Polarizing element and liquid crystal projector

Abstract

A polarizing plate having a desired extinction ratio in a visible light region and light resistance against intense light, and a liquid crystal projector using the above polarizing plate are provided. A polarizing element includes a substrate transparent to visible light, and inorganic particle layers in each of which inorganic particles are linearly disposed, the inorganic particle layers being disposed on the substrate at predetermined intervals to form a wire grid structure, the inorganic particles each have an elliptical shape having a major axis of the inorganic particles in the disposed direction and minor axis in a direction perpendicular thereto.

The invention is claimed as follows: 
     
       1. A polarizing element comprising:
 a first polarizing element including a first substrate transparent to visible light, and 
 first inorganic particle layers in each of which first inorganic particles are linearly disposed on the first substrate, the first inorganic particle layers being disposed on the first substrate at predetermined intervals to form a wire grid structure, 
 wherein the first inorganic particles each have an elliptical shape with a major axis in a disposed direction and a minor axis in a direction perpendicular thereto, 
 wherein the first polarizing element further includes convex portions, which are made of a material transparent to visible light and which extend in one direction, provided on the first substrate, 
 wherein the first inorganic particle layers are each provided on a top part or at least one of sidewall parts of each of the convex portions; and 
 a second polarizing element including a second substrate transparent to visible light, and 
 second inorganic particle layers in each of which second inorganic particles are linearly disposed on the second substrate, the second inorganic particle layers being disposed on the second substrate at predetermined intervals to form a wire grid structure, 
 wherein the second inorganic particles each have an elliptical shape anisotropic properties in which a diameter with a major axis in a disposed direction is long and a diameter minor axis in a direction perpendicular thereto is short, 
 wherein the second polarizing element further includes reflection layers of strip-shaped thin films, which are made of a metal and which extend in one direction, provided on the second substrate at predetermined intervals;, and first dielectric layers provided on the reflection layers, 
 wherein the second inorganic particle layers are provided on the first dielectric layers at positions corresponding to those of the strip-shaped thin films, and 
 wherein the first and second substrates are adhered to each other at rear surfaces thereof. 
 
     
     
       2. The polarizing element according to  claim 1 ,
 wherein a refractive index of the first inorganic particles in the disposed direction is larger than that of the first inorganic particles in the direction perpendicular to the disposed direction. 
 
     
     
       3. The polarizing element according to  claim 2 ,
 wherein an extinction coefficient of the first inorganic particles in the disposed direction is larger than that of the first inorganic particles in the direction perpendicular thereto. 
 
     
     
       4. The polarizing element according to  claim 1 ,
 wherein the first inorganic particle layers are formed by an oblique sputtering method. 
 
     
     
       5. The polarizing element according to  claim 1 ,
 wherein the first inorganic particles include a single element selected from the groups consisting of: Al, Ag, Cu, Au, Mo, Cr, Ti, W, Ni, Fe, Si, Ge, Te, and Sn, an alloy thereof, or a silicide semiconductor material. 
 
     
     
       6. The polarizing element according to  claim 1 ,
 wherein the first inorganic particles include a semiconductor material having a bandgap energy of 3.1 eV or less. 
 
     
     
       7. The polarizing element according to  claim 1 ,
 wherein the first inorganic particle layers have a thickness of 200 nm or less. 
 
     
     
       8. The polarizing element according to  claim 1 ,
 wherein the second substrate is processed by a rubbing treatment so that the direction of the rubbing treatment corresponds to the disposed direction of the first inorganic particles, 
 the polarizing element further comprising antireflection layers of inorganic particles having shape anisotropic properties, the antireflection layers being provided on the surface of the second substrate so that the direction of the inorganic particles corresponds to the disposed direction of the first inorganic particles. 
 
     
     
       9. The polarizing element according to  claim 1 ,
 further comprising 
 second dielectric layers, the second inorganic particle layers and the second dielectric layers forming laminates, 
 wherein at least one of the laminates is provided on each of the first inorganic particle layers. 
 
     
     
       10. The polarizing element according to  claim 1 , further comprising a polarizing element protective layer transparent to light in a service bandwidth as an outermost surface. 
     
