Device for testing optical properties and method for testing optical properties

Patent metadata

Field	Value
Publication number	US-10823892-B2
Application number	US-201716329976-A
Country	US
Kind code	B2
Filing date	Aug 29, 2017
Priority date	Sep 2, 2016
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

The present application relates to a device for testing optical properties and a method for testing optical properties using the same. The device of the present application has inexpensive manufacturing and maintenance costs, is capable of testing a wide range of plane directional phase differences, and provides the method for testing optical properties with improved identification efficiency of the phase retardation axis.

First claim

The invention claimed is:

1. A device for testing optical properties of a quarter-wave film comprising a light source that emits non-polarized light, a lower polarizer, a first quarter-wave film, a second quarter-wave film, an upper polarizer and a color detecting part in sequence;
wherein, the optical property to be tested is a phase retardation axis of the second quarter-wave film, the method comprises:
a step of fixing a phase retardation axis of said first quarter-wave film and an absorption axis of the lower polarizer so as to form an angle of 45 degree or 135 degree, wherein said second quarter-wave film has a plane directional phase difference known as the same value as that of said first quarter-wave film; and
a step of rotating said second quarter-wave film horizontally and determining that when the color of the light excluding wavelength of light corresponding to four times the plane directional phase difference of said second quarter-wave film is detected in said color detecting part, the phase retardation axis of said second quarter-wave film is parallel to the phase retardation axis of said first quarter-wave film.

2. The device according to claim 1 , wherein said light source emits said un-polarized light to said lower polarizer side.

3. The device according to claim 1 , wherein said lower polarizer and upper polarizer are disposed so that their absorption axes are parallel to each other.

4. The device according to claim 1 , wherein said first quarter-wave film or second quarter-wave film has a plane directional phase difference of 90 nm to 200 nm.

5. The device according to claim 1 , wherein said first quarter-wave film or second quarter-wave film has the same plane directional phase difference to each other.

6. The device according to claim 1 , wherein color of a light transmitting said upper polarizer is detected by said color detecting part to test the optical property of the quarter-wave film.

7. The device according to claim 6 , wherein the device evaluates the optical property when the color of the light excluding wavelength of light corresponding to four times a plane directional phase difference of said first quarter-wave film or second quarter-wave film is detected by said color detecting part.

8. The device according to claim 1 , wherein the optical property to be tested through said device is a phase retardation axis of the second quarter-wave film having a plane directional phase difference of a known value.

9. The device according to claim 8 , wherein the phase retardation axis of said second quarter-wave film is tested by horizontally rotating said second quarter-wave film in a state fixed such that an absorption axis of the lower polarizer and a phase retardation axis of the first quarter-wave film form an angle of 45° or 135°.

10. The device according to claim 9 , wherein when color of a light excluding wavelength of light corresponding to four times the plane directional phase difference of said second quarter-wave film is detected in said color detecting part, it is determined that the phase retardation axis of said second quarter-wave film is parallel to the phase retardation axis of the first quarter-wave film.

11. The device according to claim 1 , wherein a plane directional phase difference and a phase retardation axis of said first quarter-wave film have known values.

12. The device according to claim 1 , wherein the optical property to be tested through said device is plane directional phase differences of the first quarter-wave film and the second quarter-wave film each having a phase retardation axis of a known value.

13. The device according to claim 12 , wherein said plane directional phase difference is tested in a state disposed such that the phase retardation axes of said first quarter-wave film and said second quarter-wave film are fixed parallel to each other and said phase retardation axes form an angle of 45° or 135° with an absorption axis of the lower polarizer or the upper polarizer.

14. The device according to claim 13 , wherein a wavelength value corresponding to ¼ times the wavelength of light excluded from the wavelength of light detected in said color detecting part is determined as plane directional phase differences of the first quarter-wave film and the second quarter-wave film.

15. A method for testing optical properties comprising: a step of sequentially
forming a light source that emits un-polarized light, a lower polarizer, a first quarter-wave film, a second quarter-wave film, an upper polarizer and a color detecting part, and emitting un-polarized light from said light source to said lower polarizer side to transmit said upper polarizer; and a step of detecting color of light transmitting said upper polarizer in the color detecting part and testing the optical properties of the quarter-wave film;
wherein, the optical property to be tested is a phase retardation axis of the second quarter-wave film, the method comprises:
a step of fixing a phase retardation axis of said first quarter-wave film and an absorption axis of the lower polarizer so as to form an angle of 45 degree or 135 degree, wherein said second quarter-wave film has a plane directional phase difference known as the same value as that of said first quarter-wave film; and
a step of rotating said second quarter-wave film horizontally and determining that when the color of the light excluding wavelength of light corresponding to four times the plane directional phase difference of said second quarter-wave film is detected in said color detecting part, the phase retardation axis of said second quarter-wave film is parallel to the phase retardation axis of said first quarter-wave film.

16. The method for testing according to claim 15 , wherein the optical property to be tested is plane directional phase differences of the first quarter-wave film and the second quarter-wave film, the method comprises:
a step of fixing phase retardation axes of said first quarter-wave film and said second quarter-wave film to be parallel to each other, wherein said first quarter-wave film and said second quarter-wave film each has a phase retardation axis of a known value, and disposing said phase retardation axes so as to form an angle of 45° or 135° with an absorption axis of the lower polarizer or the upper polarizer; and
a step of determining a wavelength value corresponding to ¼ times wavelength of light excluded from a light detected in said color detecting part as plane directional phase differences of the first quarter-wave film and the second quarter-wave film.

Assignees

• Lg Chemical Ltd

Inventors

• Jo Min Yeong
• Park Jin Yong
• Park Dong Min
• Lee Won Chul
• Jung ki jun

Classifications

• G02B5/3083 Primary

  Birefringent or phase retarding elements (G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001) · CPC title

• G01J2009/002

  Wavefront phase distribution · CPC title

• G01J9/00 Primary

  Measuring optical phase difference (devices or arrangements for controlling the phase of light beams G02F1/01); Determining degree of coherence; Measuring optical wavelength (spectrometry G01J3/00) · CPC title

• G01M11/02 Primary

  Testing optical properties · CPC title

• G01M11/00

  Testing of optical apparatus; Testing structures by optical methods not otherwise provided for · CPC title