Optical element holding unit and drawing device

Abstract

A holding unit (72) for holding an optical element comprises a first member (75), a second member (76), a displacement mechanism (73), and a suction mechanism (77). A microlens array (71), which is an optical element, is fixed to the first member (75). The second member (76) is in surface contact with the first member (75) and supports the first member (75). The displacement mechanism (73) displaces the first member (75) relative to the second member (76) and adjusts the relative position of the first member (75) with respect to the second member (76). The suction mechanism (77) sucks in the atmosphere at the part of contact between the first member (75) and the second member (76), thereby using suction to fix the first member (75), of which the relative position with respect to the second member (76) is adjusted, to the second member (76). The microlens array (71) can thereby be held with high positional accuracy.

Description

Optical element holding unit and imaging device

[0001] The present invention relates to an optical element holding unit that holds an optical element, and an imaging device that includes the optical element holding unit. [Reference to Related Applications] This application claims the benefit of priority from Japanese Patent Application JP2023-149939, filed on September 15, 2023, the entire disclosure of which is incorporated herein by reference.

[0002] Conventionally, when drawing a pattern on a printed circuit board, a semiconductor substrate, or the like (hereinafter referred to as a "substrate"), a drawing device is used that directly draws a pattern by irradiating a photosensitive material formed on the substrate with modulated light and scanning the light irradiation area. In the drawing head of such a drawing device, it is necessary to hold multiple optical elements that guide light from a light source to the substrate at predetermined positions with high positional accuracy. Furthermore, holding optical elements with high positional accuracy is also required in devices other than the drawing device.

[0003] For example, Japanese Patent Laid-Open Publication No. 11-102525 (Document 1) proposes a lens position adjusting / fixing device for fixing a lens in an optical information recording / reproducing device. In the lens position adjusting / fixing device 27 shown in FIGS. 1 and 2 , a lens frame 10 placed on an L-shaped base 12 is held by being biased against the base 12 by a leaf spring retainer 28. When adjusting the position of the lens frame 10 in the optical axis direction, an adjustment jig 20 is inserted into a through-hole 29 in the base 12, and a portion of the retainer 28 is lifted and separated from the lens frame 10, thereby reducing the biasing force of the retainer 28. In this state, the adjustment jig 20 is rotated, and an eccentric pin 20a provided on the adjustment jig 20 pushes and displaces the lens frame 10 in the optical axis direction. Thereafter, when the adjustment jig 20 is pulled out of the through-hole 29, the retainer 28 returns to its original shape by its restoring force, thereby biasing and holding the lens frame 10 against the base 12.

[0004] Furthermore, Japanese Patent Laid-Open Publication No. 2004-151681 (Document 2) proposes a technique for adjusting and fixing the position of an anamorphic prism that shapes a beam emitted from a semiconductor laser. As shown in Figures 1 and 2, anamorphic prisms 11 and 12 are placed on a flat mounting plate 13 and aligned with the beam emitted from a semiconductor laser 20 using an adjustment jig. A photocurable adhesive is applied to the mounting plate 13 at the positions where the anamorphic prisms 11 and 12 will be placed. The adhesive is cured by the laser light emitted from the semiconductor laser 20, bonding the anamorphic prisms 11 and 12 to the mounting plate 13.

[0005] Japanese Patent Laid-Open Publication No. 2010-237385 (Document 3) proposes an optical component holding unit for holding an optical component such as a mirror used in an optical device such as a fiber laser. In the optical component holding unit 1 shown in FIG. 1 , an opening A of an air intake hole 11c is provided on the upper surface 11a of the optical component holding member 11. When the optical component 10 is placed on the surface 11a of the optical component holding member 11, the air in the air intake hole 11c is sucked in by the exhaust unit, and the optical component 10 is adsorbed to the optical component holding member 11. Then, adhesive 12 is applied to the outer periphery of the optical component 10, and when the adhesive 12 hardens, the exhaust by the exhaust unit (i.e., the suction of the optical component 10) is stopped. This completes the fixation of the optical component 10.

[0006] Incidentally, in the lens position adjusting and fixing device 27 of Document 1, when the retainer 28 returns to its original shape due to a restoring force, the retainer 28 may collide with the lens frame 10, causing the lens frame 10 to become misaligned. Furthermore, in the technology of Document 2, the surface tension of the adhesive and unpredictable behavior that occurs when the adhesive hardens (e.g., uneven contraction of the adhesive) may cause the anamorphic prisms 11, 12 to become misaligned. In the optical holding unit 1 of Document 3, when the temperature of the device in which the optical holding unit 1 is installed fluctuates, the optical component 10 fixed by the adhesive 12 may become displaced from its fixed position due to the difference in thermal expansion coefficient between the adhesive 12 and the optical holding member 11.

[0007] An object of the present invention is to hold an optical element with high positional accuracy.

[0008] Aspect 1 of the present invention is an optical element holding unit for holding an optical element, comprising: a first member to which the optical element is fixed; a second member that is in face-to-face contact with the first member and supports the first member; a displacement mechanism that displaces the first member relative to the second member and adjusts the relative position of the first member relative to the second member; and a suction mechanism that sucks in the atmosphere at the contact point between the first member and the second member, thereby adsorbing and fixing the first member, whose relative position relative to the second member has been adjusted, to the second member.

[0009] According to the present invention, the optical element can be held with high positional accuracy.

[0010] Aspect 2 of the present invention is an optical element holding unit of aspect 1, in which a recess is provided on only one of the first contact surface of the first member that contacts the second member and the second contact surface of the second member that contacts the first member.

[0011] Aspect 3 of the present invention is the optical element holding unit of Aspect 1 (which may be Aspect 1 or 2), in which the relative movement of the first member by the displacement mechanism is a rotational movement around a predetermined central axis.

[0012] A fourth aspect of the present invention is the optical element holding unit of the third aspect, wherein the first member is annular and has the central axis as its center.

[0013] Aspect 5 of the present invention is an optical element holding unit of aspect 4, wherein an annular groove portion centered on the central axis is provided on only one of the first contact surface of the first member that contacts the second member and the second contact surface of the second member that contacts the first member.

[0014] A sixth aspect of the present invention is the optical element holding unit of the first aspect (which may be any one of the first to fifth aspects), in which the displacement mechanism is a manual mechanism.

[0015] Aspect 7 of the present invention is an optical element holding unit of Aspect 1 (which may be any one of Aspects 1 to 6), in which, when the first member is relatively displaced by the displacement mechanism, the suction mechanism sucks the atmosphere at the contact point between the first member and the second member, so that the first member is adsorbed to the second member in a manner that allows for relative displacement with a suction force that is smaller than when the first member is fixed to the second member.

