Method of manufacturing mold substrate for diffraction lattice light guide plate, and method of manufacturing diffraction lattice light guide plate

Patent metadata

Field	Value
Publication number	US-11331869-B2
Application number	US-201816635457-A
Country	US
Kind code	B2
Filing date	Aug 16, 2018
Priority date	Aug 16, 2017
Publication date	May 17, 2022
Grant date	May 17, 2022

Abstract

The present invention relates to a method of manufacturing a mold substrate for a diffraction lattice light guide plate, and a method of manufacturing a diffraction lattice light guide plate.

First claim

The invention claimed is:

1. A method of manufacturing a mold substrate for a diffraction lattice light guide plate, the method comprising:
preparing a faraday cage with a mesh having a sheet resistance of 0.5 Ω/sq or more provided on an upper surface of the faraday cage;
providing a sample substrate on a bottom surface of the faraday cage and carrying out flat plasma etching of the sample substrate;
designating a high etching region inside the faraday cage by examining the sample substrate after etching;
preparing a support having an inclined surface and positioning a base of the inclined surface in the high etching region of the faraday cage to align the support;
providing a substrate for a mold on the inclined surface of the support; and
plasma etching the substrate to simultaneously form a first inclined pattern portion at one side of the substrate and a second inclined pattern portion at the other side of the substrate,
wherein an etch rate of the plasma etching decreases and then reversely increases from an upper region to a lower region of the substrate on the inclined surface of the support,
wherein the first inclined pattern portion includes a first inclined recess pattern having a depth gradient, and
wherein the second inclined pattern portion includes a second inclined recess pattern having a depth difference of 0 nm to 50 nm.

2. The method of claim 1 , wherein a depth of the second inclined recess pattern is 70% to 130% of a maximum depth of the first inclined recess pattern.

3. The method of claim 1 , wherein a difference between an etch speed at a highest point of the substrate on the inclined surface of the support and an etch speed at a lowest point of the substrate on the inclined surface of the support is 30% or less.

4. The method of claim 1 , wherein the mesh portion is a metal mesh having a fluorocarbon radical adsorbed thereon.

5. The method of claim 1 , wherein the high etching region is linearly represented on the sample substrate.

6. The method of claim 1 , further comprising:
providing a mask including an opening pattern portion on the substrate for the mold.

7. The method of claim 1 , wherein a difference between a minimum depth and a maximum depth of the first inclined recess pattern is 100 nm or more and 200 nm or less.

8. The method of claim 1 , wherein the first inclined pattern portion is formed in the region where the etch rate decreases or the region where the etch rate reversely increases.

9. The method of claim 1 , wherein an etch direction during patterning is perpendicular to a lower surface of the faraday cage.

10. The method of claim 1 , wherein an angle of inclination of the support is 35° or more and 45° or less.

11. The method of claim 1 , wherein the support includes two inclined surfaces, and the base of each of the two inclined surfaces is positioned in a high etching region of the faraday cage.

12. A method of manufacturing a diffraction lattice light guide plate, the method comprising:
preparing a mold substrate for a diffraction lattice light guide plate according to the method of claim 1 ;
applying a resin composition on the mold substrate for the diffraction lattice light guide plate;
forming a diffraction lattice pattern by hardening the resin composition;
providing a transparent substrate on a surface opposite to a surface provided with a diffraction lattice pattern; and
separating the mold substrate to form the diffraction lattice light guide plate.

Assignees

• Lg Chemical Ltd

Inventors

• Her Eun Kyu
• Kim Chung Wan
• Jang Song Ho
• Shin Bu Gon
• Park Jeong Ho
• Yoon Jung Hwan
• Choo So Young

Classifications

• G02B6/0065 Primary

  Manufacturing aspects; Material aspects · CPC title

• H01J37/321

  the radio frequency energy being inductively coupled to the plasma · CPC title

• B29L2011/0075

  Light guides, optical cables · CPC title

• G02B6/0036

  2-D arrangement of prisms, protrusions, indentations or roughened surfaces · CPC title

• B29C41/14

  Dipping a core {(B29C41/10 takes precedence)} · CPC title