Polarizer, optical film using the same, and image display device using the same

1. A polarizer containing a dichroic material in a matrix, wherein an in-plane retardation at a measurement wavelength providing no absorption is in a range of 1120 to 1350 nm, and wherein a distance between a measurement position providing a maximum value of the in-plane retardation and a measurement position providing a minimum value of the in-plane retardation is more than 0 mm and not more than 10 mm or not less than 100 mm.

2. The polarizer according to claim 1 , wherein a differential retardation fluctuation (σ) at the measurement wavelength providing no absorption is in a range of −5 nm/mm to 5 nm/mm.

3. The polarizer according to claim 1 , wherein at the measurement wavelength providing no absorption, a difference between the maximum value and the minimum value (in-plane retardation variation) is less than 60 nm.

4. The polarizer according to claim 1 , wherein the measurement wavelength is in a range of 800 to 1500 nm.

5. The polarizer according to claim 4 , wherein the measurement wavelength is 1000 nm.

6. The polarizer according to claim 1 , wherein the matrix is a polymer film.

7. The polarizer according to claim 6 , wherein the polymer film is a polyvinyl alcohol film.

8. The polarizer according to claim 1 , which is chip-cut.

9. An optical film comprising the polarizer according to claim 1 .

10. The optical film according to claim 9 , which further comprises a transparent protective layer, and the transparent protective layer is arranged on at least one surface of the polarizer.

11. The optical film according to claim 9 , wherein a pressure-sensitive adhesive layer is arranged on at least one outermost surface layer.

12. The optical film according to claim 9 , which further comprises at least either a polarization converter or a retardation film.

13. The optical film according to claim 12 , wherein the polarization converter is either an anisotropic reflective polarizer or an anisotropic light-scattering polarizer.

14. A liquid crystal panel comprising at least the polarizer according to claim 1 , wherein the polarizer is arranged on at least one surface of a liquid crystal cell.

15. A liquid crystal display comprising the liquid crystal panel according to claim 14 .

16. The liquid crystal display according to claim 15 , which has a flat light source for emitting polarized light.

17. An image display device comprising at least the polarizer according to claim 1 .

18. The image display device according to claim 17 , which is an electroluminescent display.

19. An in-house production method for producing the image display device according to claim 17 , which comprises a process of chip-cutting at least a polarizer containing a dichroic material in a matrix, wherein an in-plane retardation at a measurement wavelength providing no absorption is in a range of 950 to 1350 nm, and immediately bonding to the display device.

20. A liquid crystal panel comprising at least the optical film according to claim 9 , wherein the optical film is arranged on at least one surface of a liquid crystal cell.

21. A liquid crystal display comprising the liquid crystal panel according to claim 20 .

22. The liquid crystal display according to claim 21 , which has a flat light source for emitting polarized light.

23. An image display device comprising at least the optical film according to claim 9 .

24. The image display device according to claim 23 , which is an electroluminescent display.

25. An in-house production method for producing the image display device according to claim 17 , which comprises a process of chip-cutting at least an optical film comprising a polarizer, the polarizer containing a dichroic material in a matrix, wherein an in-plane retardation at a measurement wavelength providing no absorption is in a range of 950 to 1350 nm, and immediately bonding to the display device.