WO2014196476A1

WO2014196476A1 - Defect inspection system and film production apparatus

Info

Publication number: WO2014196476A1
Application number: PCT/JP2014/064472
Authority: WO
Inventors: 圭太井村
Original assignee: 住友化学株式会社
Priority date: 2013-06-04
Filing date: 2014-05-30
Publication date: 2014-12-11
Also published as: TW201510512A; JP2014235123A; KR20160014630A; CN105308441B; TWI629466B; KR20190108655A; CN105308441A; JP6182806B2

Abstract

This defect inspection system includes: lamination rolls for laminating a first film and a second film to form a film; a transport line to the downstream side from the lamination rolls, for transporting the film; a defect inspection apparatus situated on the transport line; and a recording apparatus situated on the transport line to the downstream side from the defect inspection apparatus, for recording onto the film defect information relating to defects detected by the defect inspection apparatus. The defect inspection apparatus is located on the transport line to the upstream side from the roll that, apart from the lamination rolls, initially contacts the second film on the surface on the opposite side from the first film.

Description

Defect inspection system and film manufacturing apparatus

The present invention relates to a defect inspection system and a film manufacturing apparatus.
This application claims priority based on Japanese Patent Application No. 2013-117947 filed on June 4, 2013, the contents of which are incorporated herein by reference.

As a strip-shaped film defect inspection system, a defect inspection system described in Patent Document 1 is known. The defect inspection system of Patent Document 1 includes a defect inspection device and a recording device that records defect information on a film on a film conveyance line.
On the other hand, a film manufacturing apparatus described in Patent Document 2 is known as a film manufacturing apparatus. The film manufacturing apparatus of Patent Document 2 includes a bonding roll that bonds the first film and the second film to form a film, a transport line that transports the film on the downstream side of the bonding roll, and a transport line. And a defect inspection apparatus provided in the apparatus.

For example, in a film production line, a first film and a second film are bonded together and wound into a roll to produce a film roll. When laminating the first film and the second film, the inclusion of foreign substances such as bubbles may occur between the first film and the second film. The defect inspection apparatus inspects for the presence or absence of foreign matter defects between the first film and the second film.

Japanese Unexamined Patent Publication No. 2011-7779 Japanese Unexamined Patent Publication No. 2008-49604

Defect inspection equipment is usually installed on the downstream side of the transport line. This is because if the defect inspection apparatus is provided on the downstream side of the conveyance line rather than the upstream side of the conveyance line, defects such as scratches generated on the film during conveyance can be collectively inspected. For example, the defect inspection apparatus inspects the film for defects after contacting the rolls of 10 to 20.

On the other hand, when the second film is peeled from the first film in the final product, the scratch on the surface of the second film is not a problem. For example, even if the surface of the second film is scratched, if there is no foreign matter defect between the first film and the second film, the film can be used as a final product without problems.

However, if there is a scratch on the surface of the second film while the film is being transported, a scratch on the surface of the second film that is not a problem may be erroneously detected as a defect. In this case, a film that can be used as a final product is recognized as a defective product.

The aspect of the present invention has been made in view of such circumstances, and an object thereof is to provide a defect inspection system and a film manufacturing apparatus capable of suppressing a false alarm defect due to detection of a scratch.

In order to achieve the above object, the defect inspection system and the film manufacturing apparatus according to aspects of the present invention employ the following configurations.
(1) The defect inspection system which concerns on the 1st aspect of this invention is a defect inspection system of the strip | belt-shaped film which has a 1st film and the 2nd film laminated | stacked on the said 1st film so that peeling was possible. , A bonding roll for bonding the first film and the second film to form the film, a conveyance line for conveying the film on the downstream side of the bonding roll, and a conveyance line. A defect inspection apparatus, and a recording apparatus that is provided in the transport line downstream of the defect inspection apparatus and records defect information on defects detected by the defect inspection apparatus on the film, and the defect inspection An apparatus is arrange | positioned at the said conveyance line of an upstream rather than the roll which touches the surface on the opposite side to the said 1st film of the said 2nd film except the said bonding roll. That.