[0016] Aspect 8 of the present invention is an optical element holding unit of aspect 1 (which may be any one of aspects 1 to 6), in which, when the first member is relatively displaced by the displacement mechanism, atmosphere is ejected at the contact point between the first member and the second member.

[0017] A ninth aspect of the present invention is a drawing apparatus that draws a pattern by irradiating a substrate with light, the drawing apparatus comprising: a stage that holds the substrate; a drawing head that irradiates an upper surface of the substrate with modulated light; and a scanning mechanism that moves the stage relative to the drawing head in a scanning direction parallel to the upper surface of the substrate. The drawing head comprises a plurality of optical elements, and an optical element holding unit according to any one of aspects 1 to 8 that holds one of the plurality of optical elements.

[0018] The above and other objects, features, aspects and advantages will become more apparent from the following detailed description of the invention which proceeds with reference to the accompanying drawings.

[0019] It is a perspective view showing a drawing device according to one embodiment. It is a diagram showing the configuration of a first drawing head. It is a plan view of a microlens array part. It is a side view of the microlens array part. It is a cross-sectional view of a holding unit. It is a perspective view of a first member. It is a diagram showing the flow of position adjustment of the first member.

[0020] FIG. 1 is a perspective view showing a drawing apparatus 1 according to one embodiment of the present invention. The drawing apparatus 1 is a direct drawing apparatus that draws a pattern by irradiating a photosensitive material on a substrate 9 with spatially modulated, approximately beam-like light and scanning the light irradiation area over the substrate 9. In FIG. 1, three mutually orthogonal directions are indicated by arrows as the X direction, the Y direction, and the Z direction. In the example shown in FIG. 1, the X direction and the Y direction are horizontal directions that are perpendicular to each other, and the Z direction is a vertical direction (i.e., an up-down direction). The same applies to other figures.

[0021] The substrate 9 is, for example, a printed circuit board having a substantially rectangular flat plate shape. On the (+Z) side main surface (hereinafter also referred to as the "top surface 91") of the substrate 9, a resist film formed of a photosensitive material is provided on a copper layer. In the drawing device 1, a circuit pattern is drawn (i.e., formed) on the resist film of the substrate 9. Note that the type and shape of the substrate 9 may be variously changed.

[0022] The imaging device 1 includes a stage 21 , a stage moving mechanism 22 , an alignment unit 3 , an imaging unit 4 , a first head support unit 61 , and a second head support unit 62 .

[0023] The stage 21 is a substantially rectangular, flat member that is located below the alignment unit 3 and the imaging unit 4 (i.e., on the (-Z) side). The stage 21 includes a substrate holding unit 25 that holds the horizontal substrate 9 from below. The substrate holding unit 25 is, for example, a vacuum chuck that holds the lower surface of the substrate 9 by suction. The substrate holding unit 25 may have a structure other than a vacuum chuck, and may be, for example, a mechanical chuck. The upper surface 91 of the substrate 9 placed on the substrate holding unit 25 is substantially perpendicular to the Z direction and substantially parallel to the X and Y directions.

[0024] The stage moving mechanism 22 is a moving mechanism that moves the stage 21 relatively in the horizontal direction (i.e., in a direction approximately parallel to the upper surface 91 of the substrate 9) with respect to the alignment unit 3 and the imaging unit 4. The stage moving mechanism 22 is attached to the upper surface of the base 11 and is supported from below by the base 11. The base 11 is, for example, a substantially rectangular parallelepiped member whose length in the Y direction is longer than its length in the X direction.

[0025] The stage movement mechanism 22 includes a first movement mechanism 23 and a second movement mechanism 24. The second movement mechanism 24 supports the stage 21 from below and linearly moves the stage 21 in the X direction along a guide rail. The first movement mechanism 23 supports the second movement mechanism 24 from below and linearly moves the stage 21 together with the second movement mechanism 24 in the Y direction along the guide rail. The drive sources for the first movement mechanism 23 and the second movement mechanism 24 are, for example, linear servo motors or motors attached to ball screws. The structures of the first movement mechanism 23 and the second movement mechanism 24 may be modified in various ways.

[0026] The drawing apparatus 1 may be provided with a stage rotation mechanism that rotates the stage 21 around a rotation axis extending in the Z direction. The drawing apparatus 1 may also be provided with a stage lifting mechanism that moves the stage 21 in the Z direction. For example, a servo motor can be used as the stage rotation mechanism. For example, a linear servo motor can be used as the stage lifting mechanism. The structures of the stage rotation mechanism and the stage lifting mechanism may be modified in various ways.

[0027] The first head support unit 61 and the second head support unit 62 are erected on the upper surface of the base 11. In the example shown in Fig. 1, the first head support unit 61 and the second head support unit 62 are each gate-shaped members (so-called gantries) that straddle the stage 21 and the stage movement mechanism 22. The first head support unit 61 and the second head support unit 62 have approximately the same shape and are arranged side by side in the Y direction. The first head support unit 61 is fixed to the base 11 and does not move in the horizontal or vertical directions.

[0028] The second head support unit 62 is disposed on the (+Y) side of the first head support unit 61. The lower end of the second head support unit 62 on the (+X) side and the lower end of the (-X) side are attached to a pair of guides 63 located on the (+X) side and the (-X) side of the stage movement mechanism 22. Each guide 63 is, for example, an LM guide extending substantially linearly and substantially parallel to the Y direction, and supports the second head support unit 62 in a state where it can move in the Y direction. The second head support unit 62 is movable in the Y direction on the (+Y) side of the first head support unit 61 on the base 11. The second head support unit 62 is disposed in the position shown in FIG. 1 when drawing is performed on the substrate 9 in the drawing apparatus 1, and is moved to the (+Y) side as necessary during maintenance, etc. The second head support unit 62 moves in the Y direction by, for example, an operator manually pushing the second head support unit 62. Note that the second head support unit 62 does not move in the X direction or in the vertical direction.

[0029] As shown in FIG. 1, the alignment unit 3 includes multiple alignment cameras 31 (three in the example shown in FIG. 1) arranged in the X direction. Each alignment camera 31 is a digital camera having, for example, a CCD (Charged Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) as an imaging element. Each alignment camera 31 is supported by a first head support unit 61 above the stage 21 and the stage movement mechanism 22. In the example shown in FIG. 1, the three alignment cameras 31 are attached to the (-Y) side of the first head support unit 61. The number of alignment cameras 31 in the alignment unit 3 may be one or two, or may be four or more.

