JP7208684B1 - Optical property measurement system - Google Patents

Abstract

Kind Code: A1 By moving a photometric part at a predetermined distance from the surface of a sample such as a resin film, the sample can be measured at an arbitrary point in the direction of movement, and foreign matter generated along with the movement of the photometric part can be measured. Provided is an optical characteristic measurement system capable of suppressing adhesion to a sample. An optical characteristic measuring system (1) includes a measuring frame (10) arranged at a predetermined distance from the surface of a sample (F), a slider (31) provided reciprocatingly along an extending direction of the measuring frame (10), A slider movement mechanism for slidingly moving the slider 31, and a photometry unit 35 integrally connected to the slider 31 for measuring the measurement light emitted from the sample F are provided. A slider movement space is provided along the extending direction of the measurement frame 10, and the photometry unit 35 moves integrally with the slider 31 moving in the slider movement space. [Selection drawing] Fig. 1

Description

TECHNICAL FIELD The present invention relates to an optical property measuring system for measuring optical properties of a resin film or the like, and more particularly to an optical property measuring system for measuring optical properties of a resin film conveyed on a production line.

Resin films are used in a wide range of fields such as packaging, miscellaneous goods, agriculture, industry, food, medicine, and optics. When the resin film is stretched uniaxially or biaxially or more for the purpose of imparting functionality such as improvement of elastic modulus, improvement of fragility, improvement of water vapor transmission rate, provision of optical anisotropy, etc. There is

In recent years, with the diversification of applications, lighter weight, and higher functionality, stretched films are subject to stringent requirements for moldability and quality, and there are various problems such as breakage during stretching, deterioration in thickness deviation accuracy, and uneven orientation. For example, in the production of an optical film produced by stretching, it is required to precisely control the retardation over a wide area of the film surface. Further, in the production of optical films, it is required to perform high-speed and continuous production in a production line in order to improve the production efficiency. Therefore, it is possible to accurately and quickly measure the retardation of a wide area on the surface of an optical film that is continuously conveyed at high speed in a production line, thereby feeding back the measurement results to the film forming process, and improving the retardation. There is a need for a means of removing non-standard parts from the final product.

Most of the optical property measurement systems for monitoring the retardation of optical films in the production line measure only a specific location in the width direction of the conveyed film, for example, the central portion. An optical property measuring system capable of measuring a plurality of locations in the width direction of a transported film is described, for example, in Japanese Unexamined Patent Application Publication Nos. 2003-100003 and 2004-100002.

The measurement system described in Patent Literature 1 includes a measuring device and a rail for moving the measuring device. The measuring device has a measuring section arranged at the tip of the C-shaped frame. The measurement section consists of a light receiving section and a light projecting section, and is configured to measure the film with the film sandwiched between them. The C-frame can be moved in the width direction of the film by rails installed at the bottom of the frame, and by moving, the width direction profile of the film can be measured.

The measurement system described in Patent Literature 2 is a system whose problem is the generation of foreign matter from a moving device that moves a measuring instrument. The system described in Patent Document 2 includes a conveyer that conveys the film in the conveying path, and a plurality of measurement points that are provided apart in the width direction of the conveying path, and pass through the measurement points at each of the measurement points that are separated in the width direction. A plurality of measuring instruments that measure at a plurality of measuring points on the surface of the film, and at each of the two or more measuring points, two or more of the measuring instruments measure from a plurality of polar angle directions. ,including. A line scan camera or a two-dimensional camera is used as the light receiving element. As a light source, a cold-cathode tube, an optical fiber illumination, a plane emission light source, etc., which can stably emit light of the wavelength required for measurement and can emit light uniformly in the area including the measurement point. of known light sources. As the polarizer, for example, a photonic crystal polarizer having a pattern in which the direction of transmitted polarized light differs for each region is used. That is, the configuration of the measuring instrument is restricted.

JP-A-2001-004535 JP 2016-080473 A

In the apparatus described in Patent Document 1, since the C-frame moves in the width direction of the film by the rails, there is a possibility that foreign matter may be generated when the C-frame moves. If foreign matter adheres to the film, the film becomes defective. In addition, it is necessary to secure a range twice the width of the film as the movable range of the C-frame. That is, the footprint becomes large.

The measurement system described in Patent Literature 2 is a system that solves the problem of the generation of foreign matter from a moving device that moves a measuring instrument. However, as described above, the configuration of the measuring instrument is limited, so the optical properties of the resin film that can be measured are also limited. In principle, all points in the width direction can be measured, but data processing becomes complicated, so measurement is performed only at predetermined measurement points.

The present invention has been made in view of the above points, and its object is to move the photometry unit at a predetermined distance from the surface of the sample, such as a film, so that the sample can be detected at an arbitrary point in the moving direction of the photometry unit. can be measured, and adhesion of foreign matter to a sample caused by the movement of a photometric part can be suppressed.

In order to solve the above problems, an optical property measurement system (1) according to the present invention includes a measurement frame (10) arranged at a predetermined distance from a sample (F), and a partition ( 13) and provided along the extending direction of the measurement frame (10); and the slider travel space (12) provided within the slider travel space (12). A slider (31) reciprocating along the extending direction, a slider movement mechanism (16) for slidingly moving the slider (31), and photometry for measuring the measurement light emitted from the sample (F). and optical system holding means (37) arranged outside the slider moving space (12) and spaced apart from the partition wall (13) for holding the photometry part (35), wherein the The slider (31) in the slider movement space (12) and the photometry section (35) outside the slider movement space (12) are configured to move integrally.

According to the optical characteristic measuring system of the present invention, by moving the photometry unit away from a sample such as a film by a predetermined distance, the sample can be measured at an arbitrary point in the moving direction of the photometry unit, and the photometry unit can be moved. It is possible to suppress the adhesion of foreign matter to the sample, which is generated along with this.

Further, in the optical characteristic measuring system (1) according to the present invention, the partition (13) has a slit-shaped opening (15) provided along the extending direction thereof, and the opening (15) is The slider ( 31 ) and the optical system holding means ( 37 ) may be integrally connected through a gap. With such a structure, the slider moving in the substantially closed slider moving space and the photometric optical system moving outside the slider moving space can be spatially separated with a simple structure, and foreign matter generated from the slider can be separated. effect on the photometric optical system can be suppressed.

