METHOD OF MEASURING OPTICAL PARAMETERS OF POLARIZER AND MEASURING DEVICE

• US 20200132569A1
• Filed: 01/18/2018
• Published: 04/30/2020
• Est. Priority Date: 12/29/2017
• Status: Active Grant

• Current Assignee: Huizhou China Star Optoelectronics Technology Co., Ltd.
• Original Assignee: Huizhou China Star Optoelectronics Technology Co., Ltd.
• Inventors: HAI, Bo
• Granted Patent: US 10,746,628 B2
• Time in Patent Office: Days
• CPC Class Codes: G01M 11/0207 Details of measuring devices
• CPC Class Codes: G02B 5/3025 Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state G02B5/3008, G02B5/3016 take precedence
• CPC Class Codes: G02B 5/3033 in the form of a thin sheet or foil, e.g. Polaroid
• CPC Class Codes: G02B 5/3083 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 Class Codes: G02F 1/1335 Structural association of cells with optical devices, e.g. polarisers or reflectors

Abstract

The disclosure discloses a method of measuring optical parameters of a polarizer and a measuring device. The polarizer includes a compensation film and a PVA layer. The measuring method includes the following steps. In the first state, providing an incident linearly polarized light sequentially to pass through the compensation film and the PVA layer, acquiring a first measurement parameter and a second measurement parameter when the brightness of the light emitted from the polarizer is lowest and is highest. In the second state, providing the incident linearly polarized light sequentially to pass through the PVA layer and the compensation film, acquiring a third measurement parameter and a fourth measurement parameter when the brightness of the light emitted from the polarizer is lowest and is highest; and acquiring optical parameters of the compensation film and/or the PVA layer in the polarizer according to one or more of the above measurement parameters.

Claims

1. A method of measuring optical parameters of a polarizer, wherein the polarizer comprises a compensation film and a PVA layer, and the measuring method comprises:

in a first state, providing an incident linearly polarized light to pass through the compensation film and the PVA layer sequentially, acquiring a first measurement parameter and a second measurement parameter when a brightness of light emitted from the polarizer is lowest and is highest;

in a second state, providing the incident linearly polarized light to pass through the PVA layer and the compensation film sequentially, acquiring a third measurement parameter and a fourth measurement parameter when a brightness of light emitted from the polarizer is lowest and is highest; and

acquiring optical parameters of the compensation film and/or the PVA layer in the polarizer according to one or more of the first measurement parameter, the second measurement parameter, the third measurement parameter, and the fourth measurement parameter, the optical parameters comprise any one or more of a dark state brightness, a contrast, and a polarization degree.

2. The measuring method according to claim 1, wherein the first measurement parameter in the first state comprises a dark state brightness Lv₁, the second measurement parameter in the first state comprises a bright state brightness Lv₂;

the third measurement parameter in the second state comprises a dark state brightness Lv₃, and the fourth measurement parameter in the second state comprises a bright state brightness Lv₄.

3. The measuring method according to claim 2, wherein the optical parameters comprise any one or more of the following:

the effect of the PVA layer on the dark state brightness is;

Lv₃;

the effect of the PVA layer and the compensation film on the dark state brightness is;

Lv₁;

the effect of the compensation film on the dark state brightness is;

Lv₁−

Lv₃;

the effect of the PVA layer on the contrast is;

Lv₄/Lv₃;

the effect of the PVA layer and the compensation film on the contrast is;

Lv₂/Lv₁;

the effect of the compensation film on the contrast is;

(Lv₄/Lv₃)−

(Lv₂/Lv₁);

the effect of the PVA layer on the polarization degree is;

(Lv₄−

Lv₃)/(Lv₃+Lv₄);

the effect of the PVA layer and the compensation film on the polarization degree is;

(Lv₂−

Lv₁)/(Lv₁+Lv₂);

the effect of the compensation film on the polarization degree is;

(Lv₄−

Lv₃)/(Lv₃+Lv₄)−

(Lv₂−

Lv₁)/(Lv₁+Lv₂).

4. The measuring method according to claim 2, wherein the measuring method further comprises:

in the first state, acquiring a first transmission spectrum and a second transmission spectrum when a brightness of light emitted from the polarizer is lowest and is highest; and

in the second state, acquiring a third transmission spectrum and a fourth transmission spectrum when a brightness of light emitted from the polarizer is lowest and is highest.

5. The measuring method according to claim 1, wherein the first measurement parameter in the first state comprises a dark state transmittance T_1⊥

and the second measurement parameter in the first state comprises a bright state transmittance T_2//; and

the third measurement parameter in the second state comprises a dark state transmittance T_3⊥

, and the fourth measurement parameter in the second state comprises a bright state transmittance T_4//.