(2) In the defect inspection system according to (1), the defect inspection apparatus is disposed on the first film side of the film, and a light source that irradiates the film with light, and the second of the film. An imaging device that is disposed on the film side and captures a transmitted light image of the film; a first polarizing filter that is disposed on an optical path between the light source and the film and that has a first absorption axis; and the imaging A second polarizing filter disposed on an optical path between the device and the film and having a second absorption axis perpendicular to the first absorption axis.

(3) In the defect inspection system according to (1), the first film is a polarizer, and the defect inspection apparatus is disposed on the polarizer side of the film and irradiates the film with light. A light source, an imaging device disposed on the second film side of the film and capturing a transmitted light image of the film, and disposed on an optical path between the imaging device and the film, and absorbing the polarizer And a polarizing filter having an absorption axis orthogonal to the axis.

(4) A film manufacturing apparatus according to the second aspect of the present invention includes the defect inspection system according to any one of (1) to (3) above.

According to the aspect of the present invention, it is possible to provide a defect inspection system and a film manufacturing apparatus capable of suppressing a false alarm defect due to detection of a scratch.

It is a side view which shows the manufacturing apparatus of the film which concerns on 1st Embodiment. It is a figure for demonstrating the arrangement | positioning relationship between the 1st absorption axis of a 1st polarizing filter, and the 2nd absorption axis of a 2nd polarizing filter. 1 is a plan view of a defect inspection apparatus according to a first embodiment. It is a figure for demonstrating the defect inspection of the film by the defect inspection system which concerns on the comparative example 1. FIG. It is a figure for demonstrating the defect inspection of the film by the defect inspection system which concerns on 1st Embodiment. It is a side view which shows the manufacturing apparatus of the film which concerns on 2nd Embodiment. It is a figure for demonstrating the arrangement | positioning relationship between the absorption axis of a polarizer, and the absorption axis of a polarizing filter. It is a figure for demonstrating the defect inspection of the film by the defect inspection system which concerns on the comparative example 2. FIG. It is a figure for demonstrating the defect inspection of the film by the defect inspection system which concerns on 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments.

In all of the following drawings, the dimensions and ratios of the constituent elements are appropriately changed in order to make the drawings easy to see. In the following description and drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
FIG. 1 is a side view showing a film manufacturing apparatus 1 according to the first embodiment of the present invention. In FIG. 1, reference numeral Sf 1 is the upper surface of the film F, which is the surface on the first film F 1 side. Reference numeral Sf2 is a lower surface of the film F, which is a surface on the second film F2 side.

In the following description, an XYZ orthogonal coordinate system is set as necessary, and the positional relationship of each member will be described with reference to this XYZ orthogonal coordinate system. In the present embodiment, the transport direction of the belt-shaped film is the X direction, and the direction orthogonal to the X direction (the width direction of the long film) is orthogonal to the Y direction, the X direction, and the Y direction in the plane of the film. The direction is the Z direction.

As shown in FIG. 1, the film manufacturing apparatus 1 inspects the presence or absence of defects in the film F, the first supply unit 7 that supplies the first film F1, the second supply unit 8 that supplies the second film F2. The defect inspection system 2 to be performed, a plurality of rolls (for example, in the present embodiment, the first guide roll 10, the second guide roll 11, and the third guide roll 12) that form the transport path of the film F, and the film F are wound. A take-up unit 9 for taking up.

In the present embodiment, as the plurality of rolls forming the transport path of the film F, three guide rolls of the first guide roll 10, the second guide roll 11, and the third guide roll 12 are provided. Not limited to. For example, four or more guide rolls may be provided as a plurality of rolls forming the transport path of the film F, and a nip roll or a dancer roll may be provided in addition to the guide rolls. In addition to such contact rolls, non-contact rolls such as air bars may be provided.

The film F is a band-shaped film having a first film F1 and a second film F2 laminated on the first film F1 in a peelable manner. The film F used in the present embodiment has a structure in which, for example, one surface of the first film F1 that is a film used as a final product is covered with a second film F2 that is a separator film.

As the first film F1, for example, a film such as a TAC (Triacetylcellulose) film, a retardation film, a brightness enhancement film, and a viewing angle widening film is used. As the second film F2, for example, an adhesive film with a release film is used.
The film F may be a laminate of a plurality of optical films such as a retardation film and a brightness enhancement film on the other surface of the first film F1.

