JP6070285B2 - Polarized light irradiation device - Google Patents

Description

  The invention of the present application relates to a polarized light irradiation apparatus used when performing photo-alignment or the like.

  In recent years, in the manufacture of display devices centering on liquid crystal displays, a technique called light distribution has been widely adopted. For example, a liquid crystal display has a built-in light distribution film that is a film for aligning the orientation of liquid crystal molecules, but a mechanical method called rubbing has been used to obtain the light distribution film. However, from the viewpoint of improving light distribution characteristics, etc., in recent years, many photo-alignment techniques for obtaining a light distribution film by irradiating the film with light have been adopted. In addition, a photo-alignment technique is also employed when obtaining a layer for viewing angle compensation that is generally required in a display device. Hereinafter, films and layers in which alignment is caused by light irradiation are collectively referred to as a photo-alignment film. Note that “orientation” or “orientation treatment” is to give directionality to some property of an object.

  When performing photo-alignment, it is carried out by irradiating polarized light onto a film for photo-alignment film (hereinafter, film material). The film material is made of resin such as polyimide, for example, and the film material is irradiated with polarized light polarized in a desired direction (direction to be oriented). By irradiation with polarized light having a predetermined wavelength, the molecular structure (for example, side chain) of the film material is aligned in the direction of the polarized light, and a photo-alignment film is obtained.

The photo-alignment film is increased in size from the viewpoint of increasing the size of the display device in which it is used and improving the productivity. In a liquid crystal display for TV, the photo-alignment film has to be larger due to an increase in the size of the panel, and even when many display devices are manufactured from a single glass substrate, the light alignment film is adapted to the substrate size. The alignment film also tends to increase in size.
For example, in the recent polarized light irradiation apparatus for photo-alignment, the width of the irradiation region is 1500 mm or more. As a polarized light irradiation apparatus having such a wide irradiation region, for example, an apparatus described in Patent Document 1 has been proposed. The apparatus described in the above publication includes a rod-shaped light source having a length corresponding to the width of the irradiation area and a polarizing element unit that polarizes light from the light source, and is conveyed in a direction perpendicular to the longitudinal direction of the light source. The film material to be formed is irradiated with polarized light.

JP 2006-184747 A

  An important performance of the polarized light irradiation apparatus for photo-alignment is the uniformity of the polarization axis on the irradiated surface. If the polarization axis of the irradiated polarized light varies within the irradiation plane, the light orientation is not uniform, and display unevenness occurs in the manufactured display device. For this reason, the polarized light irradiation apparatus is required as one of the important characteristics that the polarization axis in the irradiation plane has high uniformity, that is, the variation in the direction of the polarization axis is suppressed as much as possible. ing.

However, when the photo-alignment film becomes larger and the irradiation area becomes wider as described above, the problem of variation in the polarization axis is likely to become obvious. According to the inventor's research, in the case of the polarized light irradiation apparatus using the rod-shaped light source as described above, it has been found that the variation in the polarization axis at both ends in the length direction in the irradiation region can be a significant problem.
The invention of the present application has been made on the basis of such knowledge, and in a polarized light irradiation apparatus using a rod-shaped light source, there is a problem of variations in polarization axes at both ends in the length direction of the light source even if the irradiation area becomes wider. The problem to be solved is to prevent the problem from occurring.

In order to solve the above problems, the invention according to claim 1 of the present application is
A light source that forms a long light-emitting section;
A first mirror extending in the length direction of the light emitting portion of the light source and covering the back of the light source;
A polarizing element unit that is disposed in front of the light source and polarizes light from the light emitting unit;
The polarizing element unit polarizes the light from the light source in the light receiving region extending in the length direction of the light emitting unit by one or a plurality of wire grid polarizing elements arranged in parallel.
Second mirrors are arranged at both ends in the length direction of the first mirror,
The light source is a rod-shaped lamp having sealing portions at both ends,
The second mirror has a shape having a notch, and the sealing portion of the light source is inserted through the notch,
The notch extends from the insertion part of the sealing part to the side opposite to the polarizing element unit,
Each of the second mirrors has a configuration in which light having a traveling direction component in the length direction of the light emitting unit among the light from the light emitting unit is folded back to reach the light receiving region of the polarizing element unit.
In order to solve the above problem, the invention according to claim 2 is the configuration according to claim 1, wherein the end of each second mirror on the polarizing element unit side is the polarization of the first mirror. It has a configuration that is closer to the polarizing element unit than the end on the element unit side.
In order to solve the above-mentioned problem, the invention according to claim 3 is the configuration according to claim 1 or 2 , wherein the second mirror is flush with the end face of the first mirror or inside the end face. It has the structure that it is arrange | positioned in position.
In order to solve the above problem, according to a fourth aspect of the present invention, in the configuration according to any one of the first to third aspects, the second mirror is formed at an end in the length direction of the first mirror. It has the structure of closing the made opening.

