Optical module

Abstract

To provide an optical module that can improve reliability.SOLUTION: An optical module 1 comprises: a mirror unit 2; a magnet part 3; and a package 4 that has a recess 40. The magnet part 3 includes a first magnet 31 and a second magnet 32. The recess 40 has: a base wall part 41 that is fixed with a top face 3a of the magnet part 3; and a side wall part 42 that faces a side face 3s of the magnet part 3. The recess 40 has an opening 40a that is defined by the side wall part 42 and opens downward. The mirror unit 2 is arranged on a second surface 41b on the opposite side of a first surface 41a to which the magnet part 3 is fixed in the base wall part 41. A second top face 32a of the second magnet 32 is located lower than a first top face 31a of the first magnet 31. The magnet part 3 is fixed to the base wall part 41 by an adhesive 53 arranged at least between the first surface 41a of the base wall part 41 and the second top face 32a of the second magnet 32.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an optical module.

Background Art

[0002] Patent Document 1 describes an optical module in which a mirror device having a movable mirror part is disposed on a magnet part. In this optical module, the magnet part includes three magnets arranged along the lateral direction. The three magnets have different magnetic directions. The mirror device is disposed so as to straddle the three magnets.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The magnet part as described above is formed by joining and integrating three magnets. However, since the magnets repel each other, the position of the magnet part may shift in the vertical direction, and step portions may be formed on the upper surface and the bottom surface of the magnet part. When the mirror device is disposed on the upper surface of the magnet part having the step portions, the inclination of the mirror device may deviate from the target angle. From the viewpoint of reliability, an optical module is required to suppress such deviation of the inclination of the mirror device.

[0005] An object of the present invention is to provide an optical module capable of enhancing reliability.

Means for Solving the Problems

[0006] The optical module of the present invention comprises: [1] a mirror unit having a mirror device including a movable mirror portion provided with a coil; a magnet portion having an upper surface and a lower surface and a side surface extending from the upper surface to the lower surface, and generating a magnetic field acting on the movable mirror portion; and a package having a recess for housing the magnet portion, wherein the magnet portion includes a first magnet and a second magnet arranged along a first direction, and the recess has a base wall portion extending along the first direction to which the upper surface of the magnet portion is fixed, and a side wall portion extending along a second direction intersecting the first direction and facing the side surface of the magnet portion, and in the second direction relative to the base wall portion The optical module is such that, if the side on which the magnet portion is located is considered the lower side and the side opposite to the lower side is considered the upper side, the recess has an opening defined by the side wall portion and opening to the lower side, the mirror unit is positioned on a second surface of the base wall portion opposite to the first surface on which the magnet portion is fixed, the second upper surface of the second magnet is positioned below the first upper surface of the first magnet, and the magnet portion is fixed to the base wall portion by a first adhesive material that is at least positioned between the first surface of the base wall portion and the second upper surface of the second magnet.

[0007] In this optical module, the magnet is housed within a recess in the package. The magnet is fixed to a first surface of the base wall defining the recess, and the mirror unit is positioned on a second surface of the base wall opposite to the first surface. This prevents the mirror unit from being misaligned due to a step formed on the upper surface of the magnet. Furthermore, the recess has an opening that is defined by the side wall and opens downwards. This allows the magnet to be positioned within the recess through the opening, and the bottom surface of the magnet does not come into contact with the package. This also prevents the mirror unit from being misaligned due to a step formed on the magnet. In other words, for example, in a structure where the magnet is embedded in the package by insert molding, the steps on the upper and lower surfaces of the magnet can cause unevenness on the package surface, which may cause the mirror unit to be misaligned. However, this optical module can prevent such a situation from occurring. Furthermore, the second upper surface of the second magnet is located below the first upper surface of the first magnet, and the magnet portion is fixed to the base wall by a first adhesive placed at least between the first surface of the base wall and the second upper surface of the second magnet. This allows for more of the first adhesive to be placed between the magnet portion and the base wall compared to, for example, the case where the first upper surface and the second upper surface are located on the same plane, and the magnet portion can be firmly fixed to the base wall. Therefore, reliability can be increased with this optical module.

