Full-closed automatic measuring device for alignment angle of release film

Abstract

The utility model belongs to the technical field of optical measuring instruments, and relates to a release film alignment angle totally-closed automatic measuring device which comprises a main body part and a light shield, the light shield is used for covering the main body part, and the main body part comprises a light source, a first polaroid and a second polaroid which are sequentially arranged from bottom to top. The first polaroid and the second polaroid are horizontally arranged, the main body part further comprises an illuminometer, and a photosensitive probe of the illuminometer is located right above the second polaroid. According to the utility model, the testing accuracy and testing efficiency of the alignment angle are improved, the instrument cost is low, the testing method is simple, and the technical problem of alignment angle testing in the prior art is effectively solved.

Description

Technical Field

[0001] This utility model belongs to the field of optical measuring instrument technology, specifically relating to a fully enclosed automatic measuring device for the alignment angle of release film. Background Technology

[0002] Polarizing films, as specialized optical filters, play an indispensable role in many fields. A typical polarizing film consists of a six-layer structure, such as... Figure 1 As shown, the components are a protective film 20, a first TAC film 21 (cellulose triacetate film), a PVA film 22 (polyvinyl alcohol film), a second TAC film 23, a pressure-sensitive adhesive 24, and a release film 25. The protective film is made of PET or PE and its function is to protect the first TAC film. The PVA film serves as a polarizing layer. Because PVA film is prone to absorbing water and fading, losing its polarizing properties, the first and second TAC films are used to isolate moisture and air on both sides of the PVA film, preventing the PVA film from shrinking and deforming, thus supporting and protecting the PVA film and protecting the polarizing layer. Two TAC films sandwiching one PVA film constitute what is commonly referred to as the original polarizer. The pressure-sensitive adhesive is applied to the outside of the second TAC film and its function is to bond the original polarizer to the display panel of the liquid crystal display. The release film is coated with silicone on one side and its function is to protect the pressure-sensitive adhesive.

[0003] As can be seen, release film is used as the release layer for polarizers to prevent the pressure-sensitive adhesive from being contaminated or damaged before use. This release film protects the polarizer body until final lamination. During the production process, this type of film (PET polyester film) has a relatively large transverse width, with most production lines having a transverse stretching width between 8.5-11m. After the film undergoes longitudinal stretching, due to the different degrees of stretching at different locations (middle and edges), microscopically, the stretching causes molecules to exhibit directional movement. This ultimately results in an oriented state during the setting stage. The direction of this oriented state forms an angle with the transverse direction, becoming the molecular orientation angle, or alignment angle. Macroscopically, the alignment angle reflects the film's bowing phenomenon; the alignment angle is the angle of film bowing. Bowing phenomena are as follows... Figure 2 As shown, when the film enters the transverse stretching zone, the straight line in the preheating zone becomes a convex line, then becomes a straight line again in the later stage of the stretching process, and when the stretching is completed, the straight line becomes a concave line. The concavity is further intensified in the shaping zone. The curvature is expressed by the ratio of the curvature deformation to the film width: δ=b / w, where δ is the curvature (%), b is the curvature deformation, convex is (-), concave is (+), and w is the film width.

[0004] The alignment angle of the release film can affect the optical performance of the original polarizer, which in turn affects the performance of downstream products. In order not to affect the optical performance testing of the polarizer, the alignment angle of the release film should be close to zero. Therefore, it is necessary to test the alignment angle of the release film.

[0005] In existing technology, the orientation angle of a thin film is measured using the orthogonal principle of two polarizers. By placing a stretched and oriented thin film between the two polarizers, making the longitudinal direction of the thin film parallel to the orthogonal direction of the upper polarizer when it is in an orthogonal state, the polarization direction of natural light passing through the lower polarizer will be deflected at a certain angle due to the influence of the film's orientation when it passes through the thin film. When this polarized light reaches the upper polarizer, it will not be completely orthogonal. Some of the light rays with the same polarization direction as the upper polarizer pass through the upper polarizer, making it appear bright in the field of view. Then, the thin film is rotated clockwise by a certain angle, and the field of view returns to darkness as observed by the naked eye. The angle of rotation of the thin film is the orientation angle of the thin film.

