CN218726749U

CN218726749U - Film polarization defect detection device

Info

Publication number: CN218726749U
Application number: CN202222608476.6U
Authority: CN
Inventors: 董庆荣; 陈凤军; 范辉; 屠鑫
Original assignee: Zhejiang Jiemei Electronic and Technology Co Ltd
Current assignee: Zhejiang Jiemei Electronic and Technology Co Ltd
Priority date: 2022-09-30
Filing date: 2022-09-30
Publication date: 2023-03-24
Anticipated expiration: 2032-09-30

Abstract

A film polarization defect detection apparatus, comprising: a light source illuminating the film at one side thereof; a first polarizing filter disposed between the light source and the film; a second polarization filter disposed opposite to the first polarization filter and on the other side of the film; a camera provided on a side of the second polarizing filter remote from the film, the camera receiving transmitted light irradiated from the light source and transmitted through the first polarizing filter, the film, and the second polarizing filter; the first polarized light filter and the second polarized light filter are respectively provided with an angle adjusting mechanism; the first polarized filter and the second polarized filter can realize angle adjustment in a range of 360 degrees with the precision of <0.1 degrees in respective planes through respective corresponding angle adjusting mechanisms. The utility model discloses, not only be applicable to the undulant little membrane of alignment angle, also can the accurate polarisation defect that detects out the undulant great membrane of alignment angle.

Description

Film polarization defect detection device

Technical Field

The utility model relates to a membrane polarisation defect detection device belongs to the defect inspection field of membrane.

Background

The general production process flow of the film comprises the processes of chip melting, filtering, extruding and stretching, and when some impurities and unsintered materials in the processes of chip melting and filtering are not processed cleanly, crystal points are formed in the inner part or the surface of the finished film. The inspection of the defects of the crystal point, the insoluble substance and the like by the polarized light is generally carried out by an automatic inspector by the cross nicol method.

The cross nicol method is a method in which the orientation major axes of two polarizing plates are made to be orthogonal to each other to form a dark field, and an object to be measured such as a film is sandwiched between the two polarizing plates, and observation is performed under transmitted light. With the cross nicol arrangement, if no defect is present, a completely black image is input from the imaging unit, and if a defect is present, the portion is not blackened. That is, since the film is expressed as a bright point when foreign matter or defect exists, defect inspection can be performed.

The cross nicol method is suitable for detecting a film polarization defect with an orientation angle of 0 °, but the orientation angle of the film is caused by orientation during the stretching of the film, and an image inputted from the image pickup unit is affected by the orientation angle, so that an accurate detection effect cannot be achieved.

As for the inspection of the polarizing defect of the above-mentioned film, as disclosed in publication No. CN102906561A, a film defect inspection apparatus is disclosed, which is an inspection apparatus for inspecting a defect of a long film, and is characterized in that the inspection apparatus comprises: an illumination mechanism for illuminating the film on one surface side of the film; a 1 st polarizing plate provided between the illumination means and the film; a 2 nd polarizing plate provided on the other surface side of the film; and a light receiving means provided on the other surface side of the film and receiving transmitted light which is irradiated from the illuminating means and transmitted through the 1 st polarizing plate, the film, and the 2 nd polarizing plate, wherein the detecting device includes angle adjusting means for adjusting an angle of the 1 st polarizing plate in a plane of the 1 st polarizing plate and an angle of the 2 nd polarizing plate in a plane of the 2 nd polarizing plate individually.

The angle adjusting mechanism of the film defect detecting device comprises a shaft which acts as a fulcrum when the first polarizing filter rotates, and a direct-acting mechanism which pushes and pulls the polarizing filter in a rotating direction approximately by taking the end of the first polarizing filter as a force application point, wherein the push-pull distance of the direct-acting mechanism and the rotating angle of the polarizing filter can only reach a fixed proportional relation in a small range, and can not have good precision when adjusting a large angle, so that the angle of the 1 st polarizing filter and the 2 nd polarizing filter can only be adjusted in a precision of below 1 DEG within a range of-8 to 8 DEG, only a film with small change of an alignment angle can be applied, and a film with large fluctuation of the alignment angle can not achieve good polarized defect detection.