As will be described below, according to the first aspect of the present invention, variations in the polarization axis in the irradiation region are suppressed to a small level. Therefore, when performing the photo-alignment process, the in-plane uniformity of the process can be increased. For this reason, it can contribute to manufacture of the display device without a display nonuniformity. Since the variation in the polarization axis is likely to be manifested when a longer light source is used, the apparatus of the present invention is more suitable when it is necessary to irradiate a wider irradiation region with polarized light.
Further, each second mirror has a notch, and the sealing portion of the light source is inserted through the notch, so that the light can be folded back at a position closer to the light emitting portion. For this reason, the effect which suppresses the dispersion | variation in a polarization axis can be made higher.
Furthermore, since the notch extends from the insertion portion of the sealing portion to the side opposite to the polarizing element unit, the effect of suppressing polarization axis variation is not affected by the notch.
According to the second aspect of the invention, in addition to the above effect, the end of each second mirror on the side of the polarizing element unit is more polarizing element unit than the end of the first mirror on the side of the polarizing element unit. Therefore, the effect of suppressing the variation in the polarization axis can be further enhanced.
According to the invention described in claim 3 , in addition to the above effect, the second mirror is disposed flush with the end face of the first mirror or at a position inside the end face. The mirror can be further arranged at a position closer to the light emitting unit, and the effect of suppressing polarization axis variation can be further enhanced.

1 is a schematic perspective view of a polarized light irradiation apparatus according to a first embodiment of the present invention. It is a front cross-sectional schematic diagram of the polarized light irradiation apparatus shown in FIG. It is a side cross-sectional schematic of the polarized light irradiation apparatus shown in FIG. It is the perspective schematic which showed the 2nd mirror 6 in 1st embodiment. It is the figure which showed the result of the experiment which confirmed the variation improvement effect of the polarization axis by the 2nd mirror 6, (1) is a measurement result when not arranging the 2nd mirror 6, (2) is the 2nd mirror. It is a measurement result when 6 is arranged. It is the figure shown typically which showed the effect | action of the 2nd mirror 6, (1) is the perspective schematic diagram shown about the reason for which the dispersion | variation in a polarization axis arises, (2) showed the reason for the dispersion being suppressed. It is a front schematic diagram. It is a front cross-sectional schematic diagram of the polarized light irradiation apparatus which concerns on 2nd embodiment. FIG. 8 is a schematic side sectional view of the apparatus shown in FIG. 7. It is a figure which shows the result of the experiment which confirmed that the effect | action of suppressing the dispersion | variation in a polarization axis became high in 2nd embodiment. It is the side surface schematic which showed the principal part of the 3rd polarized light irradiation apparatus, (1) is front sectional schematic, (2) is side schematic. It is the isometric view schematic shown about attachment or detachment of the light source 1 in the apparatus of 1st embodiment.

Next, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described.
FIG. 1 is a schematic perspective view of a polarized light irradiation apparatus according to the first embodiment of the present invention, and FIG. 2 is a schematic front sectional view of the polarized light irradiation apparatus shown in FIG.
In the apparatus of the first embodiment, the irradiation target (workpiece) W of the polarized light is a film material for the photo-alignment film. Specifically, the workpiece W is a resin sheet, and is wound around a roll as shown in FIG. 1 and pulled out to the irradiation position of polarized light. Polarized light is irradiated in the process of transporting the roll-to-roll workpiece, and optical alignment processing is performed. In addition, the conveyance direction of the workpiece | work W is a horizontal direction. As shown in FIGS. 1 and 2, the polarized light irradiation apparatus according to the first embodiment includes a rod-shaped light source 1 that forms a long light emitting portion, a first mirror 2, and a polarizing element unit 3. Yes.

