KR101311496B1 - Apparatus for inspecting faulty of optical film - Google Patents

Abstract

The present invention relates to a defect inspection apparatus for an optical film, comprising: an illumination unit capable of irradiating light onto an optical film; A first filter unit disposed between the optical film and the illumination unit; A photographing unit installed to face the illumination unit so as to photograph the optical film; And a second filter unit disposed between the optical film and the photographing unit.

Description

Apparatus for inspecting faulty of optical film

preference

The present invention enjoys the priority of the 'fail inspection apparatus for FPR film' of Korean Patent Application No. 10-2011-0107642 filed on Oct. 20, 2011, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defect inspection apparatus of an optical film, and more particularly, to inspect an optical defect (eg, 3D defect) due to a phase change of an optical film such as an FPR film used in a 3D display device. It is about a device.

Generally, it is known that human being feels three dimensional feeling because the right eye and the left eye perceive objects with time lag. That is, since the human eyes are spaced apart at a distance of about 65 cm, a person perceives a three-dimensional effect by binocular disparity generated while viewing images in slightly different directions.

Recently, interest in stereoscopic image display systems capable of realizing stereoscopic images by inputting images with parallax in both eyes has been increasing.

In general, stereoscopic image display devices are spectacle type such as shutter glasses, micro polarizer, patterned retarder, glasses type 3D display, parallax barrier, lenticular lens, etc. 3D display, and holographic 3D display. Of these, stereoscopic image display devices have become popular as active systems (shutter glass systems) and passive systems (FPR systems).

In the active mode, the display alternately transmits the screen corresponding to the left and right at a very high speed, and accordingly, the stereoscopic glasses worn by the user are linked to the transmitted image and operate together. That is, the active method is a so-called 'time division method'. In the case of the left eye image, the right eye lens is closed when the left eye lens is opened, whereas the right eye image is a structure in which the left eye lens is closed when the right eye lens is opened. This approach has the advantage of being able to see the screen clearly, but it requires a high level of skill to synchronize the movement of the display with the glasses.

The passive method is a so-called "spatial partitioning method", and is capable of transmitting a left eye image and a right eye image having different polarization characteristics, and includes a display having a polarizing filter attached to the front and polarizing glasses worn by a user. Only the left eye image transmitted from the display is viewed through the left eye lens of the polarizing glasses and only the right eye image is viewed through the right eye lens of the polarizing glasses. This pass method is easy to implement without technical difficulties.

However, the polarizing filter used in the passive system can be attached to the polarizing plate so that the polarizing plate itself is patterned so as to correspond to the left and right eye image display units, or the polarizing plates are respectively associated with the left and right eye image display units Called Pattern-type Patterned Retarder (FPR), such as a patterned retardation plate (optical filter) having a patterned pattern.

In addition, patterned retarders are classified into glass-type and film-type depending on the type of substrate. However, since glass-type patterned lather is difficult to meet the trend of large-sized display, a patterned retarder film using an organic polymer film as a substrate has become popular in recent years.

However, the size of a pattern formed in the patterned retarder corresponds to the width of a pixel or a pixel and is very precise, and the shape of the pattern is generally formed in accordance with the row or column of the LCD. When the pattern is formed on the LCD, It is necessary to suppress the generation of dimensional defects in the manufacturing process of the patterned retarder and it is necessary to control the phase due to the damage of the liquid crystal layer and the culture layer of the patterned retarder There is a need to strictly control the defects due to the change (irrelevant to the defect of the display panel for 2D).

In addition, according to the conventional manufacturing method, the finished patterned retarder is delivered to the display panel manufacturer by attaching a protective film for reasons such as transportation failure, and the delivered patterned retarder is, for example, before it is finally attached to the panel. Because of using a so-called 'full line' inspection method in which two polarizers are visually inspected by crossing two polarizers, a defect rate is very high. Accordingly, there is a demand for the development of a system for inspecting defects due to phase change in the production line of the patterned retarder film.