Further, in the optical characteristic measuring system (1) according to the present invention, the slider moving mechanism (16) is provided in the slider moving space (12) along its extending direction, and supports the slider (31). In the slider movement space (12), a guide member (14) is provided along the extending direction, and the slider (31 ) may be slidably supported by said guide member (14). With this configuration, it is possible to suppress vibration during movement of the slider, and to suppress blurring of the optical axis of the photometry unit integrally connected to the slider.

Further, the optical property measurement system (1) according to the present invention further comprises a support frame (20) for supporting the measurement frame (10) at a predetermined distance from the sample (F), and the support frame ( 20) includes a duct (23) in fluid communication with the slider movement space (12), and a gas flowing into the duct (23) from the slider movement space (12) to the outside of the slider movement space (12). a vent (22) that can vent to the air. With this configuration, dust generated in the slider movement space (12) can be discharged from the ventilation port (22) without adversely affecting the photometric optical system (36) and the like. Further, by fluidly connecting the vent (22) to an exhaust device or an air purification device provided in the installation environment (for example, a resin film production line) of the optical property measurement system (1), the slider movement space (12) Dust generated inside can be prevented from diffusing to the photometry unit (35) and from diffusing to the installation environment of the optical characteristic measurement system (1).

Further, in the optical property measurement system (1) according to the present invention, the sample (F) is in the form of a film or a plate having a front surface and a back surface, and the measurement frame (10) is the A first measurement frame (10a) spacedly arranged on the front surface side and a second measurement frame (10b) spacedly arranged on the rear surface side of the sample (F), wherein the slider moving space (12) includes a first slider movement space (12a) in said first measurement frame (10a) and a second slider movement space (12b) in said second measurement frame (10b), said slider (31) includes a first slider (31a) that moves within the first slider movement space (12a) and a second slider (31b) that moves within the second slider movement space (12b), The photometry unit (35) includes a light source unit (40) configured to move integrally with the first slider (31a) and emitting measurement light toward the sample (F), and the second slider. (31b) and a light-receiving part (50) configured to move integrally with the sample (F) to receive the measurement light emitted from the sample (F), wherein the slider moving mechanism (16) moves the first The slider (31a) and the second slider (31b) can be moved synchronously. With this configuration, it is possible to perform transmitted light measurement in which the measurement light emitted from the light source unit is transmitted through a film-like or plate-like sample, and the light receiving unit detects the measurement light emitted from the sample.

Further, in the optical characteristic measuring system (1) according to the present invention, the light source unit (40) includes a light source (41), a polarizer (42) into which measurement light from the light source (41) is incident, and the polarized light a photoelastic modulation element (43) on which the measurement light polarized by the element (42) is incident, and the light receiving unit (50) includes an analyzer (51) and photodetectors (52a, 52b). can be configured. With this configuration, the distribution of the optical properties in the sample can be measured at high speed, so that measurement data can be obtained substantially continuously along the trajectory of the movement of the measurement point.

Further, in the optical characteristic measuring system (1) according to the present invention, the light receiving section (50) further comprises a beam splitter (53) for splitting the measurement light emitted from the sample (F) into at least two directions. , the analyzers (51a, 51b) and the photodetectors (52a, 52b) are provided in at least two sets, and each of the measurement lights separated by the beam splitter (53) is divided into separate sets of the incident on the analyzers (51a, 51b) and the photodetectors (52a, 52b), different sets of the analyzers (51a, 51b) being set at different deflection angles. . By configuring in this way, the direction of the orientation axis in the sample can be evaluated.

Further, in the optical characteristic measuring system (1) according to the present invention, the light source section (40) includes the light sources (41P, 41T), the polarizers (42P, 42T), and the photoelastic modulation elements (43P, 43T). ), and the light receiving unit (50) includes the light receiving optical system (36Pb , 36Tb), and one set of the light source optical system (36Pa) and the light receiving optical system (36Pb) is arranged along an orthogonal axis (I ₁ ) orthogonal to the surface of the sample (F). , the light source optical system (36Ta) and the light receiving optical system (36Tb) other than the one set pass through the measurement point (M) where the orthogonal axis (I ₁ ) intersects the surface of the sample (F) and the orthogonal It can be arranged along the axes (I ₂ , I ₃ ) inclined by a predetermined angle (θ) with respect to the axis (I ₁ ). By configuring in this way, three-dimensional optical characteristics can be measured.

Further, in the optical property measuring system (1) according to the present invention, the sample (F) is a long resin film (F) transported by transport means (70), and the measurement frame (10) is , the extending direction of the measuring frame (10) is perpendicular to the conveying direction of the resin film (F), and the resin film (F) has front and back surfaces extending from the measuring frame (10). The resin film (F) is conveyed by the conveying means (70) while being separated by the predetermined distance, and the photometry section (35) reciprocates in the width direction of the resin film (F), which is a direction orthogonal to the conveying direction. can do. By configuring in this way, it is possible to measure the distribution of the optical properties of the long resin film coming out of the production line in the width direction and the transport direction of the film.

According to the optical characteristic measuring system of the present invention, the sample can be measured at an arbitrary point in the moving direction of the photometric unit by moving the photometric unit at a predetermined distance from the surface of the sample such as a film, and the photometric unit can It is possible to suppress adhesion of foreign matter to the sample, which is generated along with the movement of the sample.

1 is an external perspective view of an optical characteristic measurement system as an embodiment of the present invention; FIG. 1 is a front view showing an optical property measurement system; FIG. 1 is a top view of an optical property measurement system; FIG. FIG. 2B is a diagram showing an optical property measurement system, and is a cross-sectional view taken along line AA of FIG. 2(b). FIG. 2 is a diagram showing an optical property measurement system, and is a cross-sectional view taken along line BB of FIG. 2(a). FIG. 2 is a diagram showing an optical property measurement system, and is a cross-sectional view taken along CC in FIG. 2(a). It is a figure which shows an optical characteristic measurement system, and is an enlarged view of the D part of FIG.3(b). FIG. 4 is an explanatory diagram of a specific example of a control unit included in the optical characteristic measurement system; FIG. 3 is an explanatory diagram of a measurement optical system included in the optical characteristic measurement system; FIG. 2 is a diagram showing a configuration in which three measurement optical systems are provided in an optical characteristic measurement system, and is a cross-sectional view at a position corresponding to BB in FIG. 2(a). FIG. 3 is an explanatory diagram of a configuration in which three measurement optical systems are provided in an optical characteristic measurement system; As a modified example of the optical characteristic measuring system, it is a diagram showing a configuration provided with a slider moving mechanism using a feed screw, and is a cross-sectional view at a position corresponding to AA in FIG. 2(b). As a modified example of the optical characteristic measurement system, it is a diagram showing a configuration provided with a slider moving mechanism using a feed screw, and is a cross-sectional view at a position corresponding to BB in FIG. 2(a). As a modified example of the optical characteristic measurement system, it is a diagram showing a configuration including a slider moving mechanism using a timing belt, and is a cross-sectional view at a position corresponding to AA in FIG. 2B. As a modified example of the optical characteristic measurement system, it is a diagram showing a configuration including a slider movement mechanism using a timing belt, and is a cross-sectional view of a position corresponding to BB in FIG. 2(a).

