JP6015810B2 - Light irradiation apparatus and light irradiation method - Google Patents

Description

  The present invention relates to a light irradiation apparatus and a light irradiation method, and more particularly, to a light irradiation apparatus and a light irradiation method that include two work stages that can reciprocate on the same axis and that alternately irradiate light on the work on the work stage. About.

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.
A light irradiation device used for photo-alignment includes a rod-shaped 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 a direction orthogonal to the longitudinal direction of the light source The polarized light is applied to the workpiece conveyed to the surface.

  As such a light irradiation apparatus, there exists a technique of patent document 1, for example. This technology employs a twin stage method, and includes a first stage capable of reciprocating between a first workpiece mounting position set on one side of the irradiation area and the irradiation area, and an irradiation area. A second stage capable of reciprocating between a second workpiece mounting position set on the other side and the irradiation region. The first stage and the second stage are alternately moved to the irradiation area, and the work on the stage is irradiated with light, thereby reducing the tact time compared to the case where only one stage is provided. To do.

JP 2014-174352 A

In the technique described in Patent Document 1, for the purpose of further reducing the tact time, the forward movement of the other stage (workpiece) is performed so that one stage follows the backward movement (movement returning from the irradiation area to the workpiece mounting position). The movement from the mounting position toward the irradiation area) may be started.
However, the moving speeds of the stages differ depending on whether each stage is moving within the irradiation area (while the polarized light is being irradiated) and when moving outside the irradiation area. Specifically, each stage can move at a high speed when moving outside the irradiation area and only transporting the workpiece. It may move at a low speed to obtain an exposure amount.

Therefore, simply by synchronizing the timing of the start of the backward movement of one stage and the timing of the start of the forward movement of the other stage, there is a possibility that interference occurs between the stages due to the above moving speed difference.
Then, this invention makes it a subject to provide the light irradiation apparatus and light irradiation method which can perform a light irradiation process efficiently, without making a stage interfere in a twin stage system.

In order to solve the above-described problem, one aspect of the light irradiation apparatus according to the present invention is a light irradiation apparatus that irradiates light onto a workpiece that passes through a preset irradiation region, and the first workpiece is placed thereon. The movement from the first standby position to the irradiation area between the first standby position set on one side of the irradiation area and the irradiation area on the transport axis passing through the irradiation area. A first stage that can be reciprocated as a forward movement and a second workpiece are placed, and on the transport axis, a second standby position set on the other side of the irradiation area and the irradiation area A second stage capable of reciprocating between the second standby position and the movement from the second standby position toward the irradiation area, and the first work and the second work alternately pass through the irradiation area. The first stage and The control unit that individually controls the movement of the second stage, and the rotation of the first stage and the second stage around the axis orthogonal to the stage surface are individually controlled, and the posture of the stage A rotation control unit that takes a posture during light irradiation, and the control unit moves the first stage and the second stage slower than a preset maximum moving speed in the irradiation region. Moving at a speed, moving the return path outside the irradiation area at the maximum movement speed, and controlling the outward path outside the irradiation area to move at a movement speed at which the distance between the stages does not fall below a preset closest distance, rotation control unit, the first stage and the second stage, before reaching the irradiation region from the respective standby positions, the rotation permitting position or stage the distance between the position of not less than the closest distance The interval between being forward movement, and the rotation is possible pivoting movement section.

In this way, a so-called twin stage method is adopted in which two stages on which workpieces are placed are provided and light is alternately irradiated to each workpiece. Thereby, the work exchange operation | work etc. in the other stage can be performed during the light irradiation to one stage. Therefore, tact time can be reduced and productivity can be improved as compared with the case where there is only one stage. In addition, since the stage moving in the outward direction outside the irradiation area is moved at a moving speed such that the distance between the stages does not fall below the closest distance, there is a moving speed difference between the first stage and the second stage. Even in this case, the stage can be moved to efficiently perform the light irradiation process without causing interference between the stages.
Furthermore, by providing the rotation control unit, for example, when irradiating the work with polarized light, the work irradiation direction can be set to a predetermined direction with respect to the polarization axis of the polarized light. Further, by performing the rotation control of the stage during the forward movement, it is possible to suppress an increase in tact time.

Further, in the light irradiation device, the rotation allowable position is a turn-back in which when the non-rotation control target stage by the rotation control unit is moving in the forward path, the non-rotation control target stage is switched from the forward movement to the backward movement. From the position, set to the standby position side of the rotation control target by the closest distance, and when the non-rotation control target stage is moving in the backward path, from the position of the non-rotation control target stage, the closest distance The rotation control target may be set on the standby position side.
As a result, it is possible to perform rotation control during forward movement while avoiding interference between stages.

In the light irradiation apparatus, the control unit may be configured such that one of the first stage and the second stage moves in the outward direction outside the irradiation region, and the other stage moves in the backward direction. When the distance between the stages is longer than the closest distance, the one stage is moved at the maximum moving speed, and when the distance between the stages is equal to or less than the closest distance, the one stage May be moved at the moving speed of the other stage.
In this way, the forward movement is made at a relatively high speed to a position where no interference between the stages occurs, and then the preceding movement stage is followed. Therefore, the irradiation area can be quickly reached while avoiding the interference between the stages. Therefore, the light irradiation process can be performed on the other work immediately after the light irradiation process is performed on one work, and the tact time can be further shortened.

