JP4701803B2 - Optical film inspection method and inspection apparatus - Google Patents

Description

  The present invention relates to an inspection method and an inspection apparatus for a long optical film that is continuously conveyed.

  Optical films such as antiglare films, antireflection films, retardation films, optical compensation films, brightness enhancement films, hard coat films, polarizing plate protective films used in display devices such as liquid crystal display devices (LCDs) As demanded quality increases, stringent requirements are imposed, and it is therefore increasingly important to inspect the properties of optical films during the manufacturing process. As an optical film inspection device, optical input means (for example, a CCD camera) is used to capture the data of the inspection location of the optical film and determine whether this data matches the set normal data. What performs an inspection by doing is known.

  In this inspection, when the optical film always moves along a certain plane, since the focal point of the optical input means always matches the distance to the film, continuous normal inspection is possible. In the case of an optical film, there is a property that the film inspection location shifts from the inspection reference position where normal inspection can be performed due to eccentricity of a roll that conveys the film, fluctuation of conveyance tension, deformation due to wind or vibration, etc. There was a problem that the inspection could not be performed accurately due to the deviation.

Therefore, in order to solve this problem, Patent Document 1 discloses an optical input means for moving a traveling sheet-like object up and down in a range larger than the vertical movement range, and between the sheet-like object and the optical input means. Displacement amount measuring means for outputting an inspection start signal to the image processing device when the distance of the in-focus position is ± focus depth, a strobe illumination device for emitting strobe light when the inspection start signal is output, and an optical input There is disclosed a ring-shaped optical fiber light guide that is installed between a means and the sheet-like material to perform reflected illumination, and a sheet-like material defect inspection device comprising an image processing device.
Japanese Unexamined Patent Publication No. 6-242024

  According to the inspection apparatus of Patent Document 1 described above, data is captured only when the focal points coincide with each other. Therefore, for a long optical film that is continuously conveyed at high speed, it is only an intermittent inspection, and it is accurate. There was a problem that it was not enough.

  An object of the present invention is to provide an optical film inspection method and inspection apparatus capable of continuously and accurately inspecting a continuously transported long optical film.

The optical film inspection method according to the present invention is an optical film inspection method for inspecting the film characteristics of a continuously transported long optical film by using an optical input means. The amount of displacement from the inspection reference position of the inspection location is measured by the displacement amount measuring means, and the continuous optical transport is inspected while optical input means is driven according to the displacement amount, and optical input is performed. wherein upon driving means, to previously obtain the displacement amount change characteristic for predicting the change in the displacement amount of the film to be inspected point, that you adjust the drive amount of the optical input means in accordance with the displacement amount change characteristic It is what.

The present invention an optical film inspection apparatus according to, meet optical film inspection apparatus for performing the above optical film inspection method, and a driving means for moving the optical input means, from the inspection reference position of the film to be inspected portion a displacement amount measuring means for measuring the amount of displacement, and a drive amount determination means for determining the drive amount of the optical input means in accordance with the output of the displacement measuring means, the drive quantity determining means, have been previously stored with displacement variation characteristic data is called a, the displacement measuring means, a new displacement variation characteristic data from the film being transported is obtained is characterized in Rukoto.

  The optical film inspection method and inspection apparatus according to the present invention can be applied to a long optical film made of various resin films such as cellulose ester, polyester, polycarbonate, cycloolefin resin, and in particular, a long length made of a cellulose ester resin film. In the manufacturing method of a long optical film, after forming a long optical film, it is used suitably in order to inspect whether the film characteristic is appropriate.

  In the present invention, the “optical film” means an antiglare film, an antireflection film, a retardation film, an optical compensation film, a brightness enhancement film, a hard coat film, a polarizing plate used in a display device such as a liquid crystal display (LCD). It is a collective term for films having optical functions such as protective films, and the `` long optical film '' is an optical film wound up in a roll shape or an optical film premised on being wound up. The length is 100 m or more, preferably 100 to 5000 m.

  A CCD camera, a film thickness sensor, or the like is used as the optical input means. The CCD camera may be used in a transmission system or may be used in a reflection system.