DETAILED DESCRIPTION OF THE INVENTION An optical characteristic measurement system according to an embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an external perspective view of an optical characteristic measurement system as one embodiment of the present invention. 2 and 3 are diagrams showing the optical characteristic measuring system, FIG. 2(a) being a front view and FIG. 2(b) being a top view. 3(a) is a cross-sectional view along AA in FIG. 2(b), FIG. 3(b) is a cross-sectional view along BB in FIG. 2(a), and FIG. 3(c) is a cross-sectional view along FIG. ), and FIG. 3(d) is an enlarged view of the D portion of FIG. 3(b).

As shown in these figures, the optical property measuring system 1 is configured so that it can be suitably used for measuring the distribution of optical properties in the width direction and the conveying direction of a long resin film F to be conveyed. The optical property measurement system 1 comprises a measurement frame 10 , a side frame 20 , a scanning measurement section 30 and a control section 60 . The long resin film F is transported by transport means 70 . The side frames 20 support the measuring frame 10 at both ends of the measuring frame 10 . The scanning measurement unit 30 measures the optical characteristics of the resin film F with the photometry unit 35 while moving in the width direction of the resin film F or while stopped at a predetermined position. The slider moving mechanism 16 moves the slider 31 of the scanning measuring section 30 . The scanning measurement unit 30 moves in the width direction of the resin film F as the slider 31 moves. The slider movement mechanism 16 is a linear motor composed of a mover 32 of the slider 31 and a stator 17 provided on the measurement frame 10 . The control section 60 controls the operation of the scanning measurement section 30 .

The dashed line shown in FIG. 1 indicates the part of the scanning measurement unit 30 that is arranged in the measurement frame 10 . As shown in FIGS. 1 and 2 , the scanning measuring section 30 has a portion disposed within the measuring frame 10 and a portion protruding from the measuring frame 10 toward the resin film F side. A slider 31 is included in the part that is arranged in the measuring frame 10 . The photometry section 35 (the light source section 40 and the light receiving section 50) is mainly included in the portion projecting from the measurement frame 10 toward the resin film F side. 1 to 3 show the configuration for measuring the light transmitted through the resin film F by the scanning measurement unit 30. FIG. That is, the light source side unit 30a of the scanning measurement section 30 is provided on one side of the resin film F, and the light receiving side unit 30b of the scanning measurement section 30 is provided on the other side. Details of the scan measurement unit 30 will be described later.

[Measurement frame]
The measuring frame 10 is arranged so that its extending direction is perpendicular to the direction in which the resin film F is conveyed. Moreover, the measurement frame 10 is arranged at a predetermined distance from the surface of the resin film F. As shown in FIG. The measuring frame 10 is configured to move the scanning measuring section 30 along its extending direction (the width direction of the resin film F).

The measuring frame 10 has a slider moving space 12 in which a slider 31 of the scanning measuring part 30 moves along its extending direction. The slider movement space 12 is a space defined by the partition wall 13 . The partition wall 13 defining the slider moving space 12 is preferably formed so as to surround the slider 31 as much as possible. When the partition wall 13 is formed in this way, it is possible to prevent foreign matter generated by the movement of the slider 31 from scattering out of the slider movement space 12 . As a result, contamination of the resin film F and the photometric optical system 36 (see FIG. 5) by foreign matter generated by the movement of the slider 31 can be suppressed.

The slider moving space 12 is provided with a stator 17 (orbital portion) that supports and moves the slider 31 having the mover 32 along its extending direction. The stator 17 is constructed by alternately arranging a plurality of permanent magnets whose magnetic field directions are opposite to each other in the direction in which the slider movement space 12 extends. Each permanent magnet forming the stator 17 has a concave portion into which the mover 32 of the slider 31 can be fitted. The mover 32 is an electromagnet that can generate an alternating magnetic field by alternating the applied voltage. It is desirable that the stator 17 protrude from the partition wall 13 defining the bottom surface of the slider moving space 12 so as to support the mover 32 provided on the bottom surface of the slider 31 . A power cable for supplying power to the scanning measurement unit 30, such as for applying voltage to the mover 32, and a signal cable for transmitting and receiving signals between the scanning measurement unit 30 and the control unit 60 are connected to the slider. It can be arranged in the movement space 12 .

At least one guide member 14 is provided in the slider moving space 12 along its extending direction. The guide member 14 is laid on the inner surface of the partition wall 13, for example. The guide member 14 is fitted in a concave portion of the slide portion 33 of the slider 31 and slidably supports the slide portion 33 . It is desirable to provide a plurality of guide members 14 so as to support the slider 31 from different directions. In the specific example shown in FIG. 3, two guide members 14 are provided so as to support both sides of a rectangular slider 31 . In this specific example, the slider 31 is slidably supported by fitting a mover 32 provided on the bottom surface thereof into a concave portion of the stator 17 . The slider 31 is slidably supported by guide members 14 having sliding portions 33 provided on both side surfaces thereof fitted in recesses thereof. That is, the slider 31 is reliably supported at three points, the bottom surface and both side surfaces. Therefore, the scanning measurement unit 30 suppresses blurring of the optical axis during scanning.

By configuring the measuring frame 10 as described above, the slider 31 can move (reciprocate) in the slider moving space 12 by the linear motor. By reciprocating the slider 31 in the slider movement space 12 , the scanning measurement unit 30 reciprocates in the extending direction of the measurement frame 10 . Here, the stator 17 is a permanent magnet and the mover 32 is an electromagnet that generates an alternating magnetic field. can also be

As shown in FIGS. 1 to 3, in the present embodiment, the measurement frame 10 includes a first measurement frame 10a arranged above the upper surface of the resin film F at a predetermined distance, and a measurement frame 10a arranged downward from the lower surface of the resin film F. and a second measuring frame 10b spaced a predetermined distance from. Thereby, the scanning measurement unit 30 is configured to measure the transmitted light at a position separated from the resin film F by a predetermined distance. A light source side unit 30a of the scanning measurement section 30 is provided on the first measurement frame 10a arranged on the upper surface side of the resin film F. As shown in FIG. On the other hand, the second measurement frame 10b arranged on the lower surface side of the resin film F is provided with the light receiving side unit 30b of the scanning measurement section 30. As shown in FIG. Although not shown, when the scanning measurement unit 30 is configured to measure the reflected light from the resin film F, the measurement frame 10 includes a light receiving unit for measuring the reflected light from the resin film F. can be provided. This light-receiving unit can be arranged at a predetermined distance from the reflecting surface of the resin film F. As shown in FIG.