[0006] For example, patent CN217637239U discloses a membrane material alignment angle measuring device, including a frame. The frame contains a second polarizer carrier plate for placing a polarizer, a membrane material carrier plate for placing a membrane material, and a first polarizer carrier plate for placing a polarizer. The second polarizer carrier plate, the membrane material carrier plate, and the first polarizer carrier plate are arranged parallel to each other and each has a third light-transmitting hole. The membrane material carrier plate is also provided with a rotating component and a scale display that cooperates with the rotating component. The rotating component can be driven to rotate the membrane material on the membrane material carrier plate.

[0007] However, the above-mentioned method for testing the alignment angle still has the following drawbacks: it relies on the tester's naked eye to observe the brightness of the two polarizers, requires repeated rotation of the polarizers for comparison of the light source carrier, is greatly affected by changes in the external light source carrier and human testing errors, cannot be automated, and results in poor test accuracy; the method for measuring the alignment angle is complex, and the measuring instruments are expensive, making it difficult to meet the needs of large-scale use.

[0008] Therefore, it is necessary to study a release film alignment angle measuring device with high automation, high testing accuracy, simple measurement method, and low instrument cost. Utility Model Content

[0009] The purpose of this invention is to solve the above-mentioned problems in the existing technology and to provide a fully enclosed automatic measuring device for the alignment angle of release film.

[0010] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0011] A fully enclosed automatic measurement device for the alignment angle of a release film includes a main body, which includes a light source, a first polarizer, and a second polarizer arranged sequentially from bottom to top. Both the first and second polarizers are horizontally arranged. The main body also includes an illuminance meter, with the photosensitive probe of the illuminance meter located directly above the second polarizer. The fully enclosed automatic measurement device for the alignment angle of a release film also includes a light shield, which is used to cover the main body.

[0012] As a preferred technical solution:

[0013] The fully enclosed automatic measurement device for the alignment angle of a release film, as described above, also includes a light source carrier plate, a first polarizer carrier plate, and a second polarizer carrier plate, all of which are arranged horizontally.

[0014] The light source is installed inside the light source carrier plate; a vertical first light-passing hole is provided at the center of the top of the light source carrier plate, and the first light-passing hole is located directly above the light source;

[0015] A vertical second light-transmitting hole is provided at the center of the first polarizer carrier plate, and the first polarizer covers the second light-transmitting hole;

[0016] The bottom center of the second polarizer carrier is provided with a vertical fourth light-passing hole, and the second polarizer covers the fourth light-passing hole.

[0017] The top surface of the light source carrier is connected to the bottom surface of the first polarizer carrier, and the second light-transmitting hole is located directly above the first light-transmitting hole.

[0018] As described above, in a fully enclosed automatic measurement device for the alignment angle of a release film, the photosensitive probe of the illuminometer is installed inside the second polarizer carrier plate and directly above the fourth light-transmitting hole.

[0019] As described above, in a fully enclosed automatic measurement device for the alignment angle of a release film, the display of the illuminometer is mounted on top of the second polarizer carrier plate.

[0020] The fully enclosed automatic measurement device for the alignment angle of release film as described above also includes a support cylinder, a scale, and a rotating platform in its main body.

[0021] Both the dial and the rotating platform are arranged horizontally.

[0022] The top surface of the first polarizer carrier plate is connected to the bottom surface of the support cylinder; the top surface of the support cylinder is connected to the bottom surface of the dial; the rotating platform is located at the center of the dial and is rotatably connected to the dial; the rotating platform is provided with an indicator scale line pointing to the dial; the center of the rotating platform is provided with a vertical third light-transmitting hole, which is located directly above the second light-transmitting hole and the first polarizer; the second polarizer carrier plate is located above the rotating platform.