  The inspection reference position is, for example, the shortest transport position (a transport position when there is no film slack).

  As the displacement amount measuring means, measuring means called “displacement meter” or “displacement sensor” such as a laser displacement meter, an infrared displacement sensor, an eddy current displacement sensor, and an ultrasonic displacement sensor can be used.

  There are periodic and non-periodic displacements in the film inspection location, but periodic changes (eg, sine curves) are fundamental. Therefore, the driving of the optical input means is preferably performed according to a sine curve that changes periodically, and the amplitude, period, etc. thereof are adjusted as appropriate. Thereby, even if the film flutters, the distance between the inspected portion of the film and the optical input means is kept within a predetermined range, and continuous and accurate inspection can be performed.

  It is preferable to adjust the driving amount of the optical input means so that the distance between the optical input means and the film inspection location falls within a predetermined range.

  This range is determined based on the characteristics of the optical input means (focal length, depth of focus, etc. of the CCD camera).

  Further, it is preferable that a displacement amount change characteristic for predicting a change in the displacement amount of the film inspection location is obtained, and the drive amount of the optical input means is adjusted according to the displacement amount change characteristic. This displacement amount change characteristic is preferably determined based on the result of measuring the displacement amount of the inspected portion of the long optical film that is continuously conveyed.

  In this way, when the inspection location of the film is in the normal displacement range, an appropriate inspection is possible from the initial stage of the inspection, and the optical input means predicts the displacement direction of the inspection location of the film. Therefore, it is possible to stably perform an appropriate inspection even while the inspection is continued.

  It is preferable that the displacement amount measuring means measures a displacement amount of a portion to be inspected or the upstream side of the continuously conveyed long optical film.

  In this way, the optical input means can be driven early according to the displacement of the inspected portion of the film, and it is possible to appropriately cope with the non-periodic displacement of the inspected portion of the film. it can.

  It is preferable that a plurality of optical input means and displacement amount measuring means are arranged in the width direction of the long optical film.

  If it does in this way, a test | inspection with a sufficient precision can be performed also over the width direction of an optical film.

  The optical film inspection apparatus preferably further includes a relative distance measurement means for measuring the distance between the optical input means and the film inspection location. For this purpose, the displacement amount measurement means of the optical film inspection apparatus is an optical Sometimes it also serves as a relative distance measuring means for measuring the distance between the target input means and the film inspection location. The displacement amount measuring means may be arranged so as to be driven simultaneously with the optical input means.

  The displacement measuring means measures the displacement of the inspected portion of the film. Alternatively, it is preferable that the relative distance between the optical input means and the inspected portion of the film can be measured. From the measurement result, it can be confirmed that the optical input means is within a properly used range. For this purpose, it is of course possible to use two displacement sensors, one for measuring the displacement of the inspected portion of the film and the other for measuring the relative distance between the optical input means and the inspected portion of the film. A single displacement sensor may be used. And in the case of a single unit, the displacement sensor is arranged so as to be driven in conjunction with the optical input means, and the position of the displacement sensor is fixed before the inspection is started. After acquiring the quantity change characteristic data and starting the inspection, the displacement sensor is driven in conjunction with the optical input means, and the distance between the optical input means and the film inspection location is measured, and the correction is normally performed. It is preferable to be able to confirm whether or not

  According to the optical film inspection method and inspection apparatus of the present invention, the optical input means moves to an appropriate position in accordance with the amount of displacement of the film inspection location. Can be inspected. Further, it is possible to eliminate the restriction of the installation location for suppressing the displacement amount of the film inspection location.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 4 show a schematic configuration of an inspection apparatus for performing the optical film inspection method of the present invention.

  As shown in FIG. 1, the optical film inspection apparatus includes a transport means (1) having transport rolls (1a) and (1b) and a long optical film (F) continuously transported by the transport means (1). Optical input means (2) such as a CCD camera for capturing film characteristics, and a light source (2) provided on the same side as or opposite to the optical input means (2) to provide a predetermined amount of light to the optical input means (2) 3) and a displacement sensor (4) as a displacement measuring means for measuring the displacement amount from the reference position of the inspected portion (T) of the long optical film (F) on which the optical input means (2) is faced. ).

