TWI576188B - Light irradiation apparatus and drawing apparatus - Google Patents

Description

Light irradiation device and drawing device

The present invention relates to a light irradiation device and a drawing device.

Since the prior art, there has been proposed a technique of uniformly irradiating laser light emitted from a light source such as a semiconductor laser to a predetermined surface. For example, in a light irradiation device in which a laser beam incident from a light source portion is divided by a plurality of lenses in a cylindrical lens array, and an irradiation region of light from a plurality of lenses is superposed on an irradiation surface by another lens, An optical path length difference generating portion is provided between the light source portion and the cylindrical lens array. a plurality of light transmitting portions are disposed in the optical path length difference generating portion, and light passing through the plurality of light transmitting portions is respectively incident on the plurality of lenses, and the plurality of light transmitting portions mutually generate a coherence length relative to the laser light ( Interference distance) A longer optical path length difference. By this, it is possible to prevent the occurrence of the interference fringes, and to achieve the uniformity of the intensity distribution of the light that is irradiated onto the irradiation surface (for example, see Japanese Patent Laid-Open No. Sho 61-169815, Japanese Patent Laid-Open No. 2004-- Japanese Patent Publication No. 12757, Japanese Patent Laid-Open No. Hei. No. 2006-49656.

However, in order to realize the pattern drawing, a drawing device in which a spatial light modulator is disposed on the irradiation surface of the light irradiation device and the spatially modulated light is irradiated onto the object to draw a pattern is used. In order to increase the speed, a light irradiation device that can irradiate light having a uniform intensity distribution with high intensity to the irradiation surface is required.

The present invention is suitable for a light irradiation device, and its object is to provide a A high-intensity light having a uniform intensity distribution is irradiated to the light irradiation device to be irradiated.

The light irradiation device of the present invention is provided with: a light source unit having an arrangement a plurality of light source sections on one surface, wherein the plurality of light source sections emit laser light from different directions toward a predetermined position along the surface; and the illumination optical system is disposed at the predetermined position and is to be from the predetermined position The laser light of the light source unit is guided to the irradiation surface along the optical axis, and the illumination optical system includes a split lens unit having a plurality of lenses, and the plurality of light source units are used by the plurality of light sources The incident light is divided, the plurality of lens systems are arranged in a direction perpendicular to the optical axis and along the surface; the optical path length difference generating portion has a plurality of light transmitting portions and passes through the plurality of lenses The light is incident on the plurality of light transmitting portions, respectively, the plurality of light transmitting portions are arranged in a direction perpendicular to the optical axis and have mutually different optical path lengths; and the collecting lens portion is in the path of the laser light The light path length difference generating portion is disposed on the irradiation surface side, and the light irradiation region from the plurality of light transmitting portions is disposed on the irradiation surface Overlap.

According to the present invention, high intensity light having a uniform intensity distribution can be added To illuminate the illuminated surface.

In a preferred form of the invention, the light illumination device further has The intermediate magnification changing unit is disposed between the divided lens unit and the optical path length difference generating unit, and constitutes an enlarged optical system. In this case, it is preferable that the intermediate magnification portion constitutes a bilateral telecentric optical system. More preferably, the intermediate magnification portion is formed by forming an image of the exit surface of the plurality of lenses in or near the plurality of light transmitting portions.

In another preferred form of the invention, the illumination optical system is further Further, the reflector further includes a reflection portion that transmits the optical path length difference generating portion The light emitted from the plurality of exit surfaces of the plurality of light transmitting portions is folded back and incident on the plurality of exit surfaces. In this case, it is preferable that the reflection portion causes the light emitted from the plurality of emission surfaces to enter the plurality of emission surfaces so as to be parallel to the emission direction of the light.

In still another preferred embodiment of the present invention, the split lens portion and the upper portion are The optical path length difference generating portions are arranged to be close to each other, and the width of the light emitted from the exit surface of each of the plurality of light transmitting portions is smaller than the above in the direction in which the plurality of light transmitting portions are arranged The distance between the plurality of light transmitting portions.

The invention is also applicable to a rendering device. The drawing device of the present invention is provided The light irradiation device; the spatial light modulator disposed on the illumination surface of the light illumination device; and the projection optical system for guiding the spatially modulated light by the spatial light modulator a moving mechanism that moves the irradiation position of the spatially modulated light on the object; and a control unit that synchronizes with the movement of the irradiation position by the moving mechanism The way to control the above spatial light modulator.

The above and other objects, features, aspects and advantages of the present invention will become apparent from the accompanying drawings.

1‧‧‧Drawing device

4‧‧‧Light source department

5, 5a‧‧‧ illumination optical system

9‧‧‧Substrate

11‧‧‧Control Department

21‧‧‧ platform

22‧‧‧Mobile agencies

31, 31a‧‧‧Lighting device

32‧‧‧Space light modulator

33‧‧‧Projection optical system

39‧‧‧Mirror

40‧‧‧Light source unit

41‧‧‧Light source

42‧‧‧ Collimating lens

43‧‧‧稜鏡

44, 45, 632a, 632b‧‧ ‧ cylindrical lens

44a‧‧‧Spherical lens

46‧‧‧ Spatial Filter

50‧‧‧ illuminated area

53, 54, 332, 333, 643, 644, 657‧ ‧ lenses

55‧‧‧Polarized beam splitter

56‧‧‧1/4 wavelength plate

61‧‧‧ Optical path length difference generation unit

62‧‧‧ split lens section

63‧‧‧Concentrating lens unit

64a‧‧‧Intermediate zoom

65‧‧‧Reflection Department

320‧‧‧ illuminated surface

331‧‧ ‧ visor

334‧‧‧ aperture plate

335‧‧‧focus lens

461‧‧‧slit

610‧‧‧Transmission Department

611, 612‧‧‧ (transmission section) exit surface

613‧‧‧Mirror (reflecting surface)

620, 620a‧‧‧ component lens

621‧‧‧1st lens surface

622‧‧‧2nd lens surface

631‧‧‧ Concentrating lens

651a‧‧·Reflective film

658‧‧‧right angle

658a, 658b‧‧‧ 直角稜鏡

d _s ‧ ‧ Width of the gap in the Z direction between the second lens surface of the split lens portion and the incident surface of the optical path length difference generating portion

f _c , f _L ‧‧‧ focal length of cylindrical lens

J0, J1‧‧‧ optical axis

L _h ‧‧‧The length of the Z-direction of the component lens

P‧‧‧ arrangement spacing of component lenses (and light-transmitting parts)

p _o ‧‧‧width of the non-effective area in the X direction

P'‧‧‧ width of the effective area in the X direction

t _s ‧‧‧Maximum length of the light transmission section

t _so ‧‧‧ the difference between the lengths of the two light-transmitting portions adjacent to each other in the X direction

w _h ‧‧‧the width of the X-direction on the second lens surface of the light incident on the lens of each element from the light source portion

w _s ‧‧‧ The width of the beam in the X direction on the exit surface of the light-transmitting portion with the largest length in the Z direction

θ _i ‧‧‧incident angle (maximum incident angle)

θ _d ‧‧‧ divergence angle (half angle) of light passing through the concentrating point

θ' _d ‧‧‧ divergence angle (half angle) of the light inside the optical path length difference generating portion

Fig. 1 is a view showing the configuration of a drawing device according to the first embodiment.

Fig. 2 is a view showing the configuration of a light irradiation device.

Fig. 3 is a view showing the configuration of a light irradiation device.

4 is a view showing a part of a split lens unit and an optical path length difference generating unit.

Fig. 5 is a view showing the intensity distribution of light on the irradiation surface.

Fig. 6 is a view showing another example of the light irradiation device.

Fig. 7 is a view showing another example of the light irradiation device.

Fig. 8A is a view showing the intensity distribution of light on the irradiation surface.

Fig. 8B is a view showing another example of the light irradiation device.

Fig. 9 is a view showing the configuration of a light irradiation device according to a second embodiment.

Fig. 10 is a view showing the configuration of a light irradiation device according to a second embodiment.

Fig. 11 is a view showing the vicinity of a split lens unit.

Fig. 12 is a view showing another example of the light irradiation device.

Fig. 13 is a view showing another example of the light irradiation device.

Fig. 14 is a view showing another example of the light irradiation device.

Fig. 15 is a view showing another example of the light irradiation device.

Fig. 16 is a view showing another example of the optical path length difference generating portion.

Fig. 17 is a view showing another example of the light irradiation device.

