Liquid crystal panel and manufacturing method of the same

• US 9,927,563 B2
• Filed: 10/08/2014
• Issued: 03/27/2018
• Est. Priority Date: 10/10/2013
• Status: Active Grant

• Current Assignee: Tianma Microelectronics Company Limited
• Original Assignee: NLT Technologies, Ltd. (Tianma Microelectronics Company Limited)
• Inventors: Miyake, Tomomi, Mizokuchi, Chikaaki
• Primary Examiner(s): Briggs, Nathanael R
• Assistant Examiner(s): PETERSON, WILLIAM D
• Application Number:
  US14/509,573
• Publication Number:
  US 20150103294A1
• Time in Patent Office: 1,266 Days
• Field of Search: 349158
• CPC Class Codes: G02B 5/208 for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation
• CPC Class Codes: G02B 5/22 Absorbing filters G02B5/201 - G02B5/208 take precedence
• CPC Class Codes: G02F 1/1309 Repairing; Testing

Abstract

Provided are a liquid crystal panel and a method of manufacturing method of manufacturing a liquid crystal panel. The liquid crystal panel includes a first transparent substrate; a second transparent substrate; and a liquid crystal layer formed between the first transparent substrate and the second transparent substrate. The first transparent substrate and the second transparent substrate have transparency in a visible light region and an ultraviolet absorptive property. At least one of the first transparent substrate and the second transparent substrate includes a structure arranged in a predetermined region thereof, where the structure transmits ultraviolet rays in a specific wavelength range.

Claims

1. A liquid crystal panel comprising:

a first transparent substrate;

a second transparent substrate; and

a liquid crystal layer formed between the first transparent substrate and the second transparent substrate,

wherein the first transparent substrate and the second transparent substrate have transparency in a visible light region and an ultraviolet absorptive property, and

at least one of the first transparent substrate and the second transparent substrate comprises a structure arranged in a predetermined region thereof, the structure transmitting ultraviolet rays in a specific wavelength range, and the predetermined region corresponding to a location where an orientation abnormality occurs in the liquid crystal layer.

2. The liquid crystal panel of claim 1,

wherein the specific wavelength range is a wavelength range in which energy of ultraviolet rays is higher than chemical bond energy of a molecular chain that is on a surface of a foreign matter existing in the predetermined region and that causes an orientation abnormality in the liquid crystal layer, and

the structure is formed such that an orientation of a portion of the liquid crystal layer corresponding to the predetermined region is controlled by being irradiated with the ultraviolet rays in the specific wavelength range.

3. The liquid crystal panel of claim 1,

wherein at least one of the first transparent substrate and the second transparent substrate comprises a hole as the structure, the hole being formed on a surface of the at least one of the first transparent substrate and the second transparent substrate at an opposite side to the liquid crystal layer.

4. The liquid crystal panel according to claim 3,

wherein a thickness of each of the first transparent substrate and the second transparent substrate and a depth of the hole are set such that ultraviolet rays in a wavelength range being less than or equal to 250 nm pass through the predetermined region and are absorbed in regions of the first transparent substrate and the second transparent substrate other than the predetermined region.

5. The liquid crystal panel of claim 4,

wherein the at least one of the first transparent substrate and the second transparent substrate is less than or equal to 0.2 mm in thickness in a portion where the hole exists.

6. The liquid crystal panel of claim 3,

wherein the hole is filled with an adhesive material for fixing a polarization plate onto the at least one of the first transparent substrate and the second transparent substrate, the polarization plate being arranged at at least one of a light-incident surface and light-outgoing surface of the liquid crystal panel.

7. The liquid crystal panel of claim 3,

wherein the hole is filled with a substance that

is transparent to light in a visible light region and

is different in a refractive index in the visible light region from the at least one of the first transparent substrate and the second transparent substrate.

8. The liquid crystal panel of claim 3,

wherein the hole is provided by excavating the at least one of the first transparent substrate and the second transparent substrate such that a side surface of the hole extends in a normal direction of a surface of the at least one of the first transparent substrate and the second transparent substrate.

9. The liquid crystal panel of claim 3,

wherein the hole is provided by excavating the at least one of the first transparent substrate and the second transparent substrate such that a side surface of the hole inclines at a predetermined angle with respect to a normal direction of a surface of the at least one of the first transparent substrate and the second transparent substrate and an inner diameter of the hole gradually reduces as a depth becomes deeper.

10. The liquid crystal panel of claim 1,

wherein the liquid crystal panel is a liquid crystal panel that works in an IPS mode.