     
       11. A liquid crystal projector comprising:
 a lamp; 
 a liquid crystal panel; and 
 a polarizing element including a substrate transparent to visible light; and 
 first inorganic particle layers in each of which first inorganic particles are linearly disposed on the substrate, the first inorganic particle layers being disposed on the substrate at predetermined intervals to form a wire grid structure, 
 wherein the first inorganic particles each have an elliptical shape with a major axis in a disposed direction and a minor axis in a direction perpendicular thereto, 
 wherein the first polarizing element further includes convex portions, which are made of a material transparent to visible light and which extend in one direction, provided on the first substrate, 
 wherein the first inorganic particle layers are each provided on a top part or at least one of sidewall parts of each of the convex portions; and 
 a second polarizing element including a second substrate transparent to visible light, and 
 second inorganic particle layers in each of which second inorganic particles are linearly disposed on the second substrate, the second inorganic particle layers being disposed on the second substrate at predetermined intervals to form a wire grid structure, 
 wherein the second inorganic particles each have an elliptical shape anisotropic properties in which a diameter with a major axis in a disposed direction is long and a diameter minor axis in a direction perpendicular thereto is short, 
 wherein the second polarizing element further includes reflection layers of strip-shaped thin films, which are made of a metal and which extend in one direction, provided on the second substrate at predetermined intervals;, and first dielectric layers provided on the reflection layers, 
 wherein the second inorganic particle layers are provided on the first dielectric layers at positions corresponding to those of the strip-shaped thin films, and 
 wherein the first and second substrates are adhered to each other at rear surfaces thereof. 
 
     
     
       12. A polarizing element comprising:
 a substrate transparent to visible light;   reflection layers including strip-shaped thin films, which include a metal and which extend in one direction, provided on the substrate at predetermined intervals;   dielectric layers formed on the reflection layers;   inorganic particle layers in each of which inorganic particles are linearly disposed; and   a polarizing element protective layer transparent to light in a service bandwidth formed as an outermost surface using SiO 2 ,   wherein the inorganic particle layers are formed at positions corresponding to positions of the strip-shaped thin films, on at least one side surface part of the strip-shaped thin films on the dielectric layers, and   wherein the polarizing element has a wire grid structure having a longitudinal direction which is a same direction in which the inorganic particles are linearly disposed.   
     
     
       13. A polarizing element comprising:
 a substrate transparent to visible light;   reflection layers including strip-shaped thin films, which include a metal and which extend in one direction, provided on the substrate at predetermined intervals;   dielectric layers formed on the reflection layers; and   inorganic particle layers in each of which inorganic particles are linearly disposed,   wherein the inorganic particle layers are formed at positions corresponding to positions of the strip-shaped thin films, on at least one side surface part of the strip-shaped thin films on the dielectric layers,   wherein the polarizing element has a wire grid structure having a longitudinal direction which is a same direction same in which the inorganic particles are linearly disposed,   wherein the substrate includes any one of glass, sapphire, and quartz, and   wherein the substrate has a concave-convex member formed thereon, which has a pitch of 0.5 μm or less, a line width of 0.25 μm or less, a depth of 1 nm or more.   
     
     
       14. A polarizing element comprising:
 a substrate transparent to visible light;   reflection layers including strip-shaped thin films, which include a metal and which extend in one direction, provided on the substrate at predetermined intervals;   dielectric layers formed on the reflection layers;   inorganic particle layers in each of which inorganic particles are linearly disposed; and   a polarizing element protective layer transparent to light in a service bandwidth formed as an outermost surface using SiO 2 ,   wherein the inorganic particle layers are formed at positions corresponding to positions of the strip-shaped thin films, on both side surface parts of top parts of the strip-shaped thin films on the dielectric layers, and   wherein the polarizing element has a wire grid structure having a longitudinal direction which is a same direction in which the inorganic particles are linearly disposed.   
     
     
       15. A polarizing element comprising:
 a substrate transparent to visible light;   reflection layers including strip-shaped thin films, which include a metal and which extend in one direction, provided on the substrate at predetermined intervals;   dielectric layers formed on the reflection layers; and   inorganic particle layers in each of which inorganic particles are linearly disposed,   wherein the inorganic particle layers are formed at positions corresponding to positions of the strip-shaped thin films, on both side surface parts of top parts of the strip-shaped thin films on the dielectric layers,   wherein the polarizing element has a wire grid structure having a longitudinal direction which is a same direction in which the inorganic particles are linearly disposed,   wherein the substrate includes any one of glass, sapphire, and quartz, and   wherein the substrate has a concave-convex member formed thereon, which has a pitch of 0.5 μm or less, a line width of 0.25 μm or less, a depth of 1 nm or more.   
     
     
       16. A wire grid polarizing element comprising:
 a substrate transparent to visible light; and   reflection layers including strip-shaped thin films, which include a metal and which extend in one direction, provided on the substrate at predetermined intervals,   a dielectric layer provided on the reflection layers, and   an inorganic particle layer being disposed linearly,   wherein the inorganic particle layer is formed on both side surfaces of top parts of the dielectric layer, and the inorganic particle layer is disposed in a same direction in which the reflection layers extend.   
     
     
       17. The wire grid polarizing element according to claim 16, further comprising antireflection layers being provided between the substrate and the reflection layers. 
     