The present invention has been conceived to solve the problems described above, the production process of the product to ensure the quality of the product together with the mass production of the 3D film, that is, the product in the in-line (IN-LINE) before the optical film is wound on the winder An object of the present invention is to provide a defect inspection apparatus of an optical film capable of inspecting 3D defects.

According to another aspect, the present invention is an apparatus for defect inspection of an optical film that can change the type of filter appropriately for such a panel in the system even if the optical films having optical properties that can be attached to the IPS panel or the TN panel, respectively, are changed. The purpose is to provide.

In order to solve the above problems, a defect inspection apparatus of an optical film according to an exemplary embodiment of the present invention, an illumination unit capable of irradiating light to the optical film; A first filter unit disposed between the optical film and the illumination unit; A photographing unit provided to face the illumination unit so as to photograph the optical film; And a second filter unit disposed between the optical film and the photographing unit and including at least one or more filters.

Preferably, the optical film is a pattern relief film (FPR) in which L and R patterns having different optical axes are formed.

Preferably, the FPR is in an in-line state before the substrate on which the alignment layer and the liquid crystal layer are formed is wound on the winder in the traveling direction.

Preferably, the optical film travels at a predetermined speed; The photographing unit is one or more for photographing a predetermined area in the width direction of the optical film represented by a value combined by the first and second filter units in a state where light is irradiated through the illumination unit. With cameras.

Preferably, the cameras include: an odd camera group including a plurality of odd cameras spaced apart from each other at a first predetermined interval in a width direction of the optical film; And focus at centers of the first intervals so as to photograph a width portion of the optical film that is spaced apart from the odd camera group by a predetermined interval in the advancing direction of the optical film and not photographed by the odd cameras. And an even camera group comprising a plurality of even cameras spaced apart from each other at a second predetermined interval.

Preferably, the illumination unit may irradiate light over the entire width direction of the optical film.

Preferably, the lighting unit comprises: a plurality of LED lights installed in the lighting frame; And a light guide plate capable of converting light emitted from the LED lights into a surface light source and irradiating the optical film.

Preferably, the first filter unit comprises a polarizing filter.

Preferably, the polarizing filter has a single elongated filter sheet disposed long in the width direction of the optical film.

Preferably, the first filter unit selectively selects first and second polarization filters having different characteristics with optimal angles corresponding to optical characteristics of the optical film on a focal line formed by the illumination unit and the photographing unit. It is provided with a filter feed member that can be positioned.

Preferably, the filter transfer member comprises: a first through slit and a second through slit which are arranged to be spaced apart from the optical film by a predetermined interval so as to be parallel to the optical film and through which light of the lighting unit can be transmitted, respectively; 1 filter bracket; A first filter sheet and a second filter sheet respectively provided in the first through slit and the second through slit; And a guide part provided between the first filter bracket and the first filter frame to selectively move the first filter bracket.

Preferably, the first filter unit is divided into an odd first filter unit corresponding to the odd camera group and an even first filter unit corresponding to the even camera group.

Preferably, the second filter unit has a circular polarization filter for separating the L and R patterns of the optical film and for controlling scattering of light.

Preferably, the circular polarizing filter includes a filter module assembled in a circle.

Preferably, the filter module is integrally disposed at the end of the photographing unit.

Preferably, the photographing unit has a plurality of cameras; The filter module is fixedly installed at the lens end of each camera.

Preferably, the apparatus further includes a marking unit capable of marking the presence or absence of a defect on the surface of the optical film that travels to correspond to the positional information of the defect shown in the image photographed by the photographing unit.

Preferably, the control unit for calculating and storing the position information of the defect displayed on the images taken by the imaging unit; And a display unit capable of displaying the respective images.

The inspection apparatus according to a preferred exemplary embodiment of the present invention can detect a defect before the optical film is wound on the winder in the production line of the optical film produced in the order of substrate => alignment film => liquid crystal => release film. In the film region determined to be defective, a defective indication mark may be printed.

