizing film was visually observed.

(Measurement of polarization transmittance and polarization reflectance)
The obtained grid polarizing film was punched into a predetermined shape to obtain a single-wafer grid polarizing film. The polarization transmittance and polarization reflectance of the grid polarizing film with respect to wavelengths of 450 nm, 550 nm, and 650 nm were measured using a spectrophotometer V-570 (manufactured by JASCO).
Note that linearly polarized light is used for the measurement of the polarization transmittance and the polarization reflectance. In the case of the measurement of the polarization transmittance, the transmission axis of the grid polarizing film is parallel to the polarization of the incident light, and the polarization reflectance is measured. In this case, the transmission axis of the grid polarizing film and the polarization of incident light were orthogonal to each other, and the reflectance at an incident angle of 5 ° was measured.

(Hot water test)
The grid polarizer film was immersed in warm water at 80 ° C. for 1 hour, and then dried, and measured for polarization transmittance and polarization reflectance.

Production Example 1
A focused ion beam processing device SMI3050 (manufactured by Seiko Instruments Inc.) is used on a 0.2 mm × 1 mm surface of a rectangular solid single crystal diamond of 0.2 mm × 1 mm × 1 mm brazed to a SUS shank of 8 mm × 8 mm × 60 mm. Then, focused ion beam processing using an argon ion beam was performed, and a rectangular pattern with a pitch of 180 nm was engraved into a groove having a width of 90 nm and a length of 80 nm parallel to a side having a length of 1 mm to produce a cutting tool.
A cutting tool in which a nickel-phosphorous electroless plating with a thickness of 100 μm is applied to the entire curved surface of a cylindrical stainless steel SUS430 having a diameter of 200 mm and a length of 150 mm, and then a linear projection formed previously, and a precision cylindrical grinder By using S30-1 (manufactured by Studer), cutting a linear protrusion having a width of 90 nm, a height of 80 nm, and a pitch of 180 nm in a direction parallel to the circumferential end surface of the cylinder on the nickel-phosphorous electroless plating surface A transfer roll was obtained. In addition, the preparation of the cutting tool by focused ion beam processing and the cutting of the nickel-phosphorous electroless plating surface are performed at a temperature of 20.0 ± 0.2 ° C. and 0.5H by a vibration control system (manufactured by Showa Science).
The measurement was performed in a constant-temperature low-vibration chamber in which the vibration displacement of z or more was controlled to 10 μm or less.

Using a nip roll composed of a rubber roll having a diameter of 70 mm and a transfer apparatus using the transfer roll, the transfer roll surface temperature is 160 ° C., the nip roll surface temperature is 100 ° C., the film transport tension is 0.1 kgf / mm ² , and the nip pressure. Was transferred onto the surface of a cycloolefin polymer film (ZF-14, manufactured by Nippon Zeon Co., Ltd.) having a thickness of 100 μm under the condition of 0.5 kgf / mm, and wound into a roll. The obtained long film was cut into a predetermined size, an observation section for TEM was prepared using a micro sampling device of a focused ion beam processing observation device FB-2100 (manufactured by Hitachi, Ltd.), and a transmission electron microscope H-7500 ( As a result of observing the film cross section at Hitachi, Ltd., the pattern on the film had a rectangular corrugated shape with an average width of openings of 90 nm, an average height of 80 nm, and an average pitch of 180 nm.

On the pattern forming surface of the long patterned film, SiO ₂ was obliquely deposited from the direction of 70 ° from the vertical direction of the film by sputtering under the condition of an output of 400 W in the presence of argon gas, and then the same from the opposite side After forming the film obliquely from the direction of 70 degrees, aluminum was formed from the vertical direction of the film by vacuum deposition and wound into a roll.
Etching with composition (acid component equivalent concentration: 81.6%) consisting of 5.2% nitric acid, 73.0% phosphoric acid, 3.4% acetic acid and the balance water in an etching tank equipped with a heating device and a stirring device The solution is stored, and the film laminated with aluminum is immersed for 30 seconds in an etching bath in which the temperature of the etching solution is adjusted to 33 ° C., then dried at 120 ° C. for 5 minutes, and wound into a roll to obtain a long length. A grid polarizing film was manufactured.

