JP2005321217A - Polarizing plate inspection device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizing plate inspection device and a method capable of heightening inspection accuracy to 0.1 degree or less, and securing inspection quality at every time. <P>SOLUTION: This polarizing plate inspection device is equipped with a monochromatic light generation device for providing monochromatic light; a light receiving module installed oppositely to the monochromatic light generation device, for converting a light signal of the monochromatic light into readable data; and an adjustment stand provided between the monochromatic light generation device and the light receiving module, for placing a polarizing plate to be inspected and performing angle fine adjustment to the polarizing plate to be inspected. After passing the polarizing plate to be inspected, the monochromatic light is received by the light receiving module and measured. The polarizing plate inspection device is also provided with a fixing stand, and the fixing stand is provided between the monochromatic light generation device and the adjustment stand, and a polarization polarizing plate is placed thereon. The monochromatic light passes the polarization polarizing plate at first, to thereby form polarized monochromatic light. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a kind of polarizing plate inspection apparatus and method, and in particular, the accuracy of inspection reaches 0.1 degrees or less, and can provide an on-line real-time measurement function to achieve the purpose of rapid and accurate inspection. And a method.

  The liquid crystal display panel on the market has liquid crystal molecules between solid and liquid, and the liquid crystal molecules flow by the action of external force, and the liquid crystal alignment is modified by the electric field applied from the outside due to the crystal's unique optical anisotropy. In other directions, the optical characteristics when the light beam passes through the liquid crystal layer can be modified. That is, this is a decrease in modulation caused by a voltage applied from the outside, which is a so-called photoelectric effect of liquid crystal. Utilizing this effect, various liquid crystal display panels such as twisted nematic liquid crystal display panels, super twisted nematic liquid crystal display panels, and thin film transistor liquid crystal display panels are manufactured.

  FIG. 1 is an operation display diagram of a known twisted nematic liquid crystal display panel when no voltage is applied. FIG. 2 is an operation display diagram of a known twisted nematic liquid crystal display panel after voltage application. As shown in FIG. 1, the twisted nematic liquid crystal display 100 includes alignment films 110 and 120 in which ultrafine grooves 105 and 106 are formed by rubbing, and polarizing plates 130 and 140 that polarize scattered light directions. . When the nematic liquid crystal 150 is injected between the alignment films 110 and 120, the molecules of the nematic liquid crystal 150 have liquid fluidity, so that they are very easily aligned along the direction of the grooves 105 and 106. , 106, the binding force received by the nematic liquid crystal 150 is relatively large. Therefore, since the binding force received by the nematic liquid crystal 150 in the middle portion is relatively small, the twisting force is relatively small. The nematic liquid crystal 150 arranged and in the alignment films 110 and 120 is twisted by 90 degrees as a whole, and hence is called a nematic type. Accordingly, in a situation where no voltage is applied between the alignment films 110 and 120, the light beam 160 enters through the polarizing plate 140 and the alignment film 120, and its direction rotates 90 degrees with the alignment of the nematic liquid crystal 150. The polarization direction of the polarizing plate 130 is the same as that of the polarizing plate 130, so that the light passes smoothly through the polarizing plate 130.

  See further FIG. After a voltage is applied between the alignment films 110 and 120, the nematic liquid crystal 150 is parallel to the direction of the applied electric field (as shown), so that the nematic liquid crystal 150 is perpendicular to the surfaces of the alignment films 110 and 120, respectively. Thus, the direction of the light beam 160 does not rotate after entering the polarizing plate 140 and the alignment film 120, and therefore the light beam 160 cannot pass through the polarizing plate 130 after reaching the polarizing plate 130.

  Overall, the depression angle between the two polarizing plates 130 and 140 is 90 degrees, and the influence of the depression angle between the two polarizing plates 130 and 140 on the quality of the liquid crystal display panel is very large. The accuracy of is obviously important. All known adjustment methods are to purchase a separate machine and inspect the angle of each polarizing plate, but the degree of light analysis used is insufficient, so the error is usually more than 1 degree, and At the time of inspection, the polarizing plate had to be installed in the machine, which made the manufacturing flow more complicated and inconvenient.