Furthermore, in the above light irradiation apparatus, the control unit is configured such that one of the first stage and the second stage moves outward in the irradiation area and the other stage moves in the backward direction. The one stage may be moved following the other stage.
In this way, the stage that moves in the outward direction outside the irradiation area is moved at the same movement speed as the other stage, so even if there is a movement speed difference between the first stage and the second stage. Thus, interference between the stages can be surely prevented.

Furthermore, in the above-described light irradiation apparatus, the control unit may prohibit the forward movement of the other stage while one of the first stage and the second stage is moving forward. Good.
As a result, it is possible to start the forward movement of the other stage after one stage starts the backward movement, and it is possible to avoid the situation in which the two stages move together. Therefore, it is possible to reliably avoid interference between the stages.

In the above-described light irradiation device described above, while the first stage is forward moved, the closest relative folded position switches to backward movement from the forward movement of the first stage distance toward the set target stop position to the standby position side of the second stage, to start forward movement of the second stage, when the second stage has reached the target stop position, When the first stage is moving forward, the second stage may be stopped at the target stop position until the first stage starts moving backward.
Thus, when one stage is moving in the outward direction, the outward movement of the other stage is started, so that the light irradiation process for the two workpieces can be performed more efficiently.

In the above light irradiation apparatus, the distance between the stages may be set in the transport axis direction between the tip position in the forward movement direction of the first stage and the tip position in the forward movement direction of the second stage. It may be a distance.
Thus, since the distance between the tip positions in the forward movement direction of each stage is the inter-stage distance, there is a difference in the shape of each stage, the rotation angle around the axis orthogonal to the stage surface, etc. However, it is possible to perform stage movement control that avoids interference between stages.
Furthermore, in the above light irradiation apparatus, the light may be polarized light. Thus, the present invention can also be applied to a polarized light irradiation apparatus that irradiates a workpiece with polarized light and performs a photo-alignment process.
Moreover, in said light irradiation apparatus, you may irradiate the said light by both an outward movement and a backward movement with respect to said 1st workpiece | work and said 2nd workpiece | work. Thereby, a light irradiation process can be performed without wasting energy.

Furthermore, one aspect of the light irradiation method according to the present invention is a light irradiation method for irradiating light to a workpiece that passes through a preset irradiation region, wherein the first workpiece is placed and passes through the irradiation region. On the transport axis, it is possible to reciprocate between the first standby position set on one side of the irradiation area and the irradiation area as a forward movement from the first standby position toward the irradiation area. A first stage and a second workpiece are placed, and the second standby position set on the other side of the irradiation region and the irradiation region are set on the transport axis between the irradiation region and the second region. Individually, so that the first workpiece and the second workpiece alternately pass through the irradiation region through a second stage that can be reciprocated as a forward movement from the standby position toward the irradiation region. When controlling the first stage And the second stage moves in the irradiation area at a movement speed slower than a preset maximum movement speed, moves in a return path outside the irradiation area at the maximum movement speed, and travels outside the irradiation area. Is controlled so that the distance between the stages does not fall below the preset closest distance. In addition, before the first stage and the second stage reach the irradiation area from their respective standby positions, a section to a rotation allowable position where the distance between the stages is not less than the closest distance the while forward movement, and with the rotation capable pivoting movement section, of the first stage and the second stage, to individually control the rotation around the axis orthogonal to the stage surface The posture of the stage is the posture at the time of light irradiation.

  In this way, a so-called twin stage method is adopted in which two stages on which workpieces are placed are provided and light is alternately irradiated to each workpiece. Thereby, the work exchange operation | work etc. in the other stage can be performed during the light irradiation to one stage. Therefore, tact time can be reduced and productivity can be improved as compared with the case where there is only one stage. In addition, since the stage moving in the outward direction outside the irradiation area is moved at a moving speed such that the distance between the stages does not fall below the closest distance, there is a moving speed difference between the first stage and the second stage. Even in this case, the stage can be moved to efficiently perform the light irradiation process without causing interference between the stages. Furthermore, the light irradiation process can be performed by setting the direction of the workpiece in a predetermined direction with respect to the polarization axis of the polarized light. Further, by performing the rotation control of the stage during the forward movement, it is possible to suppress an increase in tact time.

  In the light irradiation apparatus of the present invention, in the twin stage system, the stage moving in the forward direction can be moved at a moving speed such that the distance between the stage and the other stage does not fall below the closest distance. Therefore, even if there is a movement speed difference between the first stage and the second stage, the light irradiation process can be performed efficiently without causing the stages to interfere with each other. Furthermore, it is possible to suppress an increase in tact time by performing stage rotation control during forward movement.

It is a schematic block diagram which shows the polarized light irradiation apparatus of this embodiment. It is a figure explaining the movement area of each stage. It is a figure explaining the distance between stages. It is a figure explaining the distance between stages. It is a flowchart which shows the stage speed control processing procedure 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 flowchart which shows the stage speed control processing procedure of 2nd embodiment. It is a figure explaining operation | movement of 2nd embodiment. It is a figure explaining operation | movement of 2nd embodiment. It is a figure explaining operation | movement of 2nd embodiment. It is a figure explaining operation | movement of 3rd embodiment. It is a figure explaining operation | movement of 3rd 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 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 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 coincides with the method (Y direction) orthogonal to the conveyance direction (X direction) of the workpiece W, and the conveyance direction (X direction) of the workpiece W. Are arranged side by side.

