Polymer dispersed liquid crystal film comprising an optical lens having a first lens area and a second lens area and flat panel display device having the same

• US 10,446,797 B2
• Filed: 04/12/2016
• Issued: 10/15/2019
• Est. Priority Date: 06/09/2015
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Cho, Chio, Kwon, Jaejoong, Do, Yunseon, Yang, Byungchoon, Lee, Hyesog
• Primary Examiner(s): Lee, Paul C
• Application Number:
  US15/097,191
• Publication Number:
  US 20160363700A1
• Time in Patent Office: 1,281 Days
• CPC Class Codes: G02B 3/0087 with index gradient
• CPC Class Codes: G02B 30/27 involving lenticular arrays
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/292 by controlled diffraction or phased-array beam steering controlled diffraction for optical switching G02F1/31
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses

Abstract

There is provided a polymer dispersed liquid crystal film including a resin base, an optical lens on the resin base and including polymer dispersed liquid crystal particles within the resin base, and having a first lens area having a higher refractive index at an edge of the first lens area than at a center of the first lens area, and a second lens area surrounding the first lens area and having a lower refractive index at an outer edge of the second lens area than at an inner edge of the second lens area.

Claims

1. A polymer dispersed liquid crystal film comprising:

an optical lens comprising a resin base and polymer dispersed liquid crystal particles within the resin base, and having;

a first lens area having a higher refractive index at an outer edge of the first lens area than at a center of the first lens area, and having a lowest refractive index at the center of the first lens area; and

a second lens area surrounding the first lens area and having a lower refractive index at an outer edge of the second lens area than at an inner edge of the second lens area adjacent to the outer edge of the first lens area,

wherein the refractive index of the second lens area gradually decreases from the inner edge of the second lens area toward the outer edge of the second lens in all direction.

2. The polymer dispersed liquid crystal film of claim 1, wherein density of the polymer dispersed liquid crystal particles in the optical lens increases from the center of the first lens area toward the outer edge of the first lens area.

3. The polymer dispersed liquid crystal film of claim 1, wherein density of the polymer dispersed liquid crystal particles in the optical lens decreases from the inner edge of the second lens area toward the outer edge of the second lens area.

4. The polymer dispersed liquid crystal film of claim 1, wherein polymer dispersed liquid crystal particles in a base area between the optical lens and an other optical lens have a substantially uniform density.

5. The polymer dispersed liquid crystal film of claim 4, wherein the base area has a refractive index between a minimum refractive index of the first lens area of the optical lens and a maximum refractive index thereof.

6. The polymer dispersed liquid crystal film of claim 4, wherein the density of the polymer dispersed liquid crystal particles in the base area has a value between a minimum density of the optical lens and a maximum density thereof.

7. The polymer dispersed liquid crystal film of claim 4, wherein a thickness of the optical lens is about 100 μ

m or less.

8. The polymer dispersed liquid crystal film of claim 1, wherein the resin base is photocurable.

9. The polymer dispersed liquid crystal film of claim 8, wherein the resin base comprises at least one of polyester, epoxy, urethane, polyether, and polyacryl.

10. The polymer dispersed liquid crystal film of claim 9, wherein a dispersibility of the polymer dispersed liquid crystal particles is in a range of about 20 wt % to about 40 wt %.

11. A flat panel display device comprising:

a polymer dispersed liquid crystal film comprising an optical lens, the optical lens comprising a resin base and polymer dispersed liquid crystal particles dispersed within the resin base; and

a display panel attached to the polymer dispersed liquid crystal film,

wherein the optical lens has;

a first lens area having a higher refractive index at an outer edge of the first lens area than at a center of the first lens area, and having a lowest refractive index at the center of the first lens area; and

a second lens area surrounding the first lens area, and having a lower refractive index at an outer edge of the second lens area than at an inner edge of the second lens area adjacent to the outer edge of the first lens area, and

wherein the refractive index of the second lens area gradually decreases from the inner edge of the second lens area toward the outer edge of the second lens in all direction.

12. The flat panel display device of claim 11, wherein a base area between the optical lens and an other optical lens has a uniform refractive index.

13. The flat panel display device of claim 12, wherein optical lenses comprising the optical lens and the other optical lens are arranged in an array form within the polymer dispersed liquid crystal film.

14. The flat panel display device of claim 12, wherein the resin base comprises a photocurable resin.

15. The flat panel display device of claim 14, wherein the resin base is cured through at least two light exposures.

16. The flat panel display device of claim 15, wherein the resin base is partially cured using a mask one or more times.

17. The flat panel display device of claim 11, wherein the polymer dispersed liquid crystal film comprises a planar film.

18. The flat panel display device of claim 17, wherein the polymer dispersed liquid crystal film is attached over an entire image display surface of the display panel.

19. The flat panel display device of claim 18, wherein the display panel comprises a liquid crystal display (“

LCD”

) panel or an organic light emitting diode (“

OLED”

) display panel.