[Side frame]
Side frames (support frames) 20 support the measuring frame 10 , for example at both ends of the measuring frame 10 . When the resin film F is conveyed at a predetermined position (photometric level ML) in the longitudinal direction of the side frame 20, the side frame 20 supports the measurement frame 10 so as to be separated from the resin film F by a predetermined distance. The side frame 20 also has a base portion 21 at its lower end (one end). The base portion 21 has an installation surface that abuts on a mounting surface such as a floor surface of a manufacturing line on which the optical characteristic measurement system 1 is mounted. The base portion 21 can be provided with position adjusting means so that the resin film F is transported to the photometric level ML. For example, when the resin film F is horizontally conveyed by the conveying means 70, the position adjusting means is an adjuster that adjusts the height (conveyance level) at which the resin film F is conveyed and the photometry level ML to match. .

The side frame 20 is a hollow tubular body. The base portion 21 has a vent 22 . A hollow portion of the side frame 20 is in fluid communication with the vent 22 and functions as a duct 23 . The duct 23 has an exhaust fan 24 inside it (for example, near or within the base portion 21). The duct 23 is also in fluid communication with the slider travel space 12 of the measurement frame 10 . Therefore, dust generated in the slider moving space 12 can be discharged from the air vent 22 without adversely affecting the photometric optical system 36 (see FIG. 5). Dust generated in the slider moving space 12 can be removed from the optical properties by fluidly connecting the ventilation port 22 to an exhaust device or an air purification device provided in the installation environment of the optical property measurement system 1 (for example, a resin film production line). Diffusion in the installation environment of the measurement system 1 can also be prevented.

As shown in FIG. 3( a ), the side frame 20 has connection terminals 25 . The connection terminal 25 has one end provided inside the side frame 20 and the other end provided outside the side frame 20 . A power cable and a signal cable (not shown) arranged in the slider movement space 12 are connected to one end of the connection terminal 25 through the duct 23 . A connection cable 66 extending from the control unit 60 is connected to the other end of the connection terminal 25 .

As shown in FIG. 2( a ), the lateral frame 20 is provided with a calibration sample holder 27 that supports a calibration sample 26 . Specifically, the calibration sample holder 27 is provided so as to protrude from the side surface of the side frame 20 toward the home position HP. Further, the calibration sample holder 27 is configured so as not to overlap the test area TA through which the resin film F conveyed by the conveying means 70 passes. The calibration sample holder 27 holds the calibration sample 26 so that the photometric optical system 36 (the light source optical system 36a and the light receiving optical system 36b) can measure the calibration sample 26 when the scanning measurement unit 30 is positioned at the home position HP. It supports a part, for example the rim. The calibration sample 26 is measured while the scanning measuring section 30 is waiting for the measurement of the resin film F at the home position HP. The calibration sample 26 is supported by a calibration sample holder 27 so as to be perpendicular to the optical axis of the photometric optical system 36 . It is desirable that the position of the calibration sample 26 is as close as possible to the photometric level ML for measuring the resin film F. In the example shown in FIG. 3, the calibration sample 26 is placed at the photometric level ML for measuring the resin film F. As shown in FIG.

The calibration sample 26 is used to calibrate the photometric optical system 36 included in the scanning measurement section 30 . The calibration sample 26 specifically consists of a zero-order single-plate waveplate or a zero-order double-plate waveplate. A zero-order single-plate wave plate is a wave plate made by processing one sheet of birefringent material (quartz plate, mica plate, etc.) to be extremely thin. A zero-order double-plate waveplate is a waveplate made of a structure in which the crystal axes of two birefringent materials (quartz plate, mica, etc.) that are processed to have a very small phase difference between them are perpendicular to each other. be. The zero-order double-plate waveplate has a structure in which two birefringent materials are perpendicular to each other, so that the amount of phase difference shift that occurs in each material is canceled, so the dependence on the environment such as temperature is suppressed, and the phase difference is uniform. can provide

[Scanning measurement unit]
In the optical property measurement system 1 of this embodiment shown in FIGS. Therefore, the light source side unit 30a of the scanning measurement section 30 is provided on the upper surface side (one side) of the resin film F, and the light receiving side unit 30b of the scanning measurement section 30 is provided on the lower surface side (the other side). Further, the light source side unit 30 a includes the light source section 40 of the photometric section 35 , and the light receiving side unit 30 b includes the light receiving section 50 of the photometric section 35 . The light source side unit 30a and the light receiving side unit 30b of the scanning measurement section 30 are provided with sliders 31a and 31b, respectively. The light source section 40 is integrally connected to the slider 31a, and the light receiving section 50 is integrally connected to the slider 31b. Therefore, the light source unit 40 moves together with the slider 31a along the extending direction of the measurement frame 10a, and the light receiving unit 50 moves together with the slider 31b along the extending direction of the measurement frame 10b.

The sliders 31 (31a, 31b) can move within the slider movement space 12 of the measurement frame 10 (10a, 10b). The slider 31 moves from the home position HP toward the turning-back position RP, and after turning back at the turning-back position RP, moves (reciprocates) toward the home position HP again. The slider 31 has a mover 32 and a concave slide portion 33 . The moving element 32 constitutes a linear motor as the slider moving mechanism 16 together with the stator 17 having a recess provided in the slider moving space 12 . The mover 32 is fitted in a recess of the stator 17 . A guide member 14 provided in the slider moving space 12 is fitted in the slide portion 33 having a concave portion. The slider 31 has its mover 32 slidably supported by the stator 17 . Further, the slider 31 is slidably supported by the guide member 14 at its slide portion 33 . It is desirable to provide a plurality of slide portions 33 so as to support the slider 31 from different directions. The guide members 14 are provided according to the number of slide portions 33 . In the specific example shown in FIG. 3, slide portions 33 are provided on both side surfaces of a rectangular slider 31 and supported by two guide members 14 . The two guide members 14 are laid on the side surfaces of the partition wall 13 that defines the slider movement space 12 . As a result, the slider 31 is reliably supported at three points, the bottom surface and both side surfaces. Therefore, the scanning measurement unit 30 suppresses blurring of the optical axis during scanning. Also, the slider 31 is separated from the inner surface of the partition wall 13 except for the two slide portions 33 . Therefore, dust generation due to sliding of the slider 31 is suppressed.