[0030] Each alignment camera 31 is an imaging unit that captures an image of an alignment mark (not shown) that is provided in advance on an upper surface 91 of the substrate 9. In the drawing device 1, the position of the substrate 9 on the stage 21 is detected based on the captured image (i.e., the image of the alignment mark) acquired by the alignment camera 31. Then, based on the detected position of the substrate 9, alignment of the substrate 9 (i.e., correction of the relative position of the substrate 9 with respect to the first drawing head group 401 and the second drawing head group 402, which will be described later) is performed.

[0031] The drawing unit 4 includes a first drawing head group 401 supported by a first head support part 61 and a second drawing head group 402 supported by a second head support part 62. The first drawing head group 401 and the second drawing head group 402 each include a plurality of drawing heads 41. Each drawing head 41 irradiates the upper surface 91 of the substrate 9 with modulated light.

[0032] In the example shown in FIG. 1 , the first drawing head group 401 includes four drawing heads 41 arranged in a substantially straight line substantially parallel to the X direction. The four drawing heads 41 are positioned substantially identically in the Y and Z directions. The four drawing heads 41 have substantially the same shape and structure. The second drawing head group 402 also includes four drawing heads 41 arranged in a substantially straight line substantially parallel to the X direction. The four drawing heads 41 are positioned substantially identically in the Y and Z directions. The four drawing heads 41 have substantially the same shape and structure. The drawing heads 41 of the first drawing head group 401 and the drawing heads 41 of the second drawing head group 402 also have substantially the same shape and structure. Note that the number and arrangement of the drawing heads 41 included in the first drawing head group 401 and the number and arrangement of the drawing heads 41 included in the second drawing head group 402 may be changed in various ways.

[0033] The four drawing heads 41 of the first drawing head group 401 are attached to a portion on the (+Y) side of the first head support part 61 and are supported by the first head support part 61 above the stage 21 and the stage movement mechanism 22. That is, the first drawing head group 401 is disposed on a side of the first head support part 61 that faces the second head support part 62 in the Y direction. The four drawing heads 41 of the second drawing head group 402 are attached to a portion on the (-Y) side of the second head support part 62 and are supported by the second head support part 62 above the stage 21 and the stage movement mechanism 22. That is, the second drawing head group 402 is disposed on a side of the second head support part 62 that faces the first head support part 61 in the Y direction. In the state shown in Figure 1, the second drawing head group 402 is adjacent to the first drawing head group 401 in the Y direction on the (+Y) side of the first drawing head group 401 (i.e., arranged in close proximity or contact), and faces the first drawing head group 401 in the Y direction.

[0034] The four drawing heads 41 of the first drawing head group 401 are arranged at approximately equal pitches in the X direction. The four drawing heads 41 of the second drawing head group 402 are also arranged at approximately equal pitches in the X direction. The pitch in the X direction of the four drawing heads 41 of the first drawing head group 401 and the pitch in the X direction of the four drawing heads 41 of the second drawing head group 402 are approximately the same. In the following description, the pitch in the X direction of the drawing heads 41 of the first drawing head group 401 and the pitch in the X direction of the drawing heads 41 of the second drawing head group 402 are also referred to as "drawing head pitch."

[0035] The four drawing heads 41 of the second drawing head group 402 are arranged at positions different in the X direction from the four drawing heads 41 of the first drawing head group 401. As a result, the second drawing head group 402 irradiates the upper surface 91 of the substrate 9 with modulated light at a position different in the X direction from that of the first drawing head group 401. Specifically, the four drawing heads 41 of the second drawing head group 402 are arranged at positions shifted toward the (+X) side by a distance of half the drawing head pitch from the four drawing heads 41 of the first drawing head group 401. Therefore, of the four drawing heads 41 of the second drawing head group 402, the three drawing heads 41 on the (−X) side are each positioned approximately at the center in the X direction of the two drawing heads 41 of the first drawing head group 401 that face each other in the Y direction.

[0036] FIG. 2 is an enlarged view of one drawing head 41 of the first drawing head group 401, viewed from the (+Y) side. FIG. 2 also shows a portion of the first head support part 61. The drawing head 41 is attached to the (+Y) side surface of the first head support part 61. The upper part of the drawing head 41 protrudes upward from the upper surface (i.e., the end surface on the (+Z) side) of the first head support part 61. The structure of the other drawing heads 41 shown in FIG. 1 is substantially the same as that shown in FIG. 2. Note that each drawing head 41 of the second drawing head group 402 is arranged in the opposite direction in the Y direction to the drawing head 41 shown in FIG. 2, and is attached to the second head support part 62 (see FIG. 1).

[0037] The drawing head 41 includes a light source unit 412, an illumination optical system 413, a spatial light modulation unit 414, a first projection optical system 415, a microlens array unit 416, a second projection optical system 417, and a drawing head base 418. In the example shown in FIG. 2 , the drawing head base 418 is a substantially flat member that is substantially perpendicular to the Y direction. When viewed along the Y direction, the drawing head base 418 has a substantially rectangular shape that is elongated in the Z direction. The drawing head base 418 is fixed to the (+Y) side surface of the first head support unit 61. The light source unit 412, the illumination optical system 413, the spatial light modulation unit 414, the first projection optical system 415, the microlens array unit 416, and the second projection optical system 417 are fixed to the (+Y) side surface of the drawing head base 418 and are covered from the (+Y) side by a drawing head cover (not shown in FIG. 2 ).

[0038] In the example shown in FIG. 2 , the light source unit 412 is an optical fiber that guides light emitted from a light source (not shown) to the illumination optical system 413. For example, an LD (Laser Diode) or an LED (Light Emitting Diode) can be used as the light source. In this embodiment, a fiber bundle and multiple LDs are used as the optical fiber and light source. Note that the light source may be a light source other than an LD or an LED. The light source unit 412 is disposed below the drawing head 41 and emits light upward.

[0039] An illumination optical system 413 is disposed substantially vertically above the light source unit 412. The illumination optical system 413 has optical elements such as lenses arranged substantially linearly and substantially parallel to the vertical direction. In FIG. 2 , the optical elements of the illumination optical system 413 are surrounded by a two-dot chain line. The illumination optical system 413 guides the light emitted from the light source unit 412 upward. The light that passes through the illumination optical system 413 enters a spatial light modulation unit 414 disposed at the upper end of the drawing head 41 via mirrors 419 a and 419 b.