[0008] The optical module of the present invention may also be [2] "the optical module according to [1], wherein the magnet portion further includes a third magnet positioned opposite to the second magnet relative to the first magnet in the first direction, the first magnet, the second magnet and the third magnet are arranged in a Halbach arrangement, the first magnet has magnetic poles aligned along the first direction, and each of the second magnet and the third magnet has magnetic poles aligned along the second direction." In this case, the magnetic flux density near the movable mirror portion can be increased. Furthermore, in magnets, the amount of thermal expansion in the direction of the alignment of magnetic poles is greater than the amount of thermal expansion in the direction perpendicular to the direction of the alignment of magnetic poles. Therefore, by separating the second magnet, which has magnetic poles aligned along the second direction, from the base wall (positioning the second upper surface of the second magnet below the first upper surface of the first magnet), it is possible to suppress the occurrence of deformation of the package due to thermal expansion of the second magnet.

[0009] The optical module of the present invention may also be [3] "the optical module according to [1] or [2], wherein a gap is formed between the magnet portion and the side wall portion." In this case, when fixing the magnet portion to the base wall portion with the first adhesive, the first adhesive can be released into the gap. Therefore, it becomes possible to bring the magnet portion closer to the base wall portion during bonding, and consequently, to bring the magnet portion closer to the mirror unit.

[0010] The optical module of the present invention may also be the optical module according to [3], [4] "the gap having, when viewed from the second direction, a first portion extending along one direction and a second portion extending along a direction intersecting the direction of extension of the first portion." In this case, the effect of allowing the first adhesive described above to escape into the gap is significantly realized.

[0011] The optical module of the present invention may also be [5] "the optical module according to [3] or "4", wherein the side wall portion comprises a first side wall portion and a second side wall portion facing the first side wall portion, the gap is formed between the magnet portion and the first side wall portion, and the thickness of the second side wall portion is greater than the thickness of the first side wall portion". In this case, a gap is formed to allow the first adhesive to escape, while the magnet portion can be positioned closer to the center when viewed from the second direction. The optical module of the present invention may also be "the optical module according to [5]", wherein the side wall portion further comprises a third side wall portion extending so as to intersect with the first side wall portion and a fourth side wall portion facing the third side wall portion, the gap is formed between the magnet portion and the third side wall portion, and the thickness of the fourth side wall portion is greater than the thickness of the third side wall portion. In this case as well, a gap is formed to allow the first adhesive to escape, while the center of the magnet portion can be positioned closer to the center of the package when viewed from the second direction.

[0012] The optical module of the present invention may also be the optical module described in [2], wherein a gap is formed between the magnet portion and the side wall portion facing the magnet portion in the first direction. As described above, the amount of thermal expansion in the first direction, which is the direction in which the magnetic poles are aligned, is large in the first magnet, but by forming a gap between the magnet portion and the side wall portion facing the magnet portion in the first direction, it is possible to suppress distortion in the package caused by the thermal expansion of the magnet portion.

[0013] The optical module of the present invention may also be [7] "the optical module according to any one of [1] to [6], wherein the magnet portion has two edges that form a corner when viewed from the second direction, and at least one of the two edges is separated from the side wall." In this case, damage to the corner can be suppressed. Alternatively, the optical module of the present invention may also be "the optical module according to any one of [1] to [7], wherein the magnet portion has four corners when viewed from the second direction, and for each of the four corners, at least one of the two edges that form the corner is separated from the side wall." In this case, damage to the corners of the magnet portion can be suppressed.

[0014] The optical module of the present invention may also be [8] "the optical module according to any one of [1] to [7], wherein the side wall portion has a groove portion that extends along the second direction at a position corresponding to the corner portion of the magnet portion." In this case, damage to the corner portion of the magnet portion can be suppressed, and the positioning of the magnet portion with respect to the side wall portion can be facilitated.

[0015] The optical module of the present invention may also be the optical module according to any one of [1] to [8], wherein the mirror unit is fixed to the second surface of the base wall by a second adhesive, and a fillet is formed by the second adhesive at the boundary between the side surface of the mirror unit and the second surface of the base wall. In this case, the mirror unit can be firmly fixed to the base wall.

[0016] The optical module of the present invention may also be

[10] "the optical module according to any one of [1] to [9], wherein the mirror unit is fixed to the second surface of the base wall by a second adhesive, and the thickness of the second adhesive between the mirror unit and the second surface of the base wall is 10 μm or more and 30 μm or less." For example, the second adhesive can be formed to such a thickness by using a second adhesive with low viscosity. By using a second adhesive with low viscosity, the deviation of the tilt of the mirror unit can be further suppressed.

[0017] The optical module of the present invention may also be

[11] "an optical module according to any one of [1] to

[10] , further comprising a wire for electrically connecting the mirror unit to the outside, wherein the mirror unit is fixed to the second surface of the base wall in a predetermined bonding area by an adhesive, and the wire is connected to the mirror unit at a position that overlaps with the bonding area when viewed from a second direction." In this case, damage to the mirror unit when connecting the wire can be suppressed. Also, the wire can be connected to the mirror unit well.

