Resin film manufacturing apparatus, resin film manufacturing method, and resin film inspection method

Abstract

To provide an apparatus for manufacturing a resin film which includes an inspection device that dispenses with a dark room for inspection and is compact.SOLUTION: An apparatus for manufacturing a resin film includes a conveyance device for continuously conveying a long resin film, and an inspection device for inspecting the continuously conveyed resin film, wherein the inspection device includes a light source for irradiating a main surface of the resin film conveyed by the conveyance device with parallel rays and an imaging device, the imaging device includes a telecentric lens and an imaging element, and the telecentric lens receives transmission light of the parallel rays with which the main surface of the resin film is irradiated and allows the imaging element to form an image.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a resin film manufacturing apparatus, a resin film manufacturing method, and a resin film inspection method. [Background technology]

[0002] Display devices such as liquid crystal display devices and organic electroluminescence display devices may include resin films formed from resin as optical elements. Using resin films with optical defects as optical elements may degrade product quality. Therefore, in the process of manufacturing resin films, inspections for the presence or absence of defects are carried out using various methods.

[0003] For example, a system has been devised that acquires an image of a defect in an optical film projected onto a screen, thereby acquiring the defect in the optical film (see Patent Document 1).

[0004] In addition, an inspection device has been devised that includes a first inspection means that irradiates the film with inspection light from the normal direction of the film surface and performs inspection using the transmitted light, and a second inspection means that irradiates the film with inspection light from an angle smaller than 90° and performs inspection using the transmitted light (see Patent Document 2).

[0005] Furthermore, a method has been devised for determining the type of defect using data including reflection image data and transmission image data of a film (see Patent Document 3). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2019-516989 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-298416 [Patent Document 3] Japanese Patent Application Laid-Open No. 2012-167975 Summary of the Invention [Problem to be solved by the invention]

[0007] However, a system that projects a defect image onto a screen, such as the technology of Patent Document 1, requires a darkroom for inspection, which makes the film manufacturing equipment complex.

[0008] Furthermore, inspection devices equipped with multiple inspection means, such as the technology of Patent Document 2, and inspection devices that use both reflected light and transmitted light, such as the technology of Patent Document 3, tend to require a large amount of space for installation, which can make it difficult to install them in a film manufacturing device.

[0009] Therefore, there is a demand for a compact resin film manufacturing device that includes an inspection device that does not require a darkroom for inspection; a resin film manufacturing method that can be performed using a compact device without requiring a darkroom; and a resin film inspection method that can be performed using a compact device without requiring a darkroom. [Means for solving the problem]

[0010] As a result of intensive research into solving the above-mentioned problems, the inventors discovered that the above-mentioned problems can be solved by making the inspection device included in the resin film manufacturing device include a specific light source and a specific imaging device, and thus completed the present invention. That is, the present invention provides the following.

[0011] [1] A method for manufacturing a resin film manufacturing machine, comprising: a conveying device for continuously conveying a long resin film; and an inspection device for inspecting the continuously conveyed resin film; the inspection device includes a light source that irradiates a main surface of the resin film transported by the transport device with parallel light rays and an imaging device, the imaging device includes a telecentric lens and an imaging element; The telecentric lens receives parallel light rays irradiated onto a main surface of the resin film and transmits the light to form an image on the imaging element. [2] A plurality of the imaging devices are included, [1] A resin film manufacturing apparatus as described in [1], wherein a plurality of the imaging devices are arranged so that the intersection P between the optical axis of the telecentric lens included in the imaging device and the main surface of the resin film is aligned along a straight line parallel to the width direction of the resin film. [3] A resin film manufacturing apparatus as described in [2], wherein the plurality of imaging devices are arranged so that the signs of the angles formed between the optical axes of the telecentric lenses corresponding to adjacent intersection points P and the perpendicular to the main surface of the resin film are opposite. [4] The resin film manufacturing device described in any one of [1] to [3], wherein the angle between the optical axis of the telecentric lens and the perpendicular to the main surface of the resin film, and the angle between the optical axis of the light source and the perpendicular to the main surface of the resin film are each changeable. [5] The resin film manufacturing device according to any one of claims [1] to [4], wherein the distance between the imaging device and the main surface of the resin film is changeable. [6] A step of continuously conveying a long resin film; A step of irradiating a main surface of the resin film being transported with parallel light; a step in which a telecentric lens receives transmitted light of parallel light irradiated onto the main surface of the resin film and forms an image on an imaging element; A method for producing a resin film, comprising: [7] A step of continuously conveying a long resin film; A step of irradiating a main surface of the resin film being transported with parallel light; a step in which a telecentric lens receives transmitted light of parallel light irradiated onto the main surface of the resin film and forms an image on an imaging element; A resin film inspection method comprising: [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a compact resin film manufacturing device including an inspection device that does not require a darkroom for inspection; a resin film manufacturing method that can be performed using a compact device without requiring a darkroom; and a resin film inspection method that can be performed using a compact device without requiring a darkroom. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a side view that schematically shows a resin film manufacturing apparatus according to one embodiment of the present invention. [Figure 2] FIG. 2 is a front view schematically showing an inspection device included in a resin film manufacturing apparatus according to one embodiment of the present invention. [Figure 3] FIG. 3 is a perspective view that schematically shows a part of an inspection device included in a resin film manufacturing apparatus according to one embodiment of the present invention. [Figure 4] FIG. 4 is a schematic diagram showing the imaging range of an imaging device included in a resin film manufacturing apparatus according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described in detail below with reference to embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and can be modified and implemented as desired without departing from the scope of the claims of the present invention and their equivalents. The components of the embodiments shown below can be combined as appropriate. In addition, in the drawings, the same components are designated by the same reference numerals, and their description may be omitted.