In the defect inspection apparatus of an optical film according to a preferred exemplary embodiment of the present invention, the illumination side PL filter is a kind of optical film to be inspected, such as an optical film to be attached to an IPS panel, an optical film to be attached to a TN panel. It is configured to selectively use a filter having an optical characteristic corresponding to.

The defect inspection apparatus of the optical film which concerns on this invention has the following effects.

First, selectively changing a polarizing filter sheet having optical properties corresponding to the optical properties of the optical film to be inspected whenever the type of optical film to be inspected changes, such as an optical film to be used for an IPS panel or an optical film to be used for a TN panel. In this way, the production cost can be reduced by avoiding the overlapping investment of separate inspection systems according to the type of optical film (that is, the polarization filter is one combination so as to correspond to the optical film for IPS panel or the optical film for TN panel, respectively. Exists).

Second, since a relatively sharp image can be realized, for example, if a liquid crystal is damaged in a dot form within the white pattern of the FPR, the damaged dot is inverted to appear as a black dot, and conversely, a black dot to appear as a white dot. The defect which a phase change generate | occur | produces by damaging a liquid crystal layer and an orientation layer in the manufacturing process of an optical film, such as a bright point defect, a dark point defect, a scratch defect, etc. which can be made can be examined.

Third, since the film can be inspected for defects before being wound on the winder in the production process of the FPR film, pre-determination can be performed according to the inspection type, thereby increasing production efficiency and reducing production cost.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be described in detail with reference to the following drawings, which illustrate preferred embodiments of the present invention, and thus the technical idea of the present invention should not be construed as being limited thereto.
1 is a conceptual diagram schematically showing a main configuration of a defect inspection apparatus of an optical film according to a preferred exemplary embodiment of the present invention.
Fig. 2 is a schematic diagram showing the configuration of a defect inspection apparatus for an optical film according to another exemplary embodiment of the present invention.
FIG. 3 is a plan view of FIG. 2 schematically showing main components of a defect inspection apparatus of an optical film according to another preferred exemplary embodiment of the present invention.
4 is an enlarged view of the lighting unit part shown in FIGS. 2 and 3.
FIG. 5 is a right side view of FIG. 2 showing an excerpt of the lighting unit. FIG.
6 is a right side view of FIGS. 2 and 3 showing an excerpt of the first filter unit portion.
7 is a conceptual view for explaining the operation of the first filter unit by the filter feed member of the defect inspection apparatus of the optical film according to an exemplary embodiment of the present invention.
8 is an enlarged view of a portion of a second filter unit together with the photographing unit shown in FIG. 2.
9 is an enlarged view of a portion of the marking unit shown in FIG. 2.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

1 is a conceptual diagram schematically showing a main configuration of a defect inspection apparatus of an optical film according to a preferred exemplary embodiment of the present invention.

Referring to FIG. 1, a defect inspection apparatus 1 of an optical film according to an exemplary embodiment of the present invention is for inspecting a defect of an optical film 10, and may irradiate light onto the optical film 10. An illumination unit 20, a first filter unit 30 disposed between the optical film 10 and the illumination unit 20, and a photographing unit installed to face the illumination unit 20 so as to photograph the optical film 10. 40, and a second filter unit 50 disposed between the optical film 10 and the imaging unit 40 and including a circularly polarized light filter 54.

The optical film 10 is a patterned retard film (FPR) in which L and R patterns having different optical axes are formed. In the optical film 10 of the FPR type, an alignment layer 16 and a liquid crystal layer 18 are formed on the surface of the substrate 14. As will be described later, the patterned retard film or optical film 10 is preferably in an in-line state before being wound on a winder (not shown) while the film is traveling. In an alternative embodiment, those skilled in the art will fully appreciate that the defect inspection apparatus 1 of the optical film may be applied to the finished patterned retarder film or the optical filter cut such film to a predetermined size.

The base material 14 of the optical film 10 is made of, for example, a cycloolefin polymer such as triacetylcellulose, polyacrylate, polyethylene terephthalate, polycarbonate, polyethylene, norbornene derivatives and the like. It is preferable that the base material 14 is an isotropic base material having almost no in-plane retardation and thickness retardation or only a retardation value in the thickness direction without in-plane retardation. On the other hand, the width of the optical film 10 is substantially determined by the width of the substrate 14, and can be variously configured with a width of, for example, 1200 mm to 2200 mm.

