WO2014180047A1

WO2014180047A1 - Detection method and detection apparatus for front and reverse surfaces of polarizer

Info

Publication number: WO2014180047A1
Application number: PCT/CN2013/078192
Authority: WO
Inventors: 赵国栋; 宋涛; 刘明; 马涛; 陈方甫
Original assignee: 深圳市华星光电技术有限公司
Priority date: 2013-05-09
Filing date: 2013-06-27
Publication date: 2014-11-13
Also published as: CN103278946B; CN103278946A

Abstract

A detection method for front and reverse surfaces of a polarizer (20). The detection method comprises steps of: setting first marks (22) on two corners that are on one diagonal line on a front or reverse surface of the polarizer (20); detecting one corner on the front or reverse surface of the polarizer (20) by using a sensor (31); determining, by using an identification apparatus (32), whether a correct first mark (22) exists; and if the correct first mark exists, bonding the polarizer (20) to a liquid crystal display panel, or if the correct first mark does not exist, stopping bonding. In the detection method for the front and reverse surfaces of the polarizer (20), the marks on the polarizer (20) are checked, to confirm whether the front surface or the reverse surface of the polarizer (20) is placed reversely, and whether the checked polarizer (20) is a polarizer (20) of another model and having the same size, thereby avoiding wastes of the polarizer (20), reducing production costs, and improving the yield. A detection apparatus for the front and reverse surfaces of the polarizer (20) is further disclosed.

Description

Description method and detection device for front and back of polarizing plate

TECHNICAL FIELD The present invention relates to the field of liquid crystal panel manufacturing. More specifically, it relates to a detecting method and a detecting device for the front and back surfaces of a polarizing plate. Background technique

In the field of liquid crystal panel manufacturing, for example, in the fabrication process of VA-type panels such as TN panels, MVA, and PVA, polarizing plate attachment is required. The polarizing plate is used to control the light to pass in a specific direction, and then the liquid crystal has an optical rotation effect on the polarized light, thereby achieving selective passage of light, thereby causing the liquid crystal panel to display different images. The polarizing plate has a polarization axis in a specific direction, which requires polarizing plate attachment in accordance with the direction of the specified polarization axis. In addition, the polarizing plate has a front and back surface, wherein the front surface of the polarizing plate is a non-adhesive protective film surface, and the reverse side of the polarizing plate is a release paper surface having a rubber layer. When attaching the polarizing plate, it is necessary to tear off the release paper first, and attach the adhesive layer to the glass, so that the front and back sides must be distinguished when the polarizing plate is attached. At the same time, due to the market demand, it is often necessary to use different types of polarizing plates for LCD panels of the same size, so it is also necessary to distinguish polarizing plates of the same size but different types. At present, in the production process of a polarizing plate, marks of different colors or shapes are usually printed on a corner of the front surface of the polarizing plate to distinguish the front and back faces of the polarizing plate, the direction of the polarizing axis, and the type of the polarizing plate. However, such marks are generally only used for human eye recognition, which results in the polarizing plate attaching process of the liquid crystal panel. If the polarizing plate is reversed, or the same size but different types of polarizing plates are placed incorrectly, it is impossible to It is effectively monitored, thus causing waste of the polarizing plate, increasing the production cost, and reducing the yield of the product. Summary of the invention

