JP6609998B2 - Light irradiation apparatus and light irradiation method - Google Patents

Description

  The present invention relates to a light irradiation apparatus and a light irradiation method for irradiating a work on a work stage with light.

In recent years, a technique called photo-alignment has been adopted in which alignment is performed by irradiating polarized light of a predetermined wavelength with respect to alignment processing of alignment films for liquid crystal display elements such as liquid crystal panels and alignment layers for viewing angle compensation films. Has been.
The light irradiation device used for photo-alignment includes a linear light source having a length corresponding to the width of the light irradiation region, and a polarizing element that polarizes light from the light source, and is orthogonal to the longitudinal direction of the light source. Irradiate polarized light to the workpiece conveyed in the direction.
As such a light irradiation apparatus, there exists a technique of patent document 1, for example. This technique employs a so-called twin stage system in which two stages reciprocate under a lamp. In this way, by moving the two stages to the irradiation region alternately and irradiating the work on the stage with light, the tact time can be reduced compared to the case where only one stage is provided. it can.

JP 2014-174352 A

Photo-alignment processing has been developed not only for large substrates such as liquid crystal panels for television screens, but also for small and medium liquid crystal displays such as for smartphones. However, the installation area (footprint) of the conventional apparatus is excessive for such small and medium substrates.
Then, this invention makes it the subject to provide the light irradiation apparatus and light irradiation method which can improve the processing efficiency per footprint.

In order to solve the above-described problem, an aspect of the light irradiation apparatus according to the present invention is a light irradiation apparatus that irradiates polarized light onto a workpiece that passes through a preset irradiation region, and a conveyance axis that passes through the irradiation region. And a plurality of mounting surfaces on which workpieces are respectively placed in parallel to a plane including the first direction and the second direction, spaced apart from each other in a second direction orthogonal to the extending first direction. The stage and the plurality of stages are fixed in common so that they cannot be individually moved in the first direction, and the plurality of stages are moved from the standby area set outside the irradiation area on the transport axis. A first moving mechanism that moves simultaneously toward the irradiation region, and a rotation that is individually provided on each of the plurality of stages, and that individually rotates the plurality of stages around an axis orthogonal to the placement surface. And a mechanism .
Thereby, a several workpiece | work can be light-irradiated simultaneously. Further, the footprint in the X direction can be reduced as compared with a twin-stage type light irradiation device. Therefore, the processing efficiency per footprint can be improved and productivity can be improved.

In the light irradiation apparatus, the second direction may be a direction in which a linear light source that irradiates the polarized light extends. Thereby, the processing efficiency can be improved without increasing the footprint.
Furthermore, in said light irradiation apparatus, the conveyance for carrying in and carrying out the said workpiece | work from said 2nd direction with respect to said several stage in said waiting area to one side in said 2nd direction of said waiting area An area may be further provided. In this way, since the positions of the standby area and the conveyance area in the first direction are the same position, the light irradiation process starts immediately from the position where the workpiece is loaded, or from the position where the light irradiation process is completed. You can start unloading the workpiece immediately. Moreover, since the work is carried in and out from the second direction, an increase in the footprint in the first direction can be suppressed.

The light irradiation apparatus may further include a second moving mechanism that is provided in common to the plurality of stages and moves the plurality of stages simultaneously in the second direction. Thereby, the contact of the stages resulting from a several stage moving individually can be avoided.
Furthermore, in said light irradiation apparatus, the conveyance for carrying in and carrying out the said workpiece | work from said 2nd direction with respect to said several stage in said waiting area to one side in said 2nd direction of said waiting area The second moving mechanism may further move the plurality of stages simultaneously in the second direction and move the plurality of stages to the transfer region when loading and unloading the workpiece. . Thereby, when delivering a workpiece | work from an external conveying apparatus, a some stage can be closely approached to a conveying apparatus. Therefore, the workpiece replacement process can be performed quickly and stably.

The light irradiation apparatus may further include a second moving mechanism that is individually provided on each of the plurality of stages and moves the plurality of stages individually in the second direction. Thereby, the distance between the stages of the plurality of stages in the second direction can be adjusted.
Further, in the light irradiation apparatus, the standby area may be set at a position close to the irradiation area on the transport axis. Thereby, the footprint in the first direction can be further reduced. Moreover, the conveyance time of the workpiece | work outside an irradiation area | region can be shortened, and a tact time can be shortened.

The light irradiation apparatus may further include a polarization measuring unit that is movable on the transport axis and measures the polarized light in the irradiation region, and the standby region includes the irradiation region and the polarization measuring unit. It may be set between the retracted area when the polarized light is not measured.
As described above, by providing the polarization measuring unit, it is possible to confirm whether or not the polarization axis of the polarized light is a desired polarization axis. In addition, when the polarized light is not measured, the polarization measuring unit can be retracted to a position that is not affected by the light irradiation process.

Furthermore, the light irradiation apparatus may further include a plurality of alignment mark detection units that are provided corresponding to the plurality of stages and that respectively detect alignment marks provided on the workpiece on the plurality of stages. Good. Thereby, an alignment process can be performed on each workpiece placed on each stage. Since each stage can be individually rotated by a rotation mechanism, each workpiece can be corrected to a desired direction by an alignment process.
In the light irradiation apparatus, the alignment mark detection unit is arranged side by side in at least one of the first direction and the second direction, and detects at least a pair of alignment marks provided on the workpiece. At least a pair of detectors may be provided. Thereby, the direction of the workpiece placed on each stage can be appropriately corrected based on the first direction and the second direction.
Further, in the above light irradiation apparatus, the forward movement from the standby area to the irradiation area and the backward movement from the irradiation area to the standby area for a plurality of works placed on the plurality of stages. You may irradiate the said polarized light by both. Thereby, a light irradiation process can be performed without wasting energy.