[0023] As described above, in a fully enclosed automatic measurement device for the alignment angle of a release film, the rotating platform is rotatably connected to the dial via protrusions and grooves.

[0024] The fully enclosed automatic measurement device for the alignment angle of a release film, as described above, further includes a top plate and a support; the top plate is arranged horizontally; the second polarizer carrier is supported by the top plate, and the top plate is connected to the light source carrier through the support.

[0025] As described above, the fully enclosed automatic measurement device for the alignment angle of a release film has a light shield consisting of a cube surrounded by six stainless steel plates with attached polyimide films.

[0026] The principle of this utility model is as follows:

[0027] During the transverse stretching process of biaxially oriented films, factors such as the track, airflow, temperature, and stretching ratio cause inconsistent stretching orientations between the edges and the center, generally with a larger orientation in the center and smaller orientations on both sides. During transverse stretching, the overall direction of the film's movement is longitudinal, causing it to stretch obliquely upwards, ultimately forming an oriented state in the shaping zone. This oriented state forms an angle with the transverse direction, which is the alignment angle. The alignment angle creates a stable phase delay in the polarized light field, causing a certain change in the polarized light field. In this invention, the light emitted from the light source changes in intensity after passing through the first polarizer, the release film, and the second polarizer. While the light shield blocks external light source interference, the illuminance meter sensitively and accurately detects and displays the light intensity change information. The rotating platform and the release film are then rotated relative to the scale. The rotation angle of the rotating platform is determined by the change in light intensity displayed by the illuminance meter, allowing the calculation of the release film's alignment angle. This invention not only avoids testing errors caused by human observation of light intensity changes but also avoids interference from external light sources, effectively improving the accuracy of the release film's alignment angle test.

[0028] Beneficial effects:

[0029] (1) This utility model achieves full light source enclosure by using a light shield to avoid interference from external light sources, thereby avoiding the impact on test personnel, preventing errors in test results, and thus ensuring the accuracy of the orientation angle test.

[0030] (2) This utility model displays the intensity and brightness changes of the light source through an illuminance meter. The illuminance meter directly displays the brightness changes of the polarizer light source, avoiding the test error of human visual observation, thereby improving the accuracy of the orientation angle test.

[0031] (3) This utility model can improve the accuracy of orientation angle testing by making simple modifications based on the existing technology. The instrument cost is low, the testing method is simple, the testing efficiency is improved, and the technical problems of orientation angle testing in the current technology are effectively solved. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of a polarizer in the prior art;

[0033] Figure 2 This is a schematic diagram illustrating the principle of thin film bowing in existing technology;

[0034] Figure 3This is a three-dimensional structural schematic diagram (excluding the light shield) of the fully enclosed automatic measurement device for the alignment angle of the release film of this utility model.

[0035] Figure 4 This is a three-dimensional structural diagram of the light shield of this utility model;

[0036] Figure 5 This is a schematic diagram of the internal structure of the fully enclosed automatic measuring device for the alignment angle of the release film of this utility model (the arrows in the figure represent the direction of the light emitted by the light source).

[0037] Figure 6 This is a partially enlarged schematic diagram of the dial and rotating platform of this utility model (showing the 0 point scale of the dial and the indicator scale line of the rotating platform);

[0038] Figure 7 This is a graph showing the illuminance meter value versus the dial value of this utility model.

[0039] In the figure, 1 is the light source carrier plate, 2 is the first polarizer carrier plate, 3 is the bracket, 4 is the second polarizer carrier plate, 5 is the illuminance meter, 6 is the top plate, 7 is the support cylinder, 8 is the scale, 9 is the third light-transmitting hole, 10 is the rotating platform, 11 is the bolt, 12 is the first polarizer, 13 is the release film, 14 is the second polarizer, 15 is the photosensitive probe, 16 is the light shield, 17 is the wire, 18 is the groove, 19 is the protrusion, 20 is the protective film, 21 is the first TAC film, 22 is the PVA film, 23 is the second TAC film, 24 is the pressure-sensitive adhesive, and 25 is the release film. Detailed Implementation

[0040] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0041] Example 1

[0042] A fully enclosed automatic measuring device for the alignment angle of release films, such as Figures 3-5 As shown, it consists of a light source carrier plate 1, a light source, a first polarizer carrier plate 2, a bracket 3, a second polarizer carrier plate 4, an illuminance meter 5, a top plate 6, a support cylinder 7, a dial 8, a rotating platform 10, bolts 11, a first polarizer 12, a second polarizer 14, and a light shield 16.