Further, when the second film F2 is peeled from the first film F1 in the film F, the entire second film F2 is not peeled from the first film F1. For example, a part (release film) of the second film F2 of the film F is peeled off, and the peeled film (first film F1 and adhesive material) is bonded to a panel or the like from the adhesive material side. . That is, after a part of the second film F2 is peeled off, the remaining part (adhesive material) of the second film F2 is disposed on one surface of the first film F1.

The 1st supply part 7 draws out the 1st film F1 along the longitudinal direction of the 1st film F1 while hold | maintaining the original fabric roll R1 which wound the strip | belt-shaped 1st film F1. The 1st supply part 7 is arrange | positioned at the one side (+ Z direction side shown in FIG. 1) of the supply path | route of the film F. As shown in FIG.

The second supply unit 8 holds the original roll R2 around which the belt-like second film F2 is wound, and feeds the second film F2 along the longitudinal direction of the second film F2. The second supply unit 8 is disposed on the other side (the −Z direction side shown in FIG. 1) of the supply path of the film F.

The arrangement configuration of the first supply unit 7 and the second supply unit 8 is not limited to this. For example, the first supply unit 7 is disposed on the other side of the supply path of the film F (the −Z direction side shown in FIG. 1), and the second supply unit 8 is disposed on one side of the supply path of the film F (see FIG. 1). (+ Z direction side shown).

In the defect inspection system 2, the film F is bonded on the downstream side of the bonding roll 3 and the bonding roll 3 in which two films of the first film F 1 and the second film F 2 are bonded to form one film F. A conveyance line 4 to be conveyed, a defect inspection device 5 provided in the conveyance line 4, and a recording device 6 provided in the conveyance line 4 on the downstream side of the defect inspection device 5 are provided.

The pasting roll 3 has a pair of nip rolls 3a and 3b that are arranged with their axial directions parallel to each other. A predetermined gap is formed between the pair of nip rolls 3a and 3b, and the inside of the gap is a bonding position between the first film F1 and the second film F2. The first film F1 and the second film F2 are overlapped and introduced into the gap. The first film F1 and the second film F2 are sent downstream while being pressed by the nip rolls 3a and 3b. Thereby, the 2nd film F2 is bonded by one side of the 1st film F1.

The 1st film F1 and the 2nd film F2 are bonded by the bonding roll 3, and the one film F is formed. The film F is conveyed toward the defect inspection apparatus 5.

The defect inspection apparatus 5 includes a light source 20 disposed on the first film F1 side of the film F (+ Z direction side shown in FIG. 1), and a second film F2 side of the film F (−Z direction side shown in FIG. 1). ), The first polarizing filter 21 arranged on the optical path between the light source 20 and the film F, and the second arranged on the optical path between the imaging apparatus 22 and the film F. And a polarizing filter 23.

The defect inspection apparatus 5 is arrange | positioned in the conveyance line 4 upstream from the roll which contact | connects the surface Sf2 on the opposite side to the 1st film F1 of the 2nd film F2 except the bonding roll 3. FIG. The defect inspection apparatus 5 according to the present embodiment is disposed on the transport line 4 on the downstream side of the bonding roll 3 and on the upstream side of the first guide roll 10. In this embodiment, the 1st guide roll 10 is a roll which contact | connects the surface Sf2 on the opposite side to the 1st film F1 of the 2nd film F2 other than the bonding roll 3 initially.

The center of the light exit surface 20a of the light source 20 and the center of the light receiving surface 22a of the imaging device 22 are arranged coaxially (on the optical axis CL).

FIG. 2 is a diagram for explaining the positional relationship between the first absorption axis V1 of the first polarizing filter 21 and the second absorption axis V2 of the second polarizing filter 23. FIG.

As shown in FIG. 2, the first polarizing filter 21 has a first absorption axis V1. The second polarizing filter 23 has a second absorption axis V2 that is orthogonal to the first absorption axis V1. In the first polarizing filter 21, the first absorption axis V 1 of the first polarizing filter 21 and the second absorption axis V 2 of the second polarizing filter 23 are orthogonal to each other on the optical path between the light source 20 and the imaging device 22. Is arranged (crossed Nicols arrangement).

