Optical film sample for testing A-type compensation film and testing method thereof

Abstract

The invention discloses an optical film sample for testing A-type compensation films, which comprises a plurality of layers of laminated to-be-tested A-type compensation films, and the to-be-tested A-type compensation films are phase compensation films of which the optical axes are parallel to the surfaces of films; and a high-transmittance transparent adhesive layer which does not influence the light polarization state condition is respectively adhered between the polarizing film for polarizing and between any two adjacent to-be-measured A-type compensation films. Through the combination of the compensation film and the polarization analyzer, the compensation value is digitized from the polarization degree, and the compensation value of the compensation film is accurately judged under the condition that no expensive professional equipment such as AXO SCAN is used for testing.

Description

Technical Field

[0001] The invention relates to an optical film sample and a testing method thereof. Background Art

[0002] With the continuous enrichment of display application scenarios and the continuous advancement of display technology, type A optical compensation film (A film, A-plate) is frequently used in various display devices, such as XR (extended reality), OLED screens, LC semi-reflective and semi-transparent, and fully reflective screens.

[0003] Currently, there are two options for testing type A optical compensation films.

[0004] Existing Solution 1: Directly use professional equipment such as AXO SCAN to test the product compensation value. Solution 1 has the following advantages and disadvantages: Advantages: Accurate test results. Disadvantages: The test equipment is expensive and is not cost-effective if it is not used frequently.

[0005] Existing Solution 2: Use a color card, stick it to the linear deflection device at 45°, and judge the hue at a wide viewing angle. Solution 2 has the following advantages and disadvantages: Advantage: The material compensation value range can be quickly judged. Disadvantage: Low accuracy. For materials with compensation values ​​that differ by less than 60nm, and for materials with the same compensation value but different materials or different suppliers, the color at a wide viewing angle is almost the same and cannot be judged. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art in testing type A optical compensation films, and provide an optical film sample for testing type A compensation films and a testing method thereof, so as to determine the compensation value of type A compensation films, thereby distinguishing the type A compensation films.

[0007] In order to solve the above technical problems, the present invention proposes the following technical solutions: an optical film sample for testing type A compensation film, comprising a plurality of stacked layers of type A compensation film to be tested, wherein the type A compensation film to be tested is a phase compensation film with an optical axis parallel to the surface of the film, a layer of polarizer for polarization; and a layer of high-transmittance transparent adhesive layer that does not affect the polarization state of light is respectively bonded between any two adjacent layers of type A compensation film to be tested.

[0008] The above technical solution is further limited in that: a high-transmittance transparent adhesive layer is provided between the polarizer generating the polarized light for testing and the type A compensation film to be tested, which is bonded to the type A compensation film to be tested and does not affect the polarization state of the light.

[0009] The above technical solution is further limited in that: the number of the type A compensation films to be tested is two, three or more layers.

[0010] The above technical solution is further limited in that: the above high-transmittance transparent adhesive layer is made of any high-transmittance homogeneous adhesive material.

[0011] In order to solve the above technical problems, the present invention proposes the following technical solutions: a method for testing the type A compensation film using the optical film sample, comprising the following steps:

[0012] Step 1: Allow polarized light to pass through the above optical film sample and calculate the degree of polarization;

[0013] Step 2: According to the polarization degree result, the compensation value of the type A compensation film to be tested is determined, so as to distinguish the type A compensation film to be tested.

[0014] In order to solve the above technical problems, the present invention proposes the following technical solutions: an optical film sample for testing type A compensation film, comprising several layers of type A compensation film to be tested and several layers of known type A compensation film, all of which are phase compensation films with optical axes parallel to the surface of the film, and the above-mentioned layers of type A compensation film are stacked; a polarizer for polarization; and a high-transmittance transparent adhesive layer that does not affect the polarization state of light is bonded between any two adjacent layers of type A compensation film.