The light source side unit 30a includes an optical system holding means 37a. The optical system holding means 37a holds a light source section 40 having a light source optical system 36a that constitutes the light source side of the photometric optical system 36. As shown in FIG. Also, the optical system holding means 37 a has a connecting portion 38 that connects to the slider 31 . The light-receiving side unit 30b includes an optical system holding means 37b. The optical system holding means 37b holds a light receiving section 50 having a light receiving optical system 36b that constitutes the light receiving side of the photometric optical system 36. As shown in FIG. Further, the optical system holding means 37b has a connecting portion 38 connected to the slider 31. As shown in FIG. Here, the optical system holding means 37 (37a, 37b) will be explained, and the photometric optical system 36 will be explained later.

The partition wall 13 has a slit-shaped opening (gap) 15 provided along the extending direction of the slider movement space 12 . The upper portion of the slider 31a of the light source side unit 30a (the upper portion of the side wall of the slider 31 in the figure) is arranged to pass through the opening 15, as shown in the enlarged view of FIG. 3(d). The slider 31 is connected to the connecting portion 38 of the optical system holding means 37a by the upper portion of the slider 31a passing through the opening 15. As shown in FIG. On the other hand, the lower part of the slider 31b of the light receiving unit 30b (the lower part of the side wall of the slider 31 in the figure) is arranged so as to pass through the opening 15 . The lower portion of the slider 31b passing through the opening 15 connects the slider 31b to the connecting portion 38 of the optical system holding means 37b. The width of the opening 15 is slightly larger than the thickness of the sidewalls of the sliders 31 (31a, 31b) passing through. Therefore, the optical system holding means 37 can move integrally with the slider 31 . Here, there is a possibility that foreign matter generated by movement of the slider 31 may be generated in the slider moving space 12 . Foreign matter may contaminate the photometry section 35 (the light source section 40 and the light receiving section 50). Therefore, in order to prevent foreign matter from scattering outside the slider moving space 12, the partition wall 13 is formed to surround the slider 31 except for the opening 15. As shown in FIG. Also, the opening 15 is provided at a position far from the photometry section 35 . The slider moving space 12 is fluidly connected to a duct 23 provided with an exhaust fan 24 . By fluidly connecting the air vent 22 at the end of the duct 23 to an exhaust device or an air purification device provided in the installation environment of the optical property measurement system 1 (for example, the production line of the resin film F), the inside of the slider moving space 12 The dust generated in is prevented from diffusing into the photometric optical system 36 and into the installation environment of the optical characteristic measuring system 1 .

As shown in FIGS. 3(b) and 3(d), the optical system holding means 37 is configured to surround the outer peripheral surface of the partition wall 13. As shown in FIG. Further, the optical system holding means 37 is supported by the slider 31 supported by the guide member 14 on the inner peripheral surface of the partition wall 13 . A predetermined gap is provided between the optical system holding means 37 and the outer surface of the partition wall 13 . That is, the optical system holding means 37 can move on the outer peripheral surface of the partition wall 13 along the extending direction of the measurement frame in a substantially non-contact state.

As shown in FIGS. 3(a) and 3(b), the light source unit 40 and the light receiving unit 50 held by the optical system holding means 37 are arranged such that the slider movement space 12 and the photometric level ML through which the resin film F passes. placed in between. The light source unit 40 and the light receiving unit 50 are provided with supports (not shown) for supporting the optical elements constituting the photometric optical system 36 (the light source optical system 36a and the light receiving optical system 36b) at predetermined positions and postures. . This support can have a mechanism for adjusting the positional relationship of the optical elements. The light source section 40 and the light receiving section 50 have a window section 39 on the surface facing the photometry level ML. The window part 39 is configured by a plate material (for example, a quartz plate) or an opening made of a material through which the measurement light can pass. The light source unit 40 and the light receiving unit 50 can be surrounded by a light shielding material so that the portions other than the window 39 are shielded from light.

[Control part]
FIG. 4 is a block diagram showing a schematic configuration of a controller included in the optical property measurement system 1. As shown in FIG. A control unit 60 shown in the figure is composed of a personal computer (PC) or the like. The control unit 60 includes a main control unit 61 such as a CPU, a display unit 62 having a display device such as a display, a storage device 63 such as a nonvolatile memory, an input device 64 such as a mouse and a keyboard, and an interface. It is mainly composed of a unit 65 . When the control unit 60 is a PC, the controlled elements included in the optical characteristic measurement system 1, specifically, the motor controller 83 for controlling the slider moving mechanism 16 for moving the slider 31 shown in FIG. 5, and the light source optical system 36a. A PEM controller 81 for controlling the photoelastic modulation element (PEM) 43 and a control program for causing the PC to function as a control unit for the lock-in amplifier 82 are installed in the PC. The control program operates the controlled elements based on the operating parameters of the optical property measurement system 1 input from the input device 64 . The control program also controls the state of the optical characteristic measurement system 1, for example, the positions of the light source side unit 30a and the light receiving side unit 30b of the scanning measurement section 30 on the measurement frame 10, the slider moving mechanism 16 and the photometric optical system 36 (light source Acquisition of outputs from various sensors (not shown) provided for monitoring the operation state of the optical system 36a and the light receiving optical system 36b) and the transport state of the resin film F in the vicinity of the measurement frame 10, and the output is displayed on the display unit 62, and feedback control or feedforward control of the controlled element is performed by the output. In addition, an analysis program is installed in the PC to acquire the output of the photometric optical system 36 and to make the PC function as a data analysis section. The analysis program acquires the output of the photodetector 52 (52a, 52b) of the light receiving optical system 36b shown in FIG. The output of the device 52 is analyzed, and the analysis result is displayed on the display unit 62 and stored in the storage device 63 .

[Conveyance Means]
The optical property measurement system 1 can be configured to measure the optical properties of a length of resin film F coming out of a production line, as shown in FIG. As the conveying means 70 for conveying the long resin film F, one provided in the production line can be used. That is, the optical property measurement system 1 can be arranged across the conveying means 70 that conveys the resin film F while keeping it flat. A sensor (for example, a camera) for monitoring the transport state of the resin film F near the optical property measuring system 1 is provided in the optical property measuring system 1, and the light source side unit 30a and the light receiving unit 30a of the scanning measurement unit 30 are operated based on the output of the sensor. It is also possible to control the side unit 30b. It is also possible for the optical property measuring system 1 to control part of the conveying means 70 , for example the part before and after the optical property measuring system 1 . Such modifications will be described later.