  The light irradiation apparatus of the present invention includes a plurality of stages that are arranged side by side in the second direction and can reciprocate simultaneously in the first direction, and polarized light is simultaneously applied to the workpieces respectively placed on the plurality of stages. Irradiate. Therefore, the processing efficiency per footprint can be improved. Further, since the plurality of stages can be individually rotated, the optical alignment process can be appropriately performed.

It is a schematic block diagram which shows the polarized light irradiation apparatus of this embodiment. It is a side view which shows schematic structure of a conveyance part. It is a figure explaining the movement area of a stage. It is a flowchart which shows operation | movement of a polarized light irradiation apparatus. It is a figure explaining operation | movement of 1st embodiment. It is a figure explaining operation | movement of 1st embodiment. It is a figure explaining operation | movement of 1st embodiment. It is a figure explaining operation | movement of 1st embodiment. It is a figure explaining operation | movement of 1st embodiment. It is a figure explaining operation | movement of 1st embodiment. It is a figure explaining operation | movement of 1st embodiment. It is a figure explaining operation | movement of 1st embodiment. It is a size comparison with a twin stage type polarized light irradiation device. It is a comparison result of processing tact of various types of polarized light irradiation apparatus. It is a figure which shows another example of operation | movement of 1st embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a schematic configuration diagram showing a polarized light irradiation apparatus 100 of the present embodiment.
The polarized light irradiation device 100 includes light irradiation units 10 </ b> A and 10 </ b> B and a transport unit 20 that transports the workpiece W. Here, the workpiece W is a rectangular substrate on which a photo-alignment film is formed, for example, shaped to the size of a liquid crystal panel. The work W in the present embodiment is a substrate used for a small and medium-sized liquid crystal display such as a smartphone, an industrial monitor, a medical monitor, or an in-vehicle monitor.
The polarized light irradiation apparatus 100 linearly moves the workpiece W by the transport unit 20 while irradiating polarized light (polarized light) having a predetermined wavelength from the light irradiation units 10A and 10B, and the polarized light is applied to the photo-alignment film of the workpiece W. Light alignment is performed by irradiating light.

Each of the light irradiation units 10A and 10B includes a lamp 11 that is a linear light source and a mirror 12 that reflects the light from the lamp 11. The light irradiation units 10A and 10B each include a polarizer unit 13 disposed on the light emission side. Further, each of the light emitting units 10A and 10B includes a lamp house 14 that houses the lamp 11, the mirror 12, and the polarizer unit 13, respectively.
The light irradiation unit 10A and the light irradiation unit 10B are configured so that the longitudinal direction of the lamp 11 matches the direction (second direction: Y direction) orthogonal to the conveyance direction (first direction: X direction) of the workpiece W. It is arranged in parallel along the conveyance direction (X direction) of W. In addition, in FIG. 1, although the lamp (light irradiation part) is 2 lights, 1 light may be sufficient and 3 or more lights may be sufficient.

Hereinafter, specific configurations of the light irradiation units 10A and 10B will be described.
The lamp 11 is a long so-called long arc discharge lamp, and the light emitting portion thereof has a length corresponding to the width in the direction orthogonal to the conveying direction of the workpiece W. This lamp 11 is, for example, a discharge lamp such as a high-pressure mercury lamp, a metal halide lamp in which other metal and halogen are added to mercury, or a metal halide lamp in which a metal other than mercury and halogen is enclosed. Accordingly, ultraviolet light having a wavelength of 200 nm to 400 nm is emitted.
As materials for the photo-alignment film, those that are aligned by light having a wavelength of 254 nm, those that are aligned by light having a wavelength of 313 nm, and materials that are aligned by light having a wavelength of 365 nm are known. It selects suitably according to the wavelength to be performed.
As the light source, a linear light source in which LEDs or LDs that emit ultraviolet light are arranged in a straight line can be used. In that case, the direction in which the LEDs and LDs are arranged corresponds to the longitudinal direction of the lamp.

The mirror 12 reflects the radiated light from the lamp 11 in a predetermined direction, and is a bowl-shaped condensing mirror whose section is elliptical or parabolic. The mirror 12 is arranged such that its longitudinal direction coincides with the longitudinal direction of the lamp 11.
The lamp house 14 has, on the bottom surface thereof, a light exit port through which radiated light from the lamp 11 and reflected light from the mirror 12 pass. The polarizer unit 13 is attached to the light exit of the lamp house 14 and polarizes light passing through the light exit.
The polarizer unit 13 has a configuration in which a plurality of polarizers are arranged side by side along the longitudinal direction of the lamp 11. The plurality of polarizers are supported by, for example, a frame.
The polarizer is, for example, a wire grid type polarizing element, and the number of polarizers is appropriately selected according to the size of the region where the polarized light is irradiated. Each polarizer is arranged such that the transmission axis faces the same direction.

  The transport unit 20 includes a first stage 21A and a second stage 21B on which the workpiece W is placed. These two stages 21A and 21B are flat stages that can hold the workpiece W by vacuum suction or the like, and have a mounting surface on which the workpiece W is mounted in parallel with the XY plane. In the present embodiment, the stages 21A and 21B and the workpiece W are rectangular, but the present invention is not limited to this and may be any shape. In addition, the work W is sucked and held by a flat stage, but the present invention is not limited to this, and the work W may be sucked and held by a plurality of pins.