In the case of the present embodiment, the film F (see FIG. 1) is a film that does not give a phase difference to the light transmitted through the first polarizing filter 21. Therefore, when the first absorption axis V1 of the first polarizing filter 21 and the second absorption axis V2 of the second polarizing filter 23 are arranged in a crossed Nicols arrangement, the overlapping portion of the first polarizing filter 21 and the second polarizing filter 23 In SV, light is not transmitted. Therefore, when the overlapping portion SV is imaged by the imaging device 22, the dark field is not displayed unless anything that disturbs the polarization state such as a defect having a phase difference is disposed between the first polarizing filter 21 and the second polarizing filter 23. appear.

When the film F is a film that gives a phase difference to the light transmitted through the first polarizing filter 21, a phase compensation film that cancels the phase difference is used as the first polarizing filter 21 and the second polarizing filter 21. You may arrange | position between the polarizing filters 23. When the phase compensation film is not arranged, the transmission axis of the first polarizing filter 21 and the transmission axis of the second polarizing filter 23 are arranged at an angle deviated from 90 ° by a predetermined angle, and there is no defect such as a foreign substance defect. The received light intensity in the imaging device 22 may be minimized (dark field).

FIG. 3 is a plan view of the defect inspection apparatus 5. In FIG. 3, the film F is shown for convenience.

As shown in FIG. 3, the light emission surface 20a of the light source 20 constituting the defect inspection apparatus 5 is a rectangle and has a length along the Y direction. In the present embodiment, the light exit surface 20 a of the light source 20 has a length along the width direction orthogonal to the transport direction of the film F. The light emission surface 20 a of the light source 20 is formed across the width direction with respect to the film F. For example, an LED line light source can be used as the light source 20.

The first polarizing filter 21 is disposed so as to overlap the outer peripheral portion of the light exit surface 20a of the light source 20. The first polarizing filter 21 has a length along the Y direction, similarly to the light exit surface 20 a of the light source 20. The first polarizing filter 21 is longer than the light exit surface 20a of the light source 20 in each of the X direction and the Y direction.

Thereby, when the first polarizing filter 21 is disposed on the optical path between the light source 20 and the film F, all the light emitted from the light source 20 enters the first polarizing filter 21.

The imaging device 22 also has a longitudinal direction along the Y direction, similarly to the light exit surface 20a of the light source 20. For example, a line camera can be used as the imaging device 22.

The second polarizing filter 23 is disposed so as to overlap with the outer periphery of the light receiving surface 22a of the imaging device 22. Similar to the light receiving surface 22a of the imaging device 22, the second polarizing filter 23 has a length along the Y direction. The second polarizing filter 23 is longer than the light receiving surface 22a of the imaging device 22 in each of the X direction and the Y direction.

Returning to FIG. 1, the recording device 6 is provided in the transport line 4 on the downstream side of the third guide roll 12. The recording device 6 records defect information related to the defect detected by the defect inspection device 5 on the film F (for example, the first film F1 in the present embodiment). The defect information includes information on the position and type of the defect.

The recording device 6 records, for example, defect information in the width direction end of the first film F1 in the form of an identification code (one-dimensional barcode, two-dimensional barcode, QR code (registered trademark), etc.). In the identification code, for example, information indicating how far the defect detected by the defect inspection apparatus 5 exists at a position along the film width direction from the position where the barcode is attached (defects). Location information). The identification code may include information regarding the type of detected defect.

The recording device 6 directly displays the position of the defect on the first film F1 by attaching a dot-shaped, line-shaped or frame-shaped mark that includes the defect to the defective portion of the first film F1. (Marking) may be used. At this time, information on the type of defect may be recorded by attaching a symbol or pattern indicating the type of defect together with the mark to the defective part.

The film F on which the defect information is recorded by the recording device 6 is conveyed toward the winding unit 9. And it winds up in roll shape in the winding-up part 9, and the roll original fabric R of the film F is manufactured.