The orientation layer 16 of the optical film 10 has an alignment treatment method and an alignment direction in which the first alignment film and the second alignment film are different from each other. For example, if the first alignment layer is a photo alignment layer, the second alignment layer is a rubbing alignment layer, and if the first alignment layer is a rubbing alignment layer, the second alignment layer is a photo alignment layer. When an alignment film having a different processing method is used, since one alignment film processing method does not affect other alignment films, an alignment film having different alignment directions can be easily formed without going through a complicated process such as a mask or a photoresist. For example, even if the rubbing alignment film is irradiated with UV polarized light, the alignment direction of the alignment film is not changed, and the case where the rubbing process is performed on the photo alignment film is also reversed. Therefore, after the rubbing alignment film is applied, the rubbing process is performed in the first alignment direction to form the rubbing alignment film, the polymer film for the photo alignment film is coated thereon at regular intervals thereon, and the polarized film is polarized in the second alignment direction different from the first alignment direction By the method of irradiating UV polarized light, the first alignment film and the second alignment film having different alignment directions can be formed. It is preferable that the alignment directions of the first alignment film and the second alignment film are perpendicular to each other.

The liquid crystal layer 18 of the optical film 10 is formed on the first alignment film and the second alignment film and is patterned into a first region oriented by the first alignment film and a second region oriented by the second alignment film. When the liquid crystal material is applied on the alignment layer, the liquid crystal material is oriented along the alignment direction of the alignment layer. Since the first alignment layer and the second alignment layer have different alignment directions, the liquid crystal layer 18 formed thereon is also oriented The liquid crystal layer 18 is alternately formed, and as a result, a patterned retardation layer can be formed. The pattern of the liquid crystal layer 18 is determined according to the application pattern of the second alignment film. For example, when the second alignment film is in a stripe shape, a liquid crystal layer of a stripe pattern is formed, and when the second alignment film is applied in a checkerboard pattern, a checkerboard pattern liquid crystal layer is formed.

On the other hand, the liquid crystal layer 18 may have various retardations depending on its thickness, and may preferably be a quarter-wave retardation layer. When the liquid crystal layer 18 is a quarter-wave retardation layer, the polarized light is converted into circularly polarized light when the incident light source is linearly polarized light and linearly polarized light when the incident light source is circularly polarized light. This is because it is useful for stereoscopic image display.

Referring again to FIG. 1, the illumination unit 20 is for irradiating light in the direction of the optical film 10 to provide the light necessary for the photographing unit 40 to photograph the surface of the optical film 10. For example, use LED lighting. Of course, those skilled in the art will understand that the lighting unit 20 may use illumination, such as fluorescent, incandescent or the like, for the LED illumination.

The first filter unit 30 is disposed between the optical film 10 and the illumination unit 20, and can perform a polarizing function at a specific angle corresponding to the type of optical film 10 to be inspected. (Polarization) filter. That is, the first filter unit 30 may be, for example, depending on the case where the optical film 10 is an FPR used for an In-Plane Swithcing (IPS) panel and an FPR used for a twisted nematic (TN) panel. Other specific angle PL filters can be used. The first filter unit 30 has a function of limiting saturation of light according to the phase change of the optical film 10.

The photographing unit 40 compensates for the light irradiated from the illumination unit 20 by the first filter unit 30 through the optical axis of the polarization axis of the optical film 10 and the second filter unit 50. For photographing the surface of the optical film 10 optimized by polarized light, it includes a camera 42.

The second filter unit 50 includes a CPL (circular polarized light) filter 54 disposed between the optical film 10 and the imaging unit 40. The CPL filter 54 separates the L pattern (left eye pattern) and the R pattern (right eye pattern) of the optical film 10 and controls light scattering. In addition, the circularly polarized filter 54 of the second filter unit 50 may have a modular structure, as described later. In addition, as will be described later, it is preferable that the second filter unit 50 is integrally fixed to the tip of the camera 42 of the imaging unit 40.