In addition, the transport unit 20 includes an X-direction drive mechanism 22 for moving the stages 21A and 21B in the X direction, and a Y-direction drive mechanism 23 for moving the stages 21A and 21B in the Y direction.
The X-direction drive mechanism 22 includes two guides 22A extending along the X direction and an electromagnet 22B that configures the X-direction drive mechanism 22 as an example. In the present embodiment, for example, a linear motor stage is employed as the X-direction drive mechanism 22. The linear motor stage applies a magnetic force to a moving body on a planar platen provided with a ferromagnetic convex pole in a grid pattern or a line shape, and between the moving body and the convex pole of the platen. It is a mechanism that moves the moving body by changing the magnetic force. As the X-direction drive mechanism 22, for example, a mechanism using a ball screw can be adopted.

The Y-direction drive mechanism 23 includes, for example, a guide 23A that extends in the Y direction and is fixed on the X-direction drive mechanism 22, and a slider portion 23B that can reciprocate in the Y direction along the guide 23A. The stages 21A and 21B are fixed to the upper surface of the slider portion 23B via a later-described θ rotation mechanism (not shown in FIG. 1). The first stage 21A and the second stage 21B are arranged side by side in a state of being spaced apart from each other by a certain distance in the Y direction.
As described above, the stages 21A and 21B are configured to be capable of reciprocating in the X direction simultaneously along the guide 22A serving as the transport shaft and simultaneously reciprocating in the Y direction along the guide 23A. Note that the configurations of the X-direction drive mechanism 23 and the Y-direction drive mechanism 24 are not limited to the configurations shown in FIG. 1, and any configurations are possible as long as the stages 21A and 21B can move in the X direction and the Y direction, respectively. The configuration can be adopted.

  FIG. 2 is a side view illustrating a schematic configuration of the transport unit 20. FIG. 2 is a view of the transport unit 20 as viewed from the X direction. Thus, the stages 21A and 21B are fixed to the common X-direction drive mechanism 22. The stages 21A and 21B are fixed to a common Y-direction drive mechanism 23 via θ rotation mechanisms 24A and 24B, respectively. The θ rotation mechanism 24A can rotate the first stage 21A in the θ direction (around the Z axis), and the θ rotation mechanism 24B can rotate the second stage 21B in the θ direction (around the Z axis). With the above configuration, the stages 21A and 21B can move in the X direction and the Y direction at the same time while being arranged in parallel in the Y direction, and can individually rotate in the θ direction. The X-direction drive mechanism 22, the Y-direction drive mechanism 23, and the θ rotation mechanisms 24A and 24B are controlled by the control unit 25, respectively.

  The moving paths of the stages 21A and 21B are designed to pass directly under the light irradiation units 10A and 10B. The conveyance part 20 is comprised so that the workpiece | work W may be conveyed to the irradiation area | region of the polarized light by the light irradiation parts 10A and 10B, and the irradiation area | region may be allowed to pass through. Furthermore, after the workpiece W has completely passed through the irradiation area, the transport unit 20 is configured to return the workpiece W and pass the irradiation area again. In both the forward movement and the backward movement, the photo-alignment film of the workpiece W is subjected to photo-alignment processing.

  Further, as shown in FIG. 1, the polarized light irradiation apparatus 100 is a polarization measuring device 30 for measuring the polarization axis of the polarized light irradiated from the light irradiation units 10A and 10B (the axis of the polarized light on the light irradiation surface). Is provided. The polarization measuring device 30 can be transported in the X direction and the Y direction by a configuration substantially the same as that of the transport unit 20. When measuring the polarized light, the polarization measuring device 30 is conveyed from the predetermined retracted position along the guide 22A to the irradiation region of the polarized light by the light irradiation units 10A and 10B. Then, the polarization measuring device 30 measures the polarization axis immediately below each polarizer while moving in the Y direction (the arrangement direction of the polarizers of the polarizer units 13A and 13B) while being in the irradiation region.

FIG. 3 is a diagram for explaining the moving section of the stages 21A and 21B.
The polarized light irradiation apparatus 100 includes a housing 51 that accommodates the units illustrated in FIG. The casing 51 is formed with a conveyance port 52 for carrying the workpiece W in and out of the polarized light irradiation apparatus 100 on the side wall in the Y direction. Loading and unloading of the workpiece W is performed by a transfer robot (transfer apparatus) 200 disposed outside the polarized light irradiation apparatus 100. The transfer robot 200 includes a transfer arm 201 that can move in the Y direction. The transfer arm 201 mounts the work W before the light irradiation process on the stages 21A and 21B, and collects the work W after the light irradiation process from the stages 21A and 21B. Further, the transfer arm 201 has a configuration capable of delivering the workpiece W between the stages 21A and 21B.

  The stages 21A and 21B move from the workpiece standby position (standby area) 53 set on one side of the polarized light irradiation area (effective irradiation area) 15 by the light irradiation units 10A and 10B in the X direction. It is possible to reciprocate in the section up to the folding position 54 set on the other side. Here, the movement of the stages 21 </ b> A and 21 </ b> B from the workpiece standby position 53 toward the return position 54 is referred to as an outward movement, and the movement from the return position 54 to the workpiece standby position 53 is referred to as a return path movement. The workpiece standby position 53 is a position where the workpiece W is exchanged and aligned, and the turn-back position 54 is a switching position from the forward movement of the stages 21A and 21B to the backward movement.