[0040] The spatial light modulation unit 414 includes a light modulator such as a DMD (Digital Micro Mirror Device) or a GLV (Grating Light Valve) (registered trademark of Silicon Light Machines, Sunnyvale, California). The light modulator modulates (i.e., spatially modulates) the light from the light source guided by the illumination optical system 413 and guides the modulated light downward. Note that the light modulator may be one other than a DMD or a GLV.

[0041] A first projection optical system 415, a microlens array unit 416, and a second projection optical system 417 are arranged substantially vertically below the spatial light modulation unit 414. The first projection optical system 415 guides modulated light from the spatial light modulation unit 414 downward. The first projection optical system 415 has a plurality of optical elements such as lenses arranged substantially linearly and substantially parallel to each other in the vertical direction. In FIG. 2, the plurality of optical elements of the first projection optical system 415 are surrounded by a two-dot chain line. Light that passes through the first projection optical system 415 is incident on the microlens array unit 416.

[0042] The microlens array section 416 includes a microlens array 71 and a holding unit 72. The microlens array 71 condenses and guides the light guided by the first projection optical system 415 to the second projection optical system 417. The holding unit 72 is an optical element holding unit that holds the microlens array 71, which is an optical element. The structure of the holding unit 72 will be described later.

[0043] The second projection optical system 417 guides light from the microlens array unit 416 downward. The second projection optical system 417 has optical elements such as lenses arranged in a substantially linear manner and substantially parallel to the vertical direction. In FIG. 2, the optical elements of the second projection optical system 417 are surrounded by a two-dot chain line. Light passing through the second projection optical system 417 is irradiated onto the upper surface 91 (see FIG. 1) of the substrate 9 located below the drawing head 41. A focus sensor or the like used for focus adjustment of the drawing head 41 may be provided near the lower end of the second projection optical system 417.

[0044] In the light source unit 412 of the drawing head 41, the above-mentioned optical fiber may be omitted, and the light source may be fixed to the (+Y)-side surface of the drawing head base 418. In the drawing head 41, the light source unit 412, the illumination optical system 413, the spatial light modulation unit 414, the first projection optical system 415, the microlens array unit 416, and the second projection optical system 417 may be arranged in this order from the (+Z) side to the (−Z) side on the (+Y)-side surface of the drawing head base 418.

[0045] The pattern drawing on the substrate 9 in the drawing apparatus 1 is performed by a so-called multi-pass method. Specifically, modulated light is irradiated onto the upper surface 91 of the substrate 9 from the plurality of drawing heads 41 supported by the first head support unit 61 and the plurality of drawing heads 41 supported by the second head support unit 62, while the substrate 9 is moved in the Y direction by the first moving mechanism 23 of the stage moving mechanism 22 to pass below the drawing unit 4. As a result, the irradiation area of ​​the light from the plurality of drawing heads 41 is scanned in the Y direction on the substrate 9, and drawing on the substrate 9 is performed.

[0046] Next, the second movement mechanism 24 moves the substrate 9 stepwise by a predetermined distance in the X direction. Then, the first movement mechanism 23 moves the substrate 9 in the Y direction, and light is again irradiated onto the substrate 9 from the multiple drawing heads 41 in parallel with this movement, thereby drawing on the substrate 9. In the drawing device 1, a pattern is drawn on the substrate 9 by alternately irradiating the substrate 9 moving in the Y direction with light and stepping the substrate 9 in the X direction.

[0047] In the following description, the Y direction will also be referred to as the "main scanning direction" or "scanning direction," and the X direction will also be referred to as the "sub-scanning direction" or "width direction." The main scanning direction and the sub-scanning direction are directions that are approximately parallel to the upper surface 91 of the substrate 9. In the stage movement mechanism 22, the first movement mechanism 23 is a main scanning mechanism that moves the stage 21 relatively to the drawing head 41 in the main scanning direction. The second movement mechanism 24 is a sub-scanning mechanism that moves the stage 21 relatively to the drawing head 41 in the sub-scanning direction.

[0048] In the drawing apparatus 1, drawing on the substrate 9 may be performed by a single-pass method (also called a one-pass method), in which drawing of a pattern on the substrate 9 is completed by moving the substrate 9 relative to the drawing head 41 only once in the Y direction. In this case, sub-scanning of the substrate 9 by the second moving mechanism 24 (i.e., step movement in the X direction) is not performed when drawing the pattern. In other words, the stage moving mechanism 22 is a scanning mechanism that moves the stage 21 relative to the drawing head 41 at least in the scanning direction.

[0049] FIG. 3 is a plan view showing the microlens array unit 416. FIG. 4 is a side view of the microlens array unit 416 as viewed from the (-X) side. FIG. 5 is a cross-sectional view of the holding unit 72 of the microlens array unit 416 taken along the line VV in FIG. 3. FIG. 6 is a perspective view of a first member 75, which is part of the holding unit 72, as viewed obliquely from below. In FIGS. 3 and 4, the microlens array 71 is indicated by a thick dashed line to facilitate understanding of the structure of the holding unit 72.

[0050] The holding unit 72 includes a first member 75, a second member 76, a displacement mechanism 73, and a suction mechanism 77. The second member 76 is a substantially flat member that is substantially perpendicular to the Z direction. The second member 76 has a substantially rectangular shape in a plan view, and the width in the X direction at the end of the second member 76 on the (+Y) side is smaller than the width in the X direction at other portions of the second member 76. The first member 75 and the displacement mechanism 73 are disposed on an upper surface 767 of the second member 76 (i.e., the main surface on the (+Z) side). The suction mechanism 77 is attached to a lower surface (i.e., the main surface on the (-Z) side) of the second member 76. The upper surface 767 and the lower surface of the second member 76 are each substantially flat and substantially perpendicular to the Z direction.

[0051] A second through-hole 761 is provided in the approximate center of the second member 76, penetrating the second member 76 in the up-down direction (i.e., the Z direction). The second through-hole 761 is a substantially disk-shaped (or cylindrical) space centered on a central axis J1 extending parallel to the up-down direction. Suction holes 764, to which the suction mechanism 77 is attached, are provided in the second member 76 on the (+X) side and the (+Y) side of the second through-hole 761. The suction hole 764 is a through-hole that penetrates the second member 76 in the up-down direction. The suction hole 764 is smaller than the second through-hole 761 in a plan view. The suction hole 764 is spaced apart from the second through-hole 761 in the X direction and the Y direction. In the example shown in FIG. 3 , the second through-hole 761 and the suction hole 764 each have a substantially circular shape in a plan view, but the shapes are not limited to being substantially circular and may be variously modified.