[0015] In the following description, a "long" film refers to a film having a length that is 5 times or more its width, preferably 10 times or more its width, and specifically refers to a film having a length that can be wound into a roll for storage or transportation. There is no particular upper limit to the length of the film, and it can be, for example, 100,000 times or less its width.

[0016] In the following description, the term "(meth)acrylic" encompasses "acrylic", "methacrylic", and combinations thereof.

[0017] In the following description, unless otherwise specified, the directions of elements as "parallel," "vertical," and "orthogonal" may include an error within a range that does not impair the effects of the present invention, for example, within a range of ±3°, ±2°, or ±1°.

[0018] [1. Resin film manufacturing equipment] A resin film manufacturing apparatus according to one embodiment of the present invention includes a conveying device that continuously conveys a long resin film and an inspection device that inspects the continuously conveyed resin film. The inspection device includes a light source and an imaging device that irradiates a main surface of the resin film conveyed by the conveying device with parallel light. The imaging device includes a telecentric lens and an imaging element. The telecentric lens receives transmitted light of the parallel light irradiated onto the main surface of the resin film and forms an image on the imaging element.

[0019] The resin film manufacturing apparatus of this embodiment includes a light source that irradiates parallel light rays and a telecentric lens that receives transmitted light and forms an image on an imaging element, thereby enabling inspection of defects in the resin film with a simple configuration. Therefore, the inspection device included in the resin film manufacturing apparatus of this embodiment can be made compact, and ultimately the resin film manufacturing apparatus itself can be made compact. Furthermore, the resin film manufacturing apparatus can be configured without requiring a darkroom.

[0020] The resin film manufacturing apparatus of this embodiment will be described below with reference to the drawings. Fig. 1 is a side view schematically showing a resin film manufacturing apparatus according to one embodiment of the present invention, Fig. 2 is a front view schematically showing an inspection device included in the resin film manufacturing apparatus according to one embodiment of the present invention, and Fig. 3 is a perspective view schematically showing a part of the inspection device included in the resin film manufacturing apparatus according to one embodiment of the present invention.

[0021] 1, a resin film manufacturing apparatus 1000 according to this embodiment includes conveying rolls 11, 12, 13, and 14 as conveying devices, and an inspection device 100. The inspection device 100 includes light sources 110a, 110b, 110c, and 110d, and imaging devices 120a, 120b, 120c, and 120d.

[0022] The long resin film 1 is extruded from a die (not shown), cast onto a casting roll (not shown), transported in sequence by transport rolls 11, 12, 13, and 14 as transport devices, and wound into a roll by a winding machine 15. The transport roll 12 and the transport roll 13 are both in contact with one of the main surfaces 1D of the resin film 1 and can transport the resin film 1 by rotating.

[0023] The resin film 1 may be continuously transported by a transport device other than these transport rolls. For example, the transport device may include any element for continuously transporting the resin film 1, such as a nip roll or a drive device.