Fig. 18 is a view showing another example of the light irradiation device.

Fig. 1 is a view showing the configuration of the drawing device 1 according to the first embodiment of the present invention. The drawing device 1 is a direct drawing device that draws a light beam on a surface of a substrate 9 such as a semiconductor substrate or a glass substrate to which a photosensitive material is applied, and draws a light beam. The drawing device 1 includes a stage 21, a moving mechanism 22, a light irradiation device 31, a spatial light modulator 32, a projection optical system 33, and a control unit 11. The platform 21 holds the substrate 9 and the moving mechanism 22 moves the platform 21 along the main surface of the substrate 9. The moving mechanism 22 can also rotate the substrate 9 around the axis perpendicular to the main surface.

The light irradiation device 31 illuminates the spatial light modulator 32 with linear light via the mirror 39. The details of the light irradiation device 31 will be described below. Space light The transformer 32 is, for example, a diffraction grating type and is of a reflective type, and is a diffraction grating that can change the depth of the grating. The spatial light modulator 32 is fabricated using semiconductor device fabrication techniques. The diffraction grating type optical modulator used in the present embodiment is, for example, a GLV (grating light value grating light valve) (registered trademark of Silicon Light Machines (Sunnyvale, California)). The spatial light modulator 32 has a plurality of grating elements arranged in a line, and each of the grating elements is switched between a state in which the diffracted light is emitted once and a state in which the diffracted light is emitted 0 times (0 times of light). In this manner, spatially modulated light is emitted from spatial light modulator 32.

The projection optical system 33 includes a light shielding plate 331, a lens 332, and a lens 333. A diagram plate 334 and a focus lens 335. The visor 331 partially shields the ghost light and the high-order diffracted light, and passes the light from the spatial light modulator 32. The lenses 332 and 333 constitute a varifocal portion. The aperture plate 334 shields (±1) times of diffracted light (and high-order diffracted light) and passes 0 times of diffracted light. Light passing through the aperture plate 334 is guided to the main surface of the substrate 9 by the focus lens 335. In this manner, the light that is spatially modulated by the spatial light modulator 32 is directed onto the substrate 9 by the projection optical system 33.

The control unit 11 is connected to the light irradiation device 31, the spatial light modulator 32, and The mechanism 22 is moved and its configuration is controlled. In the drawing device 1, the stage 21 is moved by the moving mechanism 22, and the light from the spatial light modulator 32 is moved at the irradiation position on the substrate 9. Further, the control unit 11 controls the spatial light modulator 32 in synchronization with the movement of the irradiation position by the moving mechanism 22. Thereby, the desired pattern is drawn on the photosensitive material on the substrate 9.

2 and 3 are views showing the configuration of the light irradiation device 31. Figure 2 In FIG. 3, the direction parallel to the optical axis J1 of the illumination optical system 5 is shown as the Z direction, and the direction perpendicular to the Z direction and orthogonal to each other is shown as the X direction and the Y direction (the same applies hereinafter). ). Figure 2 shows the light irradiation device observed along the Y direction The configuration of 31 shows the configuration of the light irradiation device 31 observed in the X direction.

The light irradiation device 31 shown in FIGS. 2 and 3 includes a light source unit 40, and The optical system 5 is illuminated. The light source unit 40 has a plurality of light source units 4, and each of the light source units 4 has one light source 41 and one collimator lens 42. The light source 41 of the plurality of light source units 4 is arranged on a plane parallel to the ZX plane (hereinafter referred to as a "light source array surface") and is arranged substantially in the X direction. The laser light emitted from each of the light sources 41 is collimated by the collimator lens 42 and incident on the illumination optical system 5. The light source unit 40 is provided with a mechanism (not shown) for adjusting the direction in which the laser light emitted from the light source unit 4 is emitted. By adjusting this mechanism, the X direction of the split lens unit 62 on the illumination optical system 5 that irradiates the laser light from the plurality of light source units 4 and the position of the irradiation surface 320 in the Y direction can be made coincident. In the light source unit 40, the plurality of light source units 4 arranged on the light source array surface face the same position on the illumination optical system 5 from the mutually different directions along the light source array surface (the divided lens portion described below) 62) Exit the laser light. Further, in the light source unit 40, a plurality of light source units 4 are attached to a support member (not shown), so that cooling of a plurality of light sources 41 and the like can be efficiently performed.

The illumination optical system 5 is a photo of the laser light disposed in the plurality of light source units 4 Shoot position. The illumination optical system 5 guides the laser light along the optical axis J1 to the surface of the spatial light modulator 32, which is an illumination surface (indicated by a broken line denoted by reference numeral 320 in FIGS. 2 and 3), that is, a plurality of grating elements. The surface. As described above, the light from the light irradiation device 31 is irradiated to the spatial light modulator 32 via the mirror 39. Therefore, the light irradiation device 31 actually includes the mirror 39 as a constituent element, but it is convenient for illustration. In Fig. 2 and Fig. 3, the mirror 39 (the same applies hereinafter) is omitted.

The illumination optical system 5 includes an optical path length difference generation unit 61 and a split lens unit. 62. The condensing lens unit 63. In the illumination optical system 5, the light source unit 40 is directed toward the irradiation surface 320, and the lens portion 62, the optical path length difference generation portion 61, and the condensing lens portion 63 are compliant. In this order, the configurations are arranged along the optical axis J1. The collimated laser light from the plurality of light source sections 4 is incident on the split lens section 62.

4 is a part of the split lens unit 62 and the optical path length difference generating unit 61. A diagram that is enlarged and represented. The split lens unit 62 includes a plurality of lenses 620 (hereinafter referred to as "element lenses 620") which are closely arranged at a fixed interval between the optical axis J1 perpendicular to the illumination optical system 5 and arranged along the light source. The direction of the face (here in the X direction). Each of the element lenses 620 is formed in a block shape that is long in the Y direction, and includes a first lens surface 621 that is located on the side of the (-Z) side (on the side of the light source unit 40), and a second lens surface 622 that is It is located on the side of the (+Z) side (the optical path length difference generating portion 61 side). When viewed in the Y direction, the first lens surface 621 is convex toward the (-Z) side, and the second lens surface 622 is convex toward the (+Z) side. When viewed in the X direction, the shape of each element lens 620 is rectangular (refer to FIG. 3). In this manner, the element lens 620 is a cylindrical lens having a magnification only in the X direction, and the divided lens portion 62 is a so-called cylindrical lens array (or a cylindrical fly-eye lens).

The first lens surface 621 and the second lens surface 622 are symmetrical with respect to a plane perpendicular to the optical axis J1. The first lens surface 621 is disposed at a focus of the second lens surface 622 , and the second lens surface 622 is disposed at a focus of the first lens surface 621 . In other words, the focal lengths of the first lens surface 621 and the second lens surface 622 are the same. The focal lengths of the first lens surface 621 and the second lens surface 622 are denoted by f _h , the refractive index of the element lens 620 is denoted by n _h , and the length L _{h of the} element lens 620 in the Z direction is expressed as (f _h ‧n _h ). The parallel light incident on the element lens 620 is condensed on the second lens surface 622. Further, when it is necessary to avoid damage or deterioration of the second lens surface 622 due to condensing, the length L _{h of the} element lens 620 in the Z direction may be a value slightly deviated from (f _h ‧ n _h ). The plurality of element lenses 620 laminated in the X direction may be formed as a unitary member, or a plurality of element lenses 620 formed separately may be joined to each other.

When viewed in the Y direction, it is incident on the split lens portion 62. The light is divided by the plurality of element lenses 620 in the X direction. At this time, parallel light from each light source unit 4 is incident on the first lens surface 621 of each element lens 620, and an image of a plurality of light sources 41 is formed in the vicinity of the second lens surface 622. The images are arranged in the direction in which the element lenses 620 are arranged. Furthermore, in FIG. 4, only the light rays incident on one element lens 620 are illustrated. The light (plurality of light beams) emitted from each of the light source units 4 and divided by the plurality of element lenses 620 is emitted from the second lens surface 622 such that the chief ray is parallel to the optical axis J1 (Z direction). The light beam emitted from each of the element lenses 620 is expanded on the one hand, and is incident on the optical path length difference generating portion 61 on the other hand.