In summary, the known polarizing plate inspection apparatus and method have at least the following deficiencies, and cannot ensure adjustment quality.
1. If the angle of the polarizing plate is inspected using a known machine, the accuracy of the inspection is insufficient and adjustment quality cannot be ensured.
2. When the angle of a polarizing plate is inspected using a well-known machine, the standard is limited to the machine standard to be inspected. When inspecting a polarizing plate of a different size, a different machine must be used, and the cost of the inspection And the situation where the inspection is performed with the wrong machine is likely to occur.
3. If the angle of the polarizing plate is inspected by using a known machine, the inspection cannot be completed by an online on-site work on site, and therefore the inspection efficiency is low and the production speed is reduced.
4). When the angle of the polarizing plate is inspected using a well-known machine, a new machine must be purchased when the standard size of the polarizing plate is changed, and a new training of the inspector is required. Increase the cost to bear.

  In view of the above-mentioned drawbacks of the prior art, the main object of the present invention is to provide a polarizing plate inspection apparatus and method, which can increase the accuracy of inspection to 0.1 degrees or less, It is assumed that the apparatus and method can ensure quality.

  Another object of the present invention is to provide a polarizing plate inspection apparatus and method, which can inspect polarizing plates of different standard sizes, reduce the cost of inspection, and reduce the incidence of errors. It shall be.

  Another object of the present invention is to provide a polarizing plate inspection apparatus and method, which can complete inspection by online on-site work in the field, increase the efficiency of the inspection, and increase the production speed. Assume apparatus and method.

  Still another object of the present invention is to provide a polarizing plate inspection apparatus and method, which eliminates the need to purchase an inspection machine or train an inspector even when the standard size of the polarizing plate is different. The inspection apparatus and method can be applied to reduce the cost burden of the company.

  According to a preferred embodiment of the polarizing plate inspection apparatus of the present invention, the polarizing plate inspection apparatus is provided with a monochromatic light generating device that provides monochromatic light, and is installed so as to face the monochromatic light generating device so that an optical signal of monochromatic light can be read. A light receiving module for converting data, a monochromatic light provided between the single color light generating device and the light receiving module, and an adjusting table for mounting a polarizing plate to be inspected and finely adjusting the angle of the polarizing plate to be inspected The light is received by the optical receiving module after passing through the inspected polarizing plate and measured.

  Among these, the polarizing plate inspection apparatus further includes a fixing base, and the fixing base is provided between the monochromatic light generating device and the adjustment base and mounts the polarizing polarizing plate. The monochromatic light generator is a laser system.

According to a preferred embodiment of the polarizing plate inspection method of the present invention, the polarizing plate to be inspected is provided on the adjustment table, and the polarizing plate inspection method is:
(A) a step of projecting monochromatic light onto a polarizing plate to be inspected at an appropriate angle;
(B) receiving monochromatic light that has passed through the inspected polarizing plate and obtaining a measurement value;
(C) comparing the measured value with the standard value;
(D) a step of rotating and adjusting the polarization angle of the polarizing plate to be inspected on the adjustment table, and approximating the measured value to the standard value;
It has the above steps.

The invention of claim 1 is the polarizing plate inspection apparatus,
A monochromatic light generator for providing monochromatic light;
A light receiving module that is installed to face the monochromatic light generator and converts the monochromatic light signal into legible data;
An adjusting table provided between the monochromatic light generating device and the light receiving module for placing the inspecting polarizing plate and finely adjusting the angle with respect to the inspecting polarizing plate;
The monochromatic light is received by the light receiving module after passing through the inspected polarizing plate.
A second aspect of the present invention is the polarizing plate inspection apparatus according to the first aspect, wherein the monochromatic light generator is a laser system.
The invention of claim 3 is the polarizing plate inspection method,
(A) a step of projecting monochromatic light onto a polarizing plate to be inspected at an appropriate angle;
(B) receiving monochromatic light that has passed through the inspected polarizing plate and obtaining a measurement value;
(C) comparing the measured value with the standard value;
(D) a step of rotating and adjusting the polarization angle of the polarizing plate to be inspected on the adjustment table, and approximating the measured value to the standard value;
A polarizing plate inspection method characterized by comprising the above steps.
A fourth aspect of the present invention is the polarizing plate inspection method according to the third aspect, wherein the monochromatic light is laser light.
The invention of claim 5 is the polarizing plate inspection apparatus,
A moving support frame;
A monochromatic light generator provided on the movable support frame to provide monochromatic light;
An optical receiver module provided on the movable support frame and disposed so as to face the monochromatic light generator, and converts the monochromatic optical signal into legible data;
A polarizing plate to be inspected is provided between the monochromatic light generating device and the light receiving module, and the monochromatic light generating device and the light receiving module move so as to correspond to each other. The polarizing plate inspection apparatus is characterized by being received by the optical receiving module after passing through.
A sixth aspect of the present invention is the polarizing plate inspection apparatus according to the fifth aspect, wherein the monochromatic light generator is a laser system.
The invention of claim 7 is the polarizing plate inspection method,
(A) A step of axially scanning the polarizing plate to be inspected with monochromatic light,
(B) receiving monochromatic light that has passed through the inspection polarizing plate and obtaining a plurality of measurement values;
(C) comparing a plurality of measurements with a database;
The polarizing plate inspection method is characterized by comprising the above steps.
The invention of claim 8 is the polarizing plate inspection method according to claim 7, characterized in that the monochromatic light is laser light.