[0018] The optical module of the present invention may also be

[12] "the optical module according to any one of [1] to

[11] wherein the region on the second surface of the base wall portion on which the mirror unit is arranged is formed flat." In this case, the strength of the package can be ensured and deformation of the package can be suppressed. Furthermore, since the mirror unit is arranged in a flat region, the tilt of the mirror unit can be further suppressed.

[0019] The optical module of the present invention may also be

[13] "the optical module according to any one of [1] to

[12] , wherein, when viewed from the second direction, the outer edge of the mirror unit is located inward relative to the outer edge of the magnet portion." In this case, a uniform magnetic force can be applied to the movable mirror portion. Furthermore, in this case, since the region in which the magnetic force is uniform is widened, even if the mounting position of the mirror unit deviates from the target position, the characteristics of the mirror unit are less likely to be affected.

[0020] The optical module of the present invention may be the one described in

[14] "The side wall portion protrudes downward with respect to the bottom surface of the magnet portion, the optical module according to any one of [1] to

[13] ". In this case, the magnet portion can be reliably accommodated in the package, and damage to the magnet portion can be suppressed. Further, for example, when the optical module is arranged on the mounting surface, the optical module can be accurately arranged by bringing the side wall portion into contact with the mounting surface instead of the bottom surface of the magnet portion where a step portion may be formed.

[0021] The optical module of the present invention may be the one described in

[15] "The width of the second magnet in the first direction is wider than the width of the first magnet in the first direction, the optical module according to any one of [1] to

[14] ". In this case, more first adhesive materials can be arranged between the second upper surface of the second magnet and the base wall portion, and the magnet portion can be firmly fixed to the base wall portion.

Advantages of the Invention

[0022] According to the present invention, it is possible to provide an optical module with enhanced reliability.

Brief Description of the Drawings

[0023] [Figure 1] It is a perspective view of an optical module according to an embodiment. [Figure 2] It is a plan view of a mirror device. [Figure 3] It is a cross-sectional view taken along line III-III of FIG. 1. [Figure 4] It is a cross-sectional view taken along line IV-IV of FIG. 1. [Figure 5] It is a cross-sectional view of an optical module. [Figure 6] It is a cross-sectional view of an optical module according to a first modification.

Embodiments for Carrying Out the Invention

[0024] Embodiments of the present invention will be described in detail below with reference to the drawings. In the following description, the same or equivalent elements will be denoted by the same reference numerals, and redundant explanations will be omitted. [Optical Module]

[0025] As shown in Figures 1 to 4, the optical module 1 comprises a mirror unit 2, a magnet unit 3, and a package 4. The mirror unit 2 and the magnet unit 3 are fixed to the package 4. First, the mirror unit 2 will be described with reference to Figure 2. In this example, the mirror unit 2 consists only of a mirror device 10, but it may further include a base member to which the mirror device 10 is fixed, as will be described later. Hereafter, the X direction (first direction), Y direction (third direction), and Z direction (second direction) will be defined and explained as shown in each figure. The X, Y, and Z directions are perpendicular to each other. In Figure 1, the mirror device 10 is shown in a simplified form. [Mirror device (mirror unit)]

[0026] The mirror device 10 has a support portion 11 and a movable mirror portion 12 that can swing relative to the support portion 11. The movable mirror portion 12 has a movable portion 13, a pair of connecting portions 14, and a mirror 15. The support portion 11, the movable portion 13, and the pair of connecting portions 14 are integrally formed from, for example, an SOI (Silicon on Insulator) substrate. In other words, the mirror device 10 is a MEMS (Micro Electro Mechanical Systems) device formed using semiconductor materials.

[0027] The support portion 11 is formed, for example, in the shape of a rectangular frame. The movable portion 13 is formed, for example, in the shape of a rectangular plate and is positioned inside the support portion 11 when viewed from the direction of the optical axis (it is surrounded by the support portion 11). The direction of the optical axis is perpendicular to the plane on which the support portion 11 and the movable mirror portion 12 are arranged, and in this example it is perpendicular to the mirror 15. In this example the direction of the optical axis is parallel to the Z direction. The movable portion 13 is connected to the support portion 11 by a pair of connecting portions 14 so that it can swing about axis A. In this example axis A is parallel to the Y direction.