The optical path length difference generating portion 61 is perpendicular to the optical axis J1 and has a plurality of transparent In the light portion 610, the light transmitting portions 610 are closely arranged at a fixed distance in a direction along the light source array surface (here, the X direction). In the example of FIG. 2, the number of the light transmitting portions 610 in the optical path length difference generating portion 61 is only one less than the number of the element lenses 620 in the split lens portion 62. Further, the arrangement pitch of the light transmitting portions 610 is equal to the arrangement pitch of the element lenses 620. Each of the light transmitting portions 610 (ideally) has a block shape perpendicular to the faces of the X direction, the Y direction, and the Z direction. In the plurality of light transmitting portions 610 which are lined up in the X direction, the lengths in the X direction and the Y direction are the same, and the Z direction is different from each other in the direction along the optical axis J1. In this manner, the plurality of light transmitting portions 610 have mutually different optical path lengths. In the optical path length difference generating portion 61 of FIG. 2, the length of the light transmitting portion 610 located on the (+X) side of the plurality of light transmitting portions 610 is smaller in the Z direction. The length of the plurality of light transmitting portions 610 in the optical axis J1 direction does not necessarily need to be lengthwise (or shortened) in the X direction, and may be any irregular shape. In the present embodiment, the plurality of light transmitting portions 610 in the optical path length difference generating portion 61 are formed of the same material to be integrally connected. In the optical path length difference generating portion 61, a plurality of individually formed light transmitting portions 610 may be bonded to each other.

The split lens portion 62 and the optical path length difference generating portion 61 are connected to each other in the Z direction. In the near-field arrangement, in the X direction, a plurality of element lenses 620 other than the element lens 620 closest to the (+X) side are disposed at the same position as the plurality of light transmitting portions 610, respectively. Therefore, a plurality of light beams that have passed through the element lenses 620 are incident on the plurality of light transmitting portions 610, respectively. Specifically, as shown in FIG. 4, the light beam emitted from the second lens surface 622 of each of the element lenses 620 is incident on the incident surface 611, and the incident surface 611 is disposed at the same position in the X direction. The surface of the light portion 610 on the (-Z) side. The light beam passes through the light transmitting portion 610 and is emitted from the exit surface 612 which is the surface on the (+Z) side. Furthermore, the light beam that passes through the element lens 620 on the most (+X) side does not pass through any of the light transmitting portions 610.

Actually, by dividing the lens portion 62 and the optical path length difference generating portion 61 The width of the light beam emitted from the exit surface 612 of each of the light transmitting portions 610 in the X direction is smaller than the width of the light transmitting portion 610, that is, the arrangement pitch of the light transmitting portions 610. Therefore, it is possible to prevent or suppress the light beam from entering the edge of the light transmitting portion 610 (i.e., the end portion in the X direction, mainly the edge of the incident surface 611 and the exit surface 612). Further, in the optical path length difference generating portion 61, the number of the light transmitting portions 610 which are the same as the number of the element lenses 620 in the split lens portion 62 may be provided. In this case, light passing through the plurality of (all) element lenses 620 is incident on the plurality of light transmitting portions 610, respectively.

As shown in FIGS. 2 and 3, the light beam that has passed through each of the light transmitting portions 610 faces the condensing lens portion 63. The condensing lens unit 63 has two cylindrical lenses 632a and 632b. The cylindrical lens 632a having a magnification of only the X-direction, and disposed from the plurality of second lens surface of the lens element 620 of the partition 622 in its degree of the focal length f _c of the (+ Z) side of the. In other words, the second lens surface 622 of each element lens 620 is disposed at the front focus position of the cylindrical lens 632a. Further, the irradiation surface 320 disposed on the axis line J1 from the cylindrical lens 632a is disposed on the (+ Z) side of the focal length of the cylindrical lenses 632a of the degree of f _c and the separated position. That is, the irradiation surface 320 is disposed at the rear focus position of the cylindrical lens 632a. The cylindrical lens 632b is disposed between the cylindrical lens 632a and the irradiation surface 320, and has a magnification only in the Y direction. The cylindrical lens 632b is disposed at a position separated from the irradiation surface 320 by the focal length f _L toward the (-Z) side.

As shown in Figure 2, when viewing in the Y direction, the number of elements The plurality of light beams emitted from the lens 620 are parallel light by the cylindrical lens 632a, and overlap on the irradiation surface 320. That is, the illumination regions 50 from the plurality of element lenses 620 (i.e., the plurality of beams passing through the plurality of light transmitting portions 610) all overlap. In FIGS. 2 and 3, the irradiation region 50 is indicated by a thick solid line, and the irradiation region 50 has a fixed width in the X direction. As described above, since the plurality of light beams emitted from the plurality of element lenses 620 pass through the mutually different light transmitting portions 610, a plurality of light beams generate an optical path length difference between the divided lens portion 62 and the irradiation surface 320. Therefore, it is possible to suppress (or prevent) the occurrence of interference fringes on the irradiation surface 320 due to the interference of the light split by the plurality of element lenses 620. That is, as shown in the upper part of Fig. 5, the intensity distribution of the light in the X direction becomes uniform on the irradiation surface 320. In each combination of the two light transmitting portions 610 of the plurality of light transmitting portions 610, it is preferable that the difference in the optical path lengths of the light beams passing through the two light transmitting portions 610 is the laser light emitted from the light source portion 4. Can be above the interference distance.

As shown in Figure 3, when viewed in the X direction, from the light source unit The light incident on the split lens unit 62 is maintained in parallel light and passes through the split lens unit 62, the optical path length difference generating unit 61, and the cylindrical lens 632a, and is guided to the cylindrical lens 632b. Then, the light emitted from the cylindrical lens 632b is condensed on the irradiation surface 320. Therefore, in the irradiation surface 320, the irradiation region 50 of the light from each element lens 620 has a linear shape extending in the X direction. Thereby, a set of light passing through the plurality of element lenses 620 can be obtained, that is, a cross section on the irradiation surface 320 (that is, a beam profile perpendicular to the optical axis J1, the same applies hereinafter) to become a linear line illumination extending in the X direction. Light. In the lower part of Fig. 5, the intensity distribution of the line illumination light in the Y direction is shown. In the light irradiation device 31, two cylindrical lenses 632a, 632b The function can also be realized by a spherical lens, or a spherical lens can be combined with a cylindrical lens.

As described above, in the light irradiation device 31 of FIG. 2, the laser light is emitted from the plurality of light source units 4 toward the split lens unit 62. Thereby, higher-intensity line illumination light can be obtained as compared with the light irradiation device using only one light source unit 4. Further, since the phases of the laser light from the plurality of light source units 4 are different from each other, it is possible to further improve the optical path length difference by the plurality of light beams passing through the plurality of element lenses 620 by the plurality of light transmitting portions 610. The uniformity of the intensity distribution of the line illumination light in the illumination surface 320. Further, according to the design of the light irradiation device 31, the width of the bright portion of the interference fringe in the irradiation surface 320 may be made by slightly shifting (defocusing) the irradiation surface 320 from the rear focus position of the cylindrical lens 632a. Expanded to reduce the contrast in the line illumination.

Here, a condition for more reliably preventing generation of interference fringes on the irradiation surface 320 will be described with reference to FIG. 4 . When the refractive index of the optical path length difference generating portion 61 is n _s and the difference between the lengths of the two light transmitting portions 610 adjacent to each other in the X direction in the Z direction is t _so , the two light transmitting portions The optical path length difference Δz _s in 610 is expressed by Equation 1. In the formula 1, the refractive index in the air is set to 1.

(Formula 1) Δz _s = (n _s -1) ‧ t _so

In the light irradiation device 31, by making the optical path length difference Δz _s equal to or greater than the interference distance L _c of the laser light emitted from the light source unit 4, that is, by satisfying Expression 2, it is possible to more reliably prevent the plurality of The interference of the light split by the element lens 620 causes interference fringes on the irradiation surface 320.

(Formula 2) L _c ≦(n _s -1)‧t _so

Further, since the interference between the optical path lengths of the light passing through the respective combinations of the two light transmitting portions 610 is larger, the interference can be reduced. Therefore, even if the difference in optical path length does not reach the laser light emitted from the light source portion 4 The interference distance can be reduced to some extent by a relatively long distance (for example, 1/2 or more of the interference distance). Therefore, the optical path length difference in each combination of the two light transmitting portions 610 can be appropriately set in accordance with the uniformity (contrast value) required for the intensity distribution of the line illumination light.