  A plurality (four in the figure) of optical input means (2), light source (3), and displacement measuring means (4) are arranged in the width direction of the long optical film (F).

  When inspecting a long optical film (F), the transport rolls (1a) and (1b) may be arranged so that the transport direction is 45 ° with respect to the horizontal plane, as shown in FIG. As shown in FIG. 3, the conveyance direction may be arranged horizontally, and as shown in FIG. 4, the conveyance direction may be arranged vertical. Further, when the optical input means (2) is a CCD camera, the positional relationship between the CCD camera (2) and the light source (3) is such that the light source (3) is connected to the CCD camera (L) through the long optical film (F). There are a transmission method (FIG. 2) arranged on the opposite side of 2) and a reflection method (FIG. 3) in which the light source (3) is arranged on the same side as the CCD camera (2). In addition to the CCD camera (2), what is called a film thickness sensor (5) may be used as the optical input means (FIG. 4).

  In foreign matter inspection and failure inspection, as shown in FIGS. 2 and 3, the arrangement place of the CCD camera or the like as the optical input means (2) is in the normal direction or oblique direction with respect to the long optical film. Any of them may be used, but in order to detect a smaller failure, it is preferable to arrange them in an oblique direction.

  When the distance between the optical input means (2) and the long optical film (F) is out of a predetermined range (for example, in-focus position ± focus depth), a correct inspection may not be performed. On the other hand, due to the eccentricity of rolls (1a) and (1b) transporting the long optical film (F), fluctuations in transport tension, deformation of the film due to wind and vibration, etc., (a) in FIG. As exemplified by d), there is a property that the film is shifted from the shortest conveyance position indicated by the solid line to the position indicated by the broken line.

  The optical film inspection method and the optical film inspection method of the present invention are made by paying attention to the deviation (flapping) of the long optical film (F), and are applicable to any of the above-described methods shown in FIGS. Even if there is a displacement to the position indicated by the broken line in FIG. 5, it is possible to suppress a decrease in inspection accuracy due to this displacement.

  FIG. 6 shows a detailed configuration (characteristic part) of the optical film inspection apparatus according to the present invention. As shown in FIG. 6, the optical film inspection apparatus is taken in by an optical input means (2) such as a CCD camera. Image processing means (6) for processing processed data, display (7) for displaying processed information, and inspected portion of the long optical film (F) where the optical input means (2) is faced Displacement measuring means (4) for measuring the amount of displacement from the inspection reference position of (T), and an optical input means (2) and a long optical film provided separately from this displacement measuring means (4) Relative distance measuring means (8) that measures the distance of (F) to the inspection location (T), optical input means (2), and relative distance measuring means (8) so that both can move integrally. A supporting means (9) for supporting, a driving means (10) for moving the supporting means (9), a displacement measuring means (4) and a relative distance. Drive amount determining means (11) for determining an appropriate drive amount of the support means (9) according to the output from the measuring means (8).

  According to this optical film inspection apparatus, the film characteristic information of the long optical film (F) being conveyed is captured by the optical input means (2), and this film characteristic is sent to the image processing means (6), Data processed. The image processing means (6) analyzes the characteristics of the optical film (F) being conveyed.For example, for foreign matters and failures, the type and size are specified, statistical processing such as appearance frequency, data storage, etc. Also implement. The processed information is displayed on the display (7) as needed, or fed back to change or adjustment of production conditions.