[0043] The light source carrier plate 1, the first polarizer carrier plate 2, the second polarizer carrier plate 4, the top plate 6, the scale plate 8, the rotating platform 10, the first polarizer 12, and the second polarizer 14 are all arranged horizontally.

[0044] A light source (DC 24V / 5W LED lamp) is installed inside the light source carrier plate 1; a vertical first light-passing hole is provided at the center of the top of the light source carrier plate 1, and the first light-passing hole is located directly above the light source; the top surface of the light source carrier plate 1 is fixed to the bottom surface of the first polarizer carrier plate 2 by welding, and a vertical second light-passing hole is provided at the center of the first polarizer carrier plate 2, and the second light-passing hole is located directly above the first light-passing hole, and the first polarizer 12 covers the second light-passing hole; the top surface of the first polarizer carrier plate 2 is fixed to the bottom surface of the support cylinder 7 by welding; the top surface of the support cylinder 7 is detachably fixed to the bottom surface of the dial 8 by bolts 11; the rotating platform 10 is located at the center of the dial 8, and is rotatably connected to the dial 8 through a protrusion 19 and a groove 18, and the rotating platform 10 is provided with an indicator pointing to the dial 8. When the rotating platform 10 is turned, the rotating platform 10 rotates relative to the scale 8, and the scale line pointing to the scale 8 also changes accordingly. A vertical third light-transmitting hole 9 is provided at the center of the rotating platform 10, and the third light-transmitting hole 9 is located directly above the second light-transmitting hole and the first polarizer 12. The second polarizer carrier plate 4 is set above the rotating platform 10 and is supported by the top plate 6. The top plate 6 is fixedly connected to the light source carrier plate 1 through the bracket 3. A vertical fourth light-transmitting hole is provided at the center of the bottom of the second polarizer carrier plate 4, and the second polarizer 14 covers the fourth light-transmitting hole. The photosensitive probe 15 of the illuminance meter 5 is installed inside the second polarizer carrier plate 4 and is located directly above the fourth light-transmitting hole and the second polarizer 14. The display of the illuminance meter 5 is installed on the top of the second polarizer carrier plate 4.

[0045] The light emitted by the light source passes sequentially through the first light-transmitting hole, the second light-transmitting hole, the first polarizer 12, the third light-transmitting hole, the release film 13, the fourth light-transmitting hole, and the second polarizer 14 before being received by the photosensitive probe 15 of the illuminance meter 5. The photosensitive probe 15 of the illuminance meter 5 outputs the photosensitive signal to the display of the illuminance meter 5 through the wire 17. The display of the illuminance meter 5 displays the illuminance meter value, reflecting the information on the change in light intensity.

[0046] The light shield 16 is a cube formed by six stainless steel plates with polyimide film attached, used to cover the whole consisting of light source carrier plate 1, light source, first polarizer carrier plate 2, bracket 3, second polarizer carrier plate 4, illuminance meter 5, top plate 6, support cylinder 7, scale 8, rotating platform 10, first polarizer 12 and second polarizer 14.

[0047] The preparatory steps for using the above-mentioned fully enclosed automatic release film alignment angle measuring device are as follows:

[0048] (I) Turn on the detection equipment, avoid excessive ambient light, turn on the illuminance meter switch, check the working status of the illuminance meter, and observe the fluctuation range of its value.