As shown in FIG. 1, the rod-shaped light source 1 is arranged so that the length direction is a horizontal direction perpendicular to the workpiece W conveyance direction. In this embodiment, since photo-alignment is performed by light in the ultraviolet region, a high-pressure mercury lamp, a metal halide lamp in which other metal is added to mercury, or the like is used.
The first mirror 2 is arranged so as to cover the light source 1 from behind, and improves the light utilization efficiency by turning the light from the light source 1 back toward the work W. Note that “behind” means the back when the side on which the workpiece W is positioned is the front side.

  In this embodiment, the first mirror 2 has a pair of elongated plates extending in the length direction of the light source 1. The pair of plate-like mirrors 2 are arranged symmetrically with respect to the slit while forming a slit above the light source 1. Each first mirror 2 has a curved cross-sectional shape as shown in FIG. 2, and a substantially bowl-shaped reflection region is formed by the two first mirrors 2. As shown in FIG. 2, the cross-sectional shape of the reflecting surface formed by the two first mirrors 2 forms a part of an ellipse in this embodiment. A cross-sectional shape that forms a parabola instead of an ellipse may be employed.

  Each first mirror 2 is held by a mirror holder (not shown) so as to maintain the above-described posture. Each first mirror 2 is made of glass with a reflective vapor deposition film or made of aluminum. As the vapor deposition film, there may be employed a film that transmits light on the long wavelength side such as infrared rays so as not to irradiate the work. Each of the first mirrors 2 is long as shown in FIGS. 1 and 2, but it may be equivalent to the long mirror 2 as shown in the figure by arranging small mirrors. .

  Such a light source 1 and each first mirror 2 are housed in a lamp house 4. An air cooling box 5 for cooling is provided at the upper part of the lamp house 4. A large number of ventilation openings 41 are formed on the upper surface of the lamp house 4, and the air cooling box 5 is attached so as to cover the ventilation openings 41. A cooling fan 52 is connected to the air cooling box 5 via a duct 51.

  In this embodiment, the polarizing element unit 3 is composed of a wire grid polarizing element 31. The wire grid polarizing element 31 is a polarizing element having a structure in which a fine lattice (wire grid) made of a striped dielectric material is provided on a transparent substrate. The material for forming the grid may be a conductor material or a semiconductor material. Linearly polarized light having an electric field component in the length direction of the wire grid is difficult to transmit through the transparent substrate, and linearly polarized light having an electric field component in the direction perpendicular to the length direction of the wire grid is easily transmitted through the transparent substrate. A large amount of polarized light having a polarization axis in a direction perpendicular to the length direction of the wire grid is irradiated on the irradiation region.

Since it is difficult to manufacture a large-sized wire grid polarizing element 31, a polarizing element unit 3 in which a plurality of polarizing elements 31 are arranged in a frame is used when obtaining a large polarized light irradiation region. For example, the polarizing element unit 3 is formed by arranging about 10 to 30 rectangular wire grid polarizing elements 31 having a size of about 100 mm × 100 mm in the length direction of the light source 1.
The plurality of polarizing elements 31 are arranged inside a unit frame (not shown) and are integrally held by the unit frame. The unit frame holds the polarizing elements 31 so that the aligned polarizing elements 31 are in a horizontal posture and are accurately parallel to the direction in which the light source 1 and the first mirror 2 extend. The polarizing element unit 3 is attached to the light exit of the lamp house 4 as shown in FIG.

  When the light source 1 is turned on, a part of the light from the light source 1 reaches each polarizing element 31 while being partially reflected by the first mirror 2. A large amount of polarized light that is polarized in a direction perpendicular to the length direction of the wire grid passes through the polarizing element 31, and this polarized light is irradiated onto the irradiation region. And when the workpiece | work W passes an irradiation area | region, it receives irradiation of this polarized light, and a photo-alignment process is performed.