[Photometric optical system]
As a preferred specific example of the photometric optical system 36, a configuration for birefringence phase difference measurement by photoelastic modulation will be described with reference to FIGS. 3 and 5. FIG. The photometry section 35 includes a light source section 40 provided in the light source side unit 30a and a light receiving section 50 provided in the light receiving side unit 30b. The photometric optical system 36 includes a light source optical system 36 a provided in the light source section 40 and a light receiving optical system 36 b provided in the light receiving section 50 .

In the light source optical system 36a, a light source 41, a polarizer unit 42, and a photoelastic modulation element (PEM) 43 are arranged in this order from the distal side of the resin film F. As shown in FIG. The light receiving optical system 36b has an analyzer unit 51 (51a, 51b) and a photodetector 52 (52a, 52b) arranged in this order along the incident direction of the measurement light. The light receiving optical system 36b can further include a beam splitter 53 as in the specific examples shown in FIGS. Also, the light receiving optical system 36b can further include an optical filter for removing the influence of ambient light.

The light source 41 is selected according to the optical properties to be measured, for example, a helium-neon laser (wavelength: 543.5 nm, 594.1 nm, or 632.8 nm), an LED light source (wavelength: 405 nm, 450 nm, 590 nm, or 640 nm ), or a semiconductor laser (wavelength: 405 nm, 450 nm, 520 nm, or 637 nm). As shown in FIG. 7, which will be described later, when a plurality of photometric optical systems 36P and 36T are provided, the light sources 41P and 41T of the respective photometric optical systems emit light from a single light source device even if they are composed of separate light source devices. The light may be split by a beam splitter, an optical fiber, or the like.

Light emitted from the light source 41 is linearly polarized by a polarizer (for example, a Glan-Thompson prism) of the polarizer unit 42 . The polarizer unit 42 is arranged such that the polarization direction is at a predetermined angle (eg +45°) with respect to the reference axis.

The light linearly polarized by the polarizer unit 42 enters the PEM 43 . PEM 43 is positioned at 0° with respect to the reference axis. The PEM 43 is controlled by applying, for example, an alternating electric field of 50 kHz from the PEM controller 81 as a modulating signal. The PEM controller 81 refers to the reference signal R emitted from the lock-in amplifier 82 connected to the preamplifier 84 of the photodetector 52 and emits the modulated signal. The PEM 43 modulates the incident light into measurement light that continuously changes over time from circularly polarized light to linearly polarized light. It is also possible to configure the lock-in amplifier 82 to synchronously detect the modulation signal of the PEM controller 81 as a reference signal.

The measurement light is incident on the measurement point M of the resin film F and passes through the resin film F in the thickness direction. The resin film F causes the measuring light to have a birefringent phase difference corresponding to the distortion and molecular orientation at the position (measurement point M) through which the measuring light passes. The measurement light with the birefringence phase difference is incident on the light receiving section 50 .

In the specific example shown in FIGS. 3 and 5, the light receiving section 50 includes a beam splitter 53, and a plurality of sets of analyzer units 51a and 51b and photodetectors 52a and 52b. The measurement light that has passed through the measurement point M of the resin film F and has a birefringence phase difference is incident on the beam splitter 53 . The measurement light incident on the beam splitter 53 is separated into light traveling straight through the beam splitter 53 (straight advancing light) and light reflected inside the beam splitter 53 (reflected light). The reflected light is directed in a direction perpendicular to the traveling direction of straight light.

The analyzers of the analyzer units 51a and 51b are, for example, Glan-Thompson prisms. When the polarizer of the polarizer unit 42 is arranged in the polarization direction of +45° with respect to the reference axis, the analyzer unit 51a on which the rectilinear component is incident has the polarization direction of −45° with respect to the reference axis. placed. On the other hand, the analyzer unit 51b into which the reflected component is incident is arranged so that the polarization direction is 0 degree from the reference axis. Therefore, the straight light that has passed through the analyzer unit 51a is incident on the photodetector 52a with a polarization component of −45° from the reference axis. On the other hand, in the reflected light that has passed through the analyzer unit 51b, the polarization component at 0° from the reference axis enters the photodetector 52b.

The -45° and 0° polarization components are converted to photocurrents at photodetectors 52a and 52b, respectively. The photodetectors 52a and 52b are, for example, photodiodes or photomultiplier tubes. The converted photocurrent is sequentially input to a preamplifier 84 connected to the photodetectors 52a and 52b and a lock-in amplifier 82 connected to the preamplifier 84 and amplified. The output of the lock-in amplifier 82 is taken into the PC as the control unit 60 via the interface unit 65 (A/D converter) of the PC. The PC analyzes the captured output data using a predetermined analysis program installed. The PC outputs the birefringence phase difference and the direction of the orientation axis at the measurement point M as the result of data analysis. The PC stores data and analysis results in the storage device 63

The light receiving section 50 can also be configured with only one set of the analyzer unit 51a and the photodetector 52a. With such a configuration, only the birefringence phase difference is obtained as an analysis result. For example, when the polarizer of the polarizer unit 42 is arranged in a polarization direction of +45° with respect to the reference axis, the analyzer unit 51a is arranged such that the polarization direction is -45° from the reference axis. .

The birefringence phase difference measurement method using photoelastic modulation can measure the birefringence phase difference at high speed and with high sensitivity. When the resin film F moves at a transport speed (up to 500 m/min) in the production line, the amount of movement of the measurement point M during the time required for measurement of each measurement point M is very small. Therefore, it is possible to continuously measure the surface direction of the resin film F conveyed in the production line. When the optical characteristic measurement system 1 is installed downstream of the resin film F manufacturing apparatus, the measurement point M by the photometric optical system 36 of the scanning measurement unit 30 that scans the resin film F in the width direction is on the resin film F. move in a zigzag pattern. It is also possible to preset the measurement positions in the width direction of the resin film F and measure only the set measurement positions.

[Modification]
The optical property measurement system of the above embodiment can be modified for simplification or sophistication. Simplification or sophistication variants are described below.