     
       18. The wire grid polarizing element according to claim 16, wherein the wire grid polarizing element further includes convex portions, wherein the pitch of the convex portions is less than or equal to 0.5 μm, and the line width of the convex portions is less than or equal to 0.25 μm, and the height of the convex portions is not less than 1 nanometer. 
     
     
       19. A liquid crystal projector comprising:
 a liquid crystal panel;   an incident polarizing plate;   an emission polarizing plate;   wherein the emission polarizing plate comprising:   a substrate transparent to visible light;   reflection layers including strip-shaped thin films, which include a metal and which extend in one direction, disposed provided on the substrate at predetermined intervals;   a dielectric layer provided on the reflection layers, and   an inorganic particle layer being disposed linearly,   wherein the inorganic particle layer is formed on the dielectric layer, and the inorganic particle layer is disposed in a same direction in which the reflection layers extend, and   wherein the inorganic particle layer of the emission polarizing plate is disposed to face the liquid crystal panel.   
     
     
       20. The liquid crystal projector according to claim 19, wherein the incident polarizing plate includes the inorganic particle layer that is disposed to face the liquid crystal panel. 
     
     
       21. The liquid crystal projector according to claim 19, wherein the liquid crystal projector is a transmission projector. 
     
     
       22. A liquid crystal display comprising:
 a liquid crystal panel;   a polarizing plate;   wherein the polarizing plate comprising:
 a substrate; 
 a plurality of reflection layers disposed at a predetermined interval, wherein the reflection layers extend in a first direction and include a metal material; 
 a dielectric layer includes a dielectric layer material selected from the group consisting of SiO2, Al2O3, and MgF2; and 
 an inorganic particle layer includes a plurality of inorganic particles having an anisotropic shape including a first inorganic particle length in the first direction that is greater than a second inorganic particle length in a second direction along the first surface perpendicular to the first direction, wherein the substrate has a concave-convex member formed thereon, which has a pitch of 0.5 μm or less, a line width of 0.25 μm or less, a depth of 1 nm or more. 
   
     
     
       23. A liquid crystal display comprising:
 a liquid crystal panel;   a polarizing plate;   wherein the polarizing plate comprising:
 a substrate; 
 a plurality of reflection layers disposed at a predetermined interval, wherein the reflection layers extend in a first direction and include a metal material; 
 a dielectric layer includes a dielectric layer material selected from the group consisting of SiO2, Al2O3, and MgF2; and 
 an inorganic particle layer includes a plurality of inorganic particles having an anisotropic shape including first inorganic particle length that is greater than a thickness of the inorganic particle layer, 
 wherein the substrate has a concave-convex member formed thereon, which has a pitch of 0.5 μm or less, a line width of 0.25 μm or less, a depth of 1 nm or more. 
   
     
     
       24. A polarizing plate comprising:
 a substrate;   a plurality of reflection layers disposed at a predetermined interval, wherein the reflection layers extend in a first direction and include a metal material;   a dielectric layer includes a dielectric layer material selected from the group consisting of SiO2, Al2O3, and MgF2; and   an inorganic particle layer includes a plurality of inorganic particles having an anisotropic shape including a first inorganic particle length in the first direction that is greater than a second inorganic particle length in a second direction along the first surface perpendicular to the first direction,   wherein the substrate has a concave-convex member formed thereon, which has a pitch of 0.5 μm or less, a line width of 0.25 μm or less, a depth of 1 nm or more.   
     
     
       25. A polarizing plate comprising:
 a substrate;   a plurality of reflection layers disposed at a predetermined interval, wherein the reflection layers extend in a first direction and include a metal material;   a dielectric layer includes a dielectric layer material selected from the group consisting of SiO2, Al2O3, and MgF2; and   an inorganic particle layer includes a plurality of inorganic particles having an anisotropic shape including a first inorganic particle length that is greater than a thickness of the inorganic particle layer,   wherein the substrate has a concave-convex member formed thereon, which has a pitch of 0.5 μm or less, a line width of 0.25 μm or less, a depth of 1 nm or more.   
     
     
       26. A polarizing plate comprising:
 a substrate;   an antireflection layer;   a first dielectric layer includes a dielectric layer material selected from the group consisting of SiO2, Al2O3, and MgF2;   a plurality of reflection layers disposed at a predetermined interval, wherein the reflection layers extend in a first direction and include a metal material;   a second dielectric layer includes a dielectric layer material selected from the group consisting of SiO2, Al2O3, and MgF2; and   an inorganic particle layer includes a plurality of inorganic particles having an anisotropic shape including a first inorganic particle length that is greater than a thickness of the inorganic particle layer,   wherein the substrate has a concave-convex member formed thereon, which has a pitch of 0.5 μm or less, a line width of 0.25 μm or less, a depth of 1 nm or more, and   wherein at least one of the dielectric layers are provided between the reflection layer and the antireflection layer.