The workpiece standby position 53 is such that the polarized light from the light irradiation unit 10A is not irradiated to the workpiece W on the stages 21A and 21B, regardless of the postures of the stages 21A and 21B that are rotationally moved in the θ direction. It is set at a position close to the light irradiation unit 10A. Similarly, the folding position 54 does not irradiate the work W on the stages 21A and 21B with the polarized light from the light irradiation unit 10B, regardless of the posture of the stages 21A and 21B due to the rotational movement in the θ direction. The position is set close to the light irradiation unit 10B. Furthermore, the workpiece standby position 53 is set between the retracted position (retracted area) 55 of the polarization measuring device 30 shown in FIG.
Further, the X direction position of the transport port 52 is set to the same position as the X direction position of the workpiece standby position 53. In other words, on one side of the workpiece standby position 53 in the Y direction, a conveyance area for carrying the workpiece W in and out of the plurality of stages 21A and 21B at the workpiece standby position 53 is provided.

Above the first stage 21 </ b> A at the workpiece standby position 53, a pair of alignment cameras 41 for performing alignment work of the workpiece W on the first stage 21 </ b> A is provided. In addition, a pair of alignment cameras 42 are provided above the second stage 21B at the workpiece standby position 53 for performing an alignment operation of the workpiece W on the second stage 21B.
The workpiece W is provided with a pair of alignment marks for defining the alignment completion position of the workpiece W, and the pair of alignment cameras detect the pair of alignment marks one by one. In the present embodiment, the pair of alignment cameras 41 and 42 are arranged side by side on an axis parallel to the X direction. Then, based on the alignment mark detection position, an alignment process is performed in which the stages 21A and 21B are rotationally moved in the θ direction so that the pair of alignment marks are aligned on an axis parallel to the X direction. That is, in the present embodiment, the position (θ angle) of the workpiece W when the pair of alignment marks are arranged on an axis parallel to the X direction is set as the alignment completion position.

Each of the stages 21A and 21B can be rotated in the θ direction within a circle 43 indicated by a one-dot chain line, and the workpiece W placed on each of the stages 21A and 21B can be rotated in the θ direction together with the stages 21A and 21B. Is possible. It should be noted that the stages 21A and 21B are arranged apart from each other in the Y direction so that the stages 21A and 21B or the workpiece W do not interfere with each other, regardless of the posture by the rotational movement in the θ direction. Here, the separation distance in the Y direction between the stages 21A and 21B is preferably set in consideration of the placement error of the workpiece W with respect to the stages 21A and 21B.
In addition, the alignment camera should just be provided with at least 1 pair (2 pieces) with respect to the one workpiece | work W, and the number of installation is not limited above. In addition, the direction in which the pair of alignment cameras are arranged can be appropriately set according to the direction of the pair of alignment marks at the alignment completion position. That is, when the alignment process is performed so that the pair of alignment marks are arranged on an axis parallel to the Y direction, the pair of alignment cameras are arranged side by side on an axis parallel to the Y direction.

The basic operation of the stages 21A and 21B is as follows.
The stages 21 </ b> A and 21 </ b> B are subjected to workpiece W replacement processing and alignment processing at the workpiece standby position 53. After the alignment is completed, the stages 21A and 21B are rotated and moved to preset light irradiation angles by the θ rotation mechanisms 24A and 24B, respectively. Thereby, the direction of the workpiece W is set to a predetermined direction with respect to the polarization axis of the polarized light.
Thereafter, the stages 21 </ b> A and 21 </ b> B simultaneously start the outward movement toward the irradiation region 15. Then, when passing through the irradiation area 15 and reaching the turn-back position 54, the backward movement is started at the same time, and the work is returned to the work standby position 53. At the workpiece standby position 53, the workpiece W replacement process and the alignment process are performed again. After the alignment is completed, the stages 21A and 21B simultaneously start the outward movement toward the irradiation region 15 again. This operation is repeated.
The control unit 25 illustrated in FIG. 2 controls each unit of the transport unit 20 so as to realize the above-described stage operation.
In the above description, the X-direction drive mechanism 22 corresponds to the first movement mechanism, the Y-direction drive mechanism 23 corresponds to the second movement mechanism, and the θ rotation mechanisms 24A and 24B correspond to the rotation mechanism. The alignment cameras 41 and 42 correspond to the alignment mark detection unit.

Hereinafter, the operation of this embodiment will be described in detail.
FIG. 4 is a flowchart showing the operation of the polarized light irradiation apparatus 100.
First, in step S1, the control unit 25 drives and controls the Y-direction drive mechanism 23, and moves the stages 21A and 21B from the state at the workpiece standby position shown in FIG. Then, the work W is carried in by the transfer robot 200. At this time, as shown in FIG. 5, the transfer robot 200 moves the transfer arm 201 holding the two workpieces W in the Y direction and inserts it into the housing 51 from the transfer port 52. Then, for example, the workpiece W is transferred from the transfer arm 201 to the stages 21A and 21B at the position shown in FIG. As a result, the workpiece W is attracted and held on the stages 21A and 21B, respectively.

For example, when the transfer arm 201 is sufficiently long and the transfer arm 201 can enter the workpiece standby position of the stages 21A and 21B, the stages 21A and 21B are set to Y when the workpiece W is transferred. It does not have to move in the direction. In this case, however, a transfer arm 201 having a length of several meters is required. Further, in this case, since the end of the transfer arm 201 has a cantilever shape that holds the workpiece W, the holding of the workpiece W becomes unstable and the transfer accuracy of the workpiece W may be lowered.
Therefore, as shown in FIG. 5, it is preferable to move the stages 21 </ b> A and 21 </ b> B in the Y direction so as to approach the transfer arm 201 and transfer the workpiece W. With such a configuration, the workpiece W can be delivered stably, and the time required for the workpiece W replacement operation can be shortened.