[0024] 1 and 2, a plurality of light sources 110a, 110b, 110c, and 110d are arranged on one main surface 1D side of the resin film 1. The light sources 110a, 110b, 110c, and 110d are attached to a stand 150 and are arranged so as to irradiate light beams onto the main surface 1D side of the resin film 1 transported by the transport rolls 12 and 13.

[0025] The light sources 110a, 110b, 110c, and 110d are configured to emit parallel light beams. The light sources 110a, 110b, 110c, and 110d may be light sources that combine a light-emitting element with a collimator. The type of collimator combined with the light-emitting element is not particularly limited, and either a reflective collimator or a refractive collimator may be used.

[0026] The light emitted by the light sources 110a, 110b, 110c, and 110d may be light having a wavelength in the visible light range, infrared light, or ultraviolet light. The light source may include, for example, a light emitting element such as a metal halide lamp or a light emitting diode.

[0027] The light sources 110a, 110b, 110c, and 110d are preferably arranged so that the parallel light beams they emit are parallel to the optical axis of a telecentric lens (described later). This makes it possible to detect various types of defects.

[0028] A plurality of imaging devices 120a, 120b, 120c, and 120d are attached to the mount 150 and arranged on the other main surface 1U side of the resin film 1. The imaging devices 120a, 120b, 120c, and 120d include telecentric lenses 121a, 121b, 121c, and 121d and imaging elements 122a, 122b, 122c, and 122d, respectively.

[0029] The telecentric lenses 121a, 121b, 121c, and 121d are optical elements having a telecentric optical system, which means that the chief ray is parallel to the optical axis. The telecentric lenses 121a, 121b, 121c, and 121d may have object-side telecentricity, image-side telecentricity, or bilateral telecentricity, and preferably have image-side telecentricity. The telecentric lenses 121a, 121b, 121c, and 121d may be configured with a plurality of elements such as a lens, a diaphragm, and a mirror.

[0030] As the imaging elements 122a, 122b, 122c, and 122d, for example, solid-state imaging elements such as a CCD (Charge Coupled Device) solid-state imaging element and a CMOS (Complementary Metal Oxide Semiconductor) solid-state imaging element can be used.

[0031] The imaging devices 120a, 120b, 120c, and 120d may be connected to an image processing device, which will be described later.

[0032] In this embodiment, the inspection apparatus is equipped with multiple light sources and multiple imaging devices, but in another embodiment, the inspection apparatus may be equipped with only one light source and only one imaging device. Furthermore, the number of light sources and the number of imaging devices equipped in the inspection apparatus are each four in this embodiment, but are not particularly limited, and may be, for example, two, three, five, six, seven, eight, nine, or ten. The number of light sources and the number of imaging devices equipped in the inspection apparatus may or may not match. Preferably, the number of light sources and the number of imaging devices equipped in the inspection apparatus are the same.

[0033] The inspection apparatus 100 has the following advantages by including the plurality of light sources 110a, 110b, 110c, and 110d and the plurality of image capturing devices 120a, 120b, 120c, and 120d. In order to capture an image of the resin film 1 across its entire width using one light source and one imaging device, a telecentric lens is typically used whose diameter is equal to or larger than the width of the resin film 1. This is because the angle of view of a telecentric lens is usually 0° or close to it. On the other hand, when imaging the resin film 1 across its entire width using multiple light sources and multiple imaging devices, the telecentric lens included in the imaging device can usually have a diameter smaller than the width of the resin film 1. This allows the size of the inspection device 100 to be made more compact.

[0034] The imaging devices 120a, 120b, 120c, and 120d are arranged in the space on the main surface 1U side of the resin film 1 so that the intersections Pa, Pb, Pc, and Pd of the optical axes C1a, C1b, C1c, and C1d of the telecentric lenses 121a, 121b, 121c, and 121d included in the imaging devices 120a, 120b, 120c, and 120d with the main surface 1U of the resin film 1 are aligned along a straight line L1 parallel to the width direction TD of the resin film 1. This allows the resin film 1 to be imaged across its entire width by the multiple imaging devices 120a, 120b, 120c, and 120d.