[0049] (II) Align the indicator scale line of the rotating platform with the 0 point of the dial (the left side of the 0 point is considered the opposite direction). The 0 point scale of the dial and the indicator scale line of the rotating platform are as follows: Figure 6 As shown;

[0050] (III) Place the release film sample to be tested on the rotating platform and align it with the measurement edge;

[0051] (Ⅳ) Rotate the rotating platform. During the process of the scale value on the dial from 0 to 90°, first find the value of the illuminance meter that is larger during this process (for example, the illuminance meter displays a value of 260 Lux).

[0052] (V) According to Figure 7 The curve showing the illuminance meter value versus the dial value has the steepest slope when the illuminance meter's displayed value is close to half of its maximum value. This means that the illuminance meter's displayed value changes most sensitively when the meter rotates by 1°.

[0053] (VI) Rotate the rotating platform again. During the process of the dial value from 0 to 90°, slowly rotate to find the two positions where the display value of the lux meter is closest to 130 Lux. Record the dial value a and b at this time respectively.

[0054] (VII) Calculate the average value c of a and b. At c, the illuminance meter will detect its maximum value. Record the angle at which the rotating platform rotates. The absolute value of 45-c is the angle corresponding to the minimum value of the illuminance meter display.

[0055] Tests of the above-mentioned fully enclosed automatic measurement device for the alignment angle of release film:

[0056] Three release film samples were prepared, labeled as sample A, sample B, and sample C, respectively. The sample thickness was 23 μm. Different quality inspectors used the above-mentioned fully enclosed automatic release film orientation angle measuring device to test the orientation angle of sample A, sample B, and sample C. The results are shown in Table 1. As can be seen from Table 1, when the orientation angle was tested using the combination of the light shield and illuminance meter of this invention, the test results of different quality inspectors were basically the same.

[0057] Table 1 Test results of Example 1

[0058]

[0059] Comparative Example 1

[0060] Under fluorescent light, referring to patent CN217637239U, a dark field was manually found, and the same tester (quality inspector 1) was arranged to test the orientation angles of the three samples (sample A, sample B, and sample C) that were the same as in Example 1. The results are shown in Table 2.

[0061] Comparative Example 2

[0062] In a darkroom environment (simulating the fully enclosed situation of this utility model), referring to patent CN217637239U, a dark field was manually found, and the same tester (quality inspector 1) was arranged to test the orientation angles of three samples (sample A, sample B, and sample C) identical to those in Example 1. The deviation of the orientation angle test results of the same sample by the same tester under different light source environments was calculated, and the results are shown in Table 2.

[0063] Table 2 Test results for Comparative Example 1 and Comparative Example 2

[0064]

[0065] Comparative Examples 1 and 2 show that the deviation of the orientation angle test results of the same sample by the same tester under different light source environments is relatively large, ranging from 5% to 8%. This indicates that the presence of other light sources can cause a large error in the orientation angle test results, thus proving the importance of full sealing.

[0066] Comparative Examples 3-4

[0067] The results were basically the same as those for Comparative Example 1, except that the testers were Quality Inspector 2 and Quality Inspector 3, respectively. The test results for Comparative Example 1 and Comparative Examples 3-4 are shown in Table 3.

[0068] Table 3 shows the test results under fluorescent lamps for Comparative Examples 1 and 3-4.

[0069]

[0070] Comparative Examples 5-6

[0071] The results were basically the same as those for Comparative Example 2, except that the testers were Quality Inspector 2 and Quality Inspector 3, respectively. The test results for Comparative Example 2 and Comparative Examples 5-6 are shown in Table 4.

[0072] Table 4 shows the test results in the darkroom environment for Comparative Examples 2 and 5-6.

[0073]

[0074] From the above comparative examples, we can see that: (1) When different testers tested the orientation angle under fluorescent lamps and in a dark room, the test range of the three samples was smaller in the dark room environment. The stable trend indicates that the test results of the orientation angle are more stable under a fully enclosed light source; (2) Under the same test conditions, different testers had different test results for the same sample, indicating that the test process was greatly affected by human eye observation, resulting in a large test error; (3) The mean values ​​of the orientation angle were different under fluorescent lamps and in a dark room, indicating that different light sources affect the test results of the orientation angle, further corroborating the conclusions of comparative examples 1 and 2.