2 is a schematic view showing the configuration of a defect inspection apparatus for an optical film according to another preferred exemplary embodiment of the present invention, Figure 3 is a defect inspection of an optical film according to another preferred exemplary embodiment of the present invention 2 is a plan view of FIG. 2 schematically showing the main components of the apparatus. The same components as those described in FIG. 1 are the same members with the same functions.

2 and 3, the defect inspection apparatus 100 of the optical film according to the present embodiment is similar to the above-described embodiment, and the alignment layer 16 and the liquid crystal layer 18 on one surface of the substrate 14. Is formed to produce an optical film 10 such as FPR, that is, 3D due to the phase change of the optical film 10 in the IN-Line state before the optical film 10 is wound on the winder (not shown). To check for defects. Therefore, the defective data inspected by the apparatus 100 can be confirmed in real time, and the necessary measures can be taken immediately.

The defect inspection apparatus 100 of the optical film according to the present embodiment includes an illumination unit for irradiating light to the optical film 10 traveling at a predetermined speed along a plurality of rollers 104 installed in the main frame 102 ( 120, a predetermined region in the width direction of the optical film 10 in a state where light is irradiated through the first filter unit 130 and the lighting unit 120 provided between the lighting unit 120 and the optical film 10. A second filter unit including a photographing unit 140 having a plurality of cameras 142 for photographing the photographs, and a circularly biased filter 154 respectively installed at the tip of each camera 142 of the photographing unit 140. 150.

4 is an enlarged view of the lighting unit portion shown in FIGS. 2 and 3, and FIG. 5 is a right side view of FIG. 2 showing an excerpt of the lighting unit portion.

2 to 5, the illumination unit 120 is for irradiating light over the entire width direction of the optical film 10. desirable. As described below, the illumination unit 120 is divided into an odd illumination group 121 and an even illumination group 123 respectively corresponding to the odd camera group 141 and the even camera group 143. Odd and even illumination groups 121 and 123 are installed in the illumination frame 125 installed across the main frame 102.

The lighting unit 120 converts the light emitted from the LED 122 and the lighting module 124 including the plurality of LEDs 122 into a surface light source so that the optical film 10 can be irradiated to the optical film 10. A light guide plate 126 having a length greater than the width of the light guide plate, a lighting case 128 in which the lighting module 124 and the light guide plate 126 can be installed, and a fin for dissipating heat generated from the LED 122 to the outside. It is provided with a heat radiation member 127 having a structure. It will be appreciated by those skilled in the art that the number or arrangement of LEDs 122 of the lighting unit 120 may be replaced by other lighting in a known manner. In addition, numerals (original characters) in FIG. 5 indicate the arrangement order of the cameras in the width direction of the optical film 10.

6 is a right side view of FIGS. 2 and 3 showing an excerpt of the first filter unit portion.

2, 3, and 6, the first filter unit 130 includes a polarization filter for polarizing light emitted from the illumination unit 120. As will be described later, the polarizing filter includes a single elongated filter sheet 132, 134 disposed long in the width direction of the optical film 10. The first filter unit 130 has a function of supplementing the function of the circular polarization filter 154 of the second filter unit 150 and limiting the saturation of light according to the phase change.