  In the polarized light irradiation apparatus of such an embodiment, a device for preventing variation of the polarization axis at both ends in the length direction of the light source 1 is provided. Specifically, as shown in FIG. 2, the apparatus of the embodiment includes second mirrors 6 at the positions of both ends in the length direction of the first mirror 2. The second mirror 6 will be described with reference to FIGS. 3 is a schematic side sectional view of the polarized light irradiation device shown in FIG. 1, and FIG. 4 is a schematic perspective view showing the second mirror 6 in the first embodiment.

As shown in FIGS. 2 to 4, each second mirror 6 is a plate-like mirror and is arranged in a vertically upright posture. Each of the second mirrors 6 has a substantially rectangular shape as a whole, but has a notch 61 in a part thereof. As shown in FIGS. 3 and 4, the notch 61 has a U shape formed to extend downward from the center of the upper side.
The notch 61 is for inserting the sealing portion of the light source 1. The rod-shaped light source 1 is narrowed at both ends of a sealed body, and serves as a sealing portion 11. A base 12 is provided outside the sealing portion 11. Each of the second mirrors 6 is disposed in a state in which the portion of the sealing portion 11 is inserted through the notch 61. The width of the notch 61 is slightly wider than the width of the sealing portion 11.

  As shown in FIG. 4, the light source 1 is held with the base 12 at both ends placed on the support 7. This holding position is a position where the sealing portion 11 is inserted into the notch 61 of each second mirror 6 and the sealing portion 11 does not contact the edge of the notch 61. Moreover, each 2nd mirror 6 is being fixed to the base board 62 attached to the lamp house 4, and can be attached or detached as needed.

Such a second mirror 6 folds light having a direction component in the length direction of the light source 1 out of the light from the light source 1 to reach the polarization region. Thereby, the dispersion | variation in the polarization axis in an irradiation area | region is improved.
FIG. 5 is a diagram showing the results of an experiment confirming the polarization axis variation improving effect by the second mirror 6. In this experiment, the orientation of the polarization axis at each point in the irradiation region R was measured using the apparatus of the first embodiment. A high pressure mercury lamp is used as the light source 1, and the light emission length (indicated by D1 in FIG. 5) is about 1800 mm. The length D2 of the irradiation region R is about 1500 mm, and the width W is about 80 mm. Such an irradiation region R was irradiated with polarized light by the wire grid polarizing element 31. In this experiment, the polarizing element 31 is arranged so that the wire grid extends in the long direction of the irradiation region R. Therefore, when the polarization is correctly performed, the polarization axes are aligned in the short direction of the irradiation region R. It becomes.

In the experiment, for comparison, the orientation of the polarization axis at each point in the irradiation region R was measured for both cases where the second mirror 6 was placed at both ends and where the second mirror 6 was not placed. FIG. 5A shows the measurement result when the second mirror 6 is not arranged, and FIG. 5B shows the measurement result when the second mirror 6 is arranged.
As shown in FIG. 5 (1), when the second mirror 6 is not arranged, the polarization axis varies at both ends, particularly corners, of the irradiation region R, and +0.62 with respect to the correct direction (short direction). It varies from about ° to -0.62 ° (variation width is about 1.24 °).
On the other hand, when the second mirror 6 is arranged, the variation of the polarization axis at the corner is about + 0.43 ° to −0.43 ° (variation width of about 0.86 °). It was confirmed that the variation in the axis was kept small.

  The reason why the variation in the polarization axis is improved by the second mirror 6 will be described with reference to FIG. FIG. 6 is a diagram schematically showing the operation of the second mirror 6, (1) is a schematic perspective view showing the reason why the polarization axis varies, and (2) suppresses the variation. It is the front schematic diagram shown about the reason.