SUMMERY OF THE UTILITY MODEL

To prior art's weak point, the utility model provides a membrane polarisation defect detecting device not only is applicable to the undulant little membrane of alignment angle, also can accurately detect out the polarisation defect of the undulant great membrane of alignment angle.

A film polarization defect detection apparatus, comprising:

a light source illuminating the film at one side thereof;

a first polarizing filter disposed between the light source and the film;

a second polarization filter disposed opposite to the first polarization filter and on the other side of the film;

a camera provided on a side of the second polarizing filter remote from the film, the camera receiving transmitted light irradiated from the light source and transmitted through the first polarizing filter, the film, and the second polarizing filter;

the first polarized light filter and the second polarized light filter are respectively provided with an angle adjusting mechanism;

the first polarized filter and the second polarized filter can realize angle adjustment in a range of 360 degrees with the precision of <0.1 degrees in respective planes through respective corresponding angle adjusting mechanisms.

According to the technical scheme, the angle adjusting mechanism is adopted, so that the first polarized light filter and the second polarized light filter can realize angle adjustment within the range of 360 degrees in the respective plane with the precision of <0.1 degree, and the method is suitable for detecting the polarized light defects of the film with small alignment angle fluctuation and the film with large alignment angle fluctuation.

Preferably, the light source, the first polarizing filter, the second polarizing filter, and the camera constitute an inspection unit group, the inspection device includes a plurality of inspection unit groups arranged in a width direction of the film, and the angle adjustment mechanism is arranged in each of the first polarizing filter and the second polarizing filter of each inspection unit group so that the first polarizing filter and the second polarizing filter can be angularly adjusted within a range of 360 ° with an accuracy of <0.1 ° in each plane.

Preferably, the angle adjusting mechanism includes a fixing portion to which the polarization filter is fixed at an inner ring and which can rotate the polarization filter in a plane in which the polarization filter is located, and a driving portion which drives the fixing portion to rotate.

Preferably, the fixing part and the driving part are both belt wheel structures and are connected through a synchronous belt.

Preferably, the fixing part and the driving part are both gear structures, and both gear structures form a gear transmission structure.

Preferably, the driving part is driven by a stepping motor or a servo motor.

Preferably, the diameter of the driving portion is smaller than the diameter of the fixing portion.

Preferably, the angle adjustment mechanism of the first polarization filter has a ratio of the diameter of the driving part to the fixed part > 1; the ratio of the diameter of the driving part to the fixed part of the angle adjusting mechanism of the second polarization filter is not more than 1.

Preferably, the plurality of inspection cell groups are arranged in a staggered manner in the width direction of the film.

Preferably, the first polarization filter and the second polarization filter are both circular polarization filters.

To sum up, the utility model discloses following beneficial effect has:

1: the utility model discloses, adopt angle adjustment mechanism, make first polarisation filter and second polarisation filter realize carrying out angular adjustment in order <0.1 precision in 360 within ranges separately in the face, not only be applicable to the undulant little membrane of alignment angle, also be applicable to the polarisation defect detecting of the undulant big membrane of alignment angle.

2: the utility model discloses, regard as 1 group's device with light source, first polarisation filter, second polarisation filter and camera, make the multiunit device dislocation configuration on the width direction of membrane, prevent that two adjacent light sources from shining the projected overlap part on the membrane to producing the influence to detecting the precision, promote detection effect.

Drawings

FIG. 1 is a layout view of a film polarization defect inspection apparatus;

FIG. 2 is a diagram of the arrangement of membranes;

fig. 3 is a connection diagram of the angle adjustment mechanism.

Detailed Description

The present invention will be further explained by the following embodiments with reference to the attached drawings.

Example (b): as shown in fig. 1 to 3, a film polarization defect detecting apparatus includes:

a light source 2 that irradiates the film 1 on one side of the film 1;

a first polarizing filter 3-1 disposed between the light source 2 and the film 1;

a second polarization filter 3-2 disposed opposite to the first polarization filter 3-1 and on the other side of the film 1;

a camera 4 disposed on a side of the second polarization filter 3-2 remote from the film 1, and receiving transmitted light irradiated from the light source 2 and transmitted through the first polarization filter 3-1, the film 1, and the second polarization filter 3-2;

the first polarized light filter 3-1 and the second polarized light filter 3-2 are respectively provided with an angle adjusting mechanism;

the center positions of the light source 2, the first polarizing filter 3-1, the second polarizing filter 3-2, and the camera 4 are on a line perpendicular to the film 1.