In addition, when the light passing through each of the element lenses 620 of the split lens portion 62 is incident on the edge of the light transmitting portion 610 (the boundary between the light transmitting portions 610, etc.) in the optical path length difference generating portion 61, the light is scattered. The uniformity of the intensity distribution of the light on the illuminated surface 320 is reduced. Therefore, a condition for preventing the light beam emitted from each element lens 620 from being incident on the edge of the light transmitting portion 610 will be described with reference to FIG.

As described above, in the light irradiation device 31, the number of the light transmitting portions 610 in the optical path length difference generating portion 61 is only one less than the number of the element lenses 620 in the divided lens portion 62 (see FIG. 2). Therefore, the number of the light transmitting portions 610 in the optical path length difference generating portion 61 is N _s , and the number of the element lenses 620 in the divided lens portion 62 is N _h , and the plurality of light transmitting portions are formed. The length t _s of the light transmitting portion 610 having the largest length in the Z direction in 610 is expressed by Formula 3.

(Equation 3) t _s =N _s ‧t _so =(N _h -1)‧t _so

On the other hand, the incident angle of the laser beam incident on the split lens unit 62 from the plurality of light source units 4 (the angle formed with respect to the Z direction when viewed in the Y direction) is incident on each element. The light of the lens 620 is attached to the second lens surface 622 which is the exit surface of the element lens 620, and is concentrated in the X direction from the optical axis J0 of the element lens 620 (indicated by a dotted line in FIG. 4). position. Specifically, the incident angle (maximum incident angle) of the light is θ _i , and the focal lengths of the first lens surface 621 and the second lens surface 622 are f _h , so that the light on the second lens surface 622 is The distance between the condensed spot and the optical axis J0 in the X direction is (f _h ‧ tan θ _i ). In the light irradiation device 31 of FIG. 2, since a plurality of light source portions 4 are arranged symmetrically with respect to a plane perpendicular to the X direction and including the optical axis J1 of the illumination optical system 5, the optical axis J0 of the element lens 620 is formed. Both the (+X) side and the (-X) side form a condensed spot separated by the same distance from the optical axis J0. Accordingly, since all the X-direction width of the light source unit 4 to the light incident on the lens elements 620 of the second lens surface 622 w _h line represented by the formula 4.

(Formula 4) w _h = 2f _h ‧ tan θ _i

Further, the divergent angle (half angle) θ _d of the light passing through the condensing point does not depend on the incident angle of the light from the light source unit 4, and the arrangement pitch of the element lens 620 (and the light transmitting portion 610) is arranged. Set to p, and express it to Formula 5.

(Equation 5) θ _d =tan ^-1 (p/2f _h )

The divergence angle (half angle) θ' _d of the light inside the optical path length difference generating portion 61 is expressed by Formula 6.

(Equation 6) θ' _d = sin ^-1 (sin θ _d /n _s )

Therefore, the width in the Z direction of the gap between the second lens surface 622 of the split lens portion 62 and the incident surface 611 of the optical path length difference generating portion 61 is d _s , and the light transmitting portion having the largest length in the Z direction is obtained. The width w _s of the light beam in the X-direction on the exit surface 612 of 610 is expressed by Equation 7.

(Expression 7) w _s =w _h +2(d _s ‧tanθ _d +t _s ‧tanθ' _d )

Actually, there is a case where the corner portion is removed from the light transmitting portion 610 and so-called chamfering is performed. In this case, in the exit surface 612 of the light transmitting portion 610, an ineffective region exists at the edge and its vicinity. The width of the non-effective area in the X direction is, for example, greater than 0 and 100 μm or less. The predetermined width of the non-effective area in the X direction is set to p _o , and the width p′ of the effective area on the exit surface 612 of the light transmitting portion 610 in the X direction is expressed by Formula 8.

(Equation 8) p'=p-2p _o

Therefore, the condition for preventing the light beam passing through each of the element lenses 620 of the split lens portion 62 from passing through the effective area of the exit surface 612 of the light transmitting portion 610 and preventing the light beam from scattering near the edge is expressed by Formula 9.

(Formula 9) w _s ≦p'

In the light irradiation device 31 of the formula 9, the light incident on the light transmitting portion 610 can be prevented from being incident on the edge of the light transmitting portion 610, so that the light irradiation device 31 can be more surely irradiated onto the irradiation surface 320. The uniformity of the intensity distribution of light. Moreover, the loss of the amount of light caused by the scattering of light at the edge of the light transmitting portion 610 can also be prevented. As described above, since the width p _{o of the} non-effective area in the X direction is larger than 0, it can be said that in the light irradiation device 31 satisfying the formula 9, the plurality of light transmitting portions are plural from the arrangement direction of the plurality of light transmitting portions 610. The width of the light emitted by the exit surface 612 of each of the 610 is less than the distance between the plurality of light transmitting portions 610.

Further, as is clear from Expressions 7 and 9, the smaller the maximum length t _{s of the} light transmitting portion 610, the easier it is to satisfy the condition shown in Formula 9. As described above, in the optical path length difference generating portion 61, the number of the light transmitting portions 610 which are the same as the number of the element lenses 620 in the split lens portion 62 may be provided. However, since the maximum length t _{s of the} light transmitting portion 610 depends on the number of the light transmitting portions 610, the number of the light transmitting portions 610 is preferably larger than that of the element lens from the viewpoint of easily satisfying the condition shown in the formula 9. The number of 620 is one less.

6 and 7 are views showing another example of the light irradiation device 31. Figure 6 The configuration of the light irradiation device 31 obtained as viewed in the Y direction is shown, and FIG. 7 shows the configuration of the light irradiation device 31 observed in the X direction.

In the light irradiation device 31 of FIG. 6, each light source unit 4 of the light source unit 40 In addition to the light source 41 and the collimator lens 42, the crucible 43, the cylindrical lens 44, and the cylindrical lens 45 are included. The light sources 41 of the plurality of light source units 4 are arranged in the X direction on the light source array surface parallel to the ZX plane. The laser light emitted from each of the light sources 41 is collimated by the collimator lens 42 and deflected by the crucible 43, and directed toward the split lens portion 62 of the illumination optical system 5. In the light source unit 40, the angle of the apex angle of the 稜鏡43 is changed according to the position of the plurality of light sources 41 in the X direction so as to be directed toward the illuminating optical system 5 from the mutually different directions along the light source arranging surface by the plurality of light source portions 4. The same position (divided lens portion 62) emits laser light. Further, in the light source unit 4 at the center in the X direction, the crucible 43 is omitted.

As shown in FIGS. 6 and 7, the cylindrical lenses 44, 45 have only the Y direction. Magnification. The cylindrical lenses 44, 45 are disposed between the crucible 43 and the split lens portion 62. The cylindrical lens 44 is provided for each light source unit 4, and the cylindrical lens 45 is shared by a plurality of light source units 4. A spatial filter 46 is provided between the cylindrical lens 44 and the cylindrical lens 45. The spatial filter 46 is a slit plate and forms a long slit 461 in the X direction. As shown in FIG. 7, when viewed in the X direction, the laser light passing through the cylindrical lens 44 is concentrated near the slit 461 of the spatial filter 46, and the light passing through the slit 461 is incident on the column. Face lens 45. The light that has passed through the cylindrical lens 45 is incident on the (-Z) side of the split lens portion 62.

The split lens unit 62 shown in FIGS. 6 and 7 is as shown in FIGS. 2 and 3 The division lens portion 62 is different in that the first lens surface 621 and the second lens surface 622 of each element lens 620a are each one of a spherical surface. In the split lens unit 62, the first lens surface 621 of the element lens 620a is disposed at the focus of the second lens surface 622, and the second lens surface 622 is disposed at the focus of the first lens surface 621. In other words, the focal lengths of the first lens surface 621 and the second lens surface 622 are the same. The structure and arrangement of the optical path length difference generating portion 61 are the same as those of the optical path length difference generating portion 61 of Fig. 2 .