A long grid polarizing film is cut into a predetermined size, a TEM observation cross section is prepared using a micro sampling device of a focused ion beam processing observation device FB-2100 (manufactured by Hitachi, Ltd.), and a transmission electron microscope H-7500 ( When the cross section of the film was observed by Hitachi, Ltd., it was found that the shape was as shown in FIG. The average thickness of aluminum formed on the ridge-shaped convex portion was 70 nm, the average maximum thickness H ₁ of aluminum formed in the groove portion was 60 nm, and the average of the minimum thickness H ₂ at both ends was 4 nm. . The average cross-sectional area X in the direction perpendicular to the length of the grid line was 10620 nm ² .

Example 1
The grid polarizer produced in Production Example 1 was subjected to SiO ₂ sputtering for 140 seconds under the conditions of an output of 400 W, an argon flow rate of 25 sccm, and a film forming pressure of 0.80 Pa, and a dielectric layer was laminated on the surface. The average thickness was 40 nm from the top of the metal layer formed in the groove, and the average cross-sectional area Y of the vertical cross section was 531 nm ² . Y / X was 0.05.

Example 2
The grid polarizer produced in Production Example 1 was subjected to SiO ₂ sputtering for 30 seconds under the conditions of an output of 400 W, an argon flow rate of 25 sccm, and a film forming pressure of 0.80 Pa, and a dielectric layer was laminated on the surface. The average thickness was 10 nm from the top of the metal layer formed in the groove. The average sectional area Y of the vertical section was 7124 nm ² . Y / X was 0.67.

Example 3
The grid polarizer produced in Production Example 1 was subjected to SiO ₂ sputtering for 65 seconds under the conditions of an output of 400 W, an argon flow rate of 25 sccm, and a film forming pressure of 0.80 Pa, and a dielectric layer was laminated on the surface. The average thickness was 20 nm from the top of the metal layer formed in the groove. The average sectional area Y of the vertical section was 4278 nm ² . Y / X was 0.40.

Example 4
A 50% aqueous solution of nitrilotris (methylene) trisulfonic acid was further applied to the grid polarizer produced in Production Example 2, and dried at a temperature of 60 ° C. for 20 minutes. The average sectional area Y of the vertical section was 2970 nm ² . Y / X was 0.30.

Comparative Example 1
The grid polarizer produced in Production Example 1 was subjected to SiO ₂ sputtering for 300 seconds under the conditions of an output of 400 W, an argon flow rate of 25 sccm, and a film forming pressure of 0.80 Pa, and a dielectric layer was laminated on the surface. The space between the ridges was completely filled with a dielectric. The average thickness was 100 nm from the top of the metal layer formed in the groove. Y was 0 and Y / X was 0.

Comparative Example 2
The grid polarizer produced in Production Example 1 was subjected to SiO 2 sputtering for 10 seconds under the conditions of an output of 400 W, an argon flow rate of 25 sccm, and a film forming pressure of 0.80 Pa, and a dielectric layer was laminated on the surface. The average thickness was 5 nm from the top of the light-absorbing layer between the ridges. The average cross-sectional area Y of the vertical section was 8791 nm2. Y / X was 0.83.

Comparative Example 3
The grid polarizer produced in Production Example 1 was used for the next evaluation without any treatment. Since nothing was laminated on the light absorbing layer, Y / X was 1.00.