What is different from the prior art is that, in this embodiment, the first polarization filter 3-1 and the second polarization filter 3-2 can realize angle adjustment within a range of 360 ° with an accuracy of <0.1 ° in their respective planes through their respective corresponding angle adjustment mechanisms, so that the film polarization defect detection apparatus in this application is not only suitable for the film 1 with small alignment angle fluctuation, but also suitable for the polarization defect detection of the film 1 with large alignment angle fluctuation.

Specifically, the angle adjusting mechanism includes a fixing portion 8 whose inner ring is fixed with the polarization filter and which can rotate the polarization filter in the plane where the polarization filter is located, and a driving portion 6 which drives the fixing portion 8 to rotate, the fixing portion 8 can rotate within a range of 360 ° under the action of the driving portion 6, so that the polarization filters can be respectively adjusted in angle within a range of 360 ° with an accuracy of <0.1 ° in each plane, for the angle adjusting mechanism corresponding to the first polarization filter 3-1, the inner ring of the fixing portion 8 fixes the first polarization filter 3-1, for the angle adjusting mechanism corresponding to the second polarization filter 3-2, the inner ring of the fixing portion 8 fixes the second polarization filter 3-2, and the driving portion 6 is driven by a stepping motor or a servo motor, such as a two-phase hybrid stepping motor step, a five-phase hybrid stepping motor, a three-phase hybrid stepping motor, and the like, because the servo motor can easily achieve a control accuracy of 0.1 ° or less, and is superior to vibration, stability, and response performance to a common stepping motor, and therefore the driving portion 6 is preferably driven by a servo motor. In order to realize that the driving portion 6 drives the fixing portion 8 to rotate, specifically, the fixing portion 8 and the driving portion 6 may both adopt a gear structure, and both form a gear transmission structure, in this embodiment, the fixing portion 8 and the driving portion 6 both adopt a pulley structure and are connected through the synchronous belt 7. In the angle adjustment mechanism, the diameter of the driving portion 6 is smaller than the diameter of the fixing portion 8, and the diameter ratio between the driving portion 6 and the fixing portion 8 achieves an effect of enlarging the adjustment precision, and achieves an effect of adjusting the angle within a range of 360 ° with an accuracy of <0.1 ° in a plane, and in order to achieve an optimal effect of enlarging the adjustment precision and considering convenience of installation, the diameter ratio between the driving portion 6 and the fixing portion 8 of the angle adjustment mechanism of the first polarization filter 3-1 is preferably > 1; in the angle adjustment mechanism of the second polarization filter 3-2, the ratio of the diameter of the driving part 6 to the diameter of the fixing part 8 is not more than 1.

In this embodiment, the first polarized light filter 3-1 and the second polarized light filter 3-2 are both circular polarized light filters, and for installation convenience, the diameter of the second polarized light filter 3-2 is only required to be larger than the lens of the camera 4, and is generally not more than 50mm. The diameter of the first polarizing filter 3-1 needs to cover the field of view observed by the camera 4 and is typically larger than 300mm.

In order to match the film 1 having a large fluctuation in alignment angle, it is preferable that the light source 2, the first polarization filter 3-1, the second polarization filter 3-2, and the camera 4 constitute an inspection unit group, and the inspection device includes a plurality of inspection unit groups arranged in the width direction of the film 1, and the first polarization filter 3-1 and the second polarization filter 3-2 of each inspection unit group are provided with the above-described angle adjusting mechanism capable of angularly adjusting the first polarization filter 3-1 and the second polarization filter 3-2 within 360 ° with an accuracy of <0.1 ° in each plane. When the inspection unit groups are arranged in parallel on a straight line along the width direction of the film 1, projections irradiated on the film 1 by two adjacent light sources 2 may have an overlapping portion, generating halo, and affecting the detection effect of the overlapping portion, and therefore, it is preferable that a plurality of the inspection unit groups are arranged in a staggered manner in the width direction of the film 1 to prevent the halo of the overlapping portion from affecting the detection effect. The staggered arrangement is only required to ensure that the horizontal distance of the projections of the two adjacent first polarization filters 3-1 on the film 1 is-20mm to-0mm, and the vertical distance of the projections of the two adjacent first polarization filters 3-1 on the film 1 is greater than 0, and for example, the multiple sets of devices are arranged in a W-shaped and N-shaped manner. The horizontal direction refers to the width direction of the film 1, and the vertical direction refers to the conveying direction of the film 1.