As shown in FIG. 6, when viewed in the Y direction, the plurality of element lenses 620a divide the light incident on the split lens unit 62 in the X direction. The plurality of light beams that have passed through the plurality of element lenses 620a other than the element lens 620a closest to the (+X) side are incident on the plurality of light transmitting portions 610 of the optical path length difference generating portion 61, respectively. Light passing through the plurality of light transmitting portions 610 and light passing through the element lens 620a on the (+X) side are incident on the collecting lens portion 63. The condensing lens portion 63 has a condensing lens 631. The condensing lens 631 is disposed at a position separating the focal length f _c along the optical axis J1 from the second lens surface 622 (see FIG. 7) of the plurality of element lenses 620a. In other words, the second lens surface 622 of each element lens 620a is disposed on the front focal plane of the condensing lens 631. Further, the irradiation surface 320 disposed on the optical axis J1 is disposed at a position separating the focal length f _c of the condensing lens 631 from the condensing lens 631 along the optical axis J1. That is, the irradiation surface 320 coincides with the rear focal plane of the collecting lens 631. The plurality of light beams emitted from the plurality of element lenses 620a are parallel light by the condensing lens 631, and the side focal planes overlap behind the condensing lens 631. That is, the irradiation regions 50 of the light (plurality of light beams) from the plurality of element lenses 620a are all overlapped.

As shown in Figure 7, when viewed in the X direction, from the light source unit The light emitted from the cylindrical lens 45 of 40 is condensed on the first lens surface 621 of the plurality of element lenses 620a, and is emitted from the second lens surface 622 as parallel light parallel to the optical axis J1. The light from the plurality of element lenses 620a is condensed on the rear focal plane (irradiation surface 320) of the condensing lens 631 by the condensing lens 631. Thereby, the cross section on the irradiation surface 320 is obtained as linear line illumination light extending in the X direction.

As described above, in the light irradiation device 31 of FIG. 6, it is also possible to borrow The laser beam is emitted from the plurality of light source sections 4 toward the split lens section 62 to obtain high-intensity line illumination light. Further, by using the plurality of light source units 4, the optical path length difference is applied to the plurality of light beams passing through the plurality of element lenses 620a by the plurality of light transmitting portions 610, and the line illumination light in the irradiation surface 320 can be improved. Uniformity of intensity distribution. Further, in the light irradiation device 31 of FIG. 6, the emission surface 612 of each of the plurality of light transmission portions 610 may be emitted from the plurality of light transmission portions 610 in the arrangement direction of the plurality of light transmission portions 610 by satisfying the condition of Equation 9. The width of the light is less than the distance between the plurality of light transmitting portions 610. Thereby, it is possible to prevent the light incident on the light transmitting portion 610 from being incident on the edge of the light transmitting portion 610, and it is possible to more reliably ensure the uniformity of the intensity distribution of the light irradiated onto the irradiation surface 320 by the light irradiation device 31.

Figure 8A shows the intensity distribution of light in the Y direction on the illumination surface 320. Figure. In the case where it is assumed that the light source unit of the comparative example of the spatial filter 46 is omitted, there is a light that is necessary for the line illumination light in the intensity distribution of the Y direction light on the illumination surface depending on the type or state of the light source. The intensity peak, but the side lobe, etc. The intensity peak of the light that is needed. In Fig. 8A, intensity peaks of unwanted light are shown in dashed lines. On the other hand, in the light source unit 40 of FIG. 3, by providing the spatial filter 46, the intensity peak of the unnecessary light (that is, the light formed to be irradiated to the irradiation surface 320) can be removed, thereby achieving a better line. Lighting light.

In the light source unit 40 of FIG. 6, since a plurality of light source units 4 are attached to a support member (not shown), cooling of a plurality of light sources 41 and the like can be efficiently performed. Further, by using the crucible 43, the light source 41 and the collimator lens 42 can be disposed in all of the light source units 4 such that the optical axes of the light source 41 and the collimator lens 42 are parallel to the Z direction. As a result, the light source unit 40 of FIG. 2 in which the light source 41 and the collimator lens 42 are disposed at various angles with respect to the Z direction in the optical axes of the light source 41 and the collimator lens 42 in the plurality of light source units 4 is obtained. It is easier to make support components. Further, it is not necessary that the light is collimated in the X direction, and the light from the light source portion 4 may be slightly diverged or concentrated on the one hand and incident on the split lens portion 62 on the one hand. In Fig. 8B, a light irradiation device 31 that changes the cylindrical lens 44 of Fig. 6 into a spherical lens 44a is shown. The situation obtained by observing the light irradiation device 31 shown in Fig. 8B along the X direction is the same as that of Fig. 7.

Further, in the split lens unit 62 of FIG. 3 using the element lens 620 as the cylindrical lens, there is a case where the first lens is viewed in the X direction according to the accuracy of the production of the split lens unit 62. The deviation of the parallelism (wedge formation) of the lens surface 621 and the second lens surface 622 becomes larger in the plurality of element lenses 620. In this case, a plurality of light beams that have passed through the plurality of element lenses 620 are inclined toward mutually different directions with respect to the optical axis J1 to be incident on the condensing lens portion 63, thereby forming the irradiation surface 320. The position of the illuminated area 50 is offset in the Y direction. On the other hand, in the split lens unit 62 of FIG. 7, by using a spherical lens which is easily formed with high precision as the element lens 620a, the light beam passing through the plurality of element lenses 620a can be irradiated on the irradiation surface. The position at which the irradiation region 50 is formed on 320 is substantially uniform in the Y direction. The above method using each of the spatial filter 46, the crucible 43, and the element lens 620a can be employed alone in the other light irradiation device 31 (and the light irradiation device 31a described below).

9 and 10 are views showing a light irradiation device according to a second embodiment of the present invention. A diagram showing the structure of 31a. Fig. 9 shows the configuration of the light irradiation device 31a observed in the Y direction, and Fig. 10 shows the configuration of the light irradiation device 31a observed in the X direction.

The light irradiation device 31a shown in FIGS. 9 and 10 includes a light source unit 40, And the illumination optical system 5a. The light source unit 40 has the same configuration as the light source unit 40 of Fig. 2 . Therefore, in the light source unit 40, the plurality of light source units 4 emit laser light from the same position (the split lens unit 62 described below) on the illumination optical system 5a in a direction different from each other along the light source array surface.

The illumination optical system 5a includes an optical path length difference generation unit 61 and a split lens The portion 62, the condensing lens portion 63, and the intermediate magnification portion 64a. In the illumination optical system 5a, the light source unit 40 is directed toward the irradiation surface 320 in the order of the divided lens portion 62, the intermediate magnification changing portion 64a, the optical path length difference generating portion 61, and the collecting lens portion 63, and the like. The optical axis J1 is arranged. The collimated laser light from the plurality of light source sections 4 is incident on the split lens section 62. As shown in FIG. 11, in the split lens unit 62, a plurality of element lenses 620 are arranged in the X direction perpendicular to the optical axis J1 of the illumination optical system 5a and along the light source arrangement surface.

When viewed in the Y direction, it is incident on the split lens portion 62. The light is divided by the plurality of element lenses 620 in the X direction. At this time, parallel light from each light source unit 4 is incident on the first lens surface 621 of each element lens 620, and an image of a plurality of light sources 41 is formed in the vicinity of the second lens surface 622. The image lines are arranged in the direction in which the element lenses 620 are arranged. In addition, in FIG. 11, only the light rays incident on one element lens 620 are shown.

The light (multiple beams) split by the plurality of element lenses 620 is mainly light The line is emitted from the second lens surface 622 in a manner parallel to the optical axis J1. The light beam emitted from each of the element lenses 620 expands on the one hand, and enters the lens 643 of the intermediate magnification portion 64a shown in FIG. 9 on the one hand, and enters the optical path length difference generation portion 61 via the lenses 643 and 644. In the optical path length difference generating portion 61, a plurality of light transmitting portions 610 are arranged in the X direction perpendicular to the optical axis J1 of the illumination optical system 5a and along the light source array surface. The arrangement pitch of the light transmitting portions 610 is larger than the arrangement pitch of the element lenses 620.

The intermediate magnification portion 64a constitutes an afocal optical system, specifically, both sides The optical system of the heart is incident on the optical path length difference generating portion 61 in a state where the principal ray is incident parallel to the optical axis J1 in a state where the principal ray is parallel to the optical axis J1. At this time, the intermediate magnification changing unit 64a causes the image of the second lens surface 622 which is the exit surface of the plurality of element lenses 620 (in detail, the image of the plurality of light sources 41 in the second lens surface 622) to have an optical path length difference. The inside or the vicinity of the generating portion 61 is enlarged to be formed.