[0052] Two movement limiting portions 762 are provided on an upper surface 767 of the second member 76, protruding from the upper surface 767 toward the (+Z) side. The movement limiting portions 762 are generally columnar portions standing on the upper surface 767 of the second member 76. The movement limiting portions 762 are disposed at a distance from the second through-hole 761 on the (-Y) side. In the example shown in FIGS. 3 and 4 , each movement limiting portion 762 is a generally cylindrical portion extending generally parallel to the Z direction. The movement limiting portions 762 contact the outer surface of the first member 75, thereby limiting the movement of the first member 75 in the horizontal direction.

[0053] The first member 75 is an annular member centered on the central axis J1. In the example shown in FIGS. 3 to 6 , the first member 75 is a substantially annular plate-shaped (or substantially cylindrical) member centered on the central axis J1. A first through-hole 751 penetrating the first member 75 in the up-down direction is provided in the center of the first member 75. The first through-hole 751 is composed of an upper space 752 and a lower space 753. The upper space 752 is a portion of the first through-hole 751 on the (+Z) side (i.e., above the first through-hole 751) and is a substantially rectangular plate-shaped (or substantially rectangular parallelepiped) space centered on the central axis J1. The lower space 753 is a portion of the first through-hole 751 on the (-Z) side (i.e., below the first through-hole 751) and is a substantially circular plate-shaped (or substantially cylindrical) space centered on the central axis J1. The lower space 753 is continuous with the (-Z) side of the upper space 752. The shape of the lower space 753 in a plan view is substantially the same as the shape of the second through hole 761 of the second member 76 in a plan view. In other words, the shapes of the lower space 753 and the second through hole 761 in a plan view are substantially circular and have substantially the same diameter.

[0054] A microlens array 71 is fixed to the first member 75. In the example shown in FIGS. 3 and 4 , the microlens array 71, which is substantially rectangular in plan view, is disposed above the first member 75 and fixed to the upper surface (i.e., the surface on the (+Z) side) of the first member 75. The peripheral edge of the lower surface (i.e., the surface on the (-Z) side) of the microlens array 71 contacts the periphery of the first through-hole 751 on the upper surface of the first member 75. In the microlens array 71, a substantially rectangular plate-shaped portion (hereinafter also referred to as the "lower array portion") 711 excluding the peripheral edge of the lower surface protrudes downward from the peripheral portion and is inserted into the first through-hole 751 from above. The lower array portion 711 of the microlens array 71 is disposed in an upper space 752 of the first through-hole 751.

[0055] The first member 75 is placed on the upper surface 767 of the second member 76 so that the lower space 753 of the first through hole 751 overlaps with the second through hole 761 of the second member 76 in a plan view. In other words, the lower opening of the first through hole 751 of the first member 75 and the upper opening of the second through hole 761 of the second member 76 substantially overlap with each other in a plan view.

[0056] A lower surface (i.e., the surface on the (-Z) side) 756 of the first member 75 is a substantially annular plane that is substantially perpendicular to the Z direction. The lower surface 756 of the first member 75 is in surface contact with an upper surface 767 of the second member 76 around the second through-hole 761 of the second member 76. As a result, the first member 75 is supported from the (-Z) side by the second member 76. The upper surface 767 of the second member 76 is in surface contact with the lower surface 756 of the first member 75 around the first through-hole 751 of the first member 75. The lower surface 756 of the first member 75 is a first contact surface that is in surface contact with the second member 76, and the upper surface 767 of the second member 76 is a second contact surface that is in surface contact with the first member 75.

[0057] A groove 754 recessed from the lower surface 756 toward the (+Z) side is provided on the lower surface 756 of the first member 75. The groove 754 is a substantially annular recess centered on the central axis J1. In the example shown in FIG. 4 , the depth of the groove 754 (i.e., the height in the Z direction from the lower surface 756 of the first member 75 to the canopy portion of the groove 754) is smaller than the height in the Z direction of the lower space 753 of the first through-hole 751. In the example shown in FIGS. 3 and 5 , a portion of the groove 754 on the (+X) side and the (+Y) side of the central axis J1 overlaps with the suction hole 764 of the second member 76 in a plan view, and the groove 754 and the suction hole 764 are in communication with each other.

[0058] A displacement mechanism 73 is disposed on the upper surface 767 of the second member 76 on the (+Y) side of the first member 75. The displacement mechanism 73 includes a micrometer head 731, a support 732, and a displacement unit 733. The support 732 is, for example, a substantially rectangular parallelepiped member and is fixed to the upper surface 767 of the second member 76 on the (+Y) side of the first member 75. A substantially cylindrical protrusion 734 that protrudes in the (-Y) direction is provided on the (-Y) side end face of the support 732. The tip of the protrusion 734 on the (-Y) side contacts the outer surface of the first member 75. The protrusion 734 of the support 732 and the two movement limiting units 762 contact the outer surface of the first member 75 from the outside in the radial direction (hereinafter simply referred to as the "radial direction") centered on the central axis J1, thereby preventing movement of the first member 75 in the X and Y directions.

[0059] The micrometer head 731 is a substantially cylindrical member extending substantially parallel to the X direction. The micrometer head 731 is attached to a portion on the (-X) side of the support portion 732. The micrometer head 731 is supported by the support portion 732 so as to be rotatable about a rotation axis extending in the X direction. The micrometer head 731 is rotated, for example, manually by an operator. Specifically, the operator holds the (-X) side end (i.e., the operating portion) of the micrometer head 731 with their fingers and rotates it manually, thereby rotating the (+X) side end (i.e., the spindle) of the micrometer head 731.

[0060] The displacement portion 733 is, for example, a substantially flat plate-shaped member that is substantially perpendicular to the Z direction and is disposed on the (+X) side of the micrometer head 731. A portion of the displacement portion 733 on the (+Y) side is attached to the micrometer head 731. A portion of the displacement portion 733 on the (-Y) side overlaps the first member 75 in a plan view and is in surface contact with the upper surface of the first member 75 (i.e., the (+Z) side surface). As described above, when an operator pinches the (-X) side end of the micrometer head 731 and rotates it, the displacement portion 733 moves in the X direction in accordance with the displacement of the (+X) side end of the micrometer head 731 in the X direction. As a result, the first member 75, which is in surface contact with the displacement portion 733, rotates substantially horizontally (i.e., substantially parallel to the XY plane) about the central axis J1.