In the present embodiment, the transfer robot 200 is configured to transfer two workpieces W at the same time and place them on the stages 21A and 21B at the same time. However, the present invention is not limited to this, and the transfer robot 200 may be configured to transfer the workpieces W one by one and place them one by one on the work stage. However, a configuration in which a plurality of workpieces W can be transported and placed at the same time is preferable because the time required for the workpiece W replacement work is shortened.
When the delivery of the workpiece W from the transfer arm 201 to the stages 21A and 21B is completed, in step S2 of FIG. 4, the transfer robot 200 moves the transfer arm 201 in the Y direction as shown in FIG. Retreat from the mouth 52 to the outside of the casing 51. At the same time, the control unit 25 controls the drive of the Y-direction drive mechanism 23 and returns the stages 21A and 21B to the workpiece standby position as shown in FIG.

  Next, in step S3, alignment marks provided on the workpiece W are detected by the alignment cameras 41 and 42, respectively. As illustrated in FIG. 8, depending on the accuracy of transfer of the workpiece W by the transfer robot 200, a different shift may occur for each workpiece W when the workpiece W is placed on the stage. The alignment cameras 41 and 42 shown in FIG. 7 grasp the situation of these deviations. The alignment camera 41 detects the alignment mark AM of the workpiece W placed on the first stage 21A in the region 44 of FIG. Further, the alignment camera 42 detects the alignment mark AM of the workpiece W placed on the second stage 21B in the region 45 of FIG.

  When the alignment mark AM is detected by the alignment cameras 41 and 42, the control unit 25 performs an alignment process in step S4 of FIG. Specifically, the control unit 25 individually drives and controls the X-direction drive mechanism 22, the Y-direction drive mechanism 23, and the θ rotation mechanisms 24A and 24B, and the pair of alignment marks AM of the workpieces W are arranged in the X direction. The stages 21A and 21B are moved in the X, Y, and θ directions so that the alignment marks AM are as close as possible to the center positions of the regions 44 and 45, respectively.

  The X-direction drive mechanism 22 and the Y-direction drive mechanism 23 are common to the two stages 21A and 21B, respectively, and the first stage 21A and the second stage 21B cannot move individually in the X direction and the Y direction. It is a configuration. Therefore, the position of each alignment mark AM does not have to completely coincide with the center position of the regions 44 and 45, respectively. That is, there is no need to adjust the stage interval in the X direction and the Y direction. Furthermore, in the photo-alignment process, it is only necessary to perform at least the alignment process in the θ rotation direction, and the alignment process in the X direction and the Y direction can be omitted.

  When the alignment process is completed, in step S5 in FIG. 4, the control unit 25 controls the driving of the θ rotation mechanisms 24A and 24B, and as shown in FIG. 9, the workpiece W is moved by the preset light irradiation angle from the alignment completion position. Rotate. Here, the light irradiation angle of the workpiece W may be different for each workpiece W. For example, when a TFT (Thin Film Transistor) substrate and a CF (Color Filter) substrate constituting a liquid crystal panel are placed on the first stage 21A and the second stage 21B, respectively, and the light irradiation process is performed, the light irradiation is performed. The angle differs between the TFT substrate and the CF substrate. For example, if the rotation angle of the TFT substrate is −10 °, the rotation angle of the CF substrate is + 10 °, and the positive and negative signs are reversed. As described above, the polarized light irradiation apparatus 100 may perform light irradiation processing on both different types of workpieces W such as a TFT substrate and a CF substrate at the same time.

  When the workpiece W is rotated and moved so as to have the light irradiation angle, the stages 21A and 21B are ready to start the forward movement. Then, in step S6 of FIG. 4, the control unit 25 controls the driving of the X-direction drive mechanism 23, and simultaneously moves the stages 21A and 21B in the X direction to perform the light irradiation process of the workpiece W. First, the control unit 25 moves the stages 21A and 21B forward from the workpiece standby position shown in FIG. 9 toward the return position shown in FIG. At this time, the workpiece W is irradiated with light in the process of passing through the irradiation region 15. When the stages 21A and 21B reach the return position, the control unit 25 moves the stages 21A and 21B in the backward direction from the return position shown in FIG. 10 to the workpiece standby position shown in FIG. Also in this return path movement, the workpiece W is subjected to the light irradiation process in the process of passing through the irradiation region 15.

During the above-described reciprocal exposure, the control unit 25 may control the moving speeds of the stages 21A and 21B to different speeds in the irradiation area 15 and outside the irradiation area 15. For example, the stages 21 </ b> A and 21 </ b> B are moved outside the irradiation area 15 at a relatively high first movement speed (for example, maximum movement speed), and inside the irradiation area 15 is a second speed that is lower than the first movement speed. You may control to move at a moving speed. Here, the second moving speed is set to a speed at which a predetermined exposure amount set in advance can be obtained. In this way, the tact time can be shortened by controlling the stage moving speed so as to move outside the irradiation region 15 at a higher speed than in the irradiation region 15.
When the light irradiation process of the workpiece W is completed and the stages 21A and 21B return to the workpiece standby position, in step S7 in FIG. 4, the control unit 25 drives and controls the θ rotation mechanisms 24A and 24B, and the stages 21A and 21B are moved to the workpiece. Rotate to W alignment complete position. That is, as shown in FIG. 12, the control unit 25 reversely rotates the stages 21A and 21B by the amount that the stages 21A and 21B are rotated in step S5.