Hereinafter, specific configurations of the light irradiation units 10A and 10B will be described.
The lamp 11 is a long lamp, and its light emitting portion has a length corresponding to the width in the direction orthogonal to the conveying direction of the workpiece W. The lamp 11 is, for example, a high-pressure mercury lamp or a metal halide lamp obtained by adding another metal to mercury, and emits ultraviolet light having a wavelength of 200 nm to 400 nm.
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 conveyance unit 20 includes a first stage 21A and a second stage 21B that hold the workpiece W, respectively. These two stages 21A and 21B are flat stages that hold the workpiece W by suction using a method such as vacuum suction. 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. Further, the configuration is not limited to the configuration in which the workpiece W is sucked and held by a flat plate stage, and may be a configuration in which the workpiece W is sucked and held by a plurality of pins.

Further, the transport unit 20 includes two guides 22 extending along the moving direction of the stages 21A and 21B, and electromagnets 23A and 23B that configure the moving mechanism of the stages 21A and 21B as an example. Here, for example, a linear motor stage is employed as the moving mechanism. The linear motor stage moves by moving a moving body (stages 21A and 21B) by air on a flat platen provided with ferromagnetic convex poles in a grid pattern and applying magnetic force to the moving body. This is a mechanism for moving the moving body by changing the magnetic force between the body and the convex pole of the platen. As the moving mechanism, for example, a mechanism using a ball screw can be adopted.
As described above, the stages 21A and 21B are configured to be capable of reciprocating along the guide 22 that is a common transport shaft.

Further, the transport unit 20 includes θ moving mechanisms 24A and 24B capable of rotating the stages 21A and 21B in the θ direction (around the Z axis), respectively. That is, the stages 21A and 21B are mounted on the fixed bases 25A and 25B so as to be rotatable in the θ direction, and the rotation angles thereof are adjusted by the θ moving mechanisms 24A and 24B.
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.

FIG. 2 is a diagram for explaining the movement section of the stages 21A and 21B.
The first stage 21A is set on the other side of the irradiation region 15 from the substrate mounting position (first standby position) P11 which is the workpiece mounting position set on one side of the irradiation region 15 of the polarized light. The section up to the turn-back position P12 can be reciprocated. The second stage 21B sandwiches the irradiation region 15 from a substrate mounting position (second standby position) P21 that is a workpiece mounting position set on the opposite side of the substrate mounting position P11 across the irradiation region 15. Thus, it is possible to reciprocate the section to the folding position P22 set on the opposite side to the folding position P12.

  Here, for the first stage 21A, the movement from the substrate mounting position P11 to the turn-back position P12 is defined as the forward movement. Similarly, regarding the second stage, the movement from the substrate mounting position P21 toward the turn-back position P22 is referred to as an outward movement. Further, the substrate mounting position is a position for exchanging and aligning the substrate (work W) placed on the stage, and the turn-back position is the irradiation region 15 and the substrate mounting position of the other stage. This is the switching position between the forward movement of the stage and the backward movement that is set in between.

  For example, the X direction distance L1 of the moving section (P11 to P12) of the first stage 21A and the X direction distance L2 of the moving section (P21 to P22) of the second stage 21B are set to be approximately equal. Further, between the substrate mounting position of the first stage 21 </ b> A and the irradiation region 15, the second stage 21 </ b> B can pass through the irradiation region 15 regardless of the posture of the second stage 21 </ b> B by rotational movement in the θ direction. To secure space. Similarly, between the substrate mounting position of the second stage 21 </ b> B and the irradiation region 15, the first stage 21 </ b> A can pass through the irradiation region 15 regardless of the posture by the rotational movement in the θ direction. Secure the above space.

The basic operation of each stage 21A and 21B is as follows.
The first stage 21A is subjected to the work W replacement work and alignment work at the substrate mounting position P11. After the alignment is completed, the first stage 21A is rotated by the θ moving mechanism 24A. 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 first stage 21 </ b> A starts the outward movement toward the irradiation region 15. Then, when passing through the irradiation region 15 and reaching the turn-back position P12, the backward movement is started and returned to the substrate mounting position P11. At the substrate mounting position P <b> 11, the work W replacement operation and the alignment operation are performed again, and after the alignment is completed, the first stage 21 </ b> A starts moving toward the irradiation region 15 again. This operation is repeated.

  Similarly, in the second stage 21B, the work W is exchanged and the alignment work is performed at the substrate mounting position P21. After the alignment is completed, the second stage 21B is rotated by the θ moving mechanism 24B and starts moving toward the irradiation area 15. To do. The rotation angle of the second stage 21B at this time may be different from the rotation angle of the first stage 21A. Then, when the second stage 21B passes through the irradiation region 15 and reaches the turn-back position P22, the second stage 21B starts to move backward and returns to the substrate mounting position P21. This operation is repeated.

In addition, as a normal operation, each stage 21A and 21B has a relatively high moving speed during a forward movement from the substrate mounting position toward the irradiation region 15 and during a backward movement from the irradiation region 15 back to the substrate mounting position. Moving speed (maximum moving speed) V1 is set, and the moving speed in other areas (in the irradiation area 15 and between the irradiation area 15 and the folding position) is lower than the first movement speed V1. The second moving speed V2 is set.
The control unit 30 controls each unit of the transport unit 20 (see FIG. 1), which is a stage moving mechanism, so as to realize the above-described stage operation. At this time, the control unit 30 acquires the position information of the stages 21A and 21B from the linear scale 31 arranged in parallel with the transport axis, and calculates the speed information of the stages 21A and 21B based on the acquired position information. To do. Then, the control unit 30 calculates the target movement positions and target movement speeds of the stages 21A and 21B based on the acquired position information and the calculated speed information, and outputs them to each unit of the transport unit 20.