Incidentally, the defect inspection apparatus is usually provided on the downstream side of the transport line. This is because if the defect inspection apparatus is provided on the downstream side of the conveyance line rather than the upstream side of the conveyance line, defects such as scratches generated on the film during conveyance can be collectively inspected. For example, the defect inspection apparatus inspects the film for defects after contacting the rolls of 10 to 20.

Therefore, one embodiment of the present invention employs the following configuration in order to solve such a problem.
The defect inspection system 2 according to the first embodiment of the present invention is a defect inspection system for a strip-shaped film F having a first film F1 and a second film F2 that is detachably laminated on the first film F1. And the 1st film F1 and the 2nd film F2 are bonded, the bonding roll 3 which forms the film F, the conveyance line 4 in which the film F is conveyed in the downstream of the bonding roll 3, and the conveyance line 4 A defect inspection apparatus 5 provided on the recording line, and a recording apparatus 6 provided on the transport line 4 on the downstream side of the defect inspection apparatus 5 for recording defect information relating to defects detected by the defect inspection apparatus 5 on the film F. In addition, the defect inspection apparatus 5 other than the bonding roll 3 is upstream of the roll (first guide roll 10) that first contacts the surface Sf2 opposite to the first film F1 of the second film F2. Characterized in that it is arranged to feed lines 4.
In other words, the defect inspection system 2 according to the first embodiment of the present invention is a defect of the strip-shaped film F having the first film F1 and the second film F2 that is detachably laminated on the first film F1. It is a test | inspection system, Comprising: The laminating roll 3 which bonds the 1st film F1 and the 2nd film F2 and forms the film F, The conveyance line 4 with which the film F is conveyed in the downstream of the laminating roll 3, and , A defect inspection apparatus 5 provided on the conveyance line 4, and a recording apparatus which is provided in the conveyance line 4 downstream of the defect inspection apparatus 5 and records defect information relating to defects detected by the defect inspection apparatus 5 on the film F. 6 and a plurality of rolls (first guide roll 10, second guide roll 11, third guide roll 12) provided in the transport line 4, and the defect inspection apparatus 5 includes a plurality of rolls. Among them, they are arranged in the conveying line 4 upstream of the roll (the first guide roll 10) in contact with the first opposite surface Sf2 the first film F1 of the second film F2.

Hereinafter, the operational effects of the defect inspection system 2 according to the present embodiment will be described with reference to FIGS. 4 and 5.

FIG. 4 is a diagram for explaining defect inspection of the film F by the defect inspection system according to Comparative Example 1.
In the defect inspection system according to Comparative Example 1, the defect inspection apparatus 5 is a roll that is in contact with the surface Sf2 on the opposite side of the first film F1 of the second film F2 other than the bonding roll 3 (for example, a plurality of guide rolls). Of these, it is disposed on the transport line 4 on the downstream side of the guide roll that comes into contact with the surface Sf2 last. FIG. 4 shows that a defect E1 is present in the film F due to entrapment of bubbles or the like when the first film F1 and the second film F2 are bonded together, and the second film F2 is being conveyed. It is a figure in case the crack E2 has arisen on the surface of the 2nd film F2 by the friction with a guide roll.

4, the light L1 emitted from the light source 20 toward the film F is converted into linearly polarized light L2 by the first polarizing filter 21. The linearly polarized light L2 obtained by the first polarizing filter 21 is incident on the first film F1. Then, the polarization state of the linearly polarized light L2 is disturbed by the defect E1 existing between the first film F1 and the second film F2, and a part of the light (light L3) whose polarization state is disturbed is the second polarizing filter 23. Transparent.

On the other hand, the polarization state of the linearly polarized light L2 is also disturbed by the scratch E2 present on the surface of the second film F2, and a part of the light whose polarization state is disturbed (light L4) passes through the second polarizing filter 23.

As a result, the light L3 and the light L4 that have passed through the second polarizing filter 23 enter the imaging device 22, and the imaging device 22 captures bright images of the defect E1 and the scratch E2 as bright spots.

In addition, even if there is no defect E1 between the first film F1 and the second film F2, if there is a scratch E2 on the surface of the second film F2, the light L4 transmitted through the second polarizing filter 23 Is incident on the image pickup device 22 and the image pickup device 22 picks up the flaw E2 brightly as a bright spot.