  Next, in step S <b> 8 in FIG. 4, the work W after the light irradiation process is carried out by the transfer robot 200. Here, an operation opposite to the loading of the workpiece W in step S1 may be performed. That is, the control unit 25 first drives and controls the Y-direction drive mechanism 23, and moves the stages 21 </ b> A and 21 </ b> B on which the work W after the light irradiation process is placed toward the transport port 52. The transfer robot 200 moves the transfer arm 201 that does not hold the workpiece W in the Y direction and inserts the transfer arm 201 into the housing 51 from the transfer port 52. Then, for example, the workpiece W is transferred from the stages 21A and 21B to the transfer arm 201 at the position shown in FIG. When the delivery of the workpiece W is completed, the transfer robot 200 retracts the transfer arm 201 from the transfer port 52 to the outside of the casing 51. Thereby, the work W after the light irradiation process is carried out of the housing 51.

Next, in step S9, the control unit 25 determines whether or not to end the light irradiation process. When it is determined that the light irradiation process is to be continued, the control unit 25 returns to step S1 and when it is determined to end the light irradiation process. Ends the operation as it is.
As described above, the polarized light irradiation apparatus 100 according to the present embodiment is provided in parallel with two work stages (first stage 21A and second stage 21B) that are arranged side by side in the Y direction and can reciprocate simultaneously in the X direction. ) And simultaneously irradiates polarized light onto the substrates (work W) respectively mounted on the two work stages. Here, each of the two work stages is configured to be capable of rotating θ individually.

In recent years, the photo-alignment film has been enlarged along with the enlargement of the liquid crystal panel for television screens in which it is used. Therefore, the width of the irradiation region of the polarized light is widened to 1500 mm or more. On the other hand, photo-alignment processing has been developed not only for television screens but also for small and medium-sized liquid crystal displays such as smartphones, and production of liquid crystal displays of various types and dimensions is expected.
In that case, the size of the substrate itself is often smaller than before, and the installation occupation area, so-called footprint, is excessive in the conventional apparatus. Further, when the so-called twin stage system is adopted in which the two stages reciprocate directly under the lamp, the footprint in the X direction in which the stage is conveyed is large. However, it is not just a matter of downsizing a conventional device, and it is necessary to efficiently process substrates of various sizes for small and medium-sized liquid crystal displays.

The polarized light irradiation apparatus 100 in the present embodiment can have a smaller footprint in the X direction than the twin-stage type polarized light irradiation apparatus with the above-described configuration. In addition, tact time can be reduced and productivity can be improved as compared with a twin-stage polarized light irradiation apparatus. As described above, the polarized light irradiation apparatus 100 can realize the minimization of the footprint and the efficient production of the small and medium-sized display. Hereinafter, this point will be described.
FIG. 13 is a diagram comparing the footprints of the twin-stage polarized light irradiation device and the polarized light irradiation device 100 according to the present embodiment. As illustrated in FIG. 13A, the twin-stage polarized light irradiation apparatus 1000 includes a first work standby position 1053, a first return position 1054, and a retraction position 1055 for the polarization measuring device 30 in the housing 1051. A second workpiece standby position 1056 and a second return position 1057 are provided.

  The polarized light irradiation apparatus 1000 includes a first stage 1021A that can reciprocate between a first workpiece standby position 1053 and a first return position 1054, a second workpiece standby position 1056, and a second return position. 2nd stage 1021B which can be reciprocated between 1057. Then, the polarized light irradiation apparatus 1000 alternately moves the first stage 1021A and the second stage 1021B directly below the light irradiation units 10A and 10B to irradiate the work on the stage with light. Further, the housing 1051 is formed with a conveyance port 1052A for carrying a workpiece in and out of the stage 1021A and a conveyance port 1052B for carrying a workpiece in and out of the stage 1021B.

  On the other hand, as shown in FIG. 13B, the polarized light irradiation apparatus 100 according to the present embodiment has a workpiece standby position 53, a folding position 54, and a retracted position 55 of the polarization measuring device 30 in the housing 51. Only provided. That is, as compared with the polarized light irradiation apparatus 1000 shown in FIG. 13A, areas corresponding to the second workpiece standby position 1056 and the second return position 1056 are not necessary. In addition, the transfer port 1052B for carrying in and out the work with respect to the second stage 1021B is also unnecessary. As described above, the polarized light irradiation apparatus 100 shown in FIG. 13B significantly reduces the footprint in the X direction as compared with the twin stage type polarized light irradiation apparatus 1000 shown in FIG. Can do.

  Further, the discharge lamp used as the lamp 11 of the light irradiation units 10A and 10B has a reduced illuminance at both ends in the longitudinal direction (Y direction) due to its configuration. Therefore, in order to secure an effective irradiation region with uniform illuminance in the Y direction, the length of the light irradiation units 10A and 10B in the Y direction is necessary. That is, the length of the light irradiation units 10A and 10B cannot be shortened even if the size of the workpiece to be subjected to the light irradiation process is small. That is, there is no difference in the Y-direction footprint between the polarized light irradiation apparatus 1000 shown in FIG. 13A and the polarized light irradiation apparatus 100 shown in FIG.

  Since the polarized light irradiation apparatus 100 in the present embodiment has a plurality of stages arranged side by side in the extending direction (Y direction) of the lamp 11 that is a linear light source, compared to a twin stage type polarized light irradiation apparatus, The processing efficiency per footprint can be improved. This is particularly effective when the light irradiation process is performed on the workpiece W having a size equal to or less than half of the length of the lamp in the longitudinal direction, such as when the workpiece W is a substrate for a small and medium display. Moreover, since the polarized light irradiation apparatus 100 can reduce the footprint in the X direction, for example, it can be easily carried into a factory or the like.