<Structure capable of measuring three-dimensional optical properties of resin film F>
FIG. 6 is a diagram showing a configuration in which three measurement optical systems are provided in an optical characteristic measurement system according to an embodiment of the present invention, and is a cross-sectional view of a position corresponding to BB in FIG. 2(a). Also, FIG. 7 is an explanatory diagram of a configuration in which three measurement optical systems are provided. As shown in these figures, the light source unit 40 can include a light source optical system 36Pa and a light source optical system 36Ta. Further, the light receiving section 50 can include a light receiving optical system 36Pb and a light receiving optical system 36Tb. The light source optical system 36Pa and the light receiving optical system 36Pb constitute _a vertical photometric optical system having an optical axis I1 in a direction orthogonal to the resin film F being conveyed. The light source optical system 36Ta and the light receiving optical system 36Tb constitute an oblique photometric optical system in which the optical axes _I2 and _I3 are inclined at a predetermined angle θ from the orthogonal directions. Although one tilt photometric optical system 36T may be provided, as shown in FIGS. 6 and 7, it is desirable to provide _two symmetrical with respect to the optical axis I1 of the vertical photometric optical system 36P. The optical property measuring system 1 can measure the three-dimensional optical properties of the resin film F by including a vertical photometric optical system and at least one oblique photometric optical system. The calibration samples 26 are provided for each of the optical axis I ₁ , the optical axis I ₂ and the optical axis I ₃ . Each calibration sample 26 is supported by a calibration sample holder 27 so as to be orthogonal to each optical axis (I ₁ , I ₂ , I ₃ ). In the example shown in FIG. 6, the calibration sample holder 27 is arranged closer to the light source unit 40 than the photometric level ML for measuring the resin film F. In the example shown in FIG.

The vertical measurement optical system may tilt the optical axis I1 as long as the tilt angle is ₅ ° or less. The tilt angle θ of the optical axes I ₂ and I ₃ of the tilt photometric optical system is 20° to 50°, preferably 40°±5°. With this configuration, the three-dimensional optical properties of the resin film F can be measured more accurately.

Each light receiving optical system 36Pb and 36Tb can be configured to include a beam splitter and a plurality of sets of analyzer units and photodetectors, similar to the light receiving optical system 36b shown in FIG. With such a configuration, the three-dimensional optical properties of the resin film F are the birefringence phase difference and the direction of the orientation axis.

<Structure of Slider Moving Mechanism Using Feed Screw>
The optical characteristic measurement system 1 can adopt a configuration using a feed screw as the slider movement mechanism instead of the configuration of the linear motor shown in FIG. 3 and the like. 8A and 8B are diagrams showing a configuration including a slider movement mechanism using a feed screw, FIG. 8A is a cross-sectional view of a position corresponding to AA in FIG. FIG. 3 is a cross-sectional view at a position corresponding to BB in FIG. 2(a); In FIG. 8, the configuration other than the slider 31 is the same as that of the optical characteristic measurement system 1 that employs the configuration of the linear motor, so the explanation is omitted.

A slider movement mechanism using a feed screw includes a cylindrical male screw 91 , a block-shaped female screw portion 92 , a rotary motor 93 that rotates the male screw 91 , and a bearing 94 . A cylindrical male screw 91 is provided in the slider moving space 12 along its extending direction as a track portion for supporting and moving the slider 31 . A rotary motor 93 (for example, a servo motor or a stepping motor) is connected to one end of the male screw 91 to rotate the male screw 91 . The rotary motor 93 is connected to the motor controller 83 (see FIG. 4). The other end of the male screw 91 is supported by a bearing 94 . The slider 31 has a block-shaped female screw portion 92 for receiving the driving force transmitted by the male screw 91 . The control unit 60 controls movement of the scanning photometry unit 30 having the slider 31 by transmitting a control signal for controlling the rotation motor 93 to the motor controller 83 .

A guide member 14 provided in the slider movement space 12 is fitted in the slide portion 33 having a recess. The slide portion 33 is slidably supported by the guide member 14 so that the slider 31 does not rotate around the male screw 91 . It is desirable to provide a plurality of slide portions 33 so as to support the slider 31 from different directions. In the specific example shown in FIG. 8, two slides 33 are provided on both sides of a rectangular slider 31 and supported by two guide members 14 . The slider 31 is supported by a male screw 91 at its central portion.

<Structure of Slider Moving Mechanism Using Timing Belt>
The optical characteristic measurement system 1 can employ a configuration using a timing belt as the slider movement mechanism instead of the configuration of the linear motor shown in FIG. 3 and the like. 9A and 9B are diagrams showing a configuration having a slider movement mechanism using a timing belt, FIG. 9A is a cross-sectional view of a position corresponding to AA in FIG. FIG. 3 is a cross-sectional view at a position corresponding to BB in FIG. 2(a); In FIG. 9, the configuration other than the slider 31 is the same as that of the optical characteristic measurement system 1 that employs the configuration of the linear motor, so the explanation is omitted.

The timing belt slider movement mechanism includes a rotary motor 93 , a timing belt 96 , a driving pulley 97 and a driven pulley 98 . The timing belt 96 is provided in the slider moving space 12 along the direction in which the slider 31 extends as a track portion that supports and moves the slider 31 . The slider 31 has its bottom fixed to the timing belt 96 . A timing belt 96 is looped around a drive pulley 97 and a driven pulley 98 . A rotary motor 93 (eg, a servomotor or stepper motor) rotates a drive pulley 97 . The rotary motor 93 is connected to the motor controller 83 . The control unit 60 controls movement of the scanning/measuring unit 30 having the slider 31 by transmitting a control signal for controlling the rotation motor 93 to the motor controller 83 .

A guide member 14 provided in the slider movement space 12 is fitted in the slide portion 33 having a recess. The slide portion 33 is slidably supported by the guide member 14 . It is desirable to provide a plurality of slide portions 33 so as to support the slider 31 from different directions. In the specific example shown in FIG. 9, two slide portions 33 are provided on both sides of a rectangular slider 31 and supported by two guide members 14 .
<Modified Example of Conveying Means>

The optical property measuring system 1 may also control part of the transport means 70 , for example the front and rear parts of the optical property measuring system 1 . In this case, the conveying means 70 controlled by the optical property measuring system 1 is preferably provided with a tension adjusting device for adjusting the tension of the resin film F and a buffer section for retaining the resin film F. By configuring in this way, the resin film F can be conveyed at an optimal speed for measurement by the optical property measurement system 1 . Further, by intermittently transporting the resin film F to the optical property measurement system 1, it is possible to measure the resin film F while the transport of the resin film F is stopped.