[0028] The movable part 13 includes a first part 131 and a second part 132. The first part 131 is formed, for example, circularly when viewed from the optical axis direction. The second part 132 is formed, for example, rectangularly ring-shaped when viewed from the optical axis direction. The first part 131 is located inside the second part 132 (surrounded by the second part 132) when viewed from the optical axis direction and is connected to the second part 132 via a plurality (two in this example) of connecting parts 133. A gap is formed between the first part 131 and the second part 132, except for the plurality of connecting parts 133. The connecting parts 133 are located, for example, in the center of two sides of the rectangular inner edge of the second part 132 that are parallel to axis A.

[0029] The pair of connecting parts 14 are positioned on axis A in the gap between the support part 11 and the movable part 13, sandwiching the movable part 13. In this example, each connecting part 14 is formed in the shape of a rectangular plate and extends along axis A. Each connecting part 14 functions as a torsion bar.

[0030] The mirror 15 is provided on the first portion 131 of the movable part 13. The mirror 15 is formed on one side surface of the first portion 131 in the optical axis direction. The mirror 15 is formed in the shape of a circular, elliptical, or rectangular film from a metallic material such as aluminum, an aluminum alloy, gold, or silver. The surface of the mirror 15 opposite to the movable part 13 constitutes a mirror surface 15a that extends perpendicular to the optical axis direction. The center of the mirror 15 coincides with the center of the first portion 131 (the center of the mirror device 10) when viewed from the optical axis direction. In the mirror device 10, since the mirror 15 is provided on the first portion 131 which is connected to the second portion 132 via a plurality of connecting portions 133, deformation such as bending of the mirror 15 can be suppressed even when the movable part 13 oscillates around axis A at the resonant frequency level.

[0031] Furthermore, the mirror device 10 includes a coil 16 and a plurality (three in this example) of electrode pads 17. The coil 16 is provided on the second portion 132 of the movable part 13. When viewed from the optical axis direction, the coil 16 is wound spirally (vortex-like) multiple times in the region outside the mirror 15 (i.e., the second portion 132). A magnetic field generated by the magnet part 3 acts on the coil 16.

[0032] The coil 16 is made of a metal material such as copper and is positioned in a groove formed on the surface of the movable part 13. In other words, the coil 16 is embedded in the movable part 13. One end of the coil 16 is connected to one electrode pad 17 via wiring (not shown), and the other end of the coil 16 is connected to another electrode pad 17 via wiring (not shown). Each electrode pad 17 is connected to a wire 18 for electrically connecting the mirror device 10 to the outside. One end of the wire 18 is connected to the electrode pad 17, and the other end of the wire 18 is connected to an external device (e.g., a power supply). The remaining electrode pads 17 are electrically connected to other electrical elements of the mirror device 10.

[0033] An example of a driving method for the mirror device 10 is described below. As an example, a high-frequency drive current is applied to the coil 16. At this time, a Lorentz force is generated on the coil 16 because a magnetic field generated by the magnet unit 3 acts on the coil 16. As a result, the movable part 13 is oscillated around axis A at, for example, a resonant frequency level. By driving the mirror device 10 in this way, light from a predetermined light source can be reflected by the mirror 15 (mirror surface 15a) and scanned. As an alternative example, a drive current of a constant magnitude may be applied to the coil 16. In this case, the movable part 13 rotates around axis A according to the magnitude of the drive current and stops at a predetermined rotation angle. In this way, the movable part 13 may be driven statically (linear drive). [Magnetic Department]

[0034] The magnet section 3 will be described with reference to Figures 1, 3, and 4. The magnet section 3 generates a magnetic field that acts on the movable mirror section 12 (coil 16). The magnet section 3 is located in a recess 40 formed within the package 4. Hereafter, the side on which the magnet section 3 is located relative to the base wall section 41 of the package 4 (described later) will be referred to as the "lower side," and the side opposite to the lower side (the side on which the base wall section 41 is located relative to the magnet section 3) will be referred to as the "upper side." These "upper side" and "lower side" correspond to the lower side and upper side in Figures 1, 3, and 4. These "upper side" and "lower side" are set for the convenience of explanation and do not limit the manner in which the optical module 1 is used. For example, the optical module 1 may be used with the set "upper side" facing vertically downwards, or with the set "upper side" facing horizontally.

[0035] The magnet portion 3 has an upper surface 3a, a bottom surface 3b opposite to the upper surface 3a, and a side surface 3s that extends from the upper surface 3a to the bottom surface 3b and is connected to the upper surface 3a and the bottom surface 3b. The magnet portion 3 is formed, for example, in a substantially rectangular parallelepiped shape. Therefore, in this example, the upper surface 3a and the bottom surface 3b extend substantially parallel to each other, and the side surface 3s includes four surfaces arranged in a rectangular ring shape.