  FIG. 7 shows a state in which the film (F) is slackened and displaced downward as indicated by a solid line from the reference position (inspection reference position) indicated by a broken line due to a decrease in conveyance tension or the like. Due to this displacement, the position G on the inspection reference position is displaced to the actual inspection location T. In the inspection apparatus in which the optical input means (2) is fixed at the position indicated by the chain line in FIG. 7, since the optical input means (2) faces the position G, the actual position in the direction of the position G The film characteristic is measured at the position I. The distance between the optical input means (2) and the inspection location (T) of the film (F) is determined in advance, and has an allowable fluctuation range that allows accurate measurement. Therefore, when the displacement amount of the long optical film (F) that is continuously conveyed fluctuates beyond the allowable width, accurate measurement cannot be performed. Further, the position to be originally measured is considered to be the position of the inspection location T displaced from the reference position S with respect to the G position of the long optical film (F) continuously conveyed at the reference position S. However, in the inspection apparatus in which the optical input means (2) is fixed at the position of the chain line, the upstream side of the film (F) being conveyed (the downstream side may be depending on the arrangement of the apparatus constituent devices and the direction of film displacement). The measurement position on the film (F) is moved by the displacement of the film (F). Since measurement is performed continuously, there is a problem that measurement data between T and I is missing or accurate measurement cannot be performed.

  On the other hand, according to the optical film inspection apparatus of the present invention, the displacement amount of the inspection location (T) of the long optical film (F) continuously conveyed between the conveyance rolls (1a) (1b) is determined. Displacement measuring means (4) for measuring is provided, and information on how the inspection location (T) of the long optical film (F) is displaced can be obtained. Then, a displacement amount that is a deviation from the inspection reference position is continuously measured, and according to this displacement amount, the optical input means (2) is moved to a position indicated by a solid line in FIG. The inspected part (T) corresponding to the above can be inspected, and the measurement can be continuously performed without causing a measurement error due to the displacement of the film (F).

  In the drive amount determination means (11), the drive amount of the optical input means (2) is determined according to the amount of displacement of the film, and this is sent to the drive means (10), whereby the optical input means (2) is The film (F) is driven following the amount of displacement of the inspection location (T) from the inspection reference position.

  Further, according to the relative distance measuring means (8) for measuring the relative distance between the optical input means (2) and the inspected portion (T) of the long optical film (F), the optical input means (2) The relative distance to the inspection location (T) is continuously measured, and from this displacement data, it is confirmed whether the optical input means (2) is properly driven, and the optical input means (2). When there is a possibility that the relative distance from the film is out of the predetermined range, driving correction is performed via the driving means (10).

  When driving the optical input means (2), it is particularly preferable to predict and control the displacement amount at the next time point from the displacement amount, the change rate of the displacement amount, and the movement of the displacement amount change rate. Therefore, in the drive amount determination means (11), the fluctuation pattern of the displacement amount of the optical film being transported that was measured immediately before (displacement amount, displacement amount change rate, displacement period, displacement amount amplitude, etc.) Alternatively, it is preferable that the next displacement position is predicted from the current displacement amount, the displacement amount change, the displacement amount variation pattern, and the like by referring to the displacement amount variation pattern stored in advance. Then, the position of the optical input means (2) is moved in accordance with the predicted displacement pattern of the optical film. The long optical film (F) being conveyed fluctuates mainly periodically. For example, there is a tendency that the cycle becomes shorter as the transport speed increases. Also, the amplitude of displacement is often constant. If there is a fluctuation pattern of such a periodic displacement amount, if the absolute value of the displacement amount at a certain point in time and the rate of change of the displacement amount at that point are obtained, that is the cyclic variation pattern of the displacement amount. By referring to where it is, it is possible to predict the subsequent variation pattern, and the prediction accuracy is improved. Although the fluctuation pattern of the periodic displacement amount is expected to change depending on the production conditions, the displacement amount prediction according to the conditions is facilitated if the fluctuation pattern corresponding to them is provided. Further, it is preferable to always measure and accumulate displacement amount fluctuation data immediately before or after the start of actual inspection, and this data can be used for displacement amount prediction.

  In addition, the inspection location (T) of the optical film (F) that is continuously transported may be a non-periodic change case in addition to the case where the displacement amount changes periodically. For example, when the amount of displacement changes at a constant period and amplitude, the displacement suddenly increases to a larger amplitude, and the amplitude width gradually decreases. The displacement amount measuring means (4) of the present invention continuously measures the displacement amount, and stores information on the displacement amount variation that varies in a periodic pattern or a non-periodic but constant pattern. Can do. If it is confirmed that the change pattern of the periodic displacement amount has been deviated, determine which of the non-periodic change patterns obtained in advance corresponds to the change pattern considered to be the closest. The displacement amount can be predicted by driving.