[0075] In summary, comparing the test results of Example 1 with those of Comparative Examples 1-6 demonstrates that the light shield of this invention avoids errors caused by external light source contamination, and its light-shielding effect is more significant than that of ordinary dark-field light shields. The illuminance meter sensitively and accurately displays the brightness changes of the polarizer light source, avoiding errors caused by human visual observation of these changes. Therefore, the combined design of the light shield and illuminance meter in this invention improves the accuracy of the release film alignment angle test.

Claims

1. A full-closed automatic measuring device for alignment angle of release film, comprising a main body part, the main body part comprising a light source, a first polarizer (12) and a second polarizer (14) arranged in sequence from bottom to top, the first polarizer (12) and the second polarizer (14) are both horizontally arranged, characterized in that, The main body part further comprises an illuminometer (5), a photosensitive probe (15) of the illuminometer (5) being located directly above a second polaroid (14); the off-type film alignment angle full-enclosed automatic measuring device further comprises a light shield (16), the light shield (16) being used to cover the main body part.

2. The device according to claim 1, wherein the device is characterized by, The main body part further comprises a light source carrier plate (1), a first polaroid carrier plate (2) and a second polaroid carrier plate (4), all of which are horizontally arranged; A light source is installed inside the light source carrier plate (1); a vertical first light transmission hole is arranged at the center of the top of the light source carrier plate (1), the first light transmission hole being located directly above the light source; A vertical second light transmission hole is arranged at the center of the first polaroid carrier plate (2), the first polaroid (12) covering the second light transmission hole; A vertical fourth light transmission hole is arranged at the center of the bottom of the second polaroid carrier plate (4), the second polaroid (14) covering the fourth light transmission hole; The top surface of the light source carrier plate (1) is connected with the bottom surface of the first polaroid carrier plate (2), the second light transmission hole being located directly above the first light transmission hole.

3. The device according to claim 2, wherein the device is characterized by: The photosensitive probe (15) of the illuminometer (5) is installed inside the second polaroid carrier plate (4) and located directly above the fourth light transmission hole.

4. The device according to claim 3, wherein the device is characterized by: The display of the illuminometer (5) is installed at the top of the second polaroid carrier plate (4).

5. The device according to claim 2, wherein the device is characterized by: The main body part further comprises a support cylinder (7), a scale disc (8) and a rotating platform (10); The scale disc (8) and the rotating platform (10) are both horizontally arranged; The top surface of the first polaroid carrier plate (2) is connected with the bottom surface of the support cylinder (7); the top surface of the support cylinder (7) is connected with the bottom surface of the scale disc (8); the rotating platform (10) is located at the center of the scale disc (8) and is rotationally connected with the scale disc (8); the rotating platform (10) is provided with an indicating scale line pointing to the scale disc (8); the rotating platform (10) is provided with a vertical third light transmission hole (9) at the center thereof, the third light transmission hole (9) being located directly above the second light transmission hole and the first polaroid (12); the second polaroid carrier plate (4) is arranged above the rotating platform (10).

6. The device according to claim 5, wherein the device is characterized by: The rotating platform (10) is rotationally connected with the scale disc (8) through a protrusion (19) and a groove (18).

7. The device according to claim 5, wherein the device is characterized by: The main body part further comprises a top plate (6) and a bracket (3); the top plate (6) is horizontally arranged; the second polaroid carrier plate (4) is supported by the top plate (6); the top plate (6) is connected with the light source carrier plate (1) through the bracket (3).

8. The device according to claim 1, wherein the device is a full-enclosed automatic measuring device for alignment angle of a release film. The light shield (16) is a cube surrounded by six stainless steel plates with polyimide film attached.

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