[0061] That is, the displacement mechanism 73 is a manual mechanism that rotates the first member 75 relative to the second member 76 (i.e., relatively displaces the first member 75) in the circumferential direction about the central axis J1 (hereinafter simply referred to as the "circumferential direction"), thereby adjusting the relative position of the first member 75 in the circumferential direction with respect to the second member 76. Note that the manual mechanism refers to a mechanism in which an operator or the like directly applies force from their fingers or the like to the mechanism, causing the mechanism to operate using that force as a drive source. In the holding unit 72, the first member 75, the second member 76, and the displacement mechanism 73 form a so-called grinding-type rotation stage.

[0062] In the microlens array unit 416, light that has passed through the microlens array 71 is guided downward (i.e., in the (-Z) direction) through the first through-hole 751 of the first member 75 and the second through-hole 761 of the second member 76, and is incident on the second projection optical system 417 (see FIG. 2). As described above, when the relative position of the first member 75 in the circumferential direction with respect to the second member 76 is adjusted by the displacement mechanism 73, the incident position in the second projection optical system 417 of the light that has passed through the microlens array 71 is changed, and the irradiation position of the light that passes through the second projection optical system 417 and is irradiated onto the upper surface 91 of the substrate 9 is also adjusted.

[0063] The suction mechanism 77 includes a nozzle 771 and a pipe 772. The nozzle 771 is inserted into the suction hole 764 of the second member 76 from the (-Z) side and attached to the second member 76. The pipe 772 connects the nozzle 771 to a pump (not shown). When the pump is driven, gas inside the suction hole 764 is sucked through the nozzle 771, and gas inside the groove portion 754 of the first member 75 that communicates with the suction hole 764 is also sucked. A small amount of gas present between the lower surface 756 of the first member 75 and the upper surface 767 of the second member 76 is also sucked. That is, the suction mechanism 77 sucks the atmosphere at the contact portion between the first member 75 and the second member 76 (i.e., the portion where the first member 75 and the second member 76 are in surface contact). As a result, the first member 75 is sucked and fixed to the upper surface 767 of the second member 76. The atmosphere is the same as the gas (for example, the atmosphere) that fills the interior of a clean room or the like in which the imaging apparatus 1 is placed.

[0064] When the first member 75 is fixed to the second member 76 by the suction of the suction mechanism 77, the first member 75 cannot rotate in the circumferential direction about the central axis J1 and cannot move in the up-down direction. Furthermore, the first member 75 cannot move in the X-direction and the Y-direction due to the movement limiting portion 762 and the protruding portion 734, regardless of whether or not suction by the suction mechanism 77 is applied.

[0065] In the imaging device 1, when the relative position of the first member 75 with respect to the second member 76 in the circumferential direction (i.e., the orientation of the first member 75 in the circumferential direction) is adjusted, the pump is first stopped, and suction by the suction mechanism 77 is stopped. This releases the first member 75 from the suction fixation to the second member 76, making the first member 75 rotatable about the central axis J1 ( FIG. 7 : step S11). Next, an operator or the like manually rotates the micrometer head 731 of the displacement mechanism 73, thereby rotating the first member 75 in the circumferential direction and precisely adjusting the position of the first member 75 in the circumferential direction (i.e., the orientation of the first member 75) (step S12). When the first member 75 is positioned at a desired position in the circumferential direction, the pump is driven, and the suction mechanism 77 suctions the atmosphere at the contact portion between the first member 75 and the second member 76. As a result, the first member 75 is fixed by suction to the second member 76, and the first member 75 is immovable in a state where it is positioned with high positional accuracy relative to the second member 76 (step S13).

[0066] In the imaging device 1, the suction state by the suction mechanism 77 is maintained even while imaging is being performed on the substrate 9, so that the first member 75 is maintained in a state of being fixed with high positional accuracy relative to the second member 76. As a result, imaging on the substrate 9 is achieved with high accuracy.

[0067] In the holding unit 72, while suction by the suction mechanism 77 continues (i.e., while the first member 75 is fixed to the second member 76), the fixation of the first member 75 to the second member 76 may be reinforced by an additional fixing means. The additional fixing means may be a mechanical fixing means such as screw fastening, or may be fixing by adhesive, etc. When the mechanical fixing means is screw fastening, for example, the first member 75 is screwed to the second member 76 by screws threaded into a plurality of screw holes 755 provided in the first member 75.

[0068] In the holding unit 72, even if a force is applied to the first member 75 from the additional fixing means when the additional fixing means is applied, the first member 75 will not be displaced because the first member 75 is fixed to the second member 76 by suction using the suction mechanism 77. For example, even if a circumferential force is applied to the first member 75 when the screws are fastened, the relative position of the first member 75 to the second member 76 is maintained.

[0069] When adjusting the circumferential position of the first member 75, suction by the suction mechanism 77 does not necessarily have to be stopped. For example, in the above-described step S11, the suction mechanism 77 may suck the atmosphere at the contact portion between the first member 75 and the second member 76 with a suction force that is weaker than that when the first member 75 is fixed to the second member 76. In this case, the circumferential position of the first member 75 is adjusted by the displacement mechanism 73 in step S12 while the first member 75 is attracted with a relatively weak suction force in a state in which it can move relative to the second member 76. This makes it possible to adjust the circumferential position of the first member 75 while preventing the first member 75 from being unintentionally displaced significantly by a slight force.

[0070] Alternatively, in step S11, gas may be supplied from the pump of the suction mechanism 77 to the nozzle 771, and the gas may be ejected from the nozzle 771 into the suction hole 764. This causes the gas to be supplied between the lower surface 756 of the first member 75 and the upper surface 767 of the second member 76. In other words, the suction mechanism 77 ejects the atmosphere at the contact portion between the first member 75 and the second member 76. In this state, in step S12, the displacement mechanism 73 adjusts the circumferential position of the first member 75, thereby reducing the circumferential friction force acting between the first member 75 and the second member 76. As a result, the force required to adjust the circumferential position of the first member 75 can be reduced.

[0071] In the above example, the groove 754 is provided on the lower surface 756 (i.e., the first contact surface) of the first member 75, and the upper surface 767 (i.e., the second contact surface) of the second member 76 does not have any recesses like the groove 754, except for the suction holes 764. However, in the holding unit 72, the groove 754 does not necessarily have to be provided on the first member 75, and the structures of the lower surface 756 of the first member 75 and the upper surface 767 of the second member 76 may be modified in various ways.