  Next, steps when performing inspection using the optical film inspection apparatus of the present invention will be described with reference to the flowchart of FIG.

  When the inspection is started (S1), the displacement amount change characteristic data stored in advance is called in the drive amount determination means (11) (S2) and is conveyed by the displacement amount measurement means (4). New displacement amount change characteristic data is acquired from the film (F) (S3). Based on these data, the drive amount or drive pattern of the optical input means (2) is determined in the drive amount determination means (11) (S4). Thereby, the driving of the optical input means (2) is started (S5). Further, the relative distance measuring means (8) obtains the relative distance between the film (F) and the optical input means (2) and sends it to the drive amount determining means (11) (S6). The driving amount determining means (11) calculates the amount of change in the relative distance between the film (F) and the optical input means (2) from this data (S7). At the same time or at an appropriate time interval, data acquisition by the optical input means (2) is started (S8). In the drive amount determination means (11), the relative distance between the film (F) and the optical input means (2) is within a predetermined range from the relative distance between the film (F) and the optical input means (2) and the amount of change. Is verified (S9). If the verification result is out of the predetermined range, the process returns to step S4, the drive amount of the optical input means (2) is recalculated, and the drive amount correction amount is obtained. Based on the correction amount of the driving amount, the optical input means (2) is driven in an appropriate direction in step S5. If the verification result in step S9 is out of the predetermined range, the process returns to step S3 instead of returning to step S4, data is acquired (S3), and the drive amount is recalculated (S4). It may be. If the verification result is within the predetermined range, it is determined that the data captured by the optical input means (2) can be used for processing (S10), and the image processing means (6) uses the optical input means ( The data captured in 2) is processed and saved (S11). In parallel with this process, the possibility that the distance between the film and the optical input means (2) is out of the predetermined range is verified (S12). If it is not likely to deviate, the step of calculating the distance (S6) ), And the steps up to step (S11) for processing and storing the data are repeated. In the verification step (S12), if it is likely to come off, the drive amount or drive pattern of the optical input means (2) is newly corrected (S13), and the optical input means (2) is driven (S14). . Thereafter, the process returns to the step of calculating the distance (S6), and the steps up to the step of processing and storing the data (S11) are repeated. Thus, the continuous optical film (F) that is continuously conveyed is continuously inspected with high accuracy.

  An example of acquiring new displacement change characteristic data from the film being conveyed in the above steps will be described below.

  As shown in Fig. 9 (a), the displacement variation characteristic data shows that the location of the long optical film (F) being transported between the transport rolls (1a) and (1b) varies periodically. It is assumed that the amount of displacement of the inspected portion of the film fluctuates such as G → H 1 → H 2 → H 3 → H 4 → H 5 → H 6 → H 7 → H 8 → G →. The relationship between the amount of film displacement and time is shown in FIG.

  First, the displacement amount of the film is continuously measured for one period or more (preferably 2 to 100 periods), and the maximum value and the minimum value are obtained while measuring. For example, the amount of displacement of a film is measured for a certain period of time, the amount of change in displacement per unit time is calculated from the amount of displacement data, and the point at which the amount of change in displacement is zero is defined as Hmax. The Hmax value is obtained, and the average value is obtained. The average value is similarly obtained for Hmin. Moreover, the time difference between each Hmax or the time difference between each Hmin is calculated | required, Preferably the average value is made into the fluctuation | variation period TF of a film to-be-inspected location. For example, the displacement function of the film being conveyed is expressed as follows.

Y1 = a × cos (2π × T / TF) + b
a = (Hmax−Hmin) / 2
b = (Hmax + Hmin) / 2
In the above, Y1 is a displacement amount, and T is a time (a point at the displacement amount Hmax is zero, and an elapsed time from there). For b, it is preferable to set a reference position (a reference position between the film and the optical input means (2)) at a position where b is 0.