[0036] The magnet section 3 includes a plurality of magnets arranged along the X direction (first direction). In this example, the magnet section 3 includes a first magnet 31 (central magnet) and a second magnet 32 ​​and a third magnet 33 positioned on either side of the first magnet 31. That is, the third magnet 33 is positioned on the opposite side of the first magnet 31 from the second magnet 32 ​​in the X direction. The first magnet 31 is bonded to the second magnet 32 ​​and the third magnet 33, and the first magnet 31, second magnet 32 ​​and third magnet 33 are integrated. The first magnet 31, second magnet 32 ​​and third magnet 33 may be integrated not only by bonding, but also by plasma bonding, thermal bonding, etc., or by insert molding using a resin material. The magnet section 3 is placed in the recess 40 of the package 4 as described above. The first magnet 31, second magnet 32 ​​and third magnet 33 may be placed in the recess 40 after being integrated. Alternatively, the first magnet 31, the second magnet 32, and the third magnet 33 may be arranged in order within the recess 40 before being integrated, and the first magnet 31, the second magnet 32, and the third magnet 33 may be integrated within the recess 40.

[0037] Each of the first magnet 31, the second magnet 32, and the third magnet 33 is a permanent magnet formed in the shape of a rectangular parallelepiped. The width W1 of the first magnet 31 in the X direction is wider than the width W2 of the second magnet 32 ​​and the width W3 of the third magnet 33 in the X direction. In this example, width W2 is equal to width W3. In this example, the length of the first magnet 31 in the Z direction (second direction) is longer than the length of the second magnet 32 ​​and the length of the third magnet 33 in the Z direction. The Z direction (second direction) is perpendicular to the X direction (first direction). The "upper side" and "lower side" mentioned above refer to one side and the other side in the Z direction. In this specification, the length (width, thickness) of an element B in a certain direction A means the maximum length (maximum width, maximum thickness) of element B in direction A.

[0038] The first magnet 31 has a first upper surface 31a and a first bottom surface 31b, the second magnet 32 ​​has a second upper surface 32a and a second bottom surface 32b, and the third magnet 33 has a third upper surface 33a and a third bottom surface 33b. The first upper surface 31a, the second upper surface 32a, and the third upper surface 33a are the upper surfaces of the first magnet 31, the second magnet 32, and the third magnet 33, respectively, and the first bottom surface 31b, the second bottom surface 32b, and the third bottom surface 33b are the lower surfaces of the first magnet 31, the second magnet 32, and the third magnet 33, respectively. The first upper surface 31a, the second upper surface 32a, and the third upper surface 33a form the upper surface 3a of the magnet portion 3, and the first bottom surface 31b, the second bottom surface 32b, and the third bottom surface 33b form the bottom surface 3b of the magnet portion 3. In this example, the first upper surface 31a, the second upper surface 32a, the third upper surface 33a, the first bottom surface 31b, the second bottom surface 32b, and the third bottom surface 33b are all flat surfaces perpendicular to the Z direction.

[0039] A stepped portion 35 is formed on the upper surface 3a of the magnet portion 3. Specifically, the first upper surface 31a of the first magnet 31 is located above the second upper surface 32a of the second magnet 32 ​​and the third upper surface 33a of the third magnet 33 (it protrudes upward relative to the second upper surface 32a and the third upper surface 33a). That is, the second upper surface 32a and the third upper surface 33a are located below the first upper surface 31a. As a result, stepped portions 35 are formed between the first upper surface 31a and the second upper surface 32a, and between the first upper surface 31a and the third upper surface 33a. In other words, the stepped portions 35 are formed by the difference in position in the Z direction between the first upper surface 31a and the second upper surface 32a and the third upper surface 33a. In this example, the second upper surface 32a and the third upper surface 33a are located on the same plane.

[0040] A stepped portion 36 is formed on the bottom surface 3b of the magnet portion 3. Specifically, the first bottom surface 31b of the first magnet 31 is located below the second bottom surface 32b of the second magnet 32 ​​and the third bottom surface 33b of the third magnet 33 (it protrudes downward relative to the second bottom surface 32b and the third bottom surface 33b). That is, the second bottom surface 32b and the third bottom surface 33b are located above the first bottom surface 31b. As a result, stepped portions 36 are formed between the first bottom surface 31b and the second bottom surface 32b, and between the first bottom surface 31b and the third bottom surface 33b. In other words, the stepped portions 36 are formed by the difference in position in the Z direction between the first bottom surface 31b and the second bottom surface 32b and the third bottom surface 33b. In this example, the second bottom surface 32b and the third bottom surface 33b are located on the same plane.