11. A method of manufacturing a liquid crystal panel, comprising:

forming a liquid crystal layer between a first transparent substrate and a second transparent substrate, the first transparent substrate and the second transparent substrate having transparency in a visible light region and an ultraviolet absorptive property;

forming a structure that transmits ultraviolet rays in a specific wavelength range in a predetermined region on at least one of the first transparent substrate and the second transparent substrate, and the predetermined region corresponding to a location where an orientation abnormality occurs in the liquid crystal layer; and

irradiating a portion of the liquid crystal layer corresponding to the predetermined region with the ultraviolet rays in the specific wavelength range.

12. The method of claim 11,

wherein the specific wavelength range is a wavelength range in which energy of ultraviolet rays is higher than chemical bond energy of a molecular chain that is on a surface of a foreign matter existing in the predetermined region and that causes an orientation abnormality in the liquid crystal layer, and

the irradiating the portion of the liquid crystal layer comprises controlling orientation of the portion of the liquid crystal layer corresponding to the predetermined region by irradiating the portion with the ultraviolet rays in the specific wavelength range.

13. The method of claim 11,

wherein the forming the structure comprises forming a hole on a surface of the at least one of the first transparent substrate and the second transparent substrate at an opposite side to the liquid crystal layer.

14. The method of claim 13,

wherein the irradiating the portion of the liquid crystal layer comprises irradiating an entire surface of at least one of the first transparent substrate and the second transparent substrate or the predetermined region on the at least one of the first transparent substrate and the second transparent substrate, with the ultraviolet rays in the specific wavelength range.

15. The method of claim 14,

wherein the irradiating the portion of the liquid crystal layer comprises irradiating the portion of the liquid crystal layer with non-polarized ultraviolet rays.

16. The method of claim 14,

wherein the forming the liquid crystal layer comprises carrying out orientation treatment for orienting the liquid crystal layer, and

the irradiating the portion of the liquid crystal layer comprises irradiating the portion of the liquid crystal layer with linear-polarized ultraviolet rays polarized in a direction other than an orientation direction of the orientation treatment.

17. The method of claim 13 further comprising, after the irradiating the portion of the liquid crystal layer,

filling the hole with an adhesive material for fixing a polarization plate to the at least one of the first transparent substrate and the second transparent substrate, the polarization plate being arranged at at least one of a light-incident surface and light-outgoing surface of the liquid crystal panel.

18. The method of claim 13, further comprising, after the irradiating the portion of the liquid crystal layer,

filling the hole with a substance that

is transparent to light in a visible light region and

is different in a refractive index in the visible light region from the at least one of the first transparent substrate and the second transparent substrate.

19. The method of claim 11, further comprising, after the forming the liquid crystal layer and before the forming the structure,

confirming an existence of an orientation abnormality in the liquid crystal layer, a location where the orientation abnormality occurs, and a shape of the orientation abnormality.

20. The method of claim 13,

wherein the forming the structure comprises forming the hole by excavating the at least one of the first transparent substrate and the second transparent substrate to form a side surface of the hole extending in a normal direction of a surface of the at least one of the first transparent substrate and the second transparent substrate, and

the irradiating the portion of the liquid crystal layer comprises irradiating the portion of the liquid crystal layer with the ultraviolet rays in the specific wavelength range with adjusting an optical axis of the ultraviolet rays or an angle of the at least one of the first transparent substrate and the second transparent substrate so as to make a direction of the optical axis and a normal direction of a surface of the at least one of the first transparent substrate and the second transparent substrate the same.

21. The method of claim 13,

wherein the forming the structure comprises forming the hole by excavating the at least one of the first transparent substrate and the second transparent substrate to form a side surface of the hole inclining at a predetermined angle with respect to a normal direction of a surface of the at least one of the first transparent substrate and the second transparent substrate and to gradually reduce an inner diameter of the hole as a depth becomes deeper, and

the irradiating the portion of the liquid crystal layer comprises irradiating the portion of the liquid crystal layer with the ultraviolet rays in the specific wavelength range with adjusting an optical axis of the ultraviolet rays or an angle of the at least one of the first transparent substrate and the second transparent substrate so as to incline the optical axis at a predetermined angle with respect to the normal direction of a surface of the at least one of the first transparent substrate and the second transparent substrate.

22. The method of claim 21,

wherein the irradiating the portion of the liquid crystal layer comprises irradiating at least one of the first transparent substrate and the second transparent substrate with the ultraviolet rays in the specific wavelength range omnidirectionally by rotating the first transparent substrate and the second transparent substrate while maintaining a state where the optical axis of the ultraviolet rays in the specific wavelength range inclines at the predetermined angle with respect to the normal direction of a surface of the at least one of the first transparent substrate and the second transparent substrate.