  The optical input means (2) is driven with the same displacement function as the obtained displacement function of the film. When it is difficult to express with mathematical formulas and periodicity is recognized, the optical input means (2) is driven in accordance with the displacement amount change of the film inspection location (T) for one cycle, and the film (F ) And the optical input means (2) may be controlled to be within a predetermined range. Basically, although periodicity is recognized, but irregular fluctuations occur frequently, Hmax, Hmin, TF, maximum drive amount change rate, and minimum drive amount change rate are obtained, and the drive amount is referred to this. Can be determined. That is, the drive amount decreases near Hmax and Hmin, and the drive direction is reversed across zero. After passing through Hmax, it is driven so that the amount of displacement decreases until Hmin. After passing through Hmin, the displacement is driven until Hmax. The drive amount change rate increases up to (TF / 2) time after passing Hmax, and the drive amount change rate decreases after (TF / 2) time.

  According to the flowchart, the optical input means (2) is driven, and the time variation of the position is made to coincide with the displacement amount-time relationship of FIG. 9B as shown in FIG. The difference between the inspection location of the film and the driving position of the optical input means (2) is as shown in FIG. 9 (d), and can be within an allowable fluctuation range.

  If the follow-up of the drive position of the optical input means (2) is delayed with respect to the film displacement, the difference between the inspection location of the film and the drive position of the optical input means (2) is within the allowable fluctuation range. May not fit in. Thus, by measuring the displacement of the long optical film to be inspected continuously or the amount of displacement on the upstream side thereof, the follow-up delay is less likely to occur, and it is possible to ensure that the variation is within the allowable fluctuation range.

  FIG. 10 shows an example of a correction method (by simulation). For example, when the displacement amount of the film being conveyed can be expressed by the above-described equation Y1 = a × cos (2π × T / TF) + b, In the example, a, TF, b are calculated from the actual measurement data of the film inspection location, and the optical input means (2) is driven by the calculation.

  By monitoring the amount of displacement between the optical input means (2) and the film being transported after driving, it can be seen that the center value of the fluctuation is shifted. In the illustrated example, in the initial state indicated by (I), it can be seen that the correction amount of b is known from the deviation of the center value, the fluctuation amount tends to increase, and the TF is shifted. Therefore, first, the value of b is corrected. The correction amount can be determined with reference to the average value of the displacement amount. It can also be seen that in the state of (I), the fluctuation range tends to increase. This means that the actual film fluctuation period and the driving period are deviated with respect to the period TF. Therefore, a value is found that increases or decreases TF to reduce the fluctuation range and make it more constant. By the above correction 1, the state shown in (II) is obtained, and the fluctuation range is reduced. Therefore, in correction 2, TF is further lowered. As a result, the state shown in (III) is obtained, and it can be seen that since the fluctuation range has increased, TF has been lowered too much, and there is an optimum value between correction 1 and correction 2. Therefore, in correction 3, TF is set between correction 1 and correction 2. As a result, the state shown in (IV) is obtained, which is close to the optimum value because the fluctuation range is reduced. Therefore, it can be seen that there is an optimum value between the correction 3 and the correction 1. Therefore, in correction 4, TF is set between correction 1 and correction 3. As a result, the state shown in (V) is obtained, and it can be seen that the TF has reached the optimum value because the fluctuation range is almost constant. However, certain fluctuations still remain. Therefore, in correction 5, a is corrected from the fluctuation range. This results in the state shown in (VI), where a, TF, b match the actual film fluctuation, the correction is performed well, and the optical input means (2) is driven appropriately. I understand. As for the correction of a, since the correction value of a can be found from corrections 2 to 4 and the initial value deviating from zero, the correction can be made there. When changing the driving method, it is preferable to start driving after correction in consideration of the actual film position. For example, in the displacement function (cos equation), it is preferable to start driving with T = 0 when the film reaches the position of Hmax. Sin may be used as the displacement function. In this case, it is preferable to start driving when the inspection location of the film is at the median value of displacement (between Hmax and Hmin).