[0041] The first magnet 31, the second magnet 32, and the third magnet 33 are arranged in a Halbach arrangement. That is, the first magnet 31, the second magnet 32, and the third magnet 33 are arranged such that the two magnetic poles of each magnet are arranged in a Halbach arrangement. More specifically, for example, the second magnet 32 ​​is arranged such that its first magnetic pole (e.g., the north pole) is located on the bottom surface 3b side (second bottom surface 32b side), and its second magnetic pole (e.g., the south pole) is located on the top surface 3a side (second top surface 32a side). The third magnet 33 is arranged such that its magnetic poles are aligned in the opposite direction to those of the second magnet 32. That is, the third magnet 33 is arranged such that its first magnetic pole is located on the top surface 3a side (third top surface 33a side), and its second magnetic pole is located on the bottom surface 3b side (third bottom surface 33b side). On the other hand, the first magnet 31 is positioned such that its first magnetic pole is located on the side of the third magnet 33 and its second magnetic pole is located on the side of the second magnet 32. Thus, the first magnet 31 has magnetic poles aligned along the X direction, and the second magnet 32 ​​and the third magnet 33 have magnetic poles aligned along the Z direction. In other words, the first magnet 31 is magnetized in the X direction, and the second magnet 32 ​​and the third magnet 33 are magnetized in the Z direction. In Figures 3 and 4, arrows indicate the direction from the first magnetic pole to the second magnetic pole in the first magnet 31, the second magnet 32, and the third magnet 33. [package]

[0042] The package 4 will be described with reference to Figures 1, 3 to 5. The package 4 is formed of, for example, a resin material and has a recess 40 for housing the magnet part 3. The recess 40 is defined by a base wall 41 and a side wall 42 and is formed in a substantially rectangular parallelepiped shape. The magnet part 3 is fixed to the first surface 41a of the base wall 41, and the mirror device 10 is fixed to the second surface 41b of the base wall 41. In the Z direction, the magnet part 3 is located below the base wall 41, and in the Z direction, the mirror device 10 is located above the base wall 41.

[0043] The base wall portion 41 is formed, for example, in the shape of a rectangular plate and extends along the X direction (intersecting the Z direction). The base wall portion 41 has a first surface 41a and a second surface 41b opposite to the first surface 41a. The first surface 41a is a downward-facing surface and defines a recess 40 inside the package 4. The second surface 41b is an upward-facing surface and is exposed to the outside of the package 4. In this example, the first surface 41a and the second surface 41b are parallel rectangular flat surfaces.

[0044] A mirror device 10 is fixed to the second surface 41b of the base wall portion 41. In this example, the mirror device 10 is fixed to the second surface 41b by adhesive 51 (second adhesive) at the support portion 11. More specifically, the mirror device 10 is fixed to the second surface 41b in a predetermined adhesive region R. In this example, the adhesive region R is set to overlap with the four corners 11a of the support portion 11 (mirror device 10) when viewed from the Z direction. That is, in this example, the mirror device 10 is bonded to the second surface 41b at the four corners 11a of the support portion 11, and not bonded to the second surface 41b in areas other than the four corners 11a. As described above, in this example, the entire second surface 41b is formed flat. Therefore, the area on the second surface 41b where the mirror device 10 is placed (the area overlapping with the mirror device 10 in the Z direction) is formed flat. The position of the adhesive area R is not limited to a position that coincides with the four corners 11a of the support portion 11 when viewed from the Z direction, but may be set at any position.

[0045] As described above, multiple wires (three in this example) 18 are connected to the mirror device 10. Each wire 18 is connected to the mirror device 10 (electrode pad 17) at a position that overlaps with the adhesive region R when viewed from the Z direction. In other words, the electrode pad 17 is provided on the mirror device 10 at a position that overlaps with the adhesive region R when viewed from the Z direction.

[0046] As shown in Figure 3, a fillet 52 (second fillet) is formed by adhesive 51 at the boundary between the side surface 10a (side surface of the support portion 11) of the mirror device 10 and the second surface 41b. The fillet 52 is formed when the adhesive 51 protrudes outward from between the mirror device 10 and the second surface 41b during bonding of the mirror device 10. The thickness of the adhesive 51 between the mirror device 10 and the second surface 41b is 10 μm or more and 30 μm or less. For example, by using an adhesive 51 with low viscosity, the adhesive 51 can be formed to such a thickness. Examples of such adhesives 51 include Ag paste, or adhesives made of silicone-based, epoxy-based, or acrylate-based materials. The fillet 52 only needs to be formed at least at the boundary between the side surface 10a of the mirror device 10 and the second surface 41b, and may be formed so as to be in contact with the entire side surface 10a in the Z direction, for example.