[0035] Here, the imaging devices 120a, 120b, 120c, and 120d may be arranged so that all of the multiple intersection points Pa, Pb, Pc, and Pd corresponding to the multiple imaging devices 120a, 120b, 120c, and 120d are located on the straight line L1, or the imaging devices 120a, 120b, 120c, and 120d may be arranged so that some or all of the multiple intersection points Pa, Pb, Pc, and Pd are located in the vicinity of the straight line L1 (preferably at positions where the distance from the straight line L1 is 700 mm or less).

[0036] FIG. 4 is a schematic diagram showing the imaging range of an imaging device included in a resin film manufacturing apparatus according to one embodiment of the present invention. 4, intersection Pa corresponding to imaging device 120a, intersection Pb corresponding to imaging device 120b, intersection Pc corresponding to imaging device 120c, and intersection Pd corresponding to imaging device 120d are aligned along a straight line L1 parallel to the width direction of resin film 1. Imaging range Aa, imaging range Ab, imaging range Ac, and imaging range Ad are imaging ranges on resin film 1 of imaging device 120a, imaging device 120b, imaging device 120c, and imaging device 120d, respectively. Imaging ranges Aa and Ab, imaging ranges Ab and Ac, and imaging ranges Ac and Ad each have a common range. Imaging devices 120a, 120b, 120c, and 120d are positioned so that straight line L1 passes through these common ranges, and imaging ranges Aa, Ab, Ac, and Ad of imaging devices 120a, 120b, 120c, and 120d are set. In this way, the image of the entire resin film 1 in the width direction can be captured by the imaging devices 120a, 120b, 120c, and 120d.

[0037] The multiple imaging devices 120a, 120b, 120c, and 120d are arranged so that the signs of the angles formed between the optical axes of the telecentric lenses corresponding to adjacent intersection points P and the perpendicular to the main surface 1U of the resin film 1 are opposite. However, the sign of the angle is positive when the optical axis can be made to coincide with the perpendicular to the main surface 1U of the resin film 1 by rotating the optical axis in one direction within a plane including the optical axis around the intersection point P, and the sign of the angle is negative when the optical axis can be made to coincide with the perpendicular to the main surface 1U of the resin film 1 by rotating the optical axis in the opposite direction within a plane including the optical axis around the intersection point P. By arranging multiple imaging devices 120a, 120b, 120c, 120d in this manner, it is possible to image the resin film 1 across the entire width direction using the multiple imaging devices.

[0038] The reasons are as follows: The telecentric lens included in the imaging device has an angle of view of 0° or close to it, so when multiple imaging devices are arranged in a row in the width direction of the resin film 1, there may be areas in the width direction of the resin film 1 that are not imaged. As described above, by arranging multiple imaging devices so that the signs of the angles formed between the optical axes of the telecentric lenses corresponding to adjacent intersection points P and the perpendicular to the main surface 1U of the resin film 1 are opposite, the imaging ranges of the multiple imaging devices on the resin film 1 can be made to overlap, so that the resin film 1 can be imaged across the entire width direction using the multiple imaging devices.

[0039] It is preferable that the absolute values ​​of the angles formed by the optical axes of the telecentric lenses corresponding to the adjacent intersection points P and the perpendicular line are the same or approximately the same. When the arithmetic mean value of the absolute value of the angle θ between the optical axis of the telecentric lens and the perpendicular to the main surface 1U of the resin film 1 is defined as θave, the value of θave-|θ| is preferably within the range of 0°±35°, more preferably within the range of 0°±25°, and even more preferably within the range of 0°±20°.

[0040] The arrangement of the multiple imaging devices 120a, 120b, 120c, and 120d in the manufacturing apparatus 1000 of this embodiment will be described with reference to FIG. As shown in Figure 3, the angle between the optical axis C1a of telecentric lens 121a corresponding to intersection point Pa and the perpendicular line Va of the principal surface 1U of the resin film 1 that passes through intersection point Pa is θa; the angle between the optical axis C1b of telecentric lens 121b corresponding to intersection point Pb adjacent to intersection point Pa and the perpendicular line Vb of the principal surface 1U of the resin film 1 that passes through intersection point Pb is θb; the angle between the optical axis C1c of telecentric lens 121c corresponding to intersection point Pc adjacent to intersection point Pb and the perpendicular line Vc of the principal surface 1U of the resin film 1 that passes through intersection point Pc is θc; and the angle between the optical axis C1d of telecentric lens 121d corresponding to intersection point Pd adjacent to intersection point Pc and the perpendicular line Vd of the principal surface 1U of the resin film 1 that passes through intersection point Pd is θd.