In detail, the magnification ratio and the optical path length are long by the intermediate magnification changing unit 64a. The arrangement pitch of the light transmitting portions 610 in the degree difference generating portion 61 is divided by the value obtained by dividing the arrangement pitch of the element lenses 620 in the divided lens portion 62. Therefore, the light (plurality of light beams) passing through the plurality of element lenses 620 is incident on the plurality of light transmitting portions 610 via the intermediate magnification changing portion 64a constituting the expanding optical system. At this time, the images of the second lens faces 622 of the plurality of element lenses 620 are formed inside or in the vicinity of the plurality of light transmitting portions 610, respectively. Further, the spread angle of the light beam emitted from each element lens 620 in the light transmitting portion 610 is smaller than the spread angle of the vicinity of the second lens surface 622 of the element lens 620 in accordance with the magnification factor. As a result, it is difficult for the light beam to strike the edge of the light transmitting portion 610 (for example, at the boundary with the adjacent light transmitting portion 610). The light beam that has passed through each of the light transmitting portions 610 faces the condensing lens portion 63. The plurality of light beams emitted from the plurality of light transmitting portions 610 are parallel light by the collecting lens 631 of the collecting lens portion 63, and are superposed on the irradiation surface 320. That is, the light from the plurality of light transmitting portions 610 (plurality of light beams) The shot areas 50 all overlap.

As shown in FIG. 10, when viewed in the X direction, the light system incident on the optical path length difference generating portion 61 from the light source unit 40 via the split lens portion 62 and the intermediate magnification portion 64a maintains the state of the parallel light. It passes through a plurality of light transmitting portions 610 and is guided to the collecting lens 631. Then, the light emitted from the condensing lens 631 is condensed on the irradiation surface 320. Therefore, in the irradiation surface 320, the light irradiation region 50 from each of the element lenses 620 (light transmitting portion 610) has a linear shape extending in the arrangement direction. In other words, the cross section of the light irradiated onto the irradiation surface 320 by the light irradiation device 31a becomes a line extending in the X direction, and line illumination light is obtained.

In the light irradiation device 31a, the condensing lens 631 is a spherical lens, but may be obtained in the irradiation surface 320 by, for example, adding a cylindrical lens having a magnification in the Y direction only to the condensing lens portion 63. Line illumination that becomes the desired width in the direction. Further, in the case where the light source 41 is a semiconductor laser of high magnification, it is preferable that when the laser light emitted from the light source 41 becomes multi mode in one direction, it becomes a single mode (single mode). The direction coincides with the direction (Y direction) perpendicular to the arrangement direction of the element lenses 620 in the split lens portion 62. Thereby, it is possible to prevent the width of the line illumination light in the Y direction from being enlarged on the irradiation surface 320.

Further, in the light irradiation device 31 shown in FIGS. 2 and 6, it is necessary to make the arrangement pitch of the light transmitting portions 610 in the optical path length difference generating portion 61 equal to the arrangement pitch of the element lenses 620 in the split lens portion 62. Although the small-sized split lens unit can be easily produced with high precision by using light lithography, it is difficult to use the light lithography for the optical path length difference generating portion in which the lengths of the plurality of light-transmitting portions in the optical axis direction are different from each other. . Therefore, it is necessary to produce an optical path length difference generating portion by a complicated operation such as machining.

On the other hand, in the light irradiation device 31a of FIG. 9, the intermediate magnification constituting the enlarged optical system is disposed between the split lens unit 62 and the optical path length difference generation unit 61. Part 64a. Thereby, in the arrangement direction of the light transmitting portion 610 (the X direction in FIG. 9), the optical path length difference generating portion 61 can be made larger than the split lens portion 62, and the optical path length difference generating portion 61 can be easily produced. In addition, in the light irradiation device 31 shown in FIG. 2 and FIG. 6, the intermediate magnification changing unit 64a is omitted, and the configuration can be simplified. Therefore, the size of the light irradiation device 31 can be easily reduced.

In the light irradiation device 31a, the plurality of light source units 4 are directed toward the split lens The portion 62 emits laser light. Thereby, higher-intensity line illumination light can be obtained as compared with the light irradiation device using only one light source unit 4. Further, since the phases of the laser light from the plurality of light source units 4 are different from each other, it is possible to further improve the optical path length difference by the plurality of light beams passing through the plurality of element lenses 620 by the plurality of light transmitting portions 610. The uniformity of the intensity distribution of the line illumination light in the illumination surface 320.

Further, in the light irradiation device 31a, the intermediate magnification changing unit 64a is used. An image of an exit surface of the plurality of element lenses 620 is formed inside or in the vicinity of the plurality of light transmitting portions 610, and as the image is enlarged, an expansion angle in the light transmitting portion 610 of the light beam emitted from each of the element lenses 620 becomes smaller than the image The angle of expansion in the element lens 620. As a result, it is possible to easily suppress the light beam from entering the edge of the light transmitting portion 610, and it is possible to more reliably ensure the uniformity of the intensity distribution of the light irradiated onto the irradiation surface 320 by the light irradiation device 31a.

12 and 13 are views showing another example of the light irradiation device 31a. Figure Reference numeral 12 denotes a configuration of the light irradiation device 31a observed in the Y direction, and Fig. 13 shows a configuration of the light irradiation device 31a observed in the X direction. The light irradiation device 31a shown in FIGS. 12 and 13 is different from the light irradiation device 31a of FIGS. 9 and 10 in that lenses 53 and 54 are added between the optical path length difference generating portion 61 and the collecting lens portion 63. different. The other configurations are the same as those of the light irradiation device 31a of FIGS. 9 and 10, and the same components are denoted by the same reference numerals.

The lenses 53, 54 constitute a reducing optical system (for example, a telecentric optical system on both sides) And an image of the second lens surface 622 of the plurality of element lenses 620 (see FIG. 11) inside or near the optical path length difference generating portion 61 (in detail, the plurality of light sources in the second lens surface 622) The image of 41) is used to reduce the relay. The light emitted from the lens 54 is incident on the condensing lens 631 of the condensing lens unit 63, and a linear irradiation region 50 is formed on the irradiation surface 320.

As described above, the light transmitting portion 610 of the light beam emitted from each of the element lenses 620 is as described above. The expansion angle is relatively small, whereby the light beam in the light irradiation device 31a can be easily suppressed from hitting the edge of the light transmitting portion 610. In this case, in order to obtain the line illumination light having a certain length in the X direction on the irradiation surface 320, it is necessary to provide the condensing lens 631 having a long focal length in the light irradiation device 31a of FIG. The entire length of the illumination optical system 5a in the direction becomes long. On the other hand, in the light irradiation device 31a of FIG. 12, the lenses 53 and 54 constituting the reduction optical system are provided between the optical path length difference generation portion 61 and the condensing lens portion 63, whereby the illumination optical can be realized. The overall length of the system 5a is relatively short, so that the miniaturization of the light irradiation device 31a can be achieved.

14 and 15 are views showing another example of the light irradiation device 31a. Figure Reference numeral 14 denotes a configuration of the light irradiation device 31a observed in the Y direction, and Fig. 15 shows a configuration of the light irradiation device 31a observed in the X direction. In addition to the light irradiation device 31a of FIGS. 9 and 10, a polarizing beam splitter 55, a quarter-wavelength plate 56, and a reflecting portion 65 are added to the light irradiation device 31a shown in FIGS. 14 and 15. The point is different. The other configurations are the same as those of the light irradiation device 31a of FIGS. 9 and 10, and the same components are denoted by the same reference numerals.

In the light irradiation device 31a of Fig. 14, from the (-Z) side toward the (+Z) direction, The reflection unit 65, the optical path length difference generation unit 61, the quarter-wavelength plate 56, the lenses 644 and 643 of the intermediate magnification change unit 64a, the polarization beam splitter 55, and the condensing lens unit 63 are arranged in this order. Composition. Further, the light source unit 40 is disposed on the (+X) side of the polarization beam splitter 55, and the split lens unit 62 is disposed between the light source unit 40 and the polarization beam splitter 55. In the light source unit 40, a plurality of light source units 4 arranged substantially in the Z direction emit laser light toward the split lens unit 62 in a direction parallel to the light source array surface and different from each other.

In the split lens portion 62, a plurality of element lenses 620 are arranged in a vertical direction The optical axis between the light source unit 40 and the polarization beam splitter 55 is along the Z direction of the light source array surface (see FIG. 11), and the light incident on the split lens unit 62 is divided in the Z direction. The light passing through the split lens portion 62 is incident on the polarization beam splitter 55 in a state where its chief ray is parallel to the X direction. The polarization beam splitter 55 separates the p-polarized component from the s-polarized component. The light that has entered the polarization beam splitter 55 from the light source unit 40 via the split lens unit 62 is almost an s-polarized component, and the light is reflected by the polarization beam splitter 55 toward the lens 643 of the intermediate magnification portion 64a. At this time, the arrangement direction of the plurality of light beams emitted from the plurality of element lenses 620 is converted into the X direction. In other words, the chief ray of the light from the polarizing beam splitter 55 toward the intermediate magnification portion 64a is parallel to the Z direction.