[0047] A magnet portion 3 housed in a recess 40 is fixed to the first surface 41a of the base wall portion 41. In this example, the magnet portion 3 is fixed to the first surface 41a on its upper surface 3a by adhesive 53 (first adhesive). In this example, the adhesive 53 is positioned between the entire upper surface 3a and the first surface 41a. That is, the adhesive 53 is positioned between the first upper surface 31a of the first magnet 31, the second upper surface 32a of the second magnet 32, and the third upper surface 33a of the third magnet 33 and the first surface 41a. As described above, in this example, the first upper surface 31a is located above the second upper surface 32a and the third upper surface 33a. In other words, the second upper surface 32a and the third upper surface 33a are located below the first upper surface 31a. Therefore, a gap is formed between the second upper surface 32a and the third upper surface 33a and the first surface 41a, with a larger thickness in the Z direction compared to the gap between the first upper surface 31a and the first surface 41a. In this example, adhesive 53 is placed (filled) throughout the entire gap. As a result, more adhesive 53 is placed between the second upper surface 32a and the third upper surface 33a and the first surface 41a compared to the gap between the first upper surface 31a and the first surface 41a.

[0048] As shown in Figures 3 and 4, a fillet 54 (first fillet) is formed by adhesive 53 at the boundary between the side surface 32c (side surface of the magnet part 3) of the second magnet 32 ​​and the first surface 41a. The fillet 54 is formed when the adhesive 53 protrudes outward from between the magnet part 3 and the first surface 41a during bonding of the magnet part 3. For example, the same adhesive as adhesive 51 can be used as adhesive 53.

[0049] As shown in Figures 3 and 4, the width W5 of the mirror device 10 in the X direction is narrower than the width W4 of the magnet portion 3 in the X direction. Similarly, the width of the mirror device 10 in the Y direction is narrower than the width of the magnet portion 3 in the Y direction. The Y direction (third direction) is perpendicular to both the X direction (first direction) and the Z direction (second direction). The mirror device 10 and the magnet portion 3 are positioned such that, when viewed from the Z direction, the outer edge of the mirror device 10 is located inward relative to the outer edge of the magnet portion 3. In this example, the width W1 of the first magnet 31 in the X direction is wider than the width W6 of the movable mirror portion 12 in the X direction (Figure 4). When viewed from the Z direction, the outer edge of the movable mirror portion 12 is located inward relative to the outer edge of the first magnet 31.

[0050] The side wall portion 42 is formed, for example, in the shape of a rectangular frame and extends perpendicularly to the base wall portion 41 along the Z direction. The side wall portion 42 has a first side wall portion 421, a second side wall portion 422, a third side wall portion 423, and a fourth side wall portion 424. The first side wall portion 421 faces the second side wall portion 422 in the X direction via the magnet portion 3, and the third side wall portion 423 faces the fourth side wall portion 424 in the Y direction via the magnet portion 3. The third side wall portion 423 and the fourth side wall portion 424 extend so as to intersect with the first side wall portion 421 and the second side wall portion 422 (perpendicular to the first side wall portion 421 and the second side wall portion 422 in this example). Each side wall portion 421 to 424 is formed in a rectangular shape. The side wall portions 421 to 424 face the side surface 3s of the magnet portion 3 and surround the magnet portion 3 when viewed from the Z direction.

[0051] As shown in Figure 5, the thickness T2 of the second sidewall portion 422 is greater than the thickness T1 of the first sidewall portion 421, and the thickness T4 of the fourth sidewall portion 424 is greater than the thickness T3 of the third sidewall portion 423. In this example, thickness T2 is equal to thickness T4, and thickness T1 is equal to thickness T3. For sidewall portions 421 to 424, the thickness of the sidewall portion is the thickness in the direction perpendicular to the extension direction (Z direction) of the sidewall portion. In this example, thicknesses T1 and T4 are the thicknesses in the X direction, and thicknesses T2 and T3 are the thicknesses in the Y direction. In this example, the thickness of each sidewall portion 421 to 424 is constant with respect to the Z direction, but the thickness of the sidewall portion does not have to be constant with respect to the Z direction (it may vary). In this case, the thickness of the sidewall portion is the thickness at the position where the thickness is maximum (maximum thickness).