The optical property measurement system 1 can also be configured to detect the edges in the width direction of the resin film F being transported or the marks provided on the resin film F. FIG. Then, it is possible to correct the positional information of the measurement point M on the resin film F based on the detection results of these edges and the like. Further, the optical property measurement system 1 may be provided with means for mechanically or pneumatically adjusting the conveying direction of the resin film F with respect to the measurement frame 10 .

The optical property measurement system 1 can also be configured to support the resin film F from the lower surface side by an air floating mechanism or the like so that the resin film F that is conveyed passes through the measurement frame 10 while maintaining a flat state. .

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the technical ideas described in the claims, the specification and the drawings. Deformation is possible.

REFERENCE SIGNS LIST 1 optical property measurement system 10 measurement frame 10a first measurement frame 10b second measurement frame 12 slider moving space 13 partition 14 guide member 15 opening 16 slider moving mechanism 17 stator (trajectory)
20 side frame (support frame)
21 base part 22 vent 23 duct 24 exhaust fan 26 calibration sample 27 calibration sample holder 30 scanning measurement part 30a light source side unit 30b light receiving side unit 31, 31a, 31b slider 32 mover 33 slide part 35 photometry part 36 (36P, 36T ) Photometric optical system 36a, 36Pa, 36Ta Light source optical system 36b, 36Pb, 36Tb Light receiving optical system 37, 37a, 37b Optical system holding means 38 Connection part 39 Window part 40 Light source part 41, 41P, 41T Light source 42, 42P, 42T Polarized light child unit (polarizer)
43, 43P, 43T Photoelastic modulation element (PEM)
50 light receiving part 51, 51P, 51T, 51a, 51b analyzer unit (analyzer)
52, 52P, 52T, 52a, 52b Photodetector 53 Beam splitter 60 Control unit 61 Main control unit 62 Display unit 63 Storage device 64 Input device 65 Interface unit 66 Connection cable 70 Conveying means 81 PEM controller 82 Lock-in amplifier 83 Motor Controller 84 Preamplifier 91 Male screw (race)
92 Internal screw portion 93 Rotary motor 94 Bearing 96 Timing belt (orbit)
97 Drive pulley 98 Driven pulley F Resin film I1, _{I2 , I3} Optical axis/axis line HP Home position M Measurement point ML Photometry level R Reference signal RP Return position TA Test area

Claims (9)

a measurement frame positioned at a predetermined distance from the sample;
a slider movement space defined by a hollow columnar partition within the measurement frame and provided along an extending direction of the measurement frame;
a slider provided in the slider movement space and capable of reciprocating along the extending direction of the slider movement space;
a slider movement mechanism that slides the slider;
a photometry unit for measuring measurement light emitted from the sample;
an optical system holding means arranged apart from the partition outside the slider movement space and holding the photometry unit;
The slider movement mechanism is provided in the slider movement space along the extension direction thereof, and has a track portion for supporting and moving the slider,
The slider movement space is sealed by the partition on a side closer to the sample than the track portion,
An optical characteristic measuring system, wherein the slider within the slider movement space and the photometry unit outside the slider movement space move integrally. The partition has a slit-shaped opening provided along its extending direction,
2. An optical characteristic measuring system according to claim 1, wherein said slider and said optical system holding means are integrally connected through said opening. A guide member is provided along the extension direction in the slider moving space,
2. The optical characteristic measuring system according to claim 1, wherein said slider is slidably supported by said guide member. further comprising a support frame for supporting the measurement frame at a predetermined distance from the sample;
The support frame has a duct that fluidly communicates with the slider movement space, and an air vent that can discharge gas flowing from the slider movement space into the duct to the outside of the slider movement space. The optical property measurement system according to claim 1. a measurement frame positioned at a predetermined distance from the sample;
a slider moving space defined by a partition within the measuring frame and provided along an extending direction of the measuring frame;
a slider provided in the slider movement space and capable of reciprocating along the extending direction of the slider movement space;
a slider movement mechanism that slides the slider;
a photometry unit for measuring measurement light emitted from the sample;
an optical system holding means arranged apart from the partition outside the slider movement space and holding the photometry unit;
The slider in the slider movement space and the photometry unit outside the slider movement space are configured to move integrally,
The sample is in the form of a film or plate having a front surface and a back surface,
The measurement frame includes a first measurement frame spaced apart on the front side of the sample and a second measurement frame spaced on the back side of the sample,
the slider movement space includes a first slider movement space within the first measurement frame and a second slider movement space within the second measurement frame;
the slider includes a first slider that moves within the first slider movement space and a second slider that moves within the second slider movement space;
The photometry unit includes a light source unit configured to move integrally with the first slider and emitting measurement light toward the sample, and a light source unit configured to move integrally with the second slider. a light receiving unit that receives measurement light emitted from the sample,
The optical characteristic measuring system, wherein the slider movement mechanism synchronously moves the first slider and the second slider. The light source unit includes a light source, a polarizer on which measurement light from the light source is incident, and a photoelastic modulation element on which the measurement light polarized by the polarizer is incident,
6. The optical characteristic measuring system according to claim 5, wherein the light receiving unit comprises an analyzer and a photodetector. The light receiving unit further comprises a beam splitter that splits the measurement light emitted from the sample into at least two directions,
At least two sets of the analyzer and the photodetector are provided,
each of the measurement beams separated by the beam splitter is incident on a separate set of the analyzer and the photodetector;
7. The optical property measurement system of claim 6, wherein different sets of said analyzers are set at different deflection angles. The light source unit includes at least two sets of light source optical systems having the light source, the polarizer, and the photoelastic modulation element,
The light receiving unit includes at least two sets of light receiving optical systems having the analyzer and the photodetector,
A set of the light source optical system and the light receiving optical system are arranged along an orthogonal axis orthogonal to the surface of the sample,
The light source optical system and the light receiving optical system other than the one set are arranged along an axis that passes through a measurement point where the orthogonal axis intersects the surface of the sample and is inclined at a predetermined angle with respect to the orthogonal axis. 7. An optical property measurement system according to claim 6. The sample is a long resin film transported by transport means,
the measuring frame is arranged such that the extending direction of the measuring frame is orthogonal to the conveying direction of the resin film;
The resin film is conveyed by the conveying means in a state in which the front surface and the back surface thereof are separated from the measurement frame by the predetermined distance,
6. The optical characteristic measuring system according to claim 1, wherein the photometric unit reciprocates in a width direction of the resin film, which is a direction orthogonal to the conveying direction.

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