In the intermediate magnification portion 64a, a telecentric optical system on both sides is formed, and Light incident in a state where the principal ray is parallel to the optical axis J1 (Z direction) is incident on the optical path length difference generating portion 61 in a state where the principal ray is parallel to the optical axis J1. Actually, the light (plurality of light beams) passing through the plurality of element lenses 620 is incident on the plurality of light transmitting portions 610 arranged in the X direction via the polarization beam splitter 55, the intermediate magnification portion 64a, and the quarter wave plate 56, respectively. Thus, the image of the second lens surface 622 of the plurality of element lenses 620 (the image of the light source 41) is enlarged and formed inside or in the vicinity of the plurality of light transmitting portions 610 in the optical path length difference generating portion 61. In this manner, the arrangement direction of the element lenses 620 of the split lens portion 62 and the arrangement direction of the light transmission portions 610 of the optical path length difference generation portion 61 correspond to each other via the polarization beam splitter 55.

The reflecting portion 65 has a borrowing on the (-Z) side of the optical path length difference generating portion 61. A reflective film 651a formed by coating. The light beam incident on the incident surface 611 (see FIG. 4) which is the surface on the (+Z) side of each of the light transmitting portions 610 is reflected by the reflective film 651a on the exit surface 612 which is the surface on the (-Z) side, and The incident surface 611 is emitted. In other words, the light beam incident on the incident surface 611 of each of the light transmitting portions 610 reciprocates in the Z direction inside the light transmitting portion 610 and is emitted from the incident surface 611 in the (+Z) direction. The reflective film 651a on the exit surface 612 is substantially such that the light emitted from the plurality of exit surfaces 612 of the plurality of light transmitting portions 610 is folded back (that is, the traveling direction is rotated by 180 degrees) and is incident on the plurality of exit surfaces 612, respectively. . Further, the image of the second lens surface 622 of the element lens 620 is preferably formed in the vicinity of the emission surface 612 of the light transmitting portion 610 (near the reflection film 651a).

The light emitted from the optical path length difference generating portion 61 in the (+Z) direction passes through the 1/4 wave. The long plate 56 is incident on the intermediate magnification portion 64a. In the intermediate magnification changing portion 64a, the image of the exit surface of the plurality of element lenses 620 inside or near the optical path length difference generating portion 61 is reduced and relayed. Light emitted from the lens 643 is incident on the polarization beam splitter 55. The light incident from the intermediate magnification changing unit 64a to the polarization beam splitter 55 passes through the 1⁄4 wavelength plate 56 twice by the round trip between the polarization beam splitter 55 and the reflection unit 65, thereby becoming a p-polarized component, and Light is incident on the condensing lens 631 through the polarization beam splitter 55. Then, by the condensing lens 631, the irradiation region 50 of the light from the plurality of element lenses 620 is superposed on the irradiation surface 320.

As explained above, in the light irradiation device 31a of Fig. 14, in the partial In the course of the round trip of the light between the optical splitter 55 and the reflecting portion 65, the image obtained by expanding the exit surface of the plurality of element lenses 620 is formed in the plurality of light transmitting portions 610 by the intermediate magnification changing portion 64a. Internal or nearby. Thereby, in the arrangement direction of the light transmitting portions 610, the optical path length difference generating portion 61 can be made larger than the split lens portion 62, and the optical path length difference generating portion 61 can be easily produced. Moreover, since the functions of the lenses 53, 54 in FIG. 12 are realized by the intermediate magnification changing unit 64a in the return trip of the light round trip, the lens 53 can be omitted. Thus, the entire length of the light irradiation device 31a in the Z direction can be shortened. Further, the light beam that has passed through each of the light transmitting portions 610 reciprocates in the light transmitting portion 610, whereby the length of the optical path length difference generating portion 61 in the optical axis J1 direction can be shortened (for example, the optical path of FIG. 9 or FIG. 12 is set). Half of the length of the length difference generating portion 61).

Furthermore, in the light irradiation device 31a of Fig. 14, by using a polarized light The optical device 55 and the 1⁄4 wavelength plate 56 can reduce the amount of light relatively small. However, depending on the design of the light irradiation device 31, other beamsplitters such as a half mirror may be used. Further, the 1⁄4 wavelength plate 56 can be disposed at any position between the polarization beam splitter 55 and the reflection portion 65. The same is true for other light irradiation devices using the polarizing beam splitter 55 and the 1⁄4 wavelength plate 56. Further, in the light irradiation device 31a of Fig. 14, a mirror may be provided instead of the reflection film 651a. Further, the optical path length difference generating portion having the mirror (reflecting surface) 613 arranged in a stepped manner as shown in FIG. 16 may be used instead of the light transmitting type element as described above.

17 and 18 are views showing another example of the light irradiation device 31a. Figure 17 shows the configuration of the light irradiation device 31a observed in the Y direction, and FIG. 18 shows the configuration of the light irradiation device 31a observed in the X direction. In the light irradiation device 31a shown in Figs. 17 and 18, a lens 657 and a right angle 稜鏡 658 are provided instead of the reflection film 651a in the light irradiation device 31a of Figs. 14 and 15 . The other configurations are the same as those of the light irradiation device 31a of Figs. 14 and 15, and the same components are denoted by the same reference numerals.

The lens 657 of the reflecting portion 65 is disposed in the self-optical path length difference generating portion 61. The position where the image of the exit surface of the element lens 620 (see FIG. 11) is formed is separated by the focal length of the lens 657 toward the (-Z) side. Therefore, the light beam emitted from the exit surface 612 which is the surface on the (-Z) side of each of the light transmitting portions 610 toward the lens 657 is emitted as the parallel light toward the (-Z) side by the lens 657. The right angle 稜鏡 658 is disposed at a position separated from the lens 657 by the focal length of the lens 657 toward the (-Z) side. As shown in Figure 17, the situation observed in the Y direction At this time, each of the rays incident on the right angle 稜鏡 658 is reflected by one of the two faces 658a, 658b of 90 degrees toward the other face, and is further reflected by the other face, thereby being incident on the right angle 稜鏡 658. The path is directed parallel to the lens 657. The light incident on the lens 657 from the (-Z) side is concentrated on the one hand and incident on the optical path length difference generating portion 61. Actually, the light beam emitted from the exit surface 612 on the (-Z) side of each of the light transmitting portions 610 is folded back by the reflecting portion 65, and returns to the same surface to enter the emitting surface 612. Further, a light collecting point of the light beam is formed inside or near the light transmitting portion 610.

The light emitted from the optical path length difference generating portion 61 in the (+Z) direction passes through the 1/4 wave. The long plate 56 and the intermediate magnification portion 64a are incident on the polarization beam splitter 55. This light passes through the polarization beam splitter 55 and enters the collecting lens 631. Then, by the condensing lens 631, the irradiation region 50 of the light from the plurality of element lenses 620 is superposed on the irradiation surface 320.

Here, when it is observed in the X direction as shown in FIG. 18 The parallelism of the incident surface 611 and the exit surface 612 of the light transmitting portion 610 varies in each of the light transmitting portions 610. In this case, the light beam incident on the incident surface 611 on the (+Z) side of each of the light transmitting portions 610 as parallel light parallel to the optical axis J1 is from the exit surface 612 of the light transmitting portion 610 toward the optical axis J1. The oblique exit direction is emitted as parallel light. The light beam is concentrated by the action of the lens 657 at a position on the right angle 稜鏡 658 offset from the optical axis J1. The light beam reflected by the right angle 稜鏡 658 is parallel to the parallel direction of the outgoing direction by the lens 657 and is incident on the exit surface 612 of the light transmitting portion 610. Therefore, the light beam transmitted through the light transmitting portion 610 does not depend on the parallelism of the light transmitting portion 610, but is parallel to the path from the (+Z) side to the light transmitting portion 610 from the incident surface 611 (+Z) ) Directions. Further, the light irradiation region 50 from the plurality of light transmitting portions 610 is formed on the irradiation surface 320 at substantially the same position in the Y direction.