Further, the control unit 30 is configured so that the first stage 21A and the second stage 21B repeatedly move back and forth on the common transport shaft as described above so that the stages 21A and 21B do not interfere with each other. Control the moving speed.
Specifically, while one stage is moving forward, only the backward movement of the other stage is permitted and the forward movement is prohibited. In addition, while one stage is moving in the backward direction and the other stage is moving in the outward direction outside the irradiation area, the distance between stages in the X direction (La described later) is a closest distance (described later). The moving speed of the stage moving in the forward direction is controlled so as not to approach closer than L0).

Here, the closest distance L0 is a marginal distance that allows the subsequent stage to be stopped without causing interference between the stages even if the preceding moving stage is urgently stopped. This closest distance L0 can be set based on, for example, the first moving speed V1 that is the maximum moving speed.
Each stage 21A and 21B is configured to be rotatable in the θ direction as described above. Therefore, as shown in FIG. 3, the inter-stage distance La is equal to the most advanced position P13 in the forward direction of the first stage 21A (right direction in FIG. 3) and the forward direction of the second stage 21B (in FIG. 3). The distance in the X direction from the most advanced position P23 in the left direction).

Each stage 21A and 21B can individually control the rotation angle in the θ direction. As shown in FIG. 4, the first stage 21A and the second stage 21B may have different rotation directions. Also in this case, the distance between the most advanced position P14 in the outward direction of the first stage 21A and the most advanced position P24 in the outward direction of the second stage 21B is defined as the inter-stage distance La.
FIG. 5 is a flowchart showing a stage speed control processing procedure executed by the control unit 30. The process shown in FIG. 5 is a process executed when the control unit 30 controls the moving speed of the first stage 21A. For the process of controlling the moving speed of the second stage 21B, “first stage” and “second stage” in the following description are read as “first stage”. Since it is only necessary, description is omitted here.

First, in step S1, the control unit 30 determines whether or not the first stage 21A is moving in the backward direction. Here, the control unit 30 determines the position and moving direction of the first stage 21A based on the position information of the first stage 21A, and determines whether or not the first stage 21A is moving in the backward direction. judge.
If it is determined in step S1 that the first stage 21A is moving in the backward direction, the process proceeds to step S2. On the other hand, if it is determined that the first stage 21A is not moving in the backward direction, that is, is moving in the forward direction or is stopped at the substrate mounting position, the process proceeds to step S3.

  In step S2, the control unit 30 sets a target moving speed so as to normally operate the first stage 21A, and outputs this to the moving mechanism of the first stage 21A. That is, when the first stage 21A is moving in the forward direction toward the irradiation area 15 or in the backward movement returning from the irradiation area 15 to the substrate mounting position, the target movement speed is set to the first movement speed V1, In the other area, the target moving speed is set to the second moving speed V2. Then, the set target moving speed is output to the moving mechanism of the first stage 21A.

  In step S3, the control unit 30 determines whether or not the second stage 21B is moving forward. Here, the control unit 30 determines the moving direction of the second stage 21B based on the position information of the second stage 21B, and determines whether or not the second stage 21B is moving forward. . If it is determined that the second stage 21B is moving in the forward direction, the process proceeds to step S4. If it is determined that the second stage 21B is moving in the backward direction, the process proceeds to step S5. To do.

In step S4, the control unit 30 causes the first stage 21A to wait at the substrate mounting position. That is, the control unit 30 sets the target moving speed to 0 so as to stop the first stage 21A, outputs this to the moving mechanism of the first stage 21A, and then proceeds to step S9 described later.
In step S <b> 5, the control unit 30 determines whether or not at least a part of the first stage 21 </ b> A exists in the irradiation region 15. Then, when the first stage 21A exists in the irradiation region 15, the process proceeds to step S2, and when it exists outside the irradiation region 15, the process proceeds to step S6.

  In step S6, the control unit 30 determines whether the interstage distance La between the first stage 21A and the second stage 21B is longer than the closest distance L0. Here, the interstage distance La is an X-direction distance between the most advanced position in the forward direction of the first stage 21A and the most advanced position in the forward direction of the second stage 21B, as described above. The most advanced position in the forward direction of each stage is obtained by calculation based on the position of the stage, the stage size, and the rotation angle of the stage.

If the interstage distance La is longer than the closest distance L0, it is determined that the first stage 21A is normally operated, and the process proceeds to step S2, where the interstage distance La reaches the closest distance L0. If yes, the process proceeds to step S7.
In step S7, the control unit 30 calculates a distance (irradiation area arrival distance Lb) until the first stage 21A reaches the irradiation area 15, and compares the irradiation area arrival distance Lb with the closest distance L0. . Here, as shown in FIG. 6, the irradiation area reach distance Lb is the end position of the first stage 21A on the substrate mounting position side in the irradiation area 15 from the most advanced position in the forward direction of the first stage 21A. It is the distance to. This irradiation area reach distance Lb is such that Lb> when the most advanced position of the first stage 21A is located on the backward side (left side in FIG. 6) of the irradiation area 15 (left end position in FIG. 6). When the leading edge position of the first stage 21A is located on the forward side (right side in FIG. 6) from the entrance of the irradiation region 15, Lb = 0.