[0015] The technical solution is further limited in that: a high-transmittance transparent adhesive layer is provided between the polarizer and the A-type compensation film to be tested or the known A-type compensation film, which is bonded to the A-type compensation film and does not affect the polarization state of the light.

[0016] The above technical solution is further limited in that the total number of the type A compensation films to be tested or the known type A compensation films is two layers, three layers or more layers.

[0017] The above technical solution is further limited in that: the above high-transmittance transparent adhesive layer is made of any high-transmittance homogeneous adhesive material.

[0018] In order to solve the above technical problems, the present invention proposes the following technical solutions: a method for testing the type A compensation film using the optical film sample, comprising the following steps:

[0019] Step 1: Allow polarized light to pass through the above optical film sample and calculate the degree of polarization;

[0020] Step 2: According to the polarization degree result, the compensation value of each layer of the A-type compensation film is determined, so as to distinguish the various layers of the A-type compensation film.

[0021] Compared with the prior art, the present invention has the following beneficial effects: the present invention amplifies the difference between the compensation values ​​of adjacent compensation films by superimposing multiple layers of films and selecting different wavebands, and combines with a polarizer to test the polarization degree of the overall structure and use the polarization degree data to visualize the compensation value of the multiple layers of films, so as to distinguish similar A-type compensation film materials and determine whether the compensation value of the material is the required compensation value. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic structural diagram of the first embodiment of an optical film sample for testing type A compensation film of the present invention.

[0023] Figure 2 It is a schematic structural diagram of the first embodiment of an optical film sample for testing type A compensation film and a polarizer of the present invention.

[0024] Figure 3 It is a schematic structural diagram of a second embodiment of an optical film sample for testing type A compensation film of the present invention.

[0025] Figure 4 It is a schematic diagram of the testing process.

[0026] Figure 5 This is a comparison chart of similar compensation values ​​of different manufacturers in Test Example 2.

[0027] Figure 6 This is a comparison chart of similar compensation values ​​of the same manufacturer in Test Example 3. DETAILED DESCRIPTION

[0028] See also Figure 1-2 A first embodiment of an optical film sample 1 for testing a type A compensation film comprises a plurality of stacked layers of type A compensation films 11 to be tested, a layer of high-transmittance transparent adhesive layer 12 is respectively bonded between any two adjacent layers of type A compensation films 11 to be tested, and a layer of high-transmittance transparent adhesive layer 12 is also bonded between a polarizing plate (hereinafter referred to as polarizer 100) for polarization and the type A compensation film 11 to be tested.

[0029] like Figure 2 As shown, when the polarizer 100 is set at Figure 1 When the optical film sample 1 of the test type A compensation film is shown, from bottom to top, they are polarizer 100, high transmittance transparent adhesive layer 12, type A compensation film 11 to be tested, high transmittance transparent adhesive layer 12, type A compensation film 11 to be tested, high transmittance transparent adhesive layer 12, and type A compensation film 11 to be tested.

[0030] According to actual test requirements, the number of the A-type compensation films 11 to be tested can be two, three or more layers, and the number of the high-transmittance transparent adhesive layers 12 also changes accordingly.

[0031] The polarizer 100 is a material layer with any polarizing function (metal grating, iodine-based dye polarizer, etc.), which allows natural light to pass through and converts it into linearly polarized light. The direction of its absorption axis or transmission axis needs to be known in advance.

[0032] The A-type compensation film 11 to be tested is a phase compensation film whose optical axis is parallel to the film surface, also called A-plate.

[0033] The above-mentioned high-transmittance transparent adhesive layer 12 is made of any high-transmittance homogeneous adhesive material, which plays the role of bonding each layer of the A-type compensation film 11 to be tested without affecting the polarization state of the light.

[0034] When the above-mentioned type A compensation film 11 is stacked, its slow axis should be parallel to each other to increase its compensation value, and the angle between the slow axis and the absorption axis of the polarizer 100 is 45° (the requirements of parallelism of the slow axis and 45° of the absorption axis are to make the conversion process simpler, and the compensation value of the type A compensation film 11 to be tested can also be confirmed through testing and calculation by using different angles).

