Polarizing plate and polarizing plate manufacturing method
A polarizing plate capable of achieving high reliability and a method for manufacturing a polarizing plate. The polarizing plate includes a transparent substrate that is transparent to light of a used wavelength band; a metal grid in which a reflective layer made of a metal is arranged to extend in a predetermined direction on the transparent substrate at a pitch finer than a wavelength of light of the used band; a metal subgrid made of the same metal as the reflective layer formed on the metal grid at a pitch finer than that of the metal grid; and an absorbing layer made by filling a light absorbing material into a recess of the metal subgrid.
1. A polarizing plate comprising:
a transparent substrate that is transparent to light of a used wavelength band;
a metal grid in which a reflective layer made of a metal is arranged to extend in a predetermined direction on the transparent substrate at a pitch finer than a wavelength of light of the used band;
a metal subgrid made of the metal formed on the metal grid at a pitch finer than that of the metal grid; and
an absorbing section including a light absorbing material formed on the metal subgrid.
2. The polarizing plate according to claim 1 , wherein the absorbing section is formed by filling a light absorbing material in a recess of the metal subgrid.
3. The polarizing plate according to claim 2 , wherein the absorbing section is formed by film-forming a light absorbing material on an upper portion of the metal subgrid.
4. The polarizing plate according to claim 2 , wherein the metal subgrid has a pitch that is less than one half of a width of the reflective layer.
5. The polarizing plate according to claim 2 , wherein the metal subgrid has a recess having a depth that is one half or less than a height of a projection of the metal grid.
6. The polarizing plate according to claim 1 , wherein the absorbing section is formed by film-forming a light absorbing material on an upper portion of the metal subgrid.
7. The polarizing plate according to claim 6 , wherein the metal subgrid has a pitch that is less than one half of a width of the reflective layer.
8. The polarizing plate according to claim 6 , wherein the metal subgrid has a recess having a depth that is one half or less than a height of a projection of the metal grid.
9. The polarizing plate according to claim 1 , wherein the absorbing section is formed by oblique angle deposition of a light absorbing material on an upper portion of the metal subgrid.
10. The polarizing plate according to claim 9 , wherein the metal subgrid has a pitch that is less than one half of a width of the reflective layer.
11. The polarizing plate according to claim 9 , wherein the metal subgrid has a recess having a depth that is one half or less than a height of a projection of the metal grid.
12. The polarizing plate according to claim 1 , wherein the metal subgrid has a pitch that is less than one half of a width of the reflective layer.
13. The polarizing plate according to claim 1 , wherein the metal subgrid has a recess having a depth that is one half or less than a height of a projection of the metal grid.
14. A method for manufacturing a polarizing plate comprising:
forming a subgrid pattern on a surface of a metal layer film-formed on a transparent substrate that is transparent to light in a used wavelength band;
forming an absorbing layer by filling a light absorbing material in a recess of the subgrid pattern;
and forming a grid pattern arranged to be at a pitch finer than a wavelength of light in the used band by etching a metal layer,
to manufacture a polarizing plate having the transparent substrate, a metal grid extending in a predetermined direction in which a reflective layer made of a metal is arranged on the transparent substrate at a pitch finer than the wavelength of light of the used band, a metal subgrid made of the metal formed on the metal grid at a pitch finer than that of the metal grid, and an absorbing section formed by filling the light absorbing material in a recess of the metal subgrid.
15. A method for manufacturing a polarizing plate comprising:
forming a subgrid pattern on a surface of a metal film layer film-formed on a transparent substrate that is transparent to light in a used wavelength band;
forming a grid pattern arranged at a pitch finer than a wavelength of light in the used band by etching a metal layer; and
vapor depositing a light absorbing material on an upper portion of the subgrid pattern,
to manufacture a polarizing plate having the transparent substrate, a metal grid extending in a predetermined direction in which a reflective layer made of a metal is arranged on the transparent substrate at a pitch finer than the wavelength of light of the used band, a metal subgrid made of the metal formed on the metal grid at a pitch finer than that of the metal grid, and an absorbing section formed by vapor depositing the light absorbing material on an upper portion of the metal subgrid.