  In the above-described embodiment shown in FIG. 6, the relative distance measuring means (8) capable of continuously measuring the relative distance between the optical input means (2) and the film and the displacement amount measurement for measuring the displacement of the film. Although provided separately from the means (4), these can also be used as the relative distance measuring means (8). In this case, it is preferable that the displacement amount measuring means (8) for measuring the displacement amount while moving in conjunction with the optical input means (2) can measure the displacement amount with the position fixed. .

FIG. 1 is a perspective view showing a schematic configuration of an inspection apparatus for performing an optical film inspection method according to the present invention. FIG. 2 is a diagram illustrating an example of a conveyance direction (a direction that forms 45 ° with respect to a horizontal plane). FIG. 3 is a diagram illustrating another example (horizontal direction) of the transport direction. FIG. 4 is a diagram illustrating still another example (vertical direction) of the transport direction. FIG. 5 is a diagram illustrating an example of fluttering displacement of the film inspection location in each transport direction. FIG. 6 is a block diagram showing a schematic configuration of the optical film inspection apparatus according to the present invention. FIG. 7 is a view showing an inspection state by the optical film inspection method and inspection apparatus according to the present invention. FIG. 8 is a flowchart showing inspection steps in the optical film inspection method and inspection apparatus according to the present invention. FIG. 9 is a diagram showing effects obtained by the optical film inspection method and inspection apparatus according to the present invention. FIG. 10 is a diagram showing an example of a simulation result of inspection in the optical film inspection method and inspection apparatus according to the present invention.

Explanation of symbols

(2) Optical input means
(4) Displacement measuring means
(10) Drive means
(11) Drive amount determination means
(F) Long optical film
(T) Film inspection location

Claims (10)

In an optical film inspection method for inspecting the film characteristics of a continuous long optical film using an optical input means, the optical input means can be moved, and the film inspection point can be moved from a reference position for inspection. The amount of displacement is measured by the displacement amount measuring means, and the optical input means is driven in accordance with the displacement amount, and the continuously transported long optical film is inspected . When the optical input means is driven, the film inspection location to previously obtain the displacement amount change characteristic for predicting the change in the amount of displacement, an optical film inspection method characterized that you adjust the drive amount of the optical input means in accordance with the displacement amount change characteristic.   2. The optical film inspection method according to claim 1, wherein the driving amount of the optical input means is adjusted so that the distance between the optical input means and the film inspection location falls within a predetermined range. 3. The optical film inspection method according to claim 1 or 2 , wherein the displacement amount change characteristic is determined based on a result of measuring a displacement amount of a portion to be inspected of the long optical film continuously conveyed. The optical film inspection method according to any one of claims 1 to 3 , wherein the displacement amount measuring means measures a displacement amount of the inspection target portion of the long optical film continuously conveyed or an upstream side thereof. . The optical film inspection method according to any one of claims 1 to 4 , wherein a plurality of optical input means and displacement amount measuring means are arranged in the width direction of the long optical film. Met optical film inspection apparatus for performing an optical film inspection method according to claim 1, for measuring a driving means for moving the optical input means, the amount of displacement from the inspection reference position of the film to be inspected portion a displacement amount measuring means, in accordance with the output of the displacement measuring means includes a drive quantity determining means for determining the drive amount of the optical input means, the drive quantity determining means, the amount of displacement change characteristic that has been previously stored with the data is called, the amount of displacement by measuring means, the acquired new displacement variation characteristic data from the film being conveyed optical film inspection apparatus according to claim Rukoto. 7. The optical film inspection apparatus according to claim 6 , wherein the displacement measuring means also serves as a relative distance measuring means for measuring a distance between the optical input means and the film inspection location. Displacement measuring means, the optical film inspection apparatus according to claim 6 or 7, characterized in that it is arranged to be driven simultaneously with the optical input means. The optical film inspection apparatus according to any one of claims 6 to 8 , wherein the displacement amount measuring means measures a displacement amount of a portion to be inspected or the upstream side of the continuously transported long optical film. . The optical film inspection apparatus according to any one of claims 6 to 9 , wherein a plurality of optical input means and displacement amount measuring means are arranged in the width direction of the long optical film.

Images