When the irradiation area arrival distance Lb is equal to or greater than the closest distance L0, the process proceeds to step S8. When the irradiation area arrival distance Lb is shorter than the closest distance L0, the process proceeds to step S2.
In step S8, the control unit 30 sets the target moving speed of the first stage 21A to the moving speed of the second stage 21B so that the first stage 21A follows the second stage 21B. Output to the moving mechanism of one stage 21A.
In step S9, the control unit 30 determines whether or not to end the drive control of the first stage 21A. When it is determined that the control is to be continued, the control unit 30 returns to step S1, and when it is determined that the control is to be ended. Then, the stage speed control process ends.

Hereinafter, the operation of the present embodiment will be described in detail with reference to FIGS.
In the polarized light irradiation apparatus 100, as shown in FIG. 6, the substrate replacement operation and the substrate alignment operation are performed on the first stage 21A in a state where the first stage 21A is stopped at the substrate mounting position P11. . When the alignment work is completed, the first stage 21A is ready to start the outward movement (No in step S1 in FIG. 5).
At this time, as shown in FIG. 6, when the second stage 21B is moving in the outward direction (Yes in step S3), the first stage 21A does not start the outward movement and waits at the substrate mounting position. (Step S4). Thereafter, when the second stage 21B reaches the turn-back position and starts the backward movement, the first stage 21A starts the forward movement. That is, the first stage 21A starts the forward movement in synchronization with the timing when the second stage 21B starts the backward movement.

On the other hand, when the first stage 21A is ready to start the outward movement, the second stage 21B starts the backward movement (No in step S3). The stage 21A starts the outward movement as it is.
The moving speed of the first stage 21A at the start of the forward movement is determined based on the interstage distance La and the irradiation region arrival distance Lb. For example, as shown in FIG. 7, when the interstage distance La is longer than the preset closest distance L0 (Yes in step S6), the first stage 21A performs normal operation (step S2). That is, the first stage 21A starts the forward movement at the relatively high first moving speed V1.

The second stage 21B moves at a relatively low second moving speed V2 until it completely passes through the irradiation region 15 on the return path. Therefore, when the first stage 21A starts the forward movement at the first movement speed V1, the first stage 21A gradually catches up with the second stage 21B.
Then, as shown in FIG. 8, when the interstage distance La reaches the closest distance L0 before the rear end portion (the most advanced position in the forward direction) of the second stage 21B enters the irradiation region 15, (step No in S6, Yes in step S7), the moving speed of the first stage 21A is reduced to the second moving speed V2 (step S8). As a result, the first stage 21A follows the second stage 21B while maintaining the interstage distance La at the closest distance L0.

Thereafter, as shown in FIG. 9, when the rear end portion (the most advanced position in the forward direction) of the second stage 21B enters the irradiation region 15, the irradiation region arrival distance Lb becomes shorter than the closest distance L0 (step). The operation of the first stage 21A is switched from the follow-up operation of the second stage 21B to the normal operation (Step S2). That is, the moving speed of the first stage 21A is accelerated so as to become the first moving speed V1.
At this time, since the second stage 21B is moving at a relatively low second moving speed V2 in the irradiation region 15, the first stage 21A is switched to the normal operation so that the two approach each other. The distance La is shorter than the closest distance L0 as shown in FIG.

However, when the first stage 21A reaches the irradiation region 15 (Yes in step S5), the moving speed is reduced to the second moving speed V2 (step S2). Therefore, both the first stage 21A and the second stage 21B move at the second moving speed V2, and the interference between them does not occur.
Thereafter, when the second stage 21B completely passes through the irradiation region 15, the second stage 21B accelerates to the first moving speed V1 and returns to the substrate mounting position. At this time, the first stage 21A continues to move within the irradiation region 15 at the second moving speed V2. After that, the first stage 21A shifts to the return path movement when it reaches the turn-back position, and performs the normal operation on the return path regardless of the position of the second stage 21B until it returns to the substrate mounting position.

  As described above, the polarized light irradiation apparatus according to the present embodiment includes two work stages (first stage 21A and second stage 21B) that can reciprocate on the same axis, and a substrate (workpiece) on the work stage. A so-called twin-stage method is employed in which polarized light is irradiated alternately to W). Thereby, the substrate exchange work in the other stage can be performed during the irradiation of the polarized light to the one stage. Therefore, tact time can be reduced and productivity can be improved as compared with the case where there is only one work stage.

  In addition, while one stage is moving in the forward direction, the start of the forward movement of the other stage is prohibited, and in synchronization with the timing when the one stage reaches the turn-back position and the backward movement is started, Since the forward movement is started, it is possible to avoid the situation in which the two stages move together, and it is possible to reliably avoid the interference between the stages. Further, since the forward movement of the other stage can be started so as to follow the backward movement of one stage, the tact time can be further shortened.

  Further, at this time, considering that there may be a moving speed difference between the first stage 21A and the second stage 21B, the outside of the irradiation region 15 depends on the position and moving speed of the stage moving in the return path. Controls the moving speed of the stage moving forward. That is, when the interstage distance La is longer than the preset closest distance L0, the stage moving forward is controlled to move at the first movement speed (maximum movement speed) V1, and the interstage distance La is When the closest distance is less than or equal to L0, control is performed so that the stage moving in the outward path moves the stage moving in the backward path at the same moving speed.