[0035] See also Figure 3 A second embodiment of an optical film sample 2 for testing type A compensation film includes several layers of type A compensation film 21 to be tested and several layers of known type A compensation film 22. The slow axis angle of the compensation film can be designed by calculation to design the appropriate relative angles of each layer for stacking. The most convenient way is to make the slow axis angles of each layer parallel and only add the angles. A layer of high-transmittance transparent adhesive layer 23 is laminated between any two adjacent layers of type A compensation film 21 to be tested and known type A compensation film 22, and a layer of high-transmittance transparent adhesive layer 23 is also laminated between the polarizer 100 and the type A compensation film 21 to be tested or the known type A compensation film 22.

[0036] The core idea of ​​using the optical film sample 1 or 2 of the present invention to test the type A compensation film 11 or 21 is:

[0037] 1. By superimposing film materials, the compensation value difference between materials with similar compensation values ​​can be amplified;

[0038] 2. Design the overall compensation value of the final multilayer film material by stacking film materials and adding known compensation film materials; so that the polarization degree near a certain wavelength can be better characterized (such as the polarization degree of the multilayer film material structure designed by C manufacturer 90 and C manufacturer 140 at 720nm below).

[0039] The present invention also provides a method for testing the type A compensation film, comprising the following steps:

[0040] Step 1: Allow the polarized light generated by the polarizer 100 to pass through the optical film sample 1 or 2 to test the polarization degree;

[0041] Step 2: According to the polarization degree result, the compensation value of the A-type compensation film is determined, thereby distinguishing the various layers of the A-type compensation film.

[0042] See also Figure 4 The specific test process is as follows: Figure 1 or Figure 3 The optical film sample 1 or 2 shown is placed in Figure 4 The sample holder 7 is placed on the fixture 9 and fixed with masking tape. The sample holder 7 is moved on the slide rail 5 to be close to the entrance 4 of the integrating sphere until the sample holder 7 can no longer move. Click the software to test. The device will first rotate the shaft 6 to find the maximum and minimum angles of light transmission. The light outlet 8 will emit light of each wavelength and record the ratio of the maximum and minimum angles of light flux, thereby calculating the degree of polarization. Finally, the material compensation value is determined based on the result of the degree of polarization.

[0043] Example 1

[0044] This embodiment 1 is used to test whether the compensation film to be tested is a material with R0=90nm at 550nm. Three films with R0=110nm at 550nm (type A compensation films), four films to be tested (type A compensation films) and a polarizer 100 can be combined to test the polarization degree in a spectrophotometer.

[0045] If the compensation film to be tested is a material with R0=90nm at 550nm, then its polarization value will be around 0% at around 550nm.

[0046]

[0047]

[0048] It can be seen from the above table that at around 550nm (-1.11198), the polarization degree is close to 0%.

[0049] Example 2

[0050] At a wavelength of 440nm, the R0 of the 270 material from manufacturer A is approximately 270nm, and the R0 of the 270 material from manufacturer B is approximately 300nm.

[0051] The slow axes of two sheets of 270 materials from manufacturer A are superimposed (ie, at a wavelength of 440 nm, the R0 of the composite film is about 540 nm), and the angle between the slow axis and the absorption axis of the polarizer 100 is 45°.

[0052] Two sheets of 270 material from manufacturer B are also composited in the same manner (ie, at a wavelength of 440 nm, the R0 of the composite film is about 600 nm).

[0053] Place two groups of samples in the optical tester for testing. Figure 5 , Figure 5 The horizontal axis represents the wavelength of each light, and the vertical axis represents the compensation value R0 of the corresponding wavelength. In the data measured by the optical tester, the polarization degree of the sample group of manufacturer A's material at 440nm will be closer to 0%, thereby distinguishing materials with similar compensation values ​​from two different manufacturers.