[0072] For example, a substantially annular groove centered on the central axis J1 may be provided in the upper surface 767 of the second member 76, and the groove may be in communication with the suction hole 764. In this case, the lower surface 756 of the first member 75 may be substantially free of any recess, or may be provided with a recess that partially or entirely overlaps in plan view with the groove provided in the upper surface 767 of the second member 76. Note that, from the viewpoint of preventing gaps or the like from occurring at the contact portion between the first member 75 and the second member 76 and stably adsorbing the first member 75 to the second member 76, it is preferable that a recess other than the suction hole 764 be provided in only one of the lower surface 756 of the first member 75 and the upper surface 767 of the second member 76, and that the recess be in communication with the suction hole 764.

[0073] As described above, the optical element holding unit (i.e., holding unit 72) that holds an optical element includes a first member 75, a second member 76, a displacement mechanism 73, and a suction mechanism 77. An optical element (in the above example, the microlens array 71) is fixed to the first member 75. The second member 76 supports the first member 75 by being in surface contact with the first member 75. The displacement mechanism 73 displaces the first member 75 relative to the second member 76, adjusting the relative position of the first member 75 with respect to the second member 76. The suction mechanism 77 sucks the atmosphere at the contact portion between the first member 75 and the second member 76, thereby adsorbing and fixing the first member 75, whose relative position with respect to the second member 76 has been adjusted, to the second member 76. This allows the optical element to be held with high positional accuracy, as described above.

[0074] As described above, preferably, a recess (groove 754 in the above example) is provided on only one of the first contact surface of the first member 75 that contacts the second member 76 (lower surface 756 of the first member 75 in the above example) and the second contact surface of the second member 76 that contacts the first member 75 (upper surface 767 of the second member 76 in the above example). By providing this recess, it is possible to increase the adhesive force of the first member 75 to the second member 76. Furthermore, by providing this recess on only one of the first contact surface and the second contact surface, as described above, it is possible to prevent gaps and the like from occurring at the contact portion between the first member 75 and the second member 76, and to stably adhesively attach the first member 75 to the second member 76.

[0075] As described above, the relative movement of the first member 75 by the displacement mechanism 73 is preferably a rotational movement around a predetermined central axis J1. This makes it possible to easily adjust the orientation of the optical element fixed to the first member 75. As in the above example, when the optical element is a microlens array 71, the angle formed between the arrangement direction of the multiple microlenses of the microlens array 71 and the scanning direction of the substrate 9 can be adjusted by adjusting the orientation of the microlens array 71. As a result, the drawing resolution of the drawing device 1 can be easily adjusted.

[0076] As described above, it is more preferable that the first member 75 be annular about the central axis J1. This allows the first member 75 to be in contact with the optical element fixed to the first member 75 over substantially the entire circumference in the circumferential direction about the central axis J1. As a result, the stability of the support of the optical element by the first member 75 can be improved, and the holding unit 72 can hold the optical element with even greater positional accuracy.

[0077] As described above, it is preferable to provide an annular groove (groove 754 in the above example) centered on the central axis J1 on only one of the first contact surface of the first member 75 that contacts the second member 76 and the second contact surface of the second member 76 that contacts the first member 75. By providing this groove, the adhesive force of the first member 75 to the second member 76 can be increased. Furthermore, because the groove is annular, the adhesive force of the first member 75 to the second member 76 can be made substantially uniform in the circumferential direction. As a result, the first member 75 can be stably attached to the second member 76. Furthermore, by providing this groove on only one of the first contact surface and the second contact surface, it is possible to prevent gaps or the like from occurring at the contact portion between the first member 75 and the second member 76, thereby more stably attaching the first member 75 to the second member 76.

[0078] As described above, it is preferable that the displacement mechanism 73 is a manual mechanism, which can reduce the manufacturing cost of the holding unit 72 compared to when the displacement mechanism 73 is mechanically driven (for example, driven by an electric motor).

[0079] As described above, when the displacement mechanism 73 relatively displaces the first member 75, the suction mechanism 77 preferably sucks the atmosphere at the contact portion between the first member 75 and the second member 76, thereby adhering the first member 75 to the second member 76 so as to be relatively displaceable with a suction force smaller than that when the first member 75 is fixed to the second member 76. This makes it possible to prevent the first member 75 from being unintentionally displaced significantly when adjusting the relative position of the first member 75 with respect to the second member 76. As a result, the first member 75 can be held in position with high accuracy. Furthermore, even when the first member 75 is not configured to be placed above the second member 76 (for example, when the first member 75 is disposed below the second member 76), the position of the first member 75 can be easily adjusted.

[0080] As described above, it is also preferable that atmosphere be ejected at the contact portion between the first member 75 and the second member 76 when the displacement mechanism 73 relatively displaces the first member 75. This reduces the force required for the relative movement of the first member 75 with respect to the second member 76, making it easier to adjust the position of the first member 75. As a result, the first member 75 can be held in its position with high precision.

[0081] The above-described drawing apparatus 1, which draws a pattern by irradiating light onto a substrate 9, includes a stage 21, a drawing head 41, and a scanning mechanism (stage moving mechanism 22 in the above example). The stage 21 holds the substrate 9. The drawing head 41 irradiates an upper surface 91 of the substrate 9 with modulated light. The scanning mechanism moves the stage 21 relative to the drawing head 41 in a scanning direction parallel to the upper surface 91 of the substrate 9. The drawing head 41 includes a plurality of optical elements and the above-described optical element holding unit (i.e., holding unit 72). The holding unit 72 holds one optical element (microlens array 71 in the above example) among the plurality of optical elements. As described above, the holding unit 72 can hold the optical elements with high positional accuracy, thereby improving the drawing accuracy of the drawing apparatus 1.

[0082] The holding unit 72 and the imaging device 1 described above can be modified in various ways.

[0083] For example, the optical element fixed to the first member 75 in the holding unit 72 is not limited to the microlens array 71 and may be variously modified. For example, the optical element may be a light modulator (e.g., a DMD) of the spatial light modulation section 414. By adjusting the orientation of the light modulator in the holding unit 72, the drawing resolution of the drawing device 1 can be easily adjusted, in substantially the same way as in the case of the microlens array 71.

[0084] In the holding unit 72, the structure and arrangement of the displacement mechanism 73 may be modified in various ways. For example, the drive unit that is manually driven by the operator in the displacement mechanism 73 is not necessarily limited to the micrometer head 731, and may have another structure. Furthermore, the displacement mechanism 73 may be a mechanically driven mechanism that uses an electric motor or the like as a drive source.