  Thereby, the stage that has started the outward movement moves at a relatively high first moving speed V1 until the interstage distance La reaches the closest distance L0, and the relatively low second moving speed V2 in the irradiation region 15. When the distance La between stages catches up with the stage moving in the backward direction and becomes the closest distance L0, the movement speed is switched to the second movement speed V2. Thereafter, the stage moving in the forward path follows the stage moving in the backward path while maintaining the interstage distance La at the closest distance L0. In this way, the stage that has started the outward movement can catch up with the stage moving in the backward direction at a high speed so that the interstage distance La does not fall below the closest distance L0. Therefore, immediately after the stage moving in the backward path passes through the irradiation area (depending on the closest distance L0, the stage moving in the backward path passes through the irradiation area), the stage moving in the forward path The irradiation area can be entered. Therefore, the optical alignment process can be performed efficiently without interference between the stages.

  Further, since the distance between the tip position of the first stage 21A in the forward movement direction and the tip position of the second stage 21B in the forward movement direction is the inter-stage distance La, each stage is shown in FIGS. As shown in FIG. 3, even when the respective components are rotationally moved in the θ direction, the interference between the stages can be appropriately avoided. Further, at this time, since the tip position in the forward movement direction of the stage is calculated based on the position and size of the stage and the rotation angle in the θ direction, the interstage distance La can be calculated appropriately.

(Second embodiment)
Next, a second embodiment of the present invention will be described.
In the second embodiment, in the first embodiment described above, the start of the forward movement of the other stage is prohibited while one stage is moving the forward path, whereas the other stage is The start of the forward movement is permitted.
FIG. 11 is a flowchart showing a stage speed control processing procedure executed by the control unit 30 in the second embodiment. The process shown in FIG. 11 is the same as that in FIG. 5 except that step S4 in FIG. 5 described above is replaced with step S11. Therefore, the same step numbers are assigned to portions that perform the same processing as in FIG. 5, and here, the portions that are different in processing will be mainly described.
In step S11, the control unit 30 first sets a target stop position of the first stage 21A. The target stop position is a position separated from the turn-back position P22 of the second stage 21B by a predetermined distance (for example, the closest distance L0) to the substrate mounting position side of the first stage 21A.

Next, the control unit 30 determines whether or not the position of the first stage 21A is closer to the substrate mounting position of the first stage 21A than the target stop position. And when it determines with it being a board | substrate mounting position side rather than a target stop position, the 1st stage 21A is moved toward a target stop position. The moving speed at this time is the first moving speed V1. On the other hand, when the first stage 21A has reached the target stop position, the first stage 21A is stopped at the target stop position.
In other words, in the present embodiment, as shown in FIG. 12, even when the second stage 21B is moving in the outward direction, the first stage 21A, when the alignment process is completed at the substrate mounting position, The forward movement can be started at the moving speed V1. However, the permitted section for the forward movement of the first stage 21A at this time is a section from the turn-back position P22 of the second stage 21B to the target stop position P15 separated by the closest distance L0.

Then, if the second stage 21B has started the backward movement before the first stage 21A reaches the target stop position P15, the same operation as in the first embodiment described above is performed. On the other hand, as shown in FIG. 13, even if the first stage 21A reaches the target stop position P15, if the second stage 21B is moving forward, the first stage 21A is at the target stop position P15. And wait until the second stage 21B starts moving backward.
After that, as shown in FIG. 14, when the second stage 21B reaches the turn-back position P22 and starts moving backward (No in step S3), the first stage 21A starts following the second stage 21B. (No in step S6, Yes in step S8). That is, the first stage 21A starts moving at the same moving speed (second moving speed V2) as the second stage 21B. Subsequent operations are the same as those in the first embodiment described above.

Thus, in the present embodiment, even when one stage is moving in the outward direction, the outward movement of the other stage can be started. Therefore, it is possible to perform the optical alignment process on the two workpieces W more efficiently. In particular, when the speed difference between the first moving speed V1 and the second moving speed V2 is relatively small, or when the substrate mounting position is set relatively far from the irradiation area, The fact that the other stage starts moving forward during light irradiation is effective when it is difficult for the other stage to catch up with one stage during the light irradiation.
In addition, when one stage is moving forward, the forward movement permission section of the other stage is set to a position separated from the folding position of the other stage by a predetermined distance to the substrate mounting position side of the one stage. To do. Therefore, it is possible to reliably prevent interference with the other stage moving in the forward path.

(Third embodiment)
Next, a third embodiment of the present invention will be described.
In the third embodiment, in the first and second embodiments described above, the stage is rotated in the θ direction at the substrate mounting position, and the forward movement is started after the rotation is completed. On the other hand, the forward movement is performed while the θ rotation operation is performed.
In the present embodiment, the θ rotation operation of the first stage 21A and the second stage 21B is the position during the forward movement before entering the irradiation region 15 and the interstage distance La that is equal to or greater than the closest distance L0 can be secured. It shall be carried out in It is assumed that the time required for the θ rotation operation is shorter than the time required for the stage to move from the substrate mounting position to the irradiation region 15.

For example, when the substrate mounting on the first stage 21A is completed at the substrate mounting position, the first stage 21A starts the forward movement while performing the θ rotation operation. At this time, as shown in FIG. 15, when the second stage 21B is moving in the forward direction, the section from the substrate mounting position to the target stop position P15 becomes the θ-rotatable section. Here, the target stop position P15 is a position separated from the turn-back position P22 of the second stage 21B by a predetermined distance (for example, the closest distance L0) to the substrate mounting position side of the first stage 21A.
If the first stage 21A reaches the target stop position P15 before the second stage 21B reaches the turn-back position P22, the first stage 21A stops at the target stop position P15 and performs the θ rotation operation. Do.
Here, whether or not the first stage 21A has reached the target stop position P15 depends on whether the vertex of the first stage 21A is closest to the second stage 21B by θ rotation has reached the target stop position P15. Judgment by whether or not. That is, it is determined that the first stage 21A has reached the target stop position P15 when the forward direction tip of the circle indicated by the two-dot chain line in FIG. 15 has reached the target stop position P15.