  The polarizing plate inspection apparatus and method of the present invention can reduce the accuracy of inspection to 0.1 degrees or less, can inspect polarizing plates of different standard sizes, and can complete the inspection through online integrated work in the field. Effectively increase the efficiency of inspection, increase the production speed, and reduce the company's cost burden without the need to purchase extra inspection machines or newly train inspectors.

  According to the first embodiment of the polarizing plate inspection apparatus of the present invention shown in FIG. 3, the polarizing plate inspection apparatus of the present invention provides monochromatic light by the monochromatic light generator 200, and the present invention generates a monochromatic light. Used as device 200. The laser light 206 generated by the laser system is visible light, and the laser light 206 has characteristics of high resolution, high brightness, and high purity, and the wavelength of the laser light 206 can be controlled from 380 nm to 780 nm, that is, visible light. Since the wavelength can be set to the wavelength, the inspector can clearly see the generated waveform, and the resolution of the laser beam 206 reaches 0.01 nm. The degree reaches below 0.1 degree.

  Subsequently, the laser beam 206 is projected toward the polarization polarizing plate 201 placed on the fixed base 2010. The fixed table 2010 is provided between the monochromatic light generator 200 and the adjusting table 2020, and the laser beam 206 changes its polarization direction after passing through the polarizing plate 201 and becomes the same as the polarizing plate 201, and The fixed table 2010 is maintained at a fixed position, and the polarization direction of the laser beam 206 is always the same during measurement. The polarized laser beam 206 is projected onto the inspecting polarizing plate 202 placed on the adjusting table 2020, and the adjusting table 2020 can finely adjust the angle with respect to the inspecting polarizing plate 202, that is, the inspecting polarizing plate 202. The polarization angle can be adjusted. The polarized laser beam 206 is finally received by the optical receiver module 203, and the optical receiver module 203 is installed so as to face the monochromatic light generator 200, and converts the optical signal of the laser beam 206 into legible data.

  In general, the optical receiver module 203 is composed of an optical capture unit 2031 and an optical signal detector 2032, of which the optical capture unit 2031 receives laser light 206, and is most often used as a charge coupled device (CCD), complementary A MOS (CMOS) or a photomultiplier tube (PMT). The optical signal detector 2032 normally converts the optical signal of the laser beam 206 received by the optical capture unit 2031 into readable data, so that a wave detector is usually used. The optical receiving module 203 is connected to a computer 205 as a recording contrast device. The computer 205 records and compares data from the optical receiving module 203, and further adjusts the polarization angle of the inspected polarizing plate 202 controlled by the adjusting table 2020. Control.