Thus, in Comparative Example 1, when scratch E2 is generated on the surface of the second film F2 due to friction with the guide roll during the conveyance of the film F, the second film F2 is removed from the first film F1 in the final product. When the film is peeled off, a scratch on the surface of the second film F2 that does not originally become a problem is erroneously detected as a defect.

FIG. 5 is a view for explaining defect inspection of the film F by the defect inspection system 2 according to the present embodiment.
In the defect inspection system 2 according to the present embodiment, the defect inspection device 5 is a roll that first contacts the surface Sf2 opposite to the first film F1 of the second film F2 other than the bonding roll 3 (for example, the present embodiment). In the form, it is arranged in the transport line 4 upstream of the first guide roll 10). FIG. 5 is a diagram in the case where a defect E1 is present in the film F due to entrapment of bubbles or the like when the first film F1 and the second film F2 are bonded. In addition, since the defect of the film F is inspected before the second film F2 is scratched, the surface of the second film F2 is not scratched.

As shown in FIG. 5, the light L 1 emitted from the light source 20 toward the film F is converted into linearly polarized light L 2 by the first polarizing filter 21. The linearly polarized light L2 obtained by the first polarizing filter 21 is incident on the first film F1. Then, the polarization state of the linearly polarized light L2 is disturbed by the defect E1 existing between the first film F1 and the second film F2, and a part of the light (light L3) whose polarization state is disturbed is the second polarizing filter 23. Transparent. As a result, the light L3 transmitted through the second polarizing filter 23 enters the image pickup device 22, and the image pickup device 22 picks up the defect E1 brightly as a bright spot.

On the other hand, when there is no defect E1 between the first film F1 and the second film F2, the linearly polarized light L2 cannot pass through the second polarizing filter 23. As a result, since no light is incident on the imaging device 22, the imaging device 22 captures a black image.

Thus, in this embodiment, since the surface of the second film F2 is not scratched, the surface of the second film F2 is not erroneously detected as a defect.

As described above, according to the present embodiment, the defect inspection device 5 is a roll that first contacts the surface Sf2 opposite to the first film F1 of the second film F2 other than the bonding roll 3 (for example, a book) In the embodiment, the film F is inspected for defects before being scratched on the second film F2 because it is disposed on the transport line 4 upstream of the first guide roll 10). That is, since the friction between the second film F2 and the guide roll does not occur during the conveyance of the film F, the surface of the second film F2 is not scratched. Therefore, it is possible to suppress the false alarm defect (defect detection as the false alarm) due to the detection of the scratch.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS.
FIG. 6 is a side view showing a film manufacturing apparatus 101 according to the second embodiment of the present invention.
As shown in FIG. 6, in the film manufacturing apparatus 101 according to this embodiment, the first film F 1 a is a polarizer, and the defect inspection apparatus 105 includes a light source 20 disposed on the polarizer F 1 a side of the film Fa. First, in that the image pickup device 22 disposed on the second film F2 side of the film Fa and the polarizing filter 123 disposed on the optical path between the image pickup device 22 and the film Fa are provided. Different from the film manufacturing apparatus 1 according to the embodiment. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

The film Fa is a belt-like film having a polarizer F1a and a second film F2 laminated on the polarizer F1a so as to be peelable. The film F used in this embodiment has a structure in which, for example, one surface of a polarizer F1a made of PVA (polyvinyl alcohol) or the like is covered with a second film F2 that is a separator film.

In addition, the film Fa may be obtained by laminating a plurality of optical films such as a retardation film and a brightness enhancement film on the other surface of the polarizer F1a.

In the case of the present embodiment, the film Fa is a film that does not give a phase difference to the light transmitted through the polarizer F1a, but the film Fa gives a phase difference to the light transmitted through the polarizer F1a. In the case of a film to be used, a phase compensation film that cancels out the phase difference may be disposed between the film Fa and the polarizing filter 123. When the phase compensation film is not disposed, the imaging device 22 is disposed in a state where the transmission axis of the polarizer F1a and the transmission axis of the polarizing filter 123 are shifted by a predetermined angle from 90 ° and there is no defect such as a foreign object defect. The received light intensity at may be minimized (dark field).