  In the wire grid polarization element 31, generally, the polarization action is sufficiently exerted with respect to light incident perpendicularly to the transparent substrate. That is, the linearly polarized light L1 having an electric field component in a direction perpendicular to the wire grid 32 is transmitted through the transparent substrate, while the linearly polarized light L2 having an electric field component in a direction parallel to the wire grid 32 is transmitted through the transparent substrate. Reflected or absorbed without being able to. At this time, polarized light having an electric field component in an oblique direction with respect to the wire grid 32 can pass through the transparent substrate to some extent. Therefore, when a large amount of polarized light having an electric field component in an oblique direction enters the polarizing element 31, it leads to variations in the polarization axis on the irradiation surface. In addition, since the so-called superposition principle holds for the irradiation state of the polarized light on the irradiation surface, the direction of the polarization axis observed at a certain point is obtained by superimposing the polarization axes of each polarized light irradiated on that point. It becomes. Usually, the amount of polarized light with a polarization axis perpendicular to the direction of the wire grid 32 is very large, and the amount of polarized light with the other polarization axes is small, so that the observed polarization axis is perpendicular to the direction of the wire grid 32. It will be something.

When irradiating polarized light to the irradiation region R shown in FIG. 6, in the light receiving region 30 of the polarizing element unit 3, there is no light incident obliquely at a position directly below the light source 1, but it is vertical or vertical. Since much light is incident at a close angle, the amount of polarized light having an oblique polarization axis is relatively very small. For this reason, in the irradiation region, there is no variation in the polarization axis P1 just below the light source 1, or even very small.
However, at the peripheral position away from the position immediately below the light source 1, the amount of the light L3 incident obliquely with respect to the polarizing element 31 increases, so that the polarization axis P2 tends to vary. In particular, at the corner position, the amount of the light L3 incident obliquely with respect to the polarizing element 31 is relatively large, so that the variation of the polarization axis P2 becomes large. FIG. 5A shows such a phenomenon.

  On the other hand, when the second mirror 6 is arranged, as shown in FIG. 6B, the second mirror 6 reflects the light traveling outward (from the base 12) from the light emitting unit 10 of the light source 1. For this reason, when the second mirror 6 is not disposed, the light L 4 that has not entered is reflected by the second mirror 6 and enters the polarizing element 31. As a result, although the oblique light L3 is incident on the corner portion of the polarization element unit 3, the light L4 in a line-symmetric direction with respect to the light L3 also enters. Line symmetry means symmetry with respect to the reflection surface of the second mirror 6, and is a direction perpendicular to the wire grid 32 in the example of FIG. Due to the incidence of such light in the oblique direction with the line symmetry, the polarized light on the oblique polarization axis is superimposed on the polarized light with the oblique polarization axis on the irradiation surface and is canceled out. Polarized light having a polarization axis perpendicular to the wire grid appears dominant. For this reason, the variation of the polarization axis at the corner is suppressed to be very small. That is, as shown in FIG. 6 (2), the second mirror 6 projects the virtual image 10 ′ of the light emitting unit 10 of the light source 1 on the same straight line, and the light L4 is incident on the polarizing element 31 by the virtual image 10 ′. Acts to cancel the influence of the obliquely incident light L3.

  For the above-described operation, the second mirror 6 is preferably arranged at a position as close as possible to the light emitting unit 10 of the light source 1. Since the light is more diffused at the position away from the light emitting unit 10, even if the light is reflected at that position, the action of canceling the influence of the oblique incident light is weakened. In the apparatus according to the embodiment, the configuration in which the notch 61 is provided in the second mirror 6 and the sealing portion 11 of the light source 1 is inserted therein is arranged at a position closer to the light emitting portion 10. In addition, it has an important significance to further increase the effect of suppressing polarization axis variation.

  As described above, in the apparatus of the embodiment, the variation in the polarization axis in the irradiation region is suppressed to be small, so that the in-plane uniformity of the photo-alignment process is increased. For this reason, it can contribute to manufacture of the display device without a display nonuniformity. The variation of the polarization axis is likely to be manifested when the longer light source 1 is used (in the case of a wider irradiation region) corresponding to the increase in the size of the photo-alignment film. It becomes more suitable when obtaining a film.