In order to solve the above problems in the prior art, it is an object of the present invention to provide a method for detecting the front and back surfaces of a polarizing plate, and the detecting method can also detect the type of the polarizing plate. According to an aspect of the present invention, a method for detecting front and back surfaces of a polarizing plate includes: arranging a first mark on two corners of a front side or a reverse side of a polarizing plate; and detecting a polarizing plate by using a sensor a corner on the front or back side; using the identification device to determine whether it is the correct first mark; and if so, bonding the polarizing plate to a liquid crystal panel, and if not, stopping the bonding. In addition, a second mark is also disposed at one of two corners of the front side or the opposite side of the polarizing plate, wherein the sensor detects the second mark or cannot detect any mark. When the identification device determines that the detection result is an incorrect first mark, the bonding of the polarizer to the liquid crystal panel is stopped. In addition, a second mark is respectively disposed at two corners of the front side or the opposite side of the polarizing plate; when the sensor detects the second mark, the identifying device determines that the second mark is not correct. The first mark stops the bonding of the polarizer to the liquid crystal panel. In addition, the sensor is a charge coupled device image sensor. After detecting a corner on the front or back surface of the polarizing plate, the sensor transmits the detection result to the identification device for determination. In addition, the sensor is an optical sensor and the first mark has a reflection characteristic or a transmission characteristic. After the sensor detects a corner on the front side or the reverse side of the polarizing plate, the detection result is transmitted to the identification device for determination. In addition, the first identifier is a model for identifying different polarizers. Further, the shape of the first mark is different from the shape of the second mark. Further, the shape of the first mark is the same as the shape of the second mark, and the size of the second mark is different from the size of the first mark. In addition, the sensor is an optical sensor and each of the first mark and the second mark has a reflection characteristic or a transmission characteristic. After detecting a corner on the front side or the reverse side of the polarizing plate, the sensor transmits the detection result to the identification device. Judge. Furthermore, the two first marks are centrally symmetrical to each other. Furthermore, the two first marks are centrally symmetrical to each other and the two second marks are centrally symmetrical to each other. Another object of the present invention is to provide a detecting device for front and back of a polarizing plate, comprising: an adsorption device for adsorbing and transmitting the polarizing plate; and a detecting device for detecting a mark on the polarizing plate And inputting the marked information to the identification device; the identification device is configured to determine the received from the detecting device Whether the marked information is consistent with the predetermined marked information. Furthermore, the detection device comprises a charge coupled device image sensor. Further, the detecting device further includes an alarm device that issues an alarm signal when the information of the tag received by the recognition device does not coincide with the information of the predetermined tag. The detecting method and the detecting device for the front and back surfaces of the polarizing plate of the present invention check whether the front and back surfaces of the polarized plate to be inspected are reversed by checking the mark on the polarizing plate, and whether the polarized plate to be inspected is of another type of the same size. The polarizing plate avoids the waste of the polarizing plate, reduces the production cost, and improves the yield of the product. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic view of a detecting device for a front and back surface of a polarizing plate and a model thereof according to Embodiment 1 of the present invention. 2 and 3 are schematic views respectively showing the detecting device using the optical sensor and detecting the front and back faces of the polarizing plate and its model number according to Embodiment 1 of the present invention. 4 is a schematic view of a detecting device of a front and back surface of a polarizing plate and a model thereof according to Embodiment 2 of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION The embodiments of the present invention will now be described in detail, and in the accompanying drawings, The embodiments are described below to explain the present invention by referring to the figures. In the drawings, the thickness of layers and regions may be exaggerated for clarity. In the following description, unnecessary details of well-known structures and/or functions may be omitted in order to avoid obscuring the inventive concept of the present invention. Embodiment 1 FIG. 1 is a schematic view of a detecting device for a front and back surface of a polarizing plate and a model thereof according to Embodiment 1 of the present invention. Referring to Fig. 1, the detecting device of the present embodiment includes an adsorbing device 10, and the adsorbing device 10 adsorbs a polarizing plate 20, wherein, in order to avoid horizontal rotation of 180 degrees when the adsorbed polarizing plate 20 is placed (the polarizing plate 20 is rotated by 180 degrees, In the case where the optical rotation is affected, the mark is not detected, and the detecting device mistakenly believes that the polarizing plate 20 is placed incorrectly, and therefore, the diagonal line 21 on the front side or the reverse side of the polarizing plate 20 (Fig. The two corners pointing in the middle point are respectively provided with the first mark 22, and in order to prevent the correct mark from being detected after the polarizing plate 20 is horizontally rotated by 180 degrees, preferably, the two first marks 22 are centrally symmetrical with each other. That is, when one of the first marks 22 is rotated by 180 degrees from its center point, it completely coincides with the other first mark 22. It should be understood that the first mark 22 may also be respectively disposed at two corners of the front surface or the reverse side of the polarizing plate 20 which are pointed by the other diagonal line intersecting the diagonal line 21. In the present embodiment, the first marks 22 are respectively disposed at two corners of the front surface of the polarizing plate 20, and the two first marks 22 are centrally symmetrical with each other, and the shape of the first mark 22 is "A". ". The adsorption device 10 reaches the bonding area via the path L. The detection area 30 is disposed on the path L. After the adsorption device 10 adsorbs the polarizing plate 20, it proceeds along the path L, and the polarizing plate 20 is detected in the detecting area 30. The detecting area 30 includes at least one sensor 31. The sensor 31 is disposed above or below the polarizing plate 20 of the detecting area 30 according to the first mark 22 disposed on the front or back side of the polarizing plate 20, and the sensor 31 detects the polarizing plate 20. The first mark 22; in this embodiment, the sensor 31 is fixedly disposed above the polarizing plate 20 reaching the detecting area 30, which can only detect one corner of the polarizing plate 20, and the sensor 31 includes a charge coupled device image sensor ( CCD), after receiving the "A" pattern, the CCD transmits the "A" pattern to the identification device 32 for determination, the identification device 32 determines that the first mark 22 is correct, and the adsorption device 10 continues to transport the polarizing plate 20 to the bonding area. It is attached to a liquid crystal panel (not shown). If the sensor 31 cannot detect any mark, that is, the polarizing plate 20 is flipped 180 degrees, and the front and back sides of the polarizing plate 20 are reversed, the identification device 32 does not receive the judgment pattern, and the identification device 32 will determine that the first is incorrect. Indicia 22, therefore, the detecting device of the present embodiment does not allow the polarizing plate 20 to be fed to the bonding area to be bonded to the liquid crystal panel. The detecting device of this embodiment issues a warning and discharges the erroneous polarizing plate 20 for inspection. Further, the above-described sensor 31 may be an optical sensor. The details will be described below. 