[0041] In this embodiment, θa has a positive sign, θb has a negative sign, θc has a positive sign, and θd has a negative sign. If the arithmetic mean of |θa|, |θb|, |θc|, and |θd| is θave, then the values ​​of (θave-|θa|), (θave-|θb|), (θave-|θc|), and (θave-|θd|) are each 0°.

[0042] The magnitude of the angle θ between the optical axis of the telecentric lens and the perpendicular to the main surface 1U of the resin film 1 is not particularly limited, but for example, the absolute value of θ (|θ|) can be, for example, 5° or more, for example, 10° or more, for example, 35° or less, or for example, 20° or less.

[0043] The imaging devices 120a, 120b, 120c, and 120d are attached to the mount 150 so that it is possible to change the angle θa between the optical axis C1a of the telecentric lens 121a and the perpendicular line Va to the principal surface 1U of the resin film 1, the angle θb between the optical axis C1b of the telecentric lens 121b and the perpendicular line Vb to the principal surface 1U of the resin film 1, the angle θc between the optical axis C1c of the telecentric lens 121c and the perpendicular line Vc to the principal surface 1U of the resin film 1, and the angle θd between the optical axis C1d of the telecentric lens 121d and the perpendicular line Vd to the principal surface 1U of the resin film 1. This makes it easy to adjust the inspection conditions.

[0044] Furthermore, the imaging devices 120a, 120b, 120c, and 120d are attached to a stand 150 so that the distance between each of the imaging devices 120a, 120b, 120c, and 120d and the main surface 1U of the resin film 1 can be changed. This makes it easy to adjust the inspection conditions.

[0045] Furthermore, the light sources 110a, 110b, 110c, and 110d are attached to the mount 150 so that the angles formed between the optical axes of the light sources 110a, 110b, 110c, and 110d and the perpendicular to the main surface 1U of the resin film 1 can be changed. This makes it easy to adjust the inspection conditions.

[0046] The imaging devices 120a, 120b, 120c, and 120d and the light sources 110a, 110b, 110c, and 110d can be attached to the mount 150 by any means, for example, by an attachment means such as a member having a gimbal mechanism.

[0047] The resin film 1 may have a single-layer structure or a multi-layer structure.

[0048] The resin film 1 is made of and contains a resin. Examples of the resin that forms the resin film 1 include thermoplastic resins. The resin may generally contain a polymer. Examples of polymers include cellulose-based polymers (e.g., triacetyl cellulose); polymers containing an alicyclic structure (e.g., cycloolefin polymers); polyesters (e.g., polyethylene terephthalate); acrylic polymers (e.g., poly(meth)acrylic acid, poly(meth)acrylic acid ester, polyacrylonitrile); polycarbonate; polystyrene; polyamide; polyvinyl chloride; polyvinyl acetate; and polyolefins. The resin forming the resin film 1 may contain one type of polymer alone or a combination of two or more types. The polymer may be a homopolymer or a copolymer. The resin may contain any additive in addition to the polymer.

[0049] Examples of polymers containing an alicyclic structure include (1) norbornene-based polymers, (2) monocyclic olefin polymers, (3) cyclic conjugated diene polymers, (4) vinyl alicyclic hydrocarbon polymers, and hydrogenated versions thereof. Among these, norbornene-based polymers and hydrogenated versions thereof are preferred from the viewpoints of transparency and moldability.

[0050] Examples of norbornene-based polymers include ring-opening polymers of monomers having a norbornene structure and their hydrogenated products; and addition polymers of monomers having a norbornene structure and their hydrogenated products. Examples of ring-opening polymers of monomers having a norbornene structure include ring-opening homopolymers of one type of monomer having a norbornene structure, ring-opening copolymers of two or more types of monomers having a norbornene structure, and ring-opening copolymers of a monomer having a norbornene structure and any monomer copolymerizable therewith. Examples of addition polymers of monomers having a norbornene structure include addition homopolymers of one type of monomer having a norbornene structure, addition copolymers of two or more types of monomers having a norbornene structure, and addition copolymers of a monomer having a norbornene structure and any monomer copolymerizable therewith. Examples of these polymers include the polymers disclosed in, for example, JP 2002-321302 A.