The defect inspection apparatus 105 is arrange | positioned in the conveyance line 4 upstream from the roll which contact | connects the surface Sf2 on the opposite side to the polarizer F1a of the 2nd film F2 except the bonding roll 3. FIG. The defect inspection apparatus 105 according to this embodiment is disposed on the conveyance line 4 on the downstream side of the bonding roll 3 and on the upstream side of the first guide roll 10.

FIG. 7 is a diagram for explaining the positional relationship between the absorption axis Va of the polarizer F1a and the absorption axis V of the polarizing filter 123. FIG.

As shown in FIG. 7, the polarizer F1a has an absorption axis Va. The polarizing filter 123 has an absorption axis V orthogonal to the absorption axis Va. In the polarizing filter 123, the absorption axis Va of the polarizer F1a and the absorption axis V of the polarizing filter 123 are arranged orthogonal to each other (crossed Nicols arrangement) on the optical path between the light source 20 and the imaging device 22.

When the absorption axis Va of the polarizer F1a and the absorption axis V of the polarizing filter 123 are arranged in a crossed Nicol arrangement, light does not pass through the overlapping portion SV between the polarizer F1a and the polarizing filter 123. Therefore, when the overlapping portion SV is imaged by the imaging device 22, it appears as a dark field unless an object that disturbs the polarization state such as a defect having a phase difference is disposed between the polarizer F1a and the polarizing filter 123.

Hereinafter, the operational effects of the defect inspection system 102 according to the present embodiment will be described with reference to FIGS. 8 and 9.

FIG. 8 is a diagram for explaining defect inspection of the film Fa by the defect inspection system according to the comparative example 2.
In the defect inspection system according to Comparative Example 2, the defect inspection apparatus 105 is a roll that is in contact with the surface Sf2 opposite to the polarizer F1a of the second film F2 other than the bonding roll 3 (for example, among a plurality of guide rolls) It is disposed on the transport line 4 on the downstream side of the guide roll that comes into contact with the surface Sf2 last. FIG. 8 shows that a defect E1 is present in the film Fa due to entrapment of bubbles or the like when the polarizer F1a and the second film F2 are bonded together, and the second film F2 is being transported while the film Fa is being conveyed. It is a figure in case the crack E2 has arisen on the surface of the 2nd film F2 by friction with a guide roll.

As shown in FIG. 8, the light L1 emitted from the light source 20 toward the film Fa is converted into linearly polarized light L2 by the polarizer F1a. The linearly polarized light L2 obtained by the polarizer F1a is incident on the second film F2. Then, the polarization state of the linearly polarized light L2 is disturbed by the defect E1 existing between the polarizer F1a and the second film F2, and a part of the light whose polarization state is disturbed (light L3) passes through the polarizing filter 123. .

On the other hand, the polarization state of the linearly polarized light L2 is also disturbed by the scratch E2 existing on the surface of the second film F2, and a part of the light (light L4) whose polarization state is disturbed is transmitted through the polarizing filter 123.

As a result, the light L3 and the light L4 that have been transmitted through the polarizing filter 123 enter the imaging device 22, and the defect E1 and the scratch E2 are brightly imaged as bright spots by the imaging device 22.

In addition, even if there is no defect E1 between the polarizer F1a and the second film F2, if there is a scratch E2 on the surface of the second film F2, the light L4 transmitted through the polarizing filter 123 is captured by the imaging device. 22 and the image pick-up device 22 picks up the flaw E2 brightly as a bright spot.

As described above, in Comparative Example 2, when scratches E2 are generated on the surface of the second film F2 due to friction with the guide roll during conveyance of the film Fa, the second film F2 is peeled from the polarizer F1a in the final product. In such a case, a scratch on the surface of the second film F2 that does not originally become a problem is erroneously detected as a defect.