2 and 3 are schematic views respectively showing the detecting device using the optical sensor and detecting the front and back faces of the polarizing plate and its model number according to Embodiment 1 of the present invention. Referring to Fig. 2, the first flag of the optical sensor using the transmission characteristic detection will be described. When the sensor is the optical sensor 41, the first mark 42 is a mark having a transmission characteristic. After the optical sensor 41 detects the first mark 42, the value of the transmission characteristic of the first mark 42 is used to obtain a value, and the value is transmitted to the identification device 43 for determination. If the identification device 43 determines that the first mark 42 is correct, the polarizing plate 20 is transmitted to the bonding area; if the identification device 43 determines that the first mark 42 is incorrect, the transmission of the polarizing plate 20 to the bonding is stopped. Area. The detecting device of this embodiment issues a warning and discharges the erroneous polarizing plate 20 for inspection. Referring to Fig. 3, the first sensor will be described using the reflection characteristic of the optical sensor. When the sensor is the optical sensor 51, the first mark 52 is a mark having a reflection characteristic. After the optical sensor 51 detects the first mark 52, the value of the reflectance of the reflection characteristic on the first mark 52 is used to obtain a value, and the value is transmitted to the identification device 53 for determination. If the identification device 53 determines that the first mark 52 is correct, the polarizing plate 20 is transmitted to the bonding area; if the identification device 53 determines that the first mark 52 is incorrect, the transmission of the polarizing plate 20 to the bonding is stopped. Area. The detecting device of this embodiment issues a warning and discharges the erroneous polarizing plate 20 for inspection. Embodiment 2 FIG. 4 is a schematic view of a detecting device for a front and back surface of a polarizing plate and a model thereof according to Embodiment 2 of the present invention. Referring to FIG. 4, in the second embodiment, compared with the first embodiment, the first mark 22 may be respectively disposed at two corners of the front surface or the opposite side of the diagonal line 21 of the polarizing plate 20, and at the same time as the polarizing plate 20 One of the two corners pointed by the diagonal line 61 intersecting the diagonal line 21 on the front or the back side is provided with the second mark 62 or the two corners are respectively provided with the second mark 62. In the present embodiment, the first marks 22 are respectively disposed at two corners pointed by the diagonal 21 of the front surface of the polarizing plate 20, and the two first marks 22 are centrally symmetrical with each other while being diagonally opposite to the front surface of the polarizing plate 20. A second mark 62 is provided at one of the two corners pointed by the line 61. The shape of the second mark 62 is different from the shape of the first mark 22; alternatively, the shape of the second mark 62 is the same as the shape of the first mark 22, but the sizes of the two are different, for example, the lateral size of the second mark 62 is smaller than Or greater than the lateral dimension of the first indicia 22, or the longitudinal dimension of the second indicia 62 is less than or greater than the longitudinal dimension of the first indicia 22. In the present embodiment, the shape of the first mark 22 is "A", and the shape of the second mark 62 is "B". When the sensor 31 detects the "A" pattern, the "A" pattern is transmitted to the identification device 32 for determination, the identification device 32 determines that the first mark 22 is correct, and the adsorption device 10 continues to transport the polarizing plate 20 to the bonding area. It is attached to a liquid crystal panel (not shown). If the sensor 31 cannot detect any mark or detects a "B" pattern (here, it should be noted that when the second mark 62 is respectively disposed at two corners of the front side of the polarizing plate 20, the sensor 31 is provided. Only the "B" pattern is detected, and the two second marks 62 are center-symmetrical with each other, that is, one second mark 62 is rotated 180 degrees from its center and completely coincides with the other second mark 62, that is, the polarizing plate 20 When it is flipped 180 degrees and the front and back sides of the polarizing plate 20 are reversed, the identification device 32 will judge that it is not Correct first mark 22. Therefore, the detecting device of the present embodiment does not allow the polarizing plate 20 to be sent to the bonding area to be bonded to the liquid crystal panel. The detecting device of this embodiment issues a warning and discharges the erroneous polarizing plate 20 for inspection. In this embodiment, the sensor 31 may be a charge coupled device image sensor (CCD), and the operation process thereof is the same as that described in Embodiment 1, and details are not described herein again. The sensor 31 may be an optical sensor that detects the transmission characteristic or the reflection characteristic of the mark. Correspondingly, the first mark 22 and the second mark 62 have a transmission characteristic or a reflection characteristic, and the operation process of the optical sensor is the same as that described in Embodiment 1. , will not repeat them here. In addition, in the above embodiments, the first mark or the second mark may be set to a plurality of patterns such as a circle, a rectangle, a star, or a triangle, or may be set as an English letter (for example, A, B, C, etc. The pattern, the invention is not limited thereto. In addition, it should be noted that, in the above embodiments, the first mark is used to identify the model of the different polarizing plates. Moreover, for different types of polarizing plates of the same size, the first marks of different shapes or different sizes are used for marking. In summary, by checking the mark on the polarizing plate, it is confirmed whether the front and back sides of the polarized plate to be inspected are reversed, and whether the polarized plate to be inspected is a polarizing plate of another type of the same size, thereby avoiding waste of the polarizing plate. , reducing production costs and increasing product yield. Although the present invention has been particularly shown and described with reference to the exemplary embodiments thereof, those skilled in the art Various changes on it.