[0051] Specific examples of suitable norbornene polymers and hydrogenated products thereof include "ZEONOR" manufactured by Nippon Zeon Co., Ltd., "ARTON" manufactured by JSR Corporation, and "TOPAS" manufactured by TOPAS ADVANCED POLYMERS.

[0052] The resin film 1 to be inspected preferably has high transparency. The haze of the resin film 1 is preferably 5% or less, more preferably 3% or less, even more preferably 1% or less, and is usually 0% or more. This allows the resin film 1 to be inspected for defects with high accuracy.

[0053] The inspection device 100 can inspect various defects in the resin film 1. The inspection device 100 can inspect for defects such as linear defects and point defects, for example.

[0054] [2. Resin film manufacturing method] A method for producing a resin film using the resin film production apparatus 1000 will be described below. A method for producing a resin film according to one embodiment of the present invention includes the steps of continuously transporting a long resin film (hereinafter also referred to as step (1)), irradiating a main surface of the transported resin film with parallel light (hereinafter also referred to as step (2)), and using a telecentric lens to receive the transmitted light of the parallel light irradiated onto the main surface of the resin film and form an image on an imaging element (hereinafter also referred to as step (3)). Steps (1), (2), and (3) are usually performed simultaneously.

[0055] (Process (1)) In step (1), a long resin film 1 is continuously transported by, for example, transport rolls 11, 12, 13, and 14 serving as a transport device.

[0056] (Process (2)) In step (2), a parallel beam of light is irradiated onto the main surface 1D of the resin film 1 being transported. The parallel light beams can be emitted, for example, by a plurality of light sources 110a, 110b, 110c, and 110d. The parallel light beams are preferably parallel to the optical axes of the telecentric lenses 121a, 121b, 121c, and 121d.

[0057] (Step (3)) In step (3), a telecentric lens receives the parallel light beams irradiated onto the main surface of the resin film and transmitted therethrough, and forms an image on an imaging element. The telecentric lenses are, for example, a plurality of telecentric lenses 121a, 121b, 121c, and 121d, which receive transmitted parallel light beams emitted from, for example, a plurality of light sources 110a, 110b, 110c, and 110d. The telecentric lenses 121a, 121b, 121c, and 121d form images of the received transmitted light beams of the resin film 1 on, for example, a plurality of image pickup elements 122a, 122b, 122c, and 122d.

[0058] (Step (4)) The method for producing a resin film according to the present embodiment may include a step (4) in addition to the steps (1) to (3). The step (4) is usually carried out after the steps (2) to (3). Step (4) is a step of processing the image data obtained by the imaging element to detect defects. For example, step (4) is performed by an image processing device. For example, the image processing device includes an input interface, an output interface, a CPU (Central Processing Unit), a main memory device, and an auxiliary memory device. The input interface, output interface, CPU, main memory device, and auxiliary memory device are connected by a bus and exchange data and control information. The CPU reads and executes a program stored in the main memory device, causing the image processing device to function as an image processing unit that processes image data and a defect detection unit that detects defects in the resin film based on the processed image data. The input interface is connected to, for example, image capture devices 120a, 120b, 120c, and 120d. The output interface is connected to, for example, a display, which can display the inspection results of the resin film.

[0059] Step (4) may include step (4a) and step (4b). In step (4a), the image processing unit of the image processing device processes the image data obtained by the imaging element. In step (4b), a defect detection unit of the image processing device detects defects in the resin film based on the processed image data. The defect detection unit may detect the presence or absence of defects in the resin film, as well as at least one of the type and size of the defects.

[0060] (Other optional steps) The method for producing a resin film according to the present embodiment may include any step other than steps (1) to (4). For example, when a long resin film is produced by a melt extrusion method, the method may include a step of extruding a molten resin through a die and a step of cooling the extruded film on a cast roll. For example, when a long resin film is produced by a solution casting method, the method may include a step of casting a solution containing a resin and a step of drying the cast solution.

[0061] Furthermore, the method for producing a resin film of this embodiment may include, for example, a step of stretching the resin film, a step of winding the resin film on a winder 15, and a step of cutting the resin film. The step of stretching the resin film may be performed before steps (1) to (3) or after steps (1) to (3). By including the steps (1) to (3) in the resin film manufacturing method, a resin film that has been inspected for defects can be manufactured using a compact device without requiring a darkroom.