FIG. 14 is a comparison result of processing tact (tact time) in polarized light irradiation apparatuses of different methods. In FIG. 14, a straight line Wθ is a polarized light irradiation apparatus 100 in the present embodiment, a straight line S is a single-stage polarized light irradiation apparatus in which one stage reciprocates directly under a lamp, and a polygonal line T is two stages. The tact time of a twin-stage polarized light irradiation device that reciprocates directly under the lamp is shown. The horizontal axis in FIG. 14 represents the exposure amount per workpiece in the irradiation region, and the larger the exposure amount, the longer the irradiation time, that is, the slower the stage speed when passing through the irradiation region. Further, the vertical axis in FIG. 14 represents the tact time (total processing time).
As is clear from FIG. 14, the polarized light irradiation apparatus 100 (Wθ) in this embodiment has two stages arranged in parallel in the Y direction, so that it is different from the single-stage polarized light irradiation apparatus (S). In comparison, the tact time can be simply halved. Further, it can be seen that the polarized light irradiation apparatus 100 (Wθ) in this embodiment can shorten the tact time as compared with the twin-stage polarized light irradiation apparatus (T).

  In the twin stage type polarized light irradiation apparatus (T), when the exposure amount is relatively small (irradiation time is relatively short), a tact time equivalent to that of the polarized light irradiation apparatus 100 (Wθ) can be realized. However, with the inflection point P as a boundary, as the exposure amount increases (the irradiation time becomes longer), the processing tact of the twin stage type polarized light irradiation apparatus (T) is the tact of the polarized light irradiation apparatus 100 (Wθ). It becomes longer than time. This inflection point P is a point at which the irradiation time and the workpiece transfer time become equal. Note that the transfer time is the time during which the workpiece is transferred outside the irradiation area, the transfer time of the work by the transfer robot (mounting time on the stage), the alignment processing time, and the time from the workpiece standby position to the irradiation area. , And the time until it returns from the irradiation area to the workpiece standby position.

As described above, in the twin stage type polarized light irradiation apparatus (T), the larger the exposure amount (the longer the irradiation time), the longer the irradiation waiting time for the next workpiece, and the longer the tact time. Therefore, particularly when the exposure amount per workpiece in the irradiation area is large, the polarized light irradiation apparatus 100 in the present embodiment shortens the overall tact time compared to the twin stage type polarized light irradiation apparatus (T). be able to.
In the polarized light irradiation apparatus 100 of the present embodiment, the first stage 21A and the second stage 21B can be independently controlled for θ rotation. If the configuration is such that a plurality of workpieces W are placed on one workpiece stage having a large area, the plurality of workpieces W rotate around the center position of the workpiece stage by θ rotation. The position will shift. As in this embodiment, a plurality of workpieces W are independently placed on the workpiece stage, and each of them can be independently rotated by θ, so that the workpiece W can be at a desired angle without shifting the XY position. Can be set. Therefore, the direction of the workpiece W can be set to an appropriate direction with respect to the polarization axis of the polarized light, and the optical alignment process can be performed appropriately.

Further, the first stage 21A and the second stage 21B are configured to move simultaneously in the Y direction by a common Y-direction drive mechanism 23. If the two work stages are configured to be independently movable in the Y direction, the stages may come into contact with each other due to, for example, movement in the Y direction during the alignment process. Further, if a Y-direction drive mechanism is provided for each of the plurality of work stages, more space is required. By providing a plurality of work stages on a common base (Y-direction drive mechanism 23) as in this embodiment, contact between the stages as described above can be avoided.
Further, the separation distance in the Y direction between the first stage 21A and the second stage 21B is set to a distance at which the stages do not come into contact with each other regardless of the posture due to the rotational movement in the θ direction. Therefore, it is possible to prevent the stages from coming into contact with each other by the θ rotation during the alignment process.

Further, the workpiece W is carried in and out from the Y direction with respect to the stages 21A and 21B located at the workpiece standby position 53. Thereby, it is possible to start the light irradiation process immediately from the position where the work W is loaded, or to start unloading the work W immediately from the position where the light irradiation process is completed.
Further, when loading and unloading the workpiece W, the stages 21A and 21B are simultaneously moved in the Y direction, and the stages 21A and 21B are moved closer to the transfer arm 201 of the transfer robot 200. Therefore, the work replacement processing time can be shortened.
Furthermore, since the workpiece standby position 53 is set at a position close to the irradiation region 15, the time from when the workpiece W is loaded to when the workpiece W enters the irradiation region 15 after the start of the light irradiation process is minimized. Limit. Therefore, the overall tact time can be shortened.

Further, the workpiece standby position 53 is set between the retracted position 55 of the polarization measuring device 30 and the irradiation area 15. As described above, the light irradiation process can be performed by retracting the polarization measuring unit to a position where the light irradiation process is not affected. Further, since the workpiece W is carried in and out of the stages 21A and 21B at the workpiece standby position 53 from the Y direction, the polarization measuring device 30 and the irradiation region 15 exist on both sides in the X direction of the workpiece standby position 53 as described above. Even if it is doing, the exchange process of the workpiece | work W can be performed appropriately.
In addition, alignment cameras 41 and 42 are provided on the stages 21A and 21B, respectively. Therefore, the alignment process of each workpiece W on the stages 21A and 21B can be appropriately performed. Furthermore, the alignment cameras 41 and 42 are a pair of alignment cameras arranged in at least one of the X direction and the Y direction. Therefore, the direction of the workpiece W placed on each of the stages 21A and 21B can be appropriately corrected based on the X direction and the Y direction.