Claims

Claim

A method for detecting front and back sides of a polarizing plate, comprising: step: respectively setting a first mark on two corners of a front side or a reverse side of the polarizing plate; and detecting a front side of the polarizing plate by using a sensor a corner on the reverse side; using the identification device to determine whether it is the correct first mark; and if so, bonding the polarizing plate to a liquid crystal panel, and if not, stopping the bonding.

2. The detecting method according to claim 1, wherein a second mark is further disposed at one of two corners of the front side or the opposite side of the polarizing plate, wherein the sensor detects When the second mark is not detected or any mark is not detected, the identification device determines that the detection result is an incorrect first mark, and stops the bonding of the polarizer to the liquid crystal panel.

The detecting method according to claim 1, wherein a second mark is further disposed at two corners of the front side or the opposite side of the polarizing plate, respectively; when the sensor detects the second mark When the identification device determines that the second mark is not the correct first mark, the bonding of the polarizer to the liquid crystal panel is stopped.

4. The detecting method according to claim 1, wherein the sensor is a charge coupled device image sensor, and the sensor detects a corner on the front or back side of the polarizing plate, and transmits the detection result to the identification device. Judge.

The detecting method according to claim 1, wherein the sensor is an optical sensor and the first mark has a reflection characteristic or a transmission characteristic, and the sensor detects a corner on the front side or the reverse side of the polarizing plate, and then detects The measurement result is transmitted to the identification device for judgment.

The detecting method according to claim 2, wherein the first identifier is a model for identifying different polarizing plates.

7. The detecting method according to claim 3, wherein the first identifier is a model number for identifying different polarizing plates.

The detecting method according to claim 2, wherein the shape of the first mark is different from the shape of the second mark.

9. The detecting method according to claim 3, wherein the shape of the first mark is different from The shape of the second mark is described.

The detecting method according to claim 2, wherein the shape of the first mark is the same as the shape of the second mark, and the size of the second mark is different from the size of the first mark.

The detecting method according to claim 3, wherein the shape of the first mark is the same as the shape of the second mark, and the size of the second mark is different from the size of the first mark.

The detecting method according to claim 2, wherein the sensor is an optical sensor and each of the first mark and the second mark has a reflection characteristic or a transmission characteristic, and the sensor detects one of a front side or a reverse side of the polarizing plate After the corner, the detection result is transmitted to the identification device for judgment.

The detecting method according to claim 3, wherein the sensor is an optical sensor and each of the first mark and the second mark has a reflection characteristic or a transmission characteristic, and the sensor detects one of a front side or a reverse side of the polarizing plate After the corner, the detection result is transmitted to the identification device for judgment.

14. The detecting method according to claim 1, wherein the two first marks are center-symmetrical to each other.

15. The detecting method according to claim 2, wherein the two first marks are center-symmetrical to each other.

16. The detecting method according to claim 3, wherein the two first marks are center-symmetrical to each other, and the two second marks are center-symmetrical to each other.

17. A detecting device for front and back sides of a polarizing plate, comprising: an adsorbing device for adsorbing and transmitting the polarizing plate; and a detecting device for detecting a mark on the polarizing plate and inputting the marked information The identification device is configured to determine whether the information of the mark received from the detecting device is consistent with the information of the predetermined mark.

18. The detecting device according to claim 17, wherein the detecting device comprises a charge coupled device image sensor.

The detecting device according to claim 17, wherein the detecting device further comprises an alarm device that issues an alarm signal when the information of the tag received by the recognizing device does not coincide with the information of the predetermined tag.