Next, the polarized light irradiation apparatus of the second embodiment will be described. FIG. 7 is a schematic front sectional view of a polarized light irradiation apparatus according to the second embodiment, and FIG. 8 is a schematic side sectional view of the apparatus shown in FIG.
The apparatus shown in FIGS. 7 and 8 is the same as the first embodiment except that the second mirror 6 is different in dimension and shape from the first embodiment. In the first embodiment shown in FIGS. 1 to 3, the second mirror 6 is the same height as the first mirror 2, and the lower end of the second mirror 6 is the same height as the lower end of the first mirror 2. That was it. However, as shown in FIGS. 7 and 8, in the second embodiment, the second mirror 6 is higher than the first mirror 2 and the lower end is positioned lower than the first mirror 2. Yes. That is, the end of the second mirror 6 on the irradiation region side is closer to the polarizing element unit 3 than the end of the first mirror 2 on the polarizing element unit 3 side.

  As described above, when the second mirror 6 protrudes toward the polarizing element unit 3 with respect to the first mirror 2, the effect of suppressing the variation in the polarization axis can be further enhanced. That is, as described above, the variation in the polarization axis at the corner of the irradiation region is determined by the relative amount of obliquely incident light in the polarizing element 31. Since the obliquely incident light includes a lot of reflected light from the first mirror 2, the reflection surface of the second mirror 6 is made larger than the first mirror 2 so that more light is folded back. Then, the effect of suppressing the variation in the polarization axis by canceling the influence of the oblique incidence becomes higher.

FIG. 9 is a diagram illustrating a result of an experiment for confirming that the action of suppressing variation in polarization axis is increased in the second embodiment. In the experiment shown in FIG. 9, the irradiation region was irradiated with polarized light under the same conditions as the experiment showing the result in FIG. 6 except for the second mirror 6, and the direction of the polarization axis at each point was measured.
As shown in FIG. 9, in the second embodiment, the variation of the polarization axis is about + 0.27 ° to −0.27 °, which is about 0.54 °, and the variation can be further reduced. It could be confirmed.

Next, the polarized light irradiation apparatus of the third embodiment will be described. FIG. 10 is a schematic side view showing the main part of the third polarized light irradiation apparatus, (1) is a schematic front sectional view, and (2) is a schematic side view. The embodiment shown in FIG. 10 is also the same as the first embodiment except for the dimensional shape and arrangement of the second mirror 6.
As shown in FIG. 10, in the third embodiment, the second mirror 6 is flush with the end face of the first mirror 2. That is, the outer surface of the second mirror 6 (the surface opposite to the reflecting surface) is flush with the end surface of the first mirror 2.

As shown in FIG. 10 (2), the upper side portion of each second mirror 6 has a shape along a curve (ellipse or parabola) formed by the reflecting surface of the first mirror 2. Each of the second mirrors 6 is disposed so as to be fitted to the edges at both ends of the first mirror 2. Also in this embodiment, the lower end of the second mirror 6 protrudes slightly below the first mirror 2.
As can be seen from FIG. 9A, in the third embodiment, the second mirror 6 can be disposed at a position closer to the light emitting unit of the light source 1. For this reason, the light from the light emitting portion can be folded back at a position with less diffusion, and the action of suppressing the variation in the polarization axis can be further enhanced. Each second mirror 6 may enter the inner side (the center side of the light source 1) from the end face of the first mirror 2. In order to make the position closer to the light emitting part, each second mirror 6 may be arranged at a position entering inside.

In each of the embodiments described above, the shape and position of the notch 61 provided in the second mirror 6 has the significance of facilitating attachment / detachment of the light source 1 while suppressing variations in the polarization axis. Hereinafter, this point will be described.
FIG. 11 is a schematic perspective view showing attachment and detachment of the light source 1 in the apparatus of the first embodiment. Also in the second third embodiment, the detachable structure is the same as that shown in FIG.

  The attachment and detachment of the light source 1 is necessary when the light source 1 is replaced for a lifetime or other reasons. In the lamp house 4 shown in FIGS. 2 and 3, the pair of first mirrors 2 are provided so as to be lifted upward. When the light source 1 is exchanged, as shown in FIG. 11, the pair of first mirrors 2 are lifted upward, and then the caps 12 on both sides of the light source 1 are separated from terminals not shown. Then, as shown in FIG. 11, the light source 1 is pulled upward by holding the caps 12 at both ends, and is removed from the second mirror 6. The mounting of the light source 1 is the reverse procedure.