Device 100 according to a preferred exemplary embodiment of the present invention can inspect the FPR film used in the In-Plane Swithcing (IPS) panel or the FPR film used in the twisted nematic (TN) panel, respectively. Therefore, the apparatus 100 should use a polarizing filter (sheet) having different specific angles as the first filter unit 130 to correspond to the type of the optical film 10 to be inspected. For example, the FPR film for the IPS panel is applied to the front surface of the alignment film at an angle of 45 degrees, the mask is mounted on the exposure machine, and then the UV absorbed energy is absorbed in the section where the alignment film rotates at an angle of 135 degrees, the liquid crystal thereon The layers were applied to form a patterned pair with a final angle of 45 degrees and 135 degrees, while the FPR film for the TN panel applied an alignment film at an angle of 0 degrees, and energized to rotate the liquid crystal layer by 90 degrees. Apply to form a pattern pair at an angle of 0 degrees and 90 degrees. Therefore, the first filter unit 130 needs to use filter sheets 132 and 134 having different inherent angles according to the types of angles formed by the pattern pairs of the optical film 10 to be inspected. Therefore, the apparatus 100 according to the present embodiment makes it possible to select any one between two filter sheets 132 and 134 having an intrinsic polarization angle suitable for the IPS panel and the TN panel as described above. To this end, the apparatus 100 has a filter conveying member 136. That is, the filter transfer member 136 may have different optimum angles corresponding to the optical characteristics of the optical film 10 on the focal line FL (see FIG. 6) formed by the illumination unit 120 and the imaging unit 140. The first filter sheet 132 and the second filter sheet 134 having characteristics may be selectively positioned. The specific working principle is described in detail below.

The first filter unit 130 is provided with a first through slit 138a and a second through slit 138b each formed long in the width direction of the optical film 10 so that the light of the illumination unit 120 can be transmitted. And the first filter sheet 132 and the second filter sheet 134 are positioned to block the first filter bracket 138, the first through slit 138a, and the second through slit 138b, respectively. In this state, a plurality of fixing pieces 138c are provided to fix the edges of the first filter sheet 132 and the second filter sheet 134 to the first filter bracket 138. In addition, the first filter unit 130 may include the odd first filter group 131 installed at the position corresponding to the odd camera group 141 and the even first filter group 133 installed at the position corresponding to the even camera group 143. ). In the odd and even first filter groups 131 and 133, a first filter sheet 132 and a second filter sheet 134 are installed in the first filter bracket 138 having the same structure. Thus, the operation of the odd and even first filter groups 131 and 133 is the same.

7 is a conceptual view for explaining the operation of the first filter unit by the filter feed member of the defect inspection apparatus of the optical film according to an exemplary embodiment of the present invention.

Referring to FIG. 7, the filter transfer member 136 is fixed to the pair of guide rods 135 and the first filter frame 137 provided at both ends of the first filter bracket 138, and the guide rods 135 are disposed. The guide block 139, which can be slidably inserted, has a position fixing part 139a provided in the guide block to fix the position of the first filter bracket 138. For example, when the inspected optical film 10 is used for the IPS panel, the second filter sheet 134 installed in the second through slit 138b is positioned in the focal line FL, and the inspected optical film ( When 10) is used for the TN panel, the guide rods 135 of the filter conveying member 136 move along the guide block 139 in the direction of arrow "A" to install the first filter installed in the first through slit 138a. The sheet 132 may be positioned at the focal line FL.

In an alternative embodiment, the filter conveying member 136 is preferably configured such that its position can be selectively adjusted by pneumatic or hydraulic pressure.

Fig. 8 is a left side view of Fig. 2 showing a portion of a photographing unit of a defect inspection apparatus according to an exemplary embodiment of the present invention.

As shown in FIGS. 2, 3, and 8, the photographing unit 140 is for continuously photographing the optical film 10 that is traveling, and a plurality of cameras 142 having a conventional structure and resolution are provided. It is provided.

The cameras 142 may include an odd camera group 141 including a plurality of odd cameras 142 spaced apart from each other at a first interval D1 predetermined in the width direction of the optical film 10, and an odd camera group. The first interval D1 of the first interval D1 may be photographed so as to photograph the width portions of the optical film 10 that are spaced apart by a predetermined interval in the travel direction of the optical film 10 from 141 and not photographed by the odd cameras 142. It is divided into an even camera group 143 including a plurality of even cameras 142 spaced apart from each other at a second predetermined interval D2 so as to focus on a center.