In the film polarization defect detection device in the embodiment, during detection, the first polarization filter 3-1 and the second polarization filter 3-2 are ensured to rotate synchronously through respective angle adjusting mechanisms, the orthogonal nicols method is adopted, the orientation main shafts of the two polarization filters are kept in an orthogonal state, the darkest picture is input into the camera 4, the angle is changed to adapt to different film 1 alignment angles, the optimal side detection effect is achieved, and the angles of the polarization filters in each area are different. The principle is that when the alignment angle of the film 1 is 0 ° and the alignment principal axes of the two polarizing filters are kept in an orthogonal state, the difference between black and white received by the camera 4 is most obvious, and the crystal point halo can be obviously detected. When the orientation main axes of the two polarized filters keep orthogonal state and synchronously rotate, the alignment angle of the film 1 can be compensated, the condition when the alignment angle is 0 degree is simulated, and the optimal detection effect is achieved.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and are not intended to limit the spirit and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made by the technical solution of the present invention by those skilled in the art should fall into the protection scope of the present invention, and the technical contents claimed by the present invention have been fully recorded in the claims.

Claims

1. A film polarization defect detection apparatus, comprising:

a light source (2) that illuminates the film (1) on one side of the film (1);

a first polarizing filter (3-1) disposed between the light source (2) and the film (1);

a second polarizing filter (3-2) disposed opposite to the first polarizing filter (3-1) and on the other side of the film (1);

a camera (4) which is provided on the side of the second polarization filter (3-2) remote from the film (1) and receives transmitted light irradiated from the light source (2) and transmitted through the first polarization filter (3-1), the film (1), and the second polarization filter (3-2);

the first polarized light filter (3-1) and the second polarized light filter (3-2) are respectively provided with an angle adjusting mechanism;

the first polarization filter (3-1) and the second polarization filter (3-2) can realize angle adjustment within a range of 360 degrees with an accuracy of <0.1 degrees in respective planes through respective corresponding angle adjustment mechanisms.

2. A film polarization defect detection device according to claim 1, wherein said light source (2), first polarization filter (3-1), second polarization filter (3-2) and camera (4) constitute an inspection unit group, the detection device comprises a plurality of said inspection unit groups arranged in the width direction of said film (1), and the first polarization filter (3-1) and the second polarization filter (3-2) of each inspection unit group are provided with said angle adjusting mechanism capable of adjusting the angles of the first polarization filter (3-1) and the second polarization filter (3-2) within the respective planes within a range of 360 ° with an accuracy of <0.1 °.

3. A film polarization defect detecting device according to claim 1 or 2, wherein the angle adjusting mechanism comprises a fixing part (8) with the polarization filter fixed at the inner ring and capable of rotating the polarization filter in the plane of the polarization filter, and a driving part (6) for driving the fixing part (8) to rotate.

4. A film polarization defect detecting device according to claim 3, wherein the fixing portion (8) and the driving portion (6) are both of a belt wheel structure and connected by a synchronous belt (7).

5. A film polarization defect detecting device according to claim 3, wherein the fixing portion (8) and the driving portion (6) are both gear structures, and both form a gear transmission structure.

6. A film polarization defect detection device according to claim 3, wherein the driving section (6) is driven by a stepping motor or a servo motor.

7. A film polarization defect detection device according to claim 4 or 5, characterized in that the diameter of the driving portion (6) is smaller than the diameter of the fixing portion (8).

8. The film polarization defect detection device according to claim 7, wherein the angle adjustment mechanism of the first polarization filter (3-1) has a diameter ratio of the driving part (6) to the fixing part (8) of > 1; the ratio of the diameter of the driving part (6) to the fixed part (8) of the angle adjusting mechanism of the second polarization filter (3-2) is not more than 1.

9. A film polarization defect inspection apparatus according to claim 2, wherein a plurality of said inspection unit groups are arranged in a staggered manner in a width direction of the film (1).

10. A film polarization defect detecting device according to claim 1, wherein said first polarization filter (3-1) and said second polarization filter (3-2) are circular polarization filters.