6. The measuring method according to claim 5, wherein the optical parameters comprise any one or more of the following:

the effect of the PVA layer on the dark state brightness is;

T_3⊥

;

the effect of the PVA layer and the compensation film on the dark state brightness is;

T_{1 ⊥}

;

the effect of the compensation film on the dark state brightness is;

T_1⊥

−

T_3⊥

;

the effect of the PVA layer on the polarization degree is;

(T_4//−

T_3⊥

)/(T_3⊥

+T_4//);

the effect of the PVA layer and the compensation film on the polarization degree is;

(T_2//−

T_1⊥

)/(T_1⊥

+T_2//);

the effect of the compensation film on the polarization degree is;

(T_4//−

T_3⊥

)/(T_3⊥

+T_4//)−

√

(T_2//−

T_1⊥

)/(T_1⊥

+T_2//).

7. The measuring method according to claim 1, wherein the polarizer further comprises one or more of a substrate layer, a protective layer, and an adhesive layer.

8. The measuring method according to claim 5, wherein the first measurement parameter in the first state comprises a dark state brightness Lv₁, the second measurement parameter in the first state comprises a bright state brightness Lv₂;

the third measurement parameter in the second state comprises a dark state brightness Lv₃, and the fourth measurement parameter in the second state comprises a bright state brightness Lv₄.

9. The measuring method according to claim 8, wherein the optical parameters comprise any one or more of the following:

the effect of the PVA layer on the dark state brightness is;

Lv₃;

the effect of the PVA layer and the compensation film on the dark state brightness is;

Lv₁;

the effect of the compensation film on the dark state brightness is;

Lv₁−

Lv₃;

the effect of the PVA layer on the contrast is;

Lv₄/Lv₃;

the effect of the PVA layer and the compensation film on the contrast is;

Lv₂/Lv₁;

the effect of the compensation film on the contrast is;

(Lv₄/Lv₃)−

(Lv₂/Lv₁);

the effect of the PVA layer on the polarization degree is;

(Lv₄−

Lv₃)/(Lv₃+Lv₄);

the effect of the PVA layer and the compensation film on the polarization degree is;

(Lv₂−

Lv₁)/(Lv₁+Lv₂);

the effect of the compensation film on the polarization degree is;

(Lv₄−

Lv₃)/(Lv₃+Lv₄)−

(Lv₂−

Lv₁)/(Lv₁+Lv₂).

10. The measuring method according to claim 8, wherein the measuring method further comprises:

in the first state, acquiring a first transmission spectrum and a second transmission spectrum when a brightness of light emitted from the polarizer is lowest and is highest; and

in the second state, acquiring a third transmission spectrum and a fourth transmission spectrum when a brightness of light emitted from the polarizer is lowest and is highest.

11. The measuring method according to claim 6, wherein the first measurement parameter in the first state comprises a dark state brightness Lv₁, the second measurement parameter in the first state comprises a bright state brightness Lv₂;

the third measurement parameter in the second state comprises a dark state brightness Lv₃, and the fourth measurement parameter in the second state comprises a bright state brightness Lv₄.

12. The measuring method according to claim 11, wherein the optical parameters comprise any one or more of the following:

the effect of the PVA layer on the dark state brightness is;

Lv₃;

the effect of the PVA layer and the compensation film on the dark state brightness is;

Lv₁;

the effect of the compensation film on the dark state brightness is;

Lv₁−

Lv₃;

the effect of the PVA layer on the contrast is;

Lv₄/Lv₃;

the effect of the PVA layer and the compensation film on the contrast is;

Lv₂/Lv₁;

the effect of the compensation film on the contrast is;

(Lv₄/Lv₃)−

(Lv₂/Lv₁);

the effect of the PVA layer on the polarization degree is;

(Lv₄−

Lv₃)/(Lv₃+Lv₄);

the effect of the PVA layer and the compensation film on the polarization degree is;

(Lv₂−

Lv₁)/(Lv₁+Lv₂);

the effect of the compensation film on the polarization degree is;

(Lv₄−

Lv₃)/(Lv₃+Lv₄)−

(Lv₂−

Lv₁)/(Lv₁+Lv₂).

13. The measuring method according to claim 11, wherein the measuring method further comprises:

in the first state, acquiring a first transmission spectrum and a second transmission spectrum when a brightness of light emitted from the polarizer is lowest and is highest; and

in the second state, acquiring a third transmission spectrum and a fourth transmission spectrum when a brightness of light emitted from the polarizer is lowest and is highest.

14. A measuring device for optical parameters of a polarizer, comprising a light source arranged along an optical path, a first stage, a rotatable stage, a second stage, and a brightness meter, wherein the first stage, the rotatable stage, and the second stage are provided with through holes so that the brightness meter can receive light emitted by the light source, the first stage and the second stage are respectively configured to carry a standard polarizer, and the rotatable stage is configured to bear a polarizer to be measured.

15. The measuring device according to claim 14, wherein the first stage, the rotatable stage and the second stage are respectively provided with a reference edge configured to limit the polarizer placed thereon.

16. The measuring device according to claim 14, wherein the brightness meter is a spectrophotometer.