On the other hand, when the second stage 21B is moving in the backward direction when the substrate mounting of the first stage 21A is completed and the outward movement is started, as shown in FIG. 16, after the second stage 21B, The section from the end position (the most advanced position in the forward direction) to the position separated from the first stage 21A toward the substrate mounting position by the closest distance L0 is the section in which the first stage 21A can be rotated by θ.
In this case, the first stage 21A performs the θ rotation operation while moving in the forward direction at the first movement speed V1, which is a normal movement speed, until the interstage distance La becomes the closest distance L0. Then, when the interstage distance La becomes the closest distance L0, the θ rotation operation is performed while moving in the forward direction while maintaining the closest distance L0 at the same second moving speed V2 as that of the second stage 21B. Here, the calculation starting point of the inter-stage distance La is set to a position where the vertex of the first stage 21A is closest to the second stage 21B by θ rotation as described above.

The operation after the θ rotation operation of the first stage 21A is completed is the same as in the first and second embodiments described above.
Thus, in this embodiment, since the θ rotation operation is performed while moving in the forward direction, the tact time can be further shortened. In addition, since the θ rotation operation can be performed at a position where the two stages do not approach each other below the closest distance L0, it is possible to reliably prevent interference between the stages.

(Modification)
In each of the above embodiments, when one stage is moving in the forward direction and the other stage is moving in the backward direction, one stage catches up with the other stage and the inter-stage distance La reaches the closest distance L0. Thus, the case where one stage follows the other stage (moves at the same speed as the other stage) has been described, but the present invention is not limited to this. For example, it may be made to follow the other stage immediately after the start of the forward movement of one stage. As a result, the moving speed of one stage is controlled in accordance with the moving speed of the other preceding stage, and even if the moving speed of the other stage differs depending on the moving section, there is interference between the stages. It can be surely prevented from occurring. However, for the purpose of further shortening the tact time, the subsequent stage is moved to the maximum moving speed (first moving speed) until the interstage distance La becomes the closest distance L0 as in the above-described embodiments. It is preferable to move in V1).

In each of the above embodiments, the case where the interstage distance La is the distance between the most advanced position in the forward direction of one stage and the most advanced position in the forward direction of the other stage has been described. When the size of the workpiece W (substrate) is larger than the stage size, the inter-stage distance La is the inter-workpiece distance. Also in this case, the most advanced position in the forward direction of the workpiece W is set as a calculation base point of the inter-workpiece distance.
Further, in each of the above-described embodiments, the interstage distance La is the X-direction distance between the side in the forward direction of one stage and the side in the forward direction of the other stage (the distance of the portion closest in the X direction). It is good.

In each of the above embodiments, the case where the position and moving speed of each stage are acquired using the measurement result of the linear scale has been described. However, the position and moving speed of each stage are acquired using means other than the linear scale. May be.
Further, in each of the above embodiments, the case where the present invention is applied to a polarized light irradiation apparatus has been described, but the present invention is not limited to this. For example, the two stages have a configuration capable of reciprocating along the same axis, and the two stages are alternately conveyed from the standby position set on the same axis across the light irradiation area to the light irradiation area. If it is the light irradiation apparatus which has a structure, the effect similar to each said embodiment is acquired by applying this invention. Examples of such a light irradiation apparatus include a DI (direct image) exposure apparatus and an ultraviolet irradiation apparatus that performs thermosetting treatment from ultraviolet rays.

  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 ... guide, 23A, 23B ... electromagnet, 24A, 24B ... theta moving mechanism, 30 ... control unit, 31 ... linear scale, 100 ... polarized light irradiation device

Claims (12)

