Method of evaluating image blur of optical film and optical film with reduced image blur

• US 9,590,210 B2
• Filed: 10/14/2014
• Issued: 03/07/2017
• Est. Priority Date: 10/15/2013
• Status: Active Grant

• Current Assignee: Cheil Industries Incorporated, Samsung Electronics Co. Ltd.
• Original Assignee: Cheil Industries Incorporated, Corning Precision Materials Company Limited (Corning Incorporated), Samsung Electronics Co. Ltd.
• Inventors: Kim, Hyunmin, Shin, Youmin, Shim, Hongshik, Oh, Young, Jeong, Chulho, Cho, Eunyoung
• Primary Examiner(s): Chowdhury, Tarifur
• Assistant Examiner(s): NIXON, OMAR H
• Application Number:
  US14/513,393
• Publication Number:
  US 20150103338A1
• Time in Patent Office: 875 Days
• Field of Search: 356/237.1
• US Class Current: 1/1
• CPC Class Codes: G01J 1/4209 Photoelectric exposure meters for determining the exposure time in recording or reproducing
• CPC Class Codes: G02B 27/34 illuminated
• CPC Class Codes: G02B 5/021 the diffusion taking place at the element's surface, e.g. by means of surface roughening or microprismatic structures
• CPC Class Codes: G02B 5/0236 the diffusion taking place within the volume of the element
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/0294 adapted to provide an additional optical effect, e.g. anti-reflection or filter
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses

Abstract

A method of evaluating an image blur of an optical film includes displaying a test pattern by driving an organic light-emitting display apparatus including the optical film, obtaining an image by capturing the test pattern using a digital camera, obtaining a spatial luminance distribution from the image, transforming the spatial luminance distribution into a sensation curve, and estimating a blur width from the sensation curve, where the blur width is a distance between peaks having negative minimum values, from among a plurality of peaks of the sensation curve.

Claims

1. An optical film comprising:

a high refractive index pattern layer including a first surface and a second surface facing each other, wherein the first surface comprises a pattern including a plurality of grooves and the high refractive index pattern layer is formed of a material having a refractive index greater than 1; and

a low refractive index pattern layer comprising a material having a refractive index less than the refractive index of the high refractive index pattern layer, wherein the low refractive index pattern layer comprises protrusions in matching shape to the plurality of grooves,

wherein the optical film satisfies the following condition;

2. The optical film of claim 1, wherein

each of the plurality of grooves has a stripe shape which extends in a predetermined direction, and

the plurality of grooves is 1-dimensionally arranged.

3. The optical film of claim 2, wherein the material of the high refractive index pattern layer or the material of the low refractive index pattern layer comprises a transparent resin material and a light diffuser.

4. The optical film of claim 1, wherein a lens pattern area, in which the plurality of grooves is defined, and a non-pattern area are alternately disposed in the optical film.

5. The optical film of claim 4, wherein a width of the lens pattern area is greater than a width of the non-pattern area.

6. The optical film of claim 1, wherein

each of the plurality of grooves has a dot shape, and

the plurality of grooves is 2-dimensionally arranged.

7. The optical film of claim 6, wherein each of the plurality of grooves has an oval shape.

8. The optical film of claim 6, wherein the plurality of grooves are arranged without intervals in a first direction and are spaced apart from each other at predetermined intervals in a second direction, which is perpendicular to the first direction.

9. The optical film of claim 1, wherein the protrusions comprise a plurality of layers having different refractive indexes from each other.

10. The optical film of claim 1, further comprising:

an anti-reflection layer disposed on the second surface of the high refractive index pattern layer, which is opposite to the first surface; and

a circular polarization film or a transmittance adjusting layer disposed between the high refractive index pattern layer and the anti-reflection layer.

11. An organic light-emitting display apparatus comprising:

an organic light-emitting display panel comprising a plurality of pixels comprising a plurality of organic emission layers, which emits light of different wavelengths, wherein each of the plurality of pixels has a micro cavity structure configured to resonates light corresponding to one of the different wavelengths; and

the optical film of claim 1 disposed on the organic light-emitting display panel.

12. The optical film of claim 1, wherein the blur width of a display panel is evaluated by a method comprising:

displaying a test pattern by driving an organic light-emitting display apparatus comprising the optical film;

obtaining an image by capturing the test pattern using a digital camera;

obtaining a spatial luminance distribution from the image;

transforming the spatial luminance distribution into a sensation curve; and

estimating a blur width from the sensation curve,

wherein the blur width is a distance between peaks having minimum negative values, from among a plurality of peaks of the sensation curve.

13. The optical film of claim 12, wherein

an x-axis of the sensation curve represents distance and a y-axis of the sensation curve represents sensation,

the plurality of peaks of the sensation curve comprises a plurality of peaks in x-y coordinates,

the blur width is a distance between two peaks having minimum negative y-coordinate values, from among peaks of the sensation curve in a region where the x-coordinates are negative and a region where the x-coordinates are positive.

14. The optical film of claim 12, wherein the test pattern is displayed on the optical film by a plurality of pixels disposed along a scanning line of a panel of the organic light-emitting display apparatus.

15. The optical film of claim 12, wherein the digital camera comprises a charge coupled device of the digital camera having a predetermined resolution which allows 30 or more charge coupled device pixels to cover one pixel of the organic light-emitting display apparatus.

16. The optical film of claim 12, wherein the spatial luminance distribution is estimated using a spectro-radiometer, and the spatial luminance distribution is transformed into the sensation curve using a Fourier transform and a numerical computation program.

17. The optical film of claim 16, wherein

the spatial luminance distribution is transformed into a spatial frequency function using the Fourier transform, and is transformed into the sensation curve by multiplying a color sensitivity function by the spatial frequency function and using an inverse Fourier transform.

18. The optical film of claim 1, further comprising;

a base layer;

a high refractive optical diffusion layer disposed on the base layer.

19. A display apparatus including the optical film of claim 1.