  As a structure in which the sealing portion 11 of the light source 1 is inserted in the second mirror 6, an opening (for example, a circular opening) may be considered instead of the notch 61. However, in this case, when the light source 1 is attached or detached, the light source 1 must be pulled out in the length direction, which is a very troublesome operation. Moreover, the space for the length of the light source 1 will also be needed. Furthermore, since the opening needs to have a size larger than the maximum cross-sectional area of the light source 1 (usually the cross-sectional area of the envelope), the area of the reflecting surface is reduced accordingly. The structure of each of the above embodiments does not have such a problem.

  In the second mirror 6, it is also conceivable that the notch 61 has a shape extending from the lower side. In this case, when the light source 1 is replaced, the light source 1 is pulled down after the base 12 is removed. Although such a structure may be used, the portion of the notch 61 in the second mirror 6 does not return light, so that the effect of suppressing variation in the polarization axis may be insufficient. When the notch 61 is formed above the height of the light source 1 as in each embodiment, the notch 61 does not substantially affect the polarization axis variation suppressing effect.

In each of the above embodiments, the rod-shaped light source 1 is used. However, the light source 1 is merely used as a long light-emitting portion, and a light emission equivalent to or close to a long light-emitting portion by arranging a plurality of point light sources. Even if it is the structure which comprises a part, this invention can be implemented. For example, the structure which arranged the point light source which consists of LED in a line can be considered.
Further, the direction of the wire grid of each polarizing element 31 in the polarizing element unit 3 is not limited to the long direction in the rectangular irradiation region as described above, but in the case of a short direction or an oblique direction such as a diagonal direction. There is also a possibility. In some cases, the plurality of polarizing elements 31 are arranged so that the directions of the wire grids are different from each other.

In each of the above embodiments, the workpiece W is a sheet-like one, and the one wound in a roll shape is drawn out and irradiated with polarized light. Things can be work W. In this case, a configuration in which the substrate is placed on the stage and irradiated with polarized light while moving the stage may be employed.
In each of the above embodiments, the light source 1 and the first mirror 2 are arranged horizontally. However, the light source 1 and the first mirror 2 are arranged vertically, and are configured to irradiate polarized light to an irradiation region set in a vertical plane. There is also a possibility.

DESCRIPTION OF SYMBOLS 1 Light source 10 Light emission part 11 Sealing part 12 Base 2 First mirror 3 Polarizing element unit 31 Wire grid polarizing element 4 Lamp house 5 Air-cooled box 6 Second mirror 61 Notch

Claims (4)

A light source that forms a long light-emitting section;
A first mirror extending in the length direction of the light emitting portion of the light source and covering the back of the light source;
A polarizing element unit that is disposed in front of the light source and polarizes light from the light emitting unit;
The polarizing element unit polarizes the light from the light source in the light receiving region extending in the length direction of the light emitting unit by one or a plurality of wire grid polarizing elements arranged in parallel.
Second mirrors are arranged at both ends in the length direction of the first mirror,
The light source is a rod-shaped lamp having sealing portions at both ends,
The second mirror has a shape having a notch, and the sealing portion of the light source is inserted through the notch,
The notch extends from the insertion part of the sealing part to the side opposite to the polarizing element unit,
Each of the second mirrors is a polarized light that folds light having a traveling direction component in the length direction of the light emitting part out of the light from the light emitting part to reach the light receiving region of the polarizing element unit. Irradiation device.   The end of the second mirror on the polarizing element unit side is closer to the polarizing element unit than the end of the first mirror on the polarizing element unit side. Polarized light irradiation device. 3. The polarized light irradiation apparatus according to claim 1, wherein the second mirror is disposed flush with an end face of the first mirror or at a position inside the end face. 4.   The polarized light irradiation apparatus according to claim 1, wherein the second mirror closes an opening formed at an end portion in a length direction of the first mirror.

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