[0054] Example 3

[0055] At a wavelength of 720nm, the R0 of the 90 material from manufacturer C is approximately 90nm, and the R0 of the 140 material from manufacturer C is approximately 140nm.

[0056] If two sheets of 90 material from manufacturer C are superimposed with their slow axes in parallel (ie, at a wavelength of 720nm, the R0 of the composite film is about 180nm), and the angle between their slow axes and the absorption axis of the polarizer is 45°.

[0057] The 140 material of manufacturer B is also compounded in the same manner (ie, at a wavelength of 720 nm, the R0 of the composite film is about 280 nm).

[0058] Place two groups of samples in the optical tester for testing. Figure 6 , Figure 6 The horizontal axis represents the wavelength of each light, and the vertical axis represents the compensation value R0 of the corresponding wavelength. In the obtained data, the polarization degree of the sample group of 90 materials from manufacturer C at 720nm will be closer to 0%, thereby distinguishing materials with similar compensation values ​​from the same manufacturer.

[0059]

[0060]

[0061] The present invention has the following beneficial effects: the present invention combines the compensation film with the polarizer to digitize the compensation value from the polarization degree, and can more accurately judge the compensation value of the compensation film without expensive professional equipment such as AXO SCAN for testing.

Claims

1. An optical film sample for testing type A compensation film, characterized in that: It includes: A plurality of stacked A-type compensation films to be tested, wherein the A-type compensation film to be tested is a phase compensation film with an optical axis parallel to the film surface; A polarizing film for polarization; as well as A layer of high-transmittance transparent adhesive layer which does not affect the polarization state of light is respectively adhered between any two adjacent layers of the A-type compensation films to be tested.

2. The optical film sample for testing type A compensation film according to claim 1, characterized in that: A high-transmittance transparent adhesive layer is provided between the polarizer and the A-type compensation film to be tested, which is bonded to the A-type compensation film to be tested and does not affect the polarization state of the light.

3. The optical film sample for testing type A compensation film according to claim 1, characterized in that: The number of the type A compensation films to be tested is two, three or more layers.

4. The optical film sample for testing type A compensation film according to claim 1, characterized in that: The high-transmittance transparent adhesive layer is made of any high-transmittance homogeneous adhesive material.

5. A method for testing a type A compensation film using the optical film sample according to any one of claims 1 to 4, characterized in that: It includes the following steps: Step 1: Allow polarized light to pass through the above optical film sample and calculate the degree of polarization; Step 2: According to the polarization degree result, the compensation value of the type A compensation film to be tested is determined, so as to distinguish the type A compensation film to be tested.

6. An optical film sample for testing type A compensation film, characterized in that: It includes several layers of A-type compensation films to be tested and several layers of known A-type compensation films, all of which are phase compensation films with optical axes parallel to the film surface, and the above-mentioned layers of A-type compensation films are stacked; a polarizing film for polarization; and A layer of high-transmittance transparent adhesive layer which does not affect the polarization state of light is respectively adhered between any two adjacent layers of A-type compensation films.

7. The optical film sample for testing type A compensation film according to claim 6, characterized in that: A high-transmittance transparent adhesive layer is provided between the polarizer and the A-type compensation film to be tested or a known A-type compensation film, which is bonded to the A-type compensation film and does not affect the polarization state of light.

8. The optical film sample for testing type A compensation film according to claim 6, characterized in that: The total number of the tested A-type compensation films or the known A-type compensation films is two, three or more layers.

9. The optical film sample for testing type A compensation film according to claim 6, characterized in that: The high-transmittance transparent adhesive layer is made of any high-transmittance homogeneous adhesive material.

10. A method for testing a type A compensation film using the optical film sample according to any one of claims 6 to 9, characterized in that: It includes the following steps: Step 1: Allow polarized light to pass through the above optical film sample and calculate the degree of polarization; Step 2: According to the polarization degree result, the compensation value of each layer of the A-type compensation film is determined, so as to distinguish the various layers of the A-type compensation film.

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