A light irradiation device for irradiating light to a workpiece passing through a preset irradiation region,
The first standby position is set between the first standby position set on one side of the irradiation area and the irradiation area on the transport axis on which the first workpiece is placed and passes through the irradiation area. A first stage capable of reciprocating as a forward movement from the movement toward the irradiation area,
A second workpiece is placed, and on the transport axis, between the second standby position set on the other side of the irradiation region and the irradiation region, from the second standby position to the irradiation region. A second stage capable of reciprocating as the forward movement is a movement toward
A controller that individually controls movement of the first stage and the second stage so that the first workpiece and the second workpiece alternately pass through the irradiation region;
A rotation control unit that individually controls the rotation of the first stage and the second stage about an axis orthogonal to the stage surface, and sets the posture of the stage to the posture at the time of light irradiation, and
The controller is
The first stage and the second stage move in the irradiation area at a moving speed slower than a preset maximum moving speed, and move in a return path outside the irradiation area at the maximum moving speed, Control the distance between the stages so that the distance between the stages is not less than the preset closest distance on the outbound path outside the irradiation area.
The rotation control unit
Before the first stage and the second stage reach the irradiation area from their respective standby positions, they travel in the forward direction through a section to a rotation allowable position where the distance between the stages does not fall below the closest distance. The light irradiation apparatus is characterized in that the rotation operation enabled section is possible during the rotation. The rotation allowable position is
When the stage that is subject to non-rotation control by the rotation control unit is moving in the forward path, the rotation control target standby position side from the turn-back position where the stage that is subject to non-rotation control is switched from the forward path movement to the backward path movement. Set to
2. When the non-rotation control target stage is moving in a backward path, the closest distance is set to the rotation control target standby position side from the position of the non-rotation control target stage. The light irradiation apparatus as described in. The controller is
When one of the first stage and the second stage is moving in the outward direction outside the irradiation area, and the other stage is moving in the backward direction,
When the distance between the stages is longer than the closest distance, the one stage is moved at the maximum moving speed, and when the distance between the stages is equal to or less than the closest distance, the one stage is moved to the other distance. The light irradiation apparatus according to claim 1, wherein the light irradiation apparatus moves at a moving speed of the stage. The controller is
When one of the first stage and the second stage is moving in the outward direction outside the irradiation area, and the other stage is moving in the backward direction,
The light irradiation apparatus according to claim 1, wherein the one stage is moved to follow the other stage. The controller is
While the first stage and one stage of the second stage is forward moved, according to any one of claims 1 to 4, characterized in that prohibiting forward movement of the other stage Light irradiation device. The controller is
While the first stage is forward moved, it is set to the standby position side of the closest distance the second stage with respect to the folded position to switch the homeward movement from the forward movement of the first stage The second stage starts moving forward toward the target stop position,
When the second stage reaches the target stop position, when the first stage is moving forward, the second stage is moved until the first stage starts moving backward. It stops at a stop position, The light irradiation apparatus of any one of Claims 1-4 characterized by the above-mentioned. The distance between the stages is
Any of claims 1-6, characterized in that said the tip position in the forward movement direction of the first stage, which is the distance of the conveying direction between the tip position in the forward direction of movement of the second stage The light irradiation apparatus of Claim 1. Light irradiation apparatus according to any one of claims 1 to 7, wherein the light is polarized light. The light irradiation apparatus according to any one of claims 1 to 8 , wherein the light is irradiated to both the first work and the second work in both forward and backward movements. A light irradiation device for irradiating light to a workpiece passing through a preset irradiation region,
The first standby position is set between the first standby position set on one side of the irradiation area and the irradiation area on the transport axis on which the first workpiece is placed and passes through the irradiation area. A first stage capable of reciprocating as a forward movement from the movement toward the irradiation area,
A second workpiece is placed, and on the transport axis, between the second standby position set on the other side of the irradiation region and the irradiation region, from the second standby position to the irradiation region. A second stage capable of reciprocating as the forward movement is a movement toward
A controller that individually controls the movement of the first stage and the second stage so that the first workpiece and the second workpiece alternately pass through the irradiation region;
The controller is
While one stage of the first stage and the second stage is moving in the outward direction, the other stage is moved by the closest distance with respect to the turn-back position at which the one stage switches from the outward movement to the backward movement. Toward the target stop position set on the standby position side of the other stage, the forward movement of the other stage is started,
When the other stage reaches the target stop position, when the one stage is moving in the forward direction, the other stage is stopped at the target stop position until the one stage starts moving backward. The light irradiation apparatus characterized by doing. A light irradiation method for irradiating light to a workpiece passing through a preset irradiation region,
The first standby position is set between the first standby position set on one side of the irradiation area and the irradiation area on the transport axis on which the first workpiece is placed and passes through the irradiation area. A second stage that is set on the other side of the irradiation area on the transport axis, and a first stage that can reciprocate as a movement toward the irradiation area from the second stage. A second stage that is capable of reciprocating between the standby position and the irradiation area as a forward movement from the second standby position toward the irradiation area, the first work and the second work Are individually controlled to alternately pass through the irradiation area,
The first stage and the second stage move in the irradiation area at a moving speed slower than a preset maximum moving speed, and move in a return path outside the irradiation area at the maximum moving speed, Control the distance between the stages so that the distance between the stages is not less than the preset closest distance on the outbound path outside the irradiation area.
Before the first stage and the second stage reach the irradiation area from their respective standby positions, the section travels to a rotation allowable position where the distance between the stages does not fall below the closest distance. the while traveling, and with the rotation capable pivoting movement section, of the first stage and the second stage, to individually control the rotation around the axis orthogonal to the stage surface, A light irradiation method characterized in that the posture of the stage is a posture at the time of light irradiation. A light irradiation method for irradiating light to a workpiece passing through a preset irradiation region,
The first standby position is set between the first standby position set on one side of the irradiation area and the irradiation area on the transport axis on which the first workpiece is placed and passes through the irradiation area. A second stage that is set on the other side of the irradiation area on the transport axis, and a first stage that can reciprocate as a movement toward the irradiation area from the second stage. A second stage that is capable of reciprocating between the standby position and the irradiation area as a forward movement from the second standby position toward the irradiation area, the first work and the second work Are individually controlled to alternately pass through the irradiation area,
The first stage and the second stage move in the irradiation area at a moving speed slower than a preset maximum moving speed, and move in a return path outside the irradiation area at the maximum moving speed, Control the distance between the stages so that the distance between the stages is not less than the preset closest distance on the outbound path outside the irradiation area.
While one stage of the first stage and the second stage is moving in the outward direction, the other stage is moved by the closest distance with respect to the turn-back position at which the one stage switches from the outward movement to the backward movement. The forward movement of the other stage is started toward the target stop position set on the standby position side of
When the other stage reaches the target stop position, when the one stage moves in the forward direction, the other stage stops at the target stop position until the one stage starts moving backward. A light irradiation method characterized by:

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