As described above, in the light irradiation device 31a shown in FIGS. 17 and 18, The reflecting portion 65 causes the light emitted from the exit surface 612 of each of the light transmitting portions 610 to be emitted parallel to the light. The direction is incident on the exit surface 612. Thereby, even when the parallelism (wedge formation) of the plurality of light transmitting portions 610 is deviated, the plurality of light beams emitted from the plurality of light transmitting portions 610 in the (+Z) direction can be made relative to the optical axis. The inclination of J1 (the inclination of the case as viewed in the X direction) coincides with the inclination (preferably parallel to the optical axis J1) when the (+Z) side is incident on the optical path length difference generating portion 61. As a result, it is possible to suppress or reduce the shift in the Y direction of the light collecting position (the condensing position when viewed in the X direction) of the plurality of light beams passing through the plurality of light transmitting portions 610 on the irradiation surface 320, thereby The increase in the width of the line illumination light on the irradiation surface 320 in the Y direction can be suppressed. Further, in the reflection portion 65, two rectangular mirrors or the like having an angle of 90 degrees with each other may be used instead of the right angle 稜鏡 658.

Various modifications can be made to the drawing device 1 and the light irradiation devices 31 and 31a described above.

In the split lens unit 62, it is not always necessary to arrange the plurality of element lenses 620 and 620a at a fixed interval in the arrangement direction. For example, the widths of the plurality of element lenses 620 and 620a in the arrangement direction may be different from each other. In this case, the width of the arrangement direction of the plurality of light transmitting portions 610 is also changed in such a manner that the width of each of the light transmitting portions 610 in the arrangement direction and the optical path length difference generating portion 61 corresponds to the transparency. The ratio of the widths of the element lenses 620 and 620a of the split lens portion 62 of the light portion 610 is fixed to all of the light transmitting portions 610.

The intermediate magnification portion 64a does not necessarily have to be a bilateral telecentric optical system, and may constitute an enlarged optical system in which light passing through the plurality of element lenses 620 and 620a is incident on the plurality of light transmitting portions 610, respectively.

In the path of the laser light in the light irradiation devices 31 and 31a, the condensing lens unit 63 disposed on the side of the irradiation surface 320 of the optical path length difference generating unit 61 is configured to allow light from the plurality of light transmitting portions 610. The irradiation region 50 is superposed on the irradiation surface 320, and can be realized by various configurations.

In the drawing device 1, the irradiation surfaces of the light irradiation devices 31 and 31a are disposed. The spatial light modulator 32 of 320 can be a light modulator other than a diffraction grating type optical modulator, for example, a spatial light modulator utilizing a collection of tiny mirrors can be used. In this case, an irradiation region in which the width in the Y direction is relatively wide may be formed on the irradiation surface 320 by the light irradiation devices 31 and 31a.

The moving mechanism for moving the irradiation position of the light on the substrate 9 may also be flat The moving mechanism other than the moving mechanism 22 that moves the table 21 may be, for example, a moving mechanism that moves the heads including the light irradiation devices 31 and 31a, the spatial light modulator 32, and the projection optical system 33 with respect to the substrate 9.

The object to be drawn by the drawing device 1 may be a semiconductor substrate or a glass substrate The substrate other than the glass substrate may be an object other than the substrate. The light irradiation devices 31, 31a can also be used to draw devices other than the device 1.

The configurations in the above-described embodiments and modifications are appropriately combined as long as they do not contradict each other.

The present invention has been described and illustrated in detail, but the foregoing description is illustrative and not restrictive. Therefore, it can be said that a plurality of variations or aspects can be employed without departing from the scope of the invention.

4‧‧‧Light source department

5‧‧‧Optical optical system

31‧‧‧Lighting device

40‧‧‧Light source unit

41‧‧‧Light source

42‧‧‧ Collimating lens

50‧‧‧ illuminated area

61‧‧‧ Optical path length difference generation unit

62‧‧‧ split lens section

63‧‧‧Concentrating lens unit

320‧‧‧ illuminated surface

610‧‧‧Transmission Department

620‧‧‧Component lens

632a‧‧‧ cylindrical lens

632b‧‧‧ cylindrical lens

f _c ‧‧‧ focal length of cylindrical lens

J1‧‧‧ optical axis

θ _i ‧‧‧incident angle (maximum incident angle)

Claims (7)

A light irradiation device comprising: a light source unit having a plurality of light source units arranged on one surface; and the plurality of light source units emitting laser light from different directions toward a predetermined position along the surface And an illumination optical system disposed at the predetermined position, and directing laser light from the light source unit to the illumination surface along an optical axis; the illumination optical system includes: a split lens portion having a plurality of lenses, and The light incident from the plurality of light source sections is divided by the plurality of lenses, the plurality of lens systems are arranged in a direction perpendicular to the optical axis and along the surface; and the optical path length difference generating portion has a plurality of light transmitting portions, and light passing through the plurality of lenses is incident on the plurality of light transmitting portions, respectively, and the plurality of light transmitting portions are arranged in a direction perpendicular to the optical axis and have mutually different optical path lengths a condensing lens unit disposed on the irradiation light surface in the path of the laser light, and the plurality of light transmissions from the plurality of light transmission lengths The irradiation area of light to be superimposed on the irradiation surface; and the intermediate magnification unit, which system is arranged between the split lens portion and the optical path length difference generating unit, and an optical system configured to expand. The light irradiation device of claim 1, wherein the intermediate magnification unit constitutes a telecentric optical system on both sides. The light irradiation device according to claim 2, wherein the intermediate magnification unit forms an image of an exit surface of the plurality of lenses in or near the plurality of light transmission portions. A light irradiation device comprising: a light source unit having a plurality of light source units arranged on one surface; and the plurality of light source units emitting laser light from different directions toward a predetermined position along the surface And an illumination optical system disposed at the predetermined position, and directing laser light from the light source unit to the illumination surface along an optical axis; the illumination optical system includes: a split lens portion having a plurality of lenses, and The light incident from the plurality of light source sections is divided by the plurality of lenses, the plurality of lens systems are arranged in a direction perpendicular to the optical axis and along the surface; and the optical path length difference generating portion has a plurality of light transmitting portions, and light passing through the plurality of lenses is incident on the plurality of light transmitting portions, respectively, and the plurality of light transmitting portions are arranged in a direction perpendicular to the optical axis and have mutually different optical path lengths a condensing lens unit disposed on the irradiation light surface in the path of the laser light, and the plurality of light transmissions from the plurality of light transmission lengths The irradiation area of the light is superimposed on the irradiation surface; and the reflection portion is configured to fold back the light emitted from the plurality of emission surfaces of the plurality of light transmission portions through the optical path length difference generation portion, and respectively enter the light The above plurality of exit faces. The light irradiation device of claim 4, wherein the reflection portion causes the light emitted from the plurality of emission surfaces to enter the plurality of emission surfaces so as to be parallel to the emission direction of the light. A light irradiation device comprising: a light source unit having a plurality of light source sections arranged on one surface, and the above a plurality of light source sections emit laser light from different directions toward a predetermined position along the surface; and an illumination optical system disposed at the predetermined position to guide the laser light from the light source unit along the optical axis The illumination optical system includes: a split lens unit having a plurality of lenses, and the light incident from the plurality of light source sections is divided by the plurality of lenses, wherein the plurality of lens systems are arranged a direction perpendicular to the optical axis and along the surface; an optical path length difference generating portion having a plurality of light transmitting portions, and light passing through the plurality of lenses is incident on the plurality of light transmitting portions, respectively The light transmitting portions are arranged in a direction perpendicular to the optical axis and have mutually different optical path lengths; and the collecting lens portion is disposed in the path of the laser light and is further irradiated than the optical path length difference generating portion On the surface side, the irradiation region of the light from the plurality of light transmitting portions is superposed on the irradiation surface; and the divided lens portion and the optical path length difference generating portion are It is arranged close to, and in the arrangement direction of the plurality of light transmitting portions, from said plurality of light transmitting portions of each of the light exit surface of the exit-width coefficient is smaller than the pitch of the plurality of light-transmitting portion. A light-emitting device according to any one of claims 1 to 6, wherein the spatial light modulator is disposed on the irradiation surface of the light irradiation device; the projection optical system Transmitting the spatially modulated light to the object by the spatial light modulator; and moving the mechanism to move the spatially modulated light on the object at the illumination position; and The control unit controls the spatial light modulator in synchronization with the movement of the irradiation position by the moving mechanism.