[0062] [3. Inspection method for resin film] A resin film inspection method according to one embodiment of the present invention includes the step (1) of continuously transporting a long resin film, the step (2) of irradiating a main surface of the transported resin film with parallel light, and the step (3) of using a telecentric lens to receive the transmitted light of the parallel light irradiated onto the main surface of the resin film and form an image on an imaging element. The resin film inspection method may include any step in addition to the steps (1) to (3). For example, the resin film inspection method may include the step (4). By including steps (1) to (3) in the resin film inspection method, the resin film can be inspected for defects using a compact device without requiring a darkroom. [Explanation of symbols]

[0063] 1 Resin film 1D main surface 1U main surface 11, 12, 13, 14 Conveyor roll (conveyor device) 15 Winding machine 110a, 110b, 110c, 110d light source 120a, 120b, 120c, 120d Imaging devices 121a, 121b, 121c, 121d Telecentric Lenses 122a, 122b, 122c, 122d Image sensor 100 Inspection equipment 150 Mounting stand 1000 manufacturing equipment C1a, C1b, C1c, C1d optical axis Pa, Pb, Pc, Pd intersection Va, Vb, Vc, Vd perpendicular lines

Claims

1. The method includes: a conveying device that continuously conveys a long resin film; and an inspection device that inspects the continuously conveyed resin film, the inspection device includes a light source that irradiates a main surface of the resin film transported by the transport device with parallel light rays and a plurality of imaging devices, the plurality of imaging devices are arranged so that imaging ranges of the plurality of imaging devices on the resin film overlap with each other; the imaging device includes a telecentric lens and an imaging element; the telecentric lens receives parallel light rays irradiated onto a main surface of the resin film and transmits the parallel light rays to form an image on the imaging element; A resin film manufacturing apparatus in which a plurality of the imaging devices are arranged so that intersection points P between the optical axes of the telecentric lenses included in the imaging devices and the main surface of the resin film are aligned along a straight line parallel to the width direction of the resin film, and so that the signs of the angles θ formed between the optical axes of the telecentric lenses corresponding to adjacent intersection points P and the perpendicular to the main surface of the resin film are opposite, and the absolute value of the angle θ is 5° or more and 35° or less.

2. The resin film manufacturing apparatus according to claim 1, wherein the angle between the optical axis of the telecentric lens and the perpendicular to the main surface of the resin film, and the angle between the optical axis of the light source and the perpendicular to the main surface of the resin film are each changeable.

3. The resin film manufacturing apparatus according to claim 1 or 2, wherein a distance between the imaging device and a main surface of the resin film is changeable.

4. A step (1) of continuously transporting a long resin film; A step (2) of irradiating a main surface of the resin film being transported with parallel light; and a step (3) in which a plurality of telecentric lenses receive transmitted light of parallel light irradiated onto the main surface of the resin film and form an image on an imaging element; Including, a method for manufacturing a resin film, wherein the step (3) is performed so that intersections P between the optical axes of the telecentric lenses and the main surface of the resin film are aligned along a straight line parallel to the width direction of the resin film, so that the signs of the angles θ formed between the optical axes of the telecentric lenses corresponding to adjacent intersections P and the normal to the main surface of the resin film are opposite and the absolute value of the angle θ is 5° or more and 35° or less, and so that the imaging ranges on the resin film of multiple imaging devices including the telecentric lenses overlap.

5. A step (1) of continuously transporting a long resin film; A step (2) of irradiating a main surface of the resin film being transported with parallel light; and a step (3) in which a plurality of telecentric lenses receive transmitted light of parallel light irradiated onto the main surface of the resin film and form an image on an imaging element; Including, A method for inspecting a resin film, wherein the step (3) is performed so that intersections P between the optical axes of the telecentric lenses and the main surface of the resin film are aligned along a straight line parallel to the width direction of the resin film, so that the signs of the angles θ formed between the optical axes of the telecentric lenses corresponding to adjacent intersections P and the normal to the main surface of the resin film are opposite and the absolute value of the angle θ is 5° or more and 35° or less, and so that the imaging ranges on the resin film of multiple imaging devices including the telecentric lenses overlap.

Images