The odd cameras 142 belonging to the odd camera group 141 and the even cameras 142 belonging to the even camera group 143 respectively cross the main frame 102 in parallel with the width direction of the optical film 10. The odd group frames 145 and the even group frames 147 are disposed and spaced apart from each other in the vertical direction. Therefore, since each of the odd cameras 142 belonging to the odd camera group 141 and the respective cameras 142 belonging to the even camera group 143 are arranged in a zigzag pattern, the traveling optical film 10 is first Odd regions excluding the intervals spaced apart by the first interval D1 in the width direction of the optical film 10 are photographed by the cameras 142 of the odd camera group 141, and then the even camera group 143 Even areas are taken by the even cameras 142. The first interval D1 between each odd camera 142 belonging to the odd camera group 141 and the second interval D2 between each even camera 142 belonging to the even camera group 143 are equal to each other. Preferably, each adjacent first spacing D1 and second spacing D2 are preferably overlapping or bordering each other in the widthwise edges when positioned on the same line.

Each of the cameras 142 has a resolution of approximately 35 micrometers, for example, and a known camera having a capability of capturing 900 to 1200 images per second may be used. The number of installation of the cameras 142 installed in the photographing unit 140 may be arranged differently according to the length of the width of the optical film 10 used for the resolution of each camera 142. In addition, the apparatus 100 according to the present exemplary embodiment may provide a sufficient number of cameras 142 and may turn off a camera that does not need an operation to correspond to the width of the optical film 10 to be inspected.

Referring to FIG. 8, the second filter unit 150 is irradiated to the illumination unit 120 to separate the L and R patterns of the optical film 10 from each other and to use a circular polarization filter 154 for controlling scattering of light. Equipped. Circular polarization filter 154 includes filter module 158 assembled in a circle. The filter module 158 is fixedly installed at the end of each camera 142 of the photographing unit 140. It will be understood by those skilled in the art that the module structure of the circular polarization filter 154 of the second filter unit 150 and the installation structure for the camera 142 can be appropriately selected within a range that does not impair optical characteristics. In addition, those skilled in the art will understand that the connection between the filter module 158 and the end of the camera 142 of the photographing unit 140 may be made by various methods such as screwing, fitting, coupling, connectors, and the like.

Referring back to FIG. 2, the defect inspection apparatus 100 of the optical film according to the preferred embodiment of the present invention is based on the position information of the defect shown in each image photographed by the cameras 142 of the photographing unit 140. A marking unit 190 may be further provided on the surface of the optical film 10 that corresponds to the driving unit. The marking unit 190 is controlled by a control unit described later.

9 is an enlarged view of a portion of the marking unit shown in FIG. 2.

2 and 9, the marking unit 190 is disposed approximately 20 mm apart from the optical film 10 so that a marker of a predetermined pattern (eg, a circular annular shape) can be marked on corresponding position information of the optical film. Injectors 192 having a plurality of annular spouts.

Each injector 192 intermittently switches the ink stored in the ink reservoir 194 by pneumatic pressure by selectively turning on and off the marking body 196, in which the ink reservoir 194, in which ink can be stored, can be installed, and the jet port. A solenoid valve 198 can be provided. The ink reservoir 194 has a cartridge structure that can be detachably coupled to the marking body 196. Thus, when the ink in the ink reservoir 194 is exhausted, it can be replaced with a new cartridge.

The defect inspection apparatus 100 of the optical film according to an exemplary embodiment of the present invention, as described above, the control unit that can calculate and store the position information of the defect displayed on the images taken by the photographing unit 140 (Not shown), and a display unit (not shown) capable of displaying respective images.

It will be understood by those skilled in the art that the control unit may be set up to be related to the overall flow of performing the functions of the device 100.

In the defect inspection apparatus 100 of the optical film according to the present embodiment, each image photographed by the camera 142 of the photographing unit 140 is a continuous state of the vertical black and white stripes (L pattern and R pattern) When a predetermined portion of the white stripe is damaged in a circular or dot form, the damaged dot is inspected for a bright spot or a dark spot that appears to be a black dot due to image inversion, or a defect caused by scratching on a portion of the white stripe ( Scratch scratch) can be inspected. All of these 3D defects are defects in which a phase change occurs because a liquid crystal layer and an alignment layer are damaged during the production process of the optical film 10.

