POLARIZING PLATE AND POLARIZING PLATE MANUFACTURING METHOD

• US 20200132903A1
• Filed: 10/15/2019
• Published: 04/30/2020
• Est. Priority Date: 10/26/2018
• Status: Active Grant

• Current Assignee: Dexerials Corporation
• Original Assignee: Dexerials Corporation
• Inventors: SHIBUYA, Kazuyuki, SAKABARA, Shigeshi, SUGAWARA, Toshiaki, MATSUNO, Yusuke, TAKADA, Akio
• Granted Patent: US 11,385,389 B2
• Time in Patent Office: Days
• CPC Class Codes: G02B 1/14 Protective coatings, e.g. hard coatings
• CPC Class Codes: G02B 1/18 Coatings for keeping optical surfaces clean, e.g. hydrophobic or photo-catalytic films G02B1/16 takes precedence
• CPC Class Codes: G02B 5/3008 comprising dielectric particles, e.g. birefringent crystals embedded in a matrix
• CPC Class Codes: G02B 5/3041 comprising multiple thin layers, e.g. multilayer stacks
• CPC Class Codes: G02B 5/3058 comprising electrically conductive elements, e.g. wire grids, conductive particles
• CPC Class Codes: G02F 1/133548 Wire-grid polarisers

Abstract

Provided are a polarizing plate having excellent optical properties and durability, and a method for manufacturing the polarizing plate. The polarizing plate includes: a transparent substrate transparent to light in a used wavelength band; lattice-shaped protrusions arranged on the transparent substrate at a pitch shorter than the wavelength of light in the used wavelength band, extending in a predetermined direction, and having a reflective layer, a first dielectric layer, an absorbing layer, and a second dielectric layer in this order; a dielectric portion consisting of a dielectric discontinuously formed on a surface of the lattice-shaped protrusions and a surface of a bottom floor between the lattice-shaped protrusions; and a water-repellent portion formed on a surface of the dielectric portion and having water-repellent properties.

Claims

1. A polarizing plate comprising:

a transparent substrate that is transparent to light in a used wavelength band;

lattice-shaped protrusions arranged on the transparent substrate at a pitch shorter than the wavelength of the light in the used band, extending in a predetermined direction, and having a reflective layer and a reflection-suppressing layer;

a dielectric portion made of a dielectric material formed discontinuously on a surface of the lattice-shaped protrusions and a surface of a bottom floor between the lattice-shaped protrusions; and

a water-repellent portion formed on a surface of the dielectric portion and having water-repellent properties.

2. The polarizing plate according to claim 1, wherein the dielectric portion is formed in an island shape or a dot shape on the surface of the lattice-shaped protrusions and the surface of the bottom floor between the lattice-shaped protrusions.

3. The polarizing plate according to claim 1, wherein the dielectric portion has a thickness of 0.8 to 1.2 nm.

4. The polarizing plate according to claim 1, wherein the dielectric portion is made of SiO₂, and

wherein the water-repellent portion is made of a silane compound having a fluoroalkyl group or an alkyl group.

5. The polarizing plate according to claim 1, wherein the dielectric portion is made of Al₂O₃, and

wherein the water-repellent portion is made of a phosphoric acid compound having a fluoroalkyl group or an alkyl group.

8. The polarizing plate according to claim 2, wherein the dielectric portion has a thickness of 0.8 to 1.2 nm.

9. The polarizing plate according to claim 2, wherein the dielectric portion is made of SiO2, and

wherein the water-repellent portion is made of a silane compound having a fluoroalkyl group or an alkyl group.

10. The polarizing plate according to claim 3, wherein the dielectric portion is made of SiO2, and

wherein the water-repellent portion is made of a silane compound having a fluoroalkyl group or an alkyl group.

11. The polarizing plate according to claim 2, wherein the dielectric portion is made of Al2O3, and

wherein the water-repellent portion is made of a phosphoric acid compound having a fluoroalkyl group or an alkyl group.

12. The polarizing plate according to claim 3, wherein the dielectric portion is made of Al2O3, and

wherein the water-repellent portion is made of a phosphoric acid compound having a fluoroalkyl group or an alkyl group.

6. A manufacturing method of a polarizing plate comprising:

film-forming a dielectric material on an optical member comprising a transparent substrate that is transparent to light in a used wavelength band and a lattice-shaped protrusions arranged on the transparent substrate at a pitch shorter than the wavelength of the light in the used band, extending in a predetermined direction, and having a reflective layer and a reflection-suppressing layer;

forming a dielectric portion made of the dielectric material discontinuously on a surface of the lattice-shaped protrusions and a surface of a bottom floor between the lattice-shaped protrusions; and

forming a water-repellent portion having water-repellent properties on a surface of the dielectric portion.

7. The manufacturing method according to claim 6, wherein the dielectric material is formed on the optical member by an ALD method.