Please refer to FIG. 4 and FIG. FIG. 4 is a flowchart of a preferred embodiment of the polarizing plate inspection method of the present invention, and FIG. 5 is an intensity-angle correspondence diagram of the preferred embodiment of the polarizing plate inspection method of the present invention. Among these, the polarizing plate to be inspected is provided on the adjusting table, and the polarizing plate inspection method of the present invention includes the following steps.
(A) The monochromatic light is projected onto the inspected polarizing plate at an appropriate angle (400). Of these, the monochromatic light is laser light, the wavelength is 380 to 780 nm, the resolution is 0.01 nm, and the appropriate angle refers to the light after polarization, which can be set to 90 degrees or 0 degrees.
(B) The monochromatic light that has passed through the inspection polarizing plate is received to obtain a measurement value (401). The measured value is similar to the It curve in FIG. 6. This It curve is obtained by converting the optical signal of the laser beam into data that can be received and read by the optical receiving module. Is read, and an intensity-angle correspondence diagram is drawn to know how much the light intensity signal is at which angle.
(C) The measured value is compared with the standard value (402). The standard value is like the Is curve in FIG. 6, which is standard data corresponding to the intensity-angle of the standard polarizing plate, and the polarization angle of the standard polarizing plate used in this example is 90 degrees. The Is curve in 6 has the maximum intensity at 90 degrees and the minimum intensity at 0 degrees or 100 degrees.
(D) The polarization angle of the polarizing plate to be inspected is rotated and adjusted on the adjustment table to approximate the measured value to the standard value (403). The polarization angle of the polarizing plate to be inspected is adjusted using the adjusting table. At this time, when the It curve in FIG. 6 approaches the Is curve slowly and the It curve approximates the Is curve, the polarized light to be inspected The polarization angle of the plate approximates 90 degrees. At this time, a symbol can be formed on the inspected polarizing plate to obtain the inclining angle of the inspecting polarizing plate. Therefore, the polarizing plate of any size standard can be inspected. The

  FIG. 6 shows a second embodiment of the polarizing plate inspection apparatus of the present invention. Also in this embodiment, the monochromatic light generating apparatus 500 uses a laser system, and its function is similar to that of the first embodiment, and therefore description thereof is omitted. In addition, since the function of the polarizing plate 504 is also similar to that of the polarizing plate 201, description thereof is omitted. Among them, the inspected polarizing plate 502 is provided on the transport rollers 503a and 503b, and the inspected polarizing plate 502 is sent online from the transport roller 503a to the transport roller 503b. Among them, the monochromatic light generator 500 on the moving support frame 504 and the corresponding light receiving module 505 move corresponding to each other, and the laser light 507 is scanned by the light receiving module and then received by the light receiving module 505. The receiving module 505 converts the optical signal of the laser beam 507 into legible data, and further sends it to the computer 506 for comparison. The computer 506 also sends cutting angle information to the cutter 508 to determine the cutting angle of the cutter 508. Thus, it is possible to complete the on-line on-site inspection in the field, effectively increase the inspection efficiency, and increase the production speed.

FIG. 7 is a flowchart of a second embodiment of the polarizing plate inspection method of the present invention, which has the following steps.
(A) The inspection polarizing plate is scanned in the axial direction with monochromatic light (600). Among these, the monochromatic light is laser light, the wavelength is 380 nm to 780 nm, the resolution is 0.01 nm or more, and the axial direction is the radial axial direction of the polarizing plate to be inspected. Usually, since the width of the polarizing plate to be inspected is about 130 cm, optical signals at different points on the inspecting polarizing plate can be obtained by the axial scanning.
(B) The monochromatic light that has passed through the inspection polarizing plate is received, and a plurality of measured values are obtained (601). The optical signal of laser light (monochromatic light) is converted into legible data using an optical receiver module. Since the laser beam scans the polarizing plate to be inspected by a method of scanning in the radial axis direction, the optical signal passing through different points of the polarizing plate to be inspected can be converted into measured values at a plurality of different points, and subsequent comparison judgment To serve.
(C) The above-mentioned plurality of measured values are compared with the database (602). The measured values at a plurality of different points obtained as described above are compared with a database in the comparison device. The data in the database is intensity-angle data of polarizing plates of various standard polarization angles. After the cross-contrast, the angle distribution of the polarizing plate to be inspected (usually, the angle of the entire polarizing plate to be inspected includes an allowable error Get).
(D) The polarizing plate to be inspected is cut with a cutter (603). After obtaining the angle distribution of the polarizing plate to be inspected in the step (c), the cutting angle of the cutter is adjusted, and the polarizing plate to be inspected is cut to obtain a necessary angle. The accuracy is increased, and the accuracy is set to 0.1 degrees or less.

  In summary, the polarizing plate inspection apparatus and method of the present invention can reduce the accuracy of inspection to 0.1 degrees or less, and can inspect polarizing plates of different standard sizes, as well as on-line integrated work in the field. Can complete the inspection, effectively increase the efficiency of inspection, increase the production speed, and reduce the company's cost burden without the need to purchase extra inspection machines or newly train inspectors . It should be noted that the above embodiments do not limit the scope of the present invention, and modifications that can be made based on the present invention, for example, using polarized light with different polarization angles, omitting polarization polarizing plates, and rotating the adjusting table Any change in direction or the like belongs to the claims of the present invention.