Tables 1 to 4 show the polarizing transmittance and polarizing reflectance of the grid polarizing film with respect to the wavelengths of (a) 450 nm, (b) 550 nm, and (c) 650 nm before and after the hot water test for Examples 1 to 4 and Comparative Examples 1 to 3. .
The criteria for determination are as follows.
Optical property determination: ○ 60% or more of polarized light transmittance and polarized light reflectance at each wavelength before being immersed in warm water at 80 ° C for 1 hour
If you have less than 60% ×
Durability determination: After immersing the grid polarizer film in warm water at 80 ° C. for 1 hour,
Polarized transmittance and polarized light reflectance decreased by 10% or more than before immersion in warm water.
The one whose polarization transmittance and polarization reflectance are less than 10% lower than before immersion in hot water

  As shown in Table 1, in Examples 1 to 4, both the polarization transmittance and the polarization reflectance were good, the values were maintained even after the hot water test, and it was found to have durability. On the other hand, it was found that Comparative Example 1 had durability in the hot water test, but in terms of optical characteristics, it was found that there was a problem in the polarization transmittance and polarization reflectance on the short wavelength side. In Comparative Examples 2 and 3, the optical characteristics were good, but the value could not be maintained after the hot water test, and it was found that there was a problem in durability.

It is a perspective conceptual diagram which shows one embodiment of a grid polarizer. It is a perspective conceptual diagram which shows another embodiment of a grid polarizer. . It is a conceptual diagram which shows the cross section of the grid polarizer of FIG. It is a conceptual diagram for demonstrating one embodiment of the shape of the metal layer B formed in the groove | channel. It is sectional drawing which shows one embodiment of the grid polarizer of this invention. It is sectional drawing which shows one embodiment of the grid polarizer of this invention. It is sectional drawing which shows one embodiment of the grid polarizer of this invention.

Explanation of symbols

310: Transparent substrate 311: Grid line 311 ′: Metal layer 312: Space before dielectric layer lamination 313: Transparent substrate, grid line formed on top of the ridge, metal layer, and upper vertex of the grid line A section 314 in a direction perpendicular to the length of the grid line in a range surrounded by a line connecting the uppermost points of the grid lines and a dielectric layer surrounded by the dielectric layer Section 315 in the direction perpendicular to the length of the grid line of the space to be measured: Dielectric layer 316: Line connecting the upper vertices of the grid line

H1: Maximum thickness of metal layer B H2: Minimum thickness of metal layer B

Claims (5)

A plate-shaped transparent substrate and a grid polarizer in which a plurality of elongated and substantially parallel grid lines are formed on at least one surface of the transparent substrate, and the grid lines and the transparent substrate are covered with a dielectric. In
A line connecting the average cross-sectional area X in the direction perpendicular to the length of the grid line and the upper vertex of the grid line in a range surrounded by the transparent base material, the grid line, and a line with the uppermost vertex connecting the grid line as the top line A grid having a Y / X ratio of 0.01 or more and 0.8 or less with respect to the average cross-sectional area Y in the direction perpendicular to the length of the grid line in the space surrounded by the uppermost line and the dielectric layer Polarizer. The transparent base material has a plurality of ridges that are elongated in a line on at least one surface and arranged in parallel in a state of being separated from each other,
The grid polarizer of Claim 1 with which the grid line was comprised on the top of the said protruding item | line. There is a metal layer between the ridges,
Average in the direction perpendicular to the length of the grid line in the range surrounded by the transparent substrate, the grid line formed on the top of the ridge, the metal layer, and the line connecting the upper vertices of the grid line. The ratio of Y / X between the line with the cross-sectional area X and the line connecting the upper vertices of the grid line as the top, and the average cross-sectional area Y in the direction perpendicular to the length of the grid line in the space surrounded by the dielectric layer The grid polarizer according to claim 2, wherein is not less than 0.01 and not more than 0.8.   The grid polarizer in any one of Claims 1-3 which laminated | stacked the protective layer further on the dielectric material layer in order of the transparent base material, the grid line, the dielectric material layer, and the protective layer.   The method for manufacturing a grid polarizer according to any one of claims 1 to 4, wherein the dielectric layer is formed by any one of sputtering, vapor deposition, and coating.

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