(Modification)
In the above embodiment, the case where the first Y-direction drive mechanism 23 is provided in the first stage 21A and the second stage 21B has been described. However, the Y-direction is provided in each of the first stage 21A and the second stage 21B. A drive mechanism may be provided. In this case, the first stage 21A and the second stage 21B can be individually moved in the Y direction. Therefore, for example, after the alignment process shown in FIG. 9 is completed, the light irradiation process may be performed by bringing the stages 21A and 21B closer (or in contact) as shown in FIG. Thereby, the length of the discharge lamp 11 in the Y direction can be shortened, and the footprint of the apparatus in the Y direction can be reduced.

Moreover, in the said embodiment, although the case where two work stages were arrange | positioned in the Y direction was demonstrated, you may arrange | position three or more work stages. The number of work stages is set according to the length of the lamp in the Y direction and the transfer capability of the work W by the transfer robot 200.
Further, in the above embodiment, the case where the workpiece W is irradiated with the polarized light in both the forward movement and the backward movement has been described. However, the polarized light may be irradiated with only one of the workpieces. However, in this case, it is necessary to move the stage on which the workpiece W is placed on the way and pass through the irradiation region 15, and then unload the workpiece W at that position. And 2 are required. In this case, after the work W is unloaded, the stage returns to the load position (work standby position) in a state where the work W is not placed, which is inefficient. Therefore, it is preferable to irradiate the work W with polarized light in both the forward movement and the backward movement.

  DESCRIPTION OF SYMBOLS 10A, 10B ... Light irradiation part, 11 ... Discharge lamp, 12 ... Mirror, 13 ... Polarizer unit, 14 ... Lamp house, 15 ... Irradiation area, 20 ... Conveyance part, 21A ... First stage, 21B ... Second Stage, 22 ... X direction drive mechanism, 22A ... Guide, 22B ... Electromagnet, 23 ... Y direction drive mechanism, 24A, 24B ... θ moving mechanism, 25 ... Control unit, 30 ... Polarimeter, 41,42 ... Alignment camera, DESCRIPTION OF SYMBOLS 51 ... Housing | casing, 52 ... Conveying port, 53 ... Work waiting position, 54 ... Folding position, 55 ... Retraction position, 100 ... Polarized light irradiation apparatus

Claims (12)

A light irradiation device for irradiating polarized light to a workpiece passing through a preset irradiation region,
Separated in a second direction orthogonal to the first direction in which the transport axis passing through the irradiation region extends, the workpiece is placed in parallel with the plane including the first direction and the second direction. A plurality of stages having mounting surfaces;
The plurality of stages are fixed in common so that they cannot be individually moved in the first direction, and the plurality of stages are directed from the standby region set outside the irradiation region on the transport axis to the irradiation region. Te, a first moving mechanism causes simultaneous movement,
A light irradiation apparatus comprising: a rotation mechanism that is individually provided on each of the plurality of stages, and that individually rotates the plurality of stages around an axis orthogonal to the placement surface.   The light irradiation apparatus according to claim 1, wherein the second direction is a direction in which a linear light source that irradiates the polarized light extends.   One side of the standby area in the second direction is further provided with a transfer area for loading and unloading the workpiece from the second direction with respect to the plurality of stages in the standby area. The light irradiation apparatus according to claim 1 or 2.   4. The apparatus according to claim 1, further comprising a second moving mechanism that is provided in common to the plurality of stages and moves the plurality of stages simultaneously in the second direction. 5. Light irradiation device. On one side in the second direction of the standby area, further comprising a transfer area for loading and unloading the workpiece from the second direction with respect to the plurality of stages in the standby area,
The second moving mechanism is
5. The method according to claim 4, wherein when the workpiece is loaded and unloaded, the plurality of stages are simultaneously moved in the second direction, and the plurality of stages are moved to the transfer region. Light irradiation device.   4. The apparatus according to claim 1, further comprising a second moving mechanism that is individually provided on each of the plurality of stages and moves the plurality of stages individually in the second direction. The light irradiation apparatus of description.   The light irradiation apparatus according to claim 1, wherein the standby region is set at a position close to the irradiation region on the transport axis. A polarization measuring unit that is movable on the transport axis and that measures the polarized light in the irradiation region;
The said waiting | standby area | region is set between the said irradiation area | region and the evacuation area | region at the time of the non-measurement of the said polarized light of the said polarization measuring part, The any one of Claims 1-7 characterized by the above-mentioned. Light irradiation device.   9. The apparatus according to claim 1, further comprising a plurality of alignment mark detectors respectively provided corresponding to the plurality of stages, each of which detects an alignment mark provided on the workpiece on the plurality of stages. The light irradiation apparatus of any one of Claims. The alignment mark detector
The apparatus according to claim 9, further comprising at least a pair of detectors arranged side by side in at least one of the first direction and the second direction and detecting at least a pair of alignment marks provided on the workpiece. The light irradiation apparatus of description. Irradiating the plurality of workpieces placed on the plurality of stages with the polarized light both in the forward movement from the standby area to the irradiation area and in the backward movement from the irradiation area to the standby area. The light irradiation apparatus of any one of Claims 1-10 characterized by these. A light irradiation method for irradiating a workpiece passing through a preset irradiation region with polarized light,
Separated in a second direction orthogonal to the first direction in which the transport axis passing through the irradiation region extends, the workpiece is placed in parallel with the plane including the first direction and the second direction. Rotating a plurality of stages each having a mounting surface individually around an axis perpendicular to the mounting surface;
The plurality of stages are simultaneously moved from the standby area set outside the irradiation area on the transport axis toward the irradiation area in a state where the plurality of stages are fixed in common so that they cannot be individually moved in the first direction. And a light irradiation method comprising the steps of:

Images