FIG. 6 is an operation display diagram when a known twisted nematic liquid crystal display panel is not applied with an external voltage. It is an operation | movement display figure at the time of the external voltage application of a well-known twisted nematic type liquid crystal display panel. It is a 1st Example display figure of the polarizing plate test | inspection apparatus of this invention. It is a 1st Example flowchart of the polarizing plate inspection method of the present invention. It is intensity | strength-angle corresponding | compatible figure of 1st Example of the polarizing plate test | inspection method of this invention. It is a 2nd Example display figure of the polarizing plate test | inspection apparatus of this invention. It is a 2nd Example flowchart of the polarizing plate inspection method of this invention.

Explanation of symbols

100 twisted nematic type liquid crystal display panel 105, 106 groove 110, 120 alignment film 130, 140 polarizing plate 150 liquid crystal 160 light 200 monochromatic light generator 206 laser light 2010 fixing base 201 polarizing polarizing plate 2020 adjusting base 202 inspection polarizing plate 203 light Reception module 2031 Optical capture unit 2032 Optical signal detection device 205 Computer 500 Monochromatic light generation device 501 Polarizing polarizing plates 503a and 503b Transport rollers 502 Inspected polarizing plate 504 Moving support frame 505 Optical reception module 5051 Optical capture unit 5052 Optical signal detection device 506 Computer 507 Laser beam 508 Cutter 400 Projects monochromatic light onto the inspecting polarizing plate at an appropriate angle 401 Receives monochromatic light that has passed through the inspecting polarizing plate and obtains measurement values 402 Measurement 403 Rotate and adjust the polarization angle of the polarizing plate to be inspected with an adjustment table to make the measured value approximate to the standard value 600 Scan the polarizing plate to be inspected axially with monochromatic light 601 Receiving the passed monochromatic light to obtain a plurality of measurement values 602 Comparing a plurality of measurement values with a database 603 Cutting a polarizing plate to be inspected with a cutter

Claims (8)

In polarizing plate inspection equipment,
A monochromatic light generator for providing monochromatic light;
A light receiving module that is installed to face the monochromatic light generator and converts the monochromatic light signal into legible data;
An adjusting table provided between the monochromatic light generating device and the light receiving module for placing the inspecting polarizing plate and finely adjusting the angle with respect to the inspecting polarizing plate;
And the monochromatic light is received by the light receiving module after passing through the inspected polarizing plate.   2. The polarizing plate inspection apparatus according to claim 1, wherein the monochromatic light generator is a laser system. In the polarizing plate inspection method,
(A) a step of projecting monochromatic light onto a polarizing plate to be inspected at an appropriate angle;
(B) receiving monochromatic light that has passed through the inspected polarizing plate and obtaining a measurement value;
(C) comparing the measured value with the standard value;
(D) a step of rotating and adjusting the polarization angle of the polarizing plate to be inspected on the adjustment table, and approximating the measured value to the standard value;
A polarizing plate inspection method comprising the above steps.   4. The polarizing plate inspection method according to claim 3, wherein the monochromatic light is laser light. In polarizing plate inspection equipment,
A moving support frame;
A monochromatic light generator provided on the movable support frame to provide monochromatic light;
An optical receiver module provided on the movable support frame and disposed so as to face the monochromatic light generating device, and converts an optical signal of monochromatic light into legible data;
A polarizing plate to be inspected is provided between the monochromatic light generating device and the light receiving module, and the monochromatic light generating device and the light receiving module move so as to correspond to each other. A polarizing plate inspection apparatus, which is received by the optical receiving module after passing through.   6. The polarizing plate inspection apparatus according to claim 5, wherein the monochromatic light generator is a laser system. In the polarizing plate inspection method,
(A) A step of axially scanning the polarizing plate to be inspected with monochromatic light,
(B) receiving monochromatic light that has passed through the inspection polarizing plate and obtaining a plurality of measurement values;
(C) comparing a plurality of measurements with a database;
A polarizing plate inspection method comprising the above steps. The polarizing plate inspection method according to claim 7, wherein the monochromatic light is laser light.

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