[0085] In the holding unit 72, the relative movement of the first member 75 by the displacement mechanism 73 (i.e., adjustment of the relative position of the first member 75 with respect to the second member 76) does not necessarily have to be the rotational movement described above, and may be modified in various ways. For example, the displacement mechanism 73 may cause the first member 75 to move linearly relative to the second member 76.

[0086] The optical element held by the holding unit 72 does not necessarily have to be disposed on the upper surface of the first member 75 , but may be fixed to another portion of the first member 75 .

[0087] In the holding unit 72, the first member 75 does not necessarily have to be annular, and may have various shapes. Also, the second member 76 does not necessarily have to be provided with the second through-hole 761.

[0088] In the first member 75, a surface other than the lower surface 756 may be the first contact surface that comes into surface contact with the second member 76. Similarly, in the second member 76, a surface other than the upper surface 767 may be the second contact surface that comes into surface contact with the first member 75.

[0089] For example, the optical element held by the holding unit 72 may be the mirror 419a shown in FIG. 2. In this case, for example, the first member 75 is disposed on the (+Z) side of the mirror 419a and holds the mirror 419a from the (+Z) side, and the second member 76 is disposed on the (+Z) side of the first member 75 and supports the first member 75 from the (+Z) side. The first contact surface of the first member 75 is the (+Z) side surface of the first member 75 (i.e., the upper surface), and the second contact surface of the second member 76 is the (-Z) side surface of the second member 76 (i.e., the lower surface). In this case, the first member 75 and the second member 76 may be substantially flat plate-shaped members without through holes.

[0090] The shape of the groove 754 on the lower surface 756 (i.e., the first contact surface) of the first member 75 is not limited to annular and may be modified in various ways. For example, a meandering, curved groove 754 may be provided over substantially the entire surface of the lower surface 756 of the first member 75. Furthermore, the first member 75 may be provided with recesses of various shapes and structures other than the groove 754. For example, a plurality of substantially hemispherical recesses that communicate with each other may be arranged over substantially the entire surface of the lower surface 756 of the first member 75. The same applies when recesses are provided on the upper surface 767 (i.e., the second contact surface) of the second member 76.

[0091] The structure of the drawing head 41 of the drawing device 1 is not limited to the above example and may be modified in various ways. For example, the light source unit 412 may include a light source (e.g., an LED or an LD) arranged on the drawing head base 418. Furthermore, the drawing head 41 may be a drawing head that is substantially L-shaped in side view, and an illumination optical system 413 having a plurality of optical elements arranged linearly in the Y direction may extend substantially horizontally in the Y direction from the spatial light modulation unit 414.

[0092] In the imaging device 1, the stage 21 may be moved in the main scanning direction relative to the first imaging head group 401 and the second imaging head group 402 by the first moving mechanism 23. Therefore, for example, the stage 21 may be fixed, and the first imaging head group 401 and the second imaging head group 402 may be moved in the main scanning direction above the stage 21 by the first moving mechanism 23. Similarly, the first imaging head group 401 and the second imaging head group 402 may be moved in the sub-scanning direction by the second moving mechanism 24.

[0093] The multiple drawing heads 41 do not necessarily need to be supported by the first head support portion 61 and the second head support portion 62, and all of the drawing heads 41 may be supported by a single head support portion. In addition, the number and arrangement of the multiple drawing heads 41 may also be changed as appropriate.

[0094] The substrate 9 on which a pattern is drawn by the drawing apparatus 1 is not necessarily limited to a printed circuit board. The drawing apparatus 1 may draw a pattern on, for example, a semiconductor substrate, a substrate for a semiconductor package, a glass substrate for a flat panel display device such as a liquid crystal display device or a plasma display device, a glass substrate for a photomask, a substrate for a solar cell panel, or the like.

[0095] The holding unit 72 does not necessarily have to be used in the drawing head 41 of the drawing device 1, but may be used to hold an optical element in another configuration of the drawing device 1 or in a device other than the drawing device 1.

[0096] The configurations in the above-described embodiment and each modification may be combined as appropriate as long as they are not mutually contradictory.

[0097] While the invention has been particularly illustrated and described, it should be understood that the foregoing description is illustrative and not restrictive, and that numerous modifications and variations are possible without departing from the scope of the invention.

[0098] REFERENCE SIGNS LIST 1 drawing device 9 substrate 21 stage 22 stage movement mechanism 41 drawing head 71 microlens array 72 holding unit 73 displacement mechanism 75 first member 76 second member 77 suction mechanism 91 upper surface (of substrate) 754 groove 756 lower surface (of first member) 767 upper surface (of second member) J1 central axis

Claims

1. An optical element holding unit for holding an optical element comprising: a first member to which an optical element is fixed; a second member that supports the first member by making surface contact with the first member; a displacement mechanism that displaces the first member relative to the second member and adjusts the relative position of the first member to the second member; and a suction mechanism that adsorbs and fixes the first member, whose relative position to the second member has been adjusted, to the second member by sucking in the atmosphere at the contact portion between the first member and the second member.

2. An optical element holding unit as described in claim 1, wherein a recess is provided on only one of a first contact surface of the first member that contacts the second member and a second contact surface of the second member that contacts the first member.

3. An optical element holding unit as claimed in claim 1, wherein the relative movement of the first member caused by the displacement mechanism is a rotational movement about a predetermined central axis.

4. An optical element holding unit according to claim 3, wherein the first member is annular about the central axis.

5. An optical element holding unit as described in claim 4, wherein an annular groove portion centered on the central axis is provided on only one of a first contact surface of the first member that contacts the second member and a second contact surface of the second member that contacts the first member.

6. An optical element holding unit according to claim 1, wherein the displacement mechanism is a manual mechanism.

7. An optical element holding unit as described in claim 1, wherein when the first member is relatively displaced by the displacement mechanism, the suction mechanism sucks in the atmosphere at the contact portion between the first member and the second member, thereby causing the first member to be adsorbed to the second member with a suction force smaller than that when the first member is fixed to the second member so as to be relatively displaceable.

8. An optical element holding unit as defined in claim 1, wherein, when the first member is relatively displaced by the displacement mechanism, atmosphere is ejected at the contact portion between the first member and the second member.

9. A drawing device for drawing a pattern by irradiating a substrate with light, comprising: a stage for holding the substrate; a drawing head for irradiating an upper surface of the substrate with modulated light; and a scanning mechanism for moving the stage relative to the drawing head in a scanning direction parallel to the upper surface of the substrate, wherein the drawing head comprises: a plurality of optical elements; and an optical element holding unit according to any one of claims 1 to 8, which holds one of the plurality of optical elements.

Images