10... Optical film 14... materials
16 ... Alignment layer 18... Liquid crystal layer
100... . Defect inspection apparatus 120. Lighting unit
130 ... First filter unit 140... Shooting unit
150 ... Second filter unit 190... Marking Unit

Claims (18)

In the defect inspection apparatus of the optical film,
An illumination unit capable of irradiating light onto the optical film;
A first filter unit disposed between the optical film and the illumination unit;
A photographing unit provided to face the illumination unit so as to photograph the optical film; And
A second filter unit disposed between the optical film and the photographing unit,
The first filter unit may include filters including first and second polarization filters having different characteristics with optimal angles corresponding to optical characteristics of the optical film on a focal line formed by the illumination unit and the photographing unit. And a filter conveying member capable of selectively positioning any one of them.
The method according to claim 1,
The optical film is a defect inspection apparatus of the optical film, characterized in that the patterned retard film (FPR) formed with L and R patterns having different optical axes.
The method according to claim 2,
The FPR defect inspection apparatus of the optical film, characterized in that in the in-line (IN-Line) state before the winding on the winder while the substrate on which the alignment layer and the liquid crystal layer is formed.
The method according to any one of claims 1 to 3,
The optical film travels at a predetermined speed;
The photographing unit is one or more for photographing a predetermined area in the width direction of the optical film represented by a value combined by the first and second filter units in a state where light is irradiated through the illumination unit. The defect inspection apparatus of the optical film characterized by including cameras.
The method of claim 4,
The cameras are:
An odd camera group including a plurality of odd cameras spaced apart from each other at first predetermined intervals in a width direction of the optical film; And
To focus on a center of the first interval so as to photograph a width portion of the optical film which is spaced apart from the odd camera group by a predetermined interval in the advancing direction of the optical film and not photographed by the odd cameras; And an even camera group comprising a plurality of even cameras spaced apart from each other at a second predetermined interval.
The method according to any one of claims 1 to 3,
The illuminating unit can irradiate light over the entire width direction of the optical film, wherein the defect inspection apparatus of the optical film.
The method of claim 6,
The lighting unit is:
A plurality of LED lights installed in the light frame; And
And a light guide plate for converting light emitted from the LED lights into a surface light source and irradiating the optical film.
The method according to any one of claims 1 to 3,
And said first filter unit comprises a polarizing filter.
The method according to claim 8,
The polarizing filter has a single elongated filter sheet arranged long in the width direction of the optical film, characterized in that the defect inspection apparatus of the optical film.
delete The method according to claim 1,
The filter conveying member is:
A first filter bracket disposed to be spaced apart from the optical film by a predetermined distance so as to be parallel to the optical film and having first through slit and second through slit through which light of the illumination unit can be transmitted;
A first filter sheet and a second filter sheet respectively provided in the first through slit and the second through slit; And
And a guide portion provided between the first filter bracket and the first filter frame to selectively move the first filter bracket.
The method according to claim 5,
The first filter unit may be divided into an odd first filter unit corresponding to the odd camera group and an even first filter unit corresponding to the even camera group.
The method according to any one of claims 1 to 3,
And the second filter unit includes a circular polarizing filter for separating the L and R patterns of the optical film and controlling scattering of light.
The method according to claim 13,
And a filter module assembled in a circular polarizing filter circle.
The method according to claim 14,
And the filter module is integrally disposed at the end of the photographing unit.
The method according to claim 14,
The photographing unit includes a plurality of cameras;
The filter module is the defect inspection apparatus of the optical film, characterized in that fixed to the lens end of each camera.
The method according to any one of claims 1 to 3,
And a marking unit capable of marking the presence or absence of a defect on the surface of the optical film traveling to correspond to the positional information of the defect shown in the image photographed by the photographing unit.
The method according to any one of claims 1 to 3,
A control unit capable of calculating and storing position information of defects displayed on the images photographed by the photographing unit; And
And a display unit capable of displaying the respective images.

Images