FIG. 9 is a view for explaining defect inspection of the film Fa by the defect inspection system 102 according to the present embodiment.
In the defect inspection system 102 according to the present embodiment, the defect inspection apparatus 105 is a roll that first contacts the surface Sf2 opposite to the polarizer F1a of the second film F2 other than the bonding roll 3 (for example, the present embodiment). Then, it is arrange | positioned in the conveyance line 4 upstream from the 1st guide roll 10). FIG. 9 is a diagram in the case where a defect E1 is present in the film Fa due to the entrapment of bubbles or the like when the polarizer F1a and the second film F2 are bonded. In addition, since the defect of the film Fa is inspected before the second film F2 is scratched, the surface of the second film F2 is not scratched.

As shown in FIG. 9, the light L1 emitted from the light source 20 toward the film Fa is converted into linearly polarized light L2 by the polarizer F1a. The linearly polarized light L2 obtained by the polarizer F1a is incident on the second film F2. Then, the polarization state of the linearly polarized light L2 is disturbed by the defect E1 existing between the polarizer F1a and the second film F2, and a part of the light whose polarization state is disturbed (light L3) passes through the polarizing filter 123. .

As a result, the light L3 that has passed through the polarizing filter 123 enters the image pickup device 22, and the image pickup device 22 picks up the defect E1 brightly as a bright spot.

On the other hand, when there is no defect E1 between the polarizer F1a and the second film F2, the linearly polarized light L2 cannot pass through the polarizing filter 123. As a result, since no light is incident on the imaging device 22, the imaging device 22 captures a black image.

As described above, according to the present embodiment, the defect inspection apparatus 105 is a roll that first contacts the surface Sf2 opposite to the polarizer F1a of the second film F2 other than the bonding roll 3 (for example, the present embodiment). In the embodiment, the film Fa is disposed on the transport line 4 upstream of the first guide roll 10), so the film Fa is inspected for defects before the second film F2 is scratched. That is, since the friction between the second film F2 and the guide roll does not occur during the conveyance of the film Fa, the surface of the second film F2 is not scratched. Accordingly, it is possible to suppress false alarm defects due to detection of scratches.

As described above, the preferred embodiment according to the present embodiment has been described with reference to the accompanying drawings, but the present invention is not limited to the example. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Film manufacturing apparatus, 2,102 ... Defect inspection system, 3 ... Bonding roll, 4 ... Conveyance line, 5,105 ... Defect inspection apparatus, 6 ... Recording apparatus, 10 ... 1st guide roll (of 2nd film) First roll in contact with the surface opposite to the first film), 20 ... light source, 21 ... first polarizing filter, 22 ... imaging device, 23 ... second polarizing filter, 123 ... polarizing filter, F ... film, F1 ... First film, F1a: Polarizer, F2: Second film, Sf2: Surface of the second film opposite to the first film, V1: First absorption axis, V2: Second absorption axis, Va: Polarized light Absorption axis of child, V: Absorption axis of polarizing filter.

Claims

A strip-shaped film defect inspection system having a first film and a second film peelably laminated on the first film,
A laminating roll for laminating the first film and the second film to form the film;
A transport line on which the film is transported on the downstream side of the bonding roll;
A defect inspection apparatus provided in the transfer line;
A recording device that is provided in the transport line downstream of the defect inspection device and records defect information on the defect detected by the defect inspection device on the film;
The said defect inspection apparatus is a defect inspection system arrange | positioned in the said conveyance line upstream from the roll which touches the surface on the opposite side to the said 1st film of the said 2nd film except the said bonding roll.
The defect inspection apparatus includes:
A light source disposed on the first film side of the film and irradiating the film with light;
An imaging device that is disposed on the second film side of the film and captures a transmitted light image of the film;
A first polarizing filter disposed on an optical path between the light source and the film and having a first absorption axis;
A second polarizing filter disposed on an optical path between the imaging device and the film and having a second absorption axis perpendicular to the first absorption axis;
The defect inspection system according to claim 1, comprising:
The first film is a polarizer;
The defect inspection apparatus includes:
A light source disposed on the polarizer side of the film and irradiating the film with light;
An imaging device that is disposed on the second film side of the film and captures a transmitted light image of the film;
A polarizing filter disposed on an optical path between the imaging device and the film and having an absorption axis perpendicular to the absorption axis of the polarizer;
The defect inspection system according to claim 1, comprising:
A film manufacturing apparatus including the defect inspection system according to any one of claims 1 to 3.