[0052] As shown in Figures 3 and 4, the lower end 42a of the side wall portion 42 defines the opening 40a of the recess 40 which opens downwards. More specifically, the opening 40a is defined by the inner edge of the end portion 42a. In this example, the rectangular opening 40a is defined by the side wall portions 421 to 424. This allows the magnet portion 3 to be positioned in the recess 40 through the opening 40a when fixing the magnet portion 3 to the base wall portion 41. In addition, in the optical module 1, the lower side of the magnet portion 3 is open, and the bottom surface 3b of the magnet portion 3 does not come into contact with the package 4. That is, when viewed from the Z direction, the side wall portion 42 is located outside the magnet portion 3 and does not overlap with the magnet portion 3.

[0053] In the optical module 1, the side wall portion 42 protrudes downward relative to the bottom surface 3b of the magnet portion 3. That is, the lower end face 42b of the side wall portion 42 (opposite to the base wall portion 41) is located below the bottom surface 3b of the magnet portion 3. In this example, the end face 42b is a flat surface perpendicular to the Z direction. As shown in Figure 4, in the optical module 1, the length L1 of the side wall portion 42 in the Z direction is longer than the length L2 (maximum length) of the magnet portion 3 in the Z direction, and as a result, the side wall portion 42 protrudes downward relative to the bottom surface 3b of the magnet portion 3. In this example, the length L2 is the distance between the first upper surface 31a and the first bottom surface 31b of the first magnet 31.

[0054] As shown in Figure 5, in this example, the side surface 3s of the magnet portion 3 is in contact with the second side wall portion 422 and the fourth side wall portion 424, but not with the first side wall portion 421 and the third side wall portion 423 (it is separated from the first side wall portion 421 and the third side wall portion 423). As a result, a gap 60 is formed between the magnet portion 3 and the first side wall portion 421 and the third side wall portion 423. The gap 60 can be used as a space to allow excess adhesive 53 to escape when fixing the magnet portion 3 to the base wall portion 41 with adhesive 53. That is, part or all of the gap 60 may be filled with adhesive 53.

[0055] The gap 60 has a first portion 61 formed between the magnet portion 3 and the first side wall portion 421, and a second portion 62 formed between the magnet portion 3 and the third side wall portion 423. The first portion 61 is the portion that extends along the Y direction when viewed from the Z direction, and the second portion 62 is the portion that extends along the X direction (the direction intersecting the extension direction of the first portion 61) when viewed from the Z direction. In this example, the width of the first portion 61 (width in the X direction) is wider than the width of the second portion 62 (width in the Y direction). When viewed from the Z direction, the gap 60 is formed in an L shape as a whole.

[0056] In this example, the magnet portion 3 is positioned within the recess 40 such that, when viewed from the Z direction, the center C1 of the magnet portion 3 coincides with the center C2 of the package 4. As described above, the thickness T2 of the second sidewall portion 422 is greater than the thickness T1 of the first sidewall portion 421, and the thickness T4 of the fourth sidewall portion 424 is greater than the thickness T3 of the third sidewall portion 423. For example, the difference between thicknesses T2 and T1 is equal to the width of the first portion 61 of the gap 60, and the difference between thicknesses T4 and T3 is equal to the width of the second portion 62 of the gap 60. This makes it possible to form a gap 60 between the magnet portion 3 and the first and third sidewall portions 421 and 423, while aligning the center C1 of the magnet portion 3 with the center C2 of the package 4 when viewed from the Z direction.

[0057] The magnet portion 3 has four corners P1, P2, P3, and P4 when viewed from the Z direction. A groove 45 is formed in the side wall portion 42 at a position corresponding to corner P3, extending along the Z direction. In this example, the groove 45 is formed at the boundary between the second side wall portion 422 and the fourth side wall portion 424. The groove 45 is formed, for example, in a sector shape with a central angle of 270° in a cross section perpendicular to the Z direction, and extends across the entire side wall portion 42 in the Z direction. Because the groove 45 is formed, corner P3 does not contact the side wall portion 42 (it is separated from the side wall portion 42).

[0058] In this example, for each of the four corners P1 to P4, at least one of the two sides forming the corner is separated from the side wall 42. Specifically, for corner P3, as described above, the groove 45 is formed so that both of the two sides P3a and P3b constituting corner P3 are separated from the side wall 42. For corner P1, the gap 60 is formed so that both of the two sides P1a and P1b constituting corner P1 are separated from the side wall 42 (first side wall portion 421 and third side wall portion 423). For corner P2, the second portion 62 of the gap 60 is formed so that one of the two sides P2a and P2b constituting corner P2, side P2a, is separated from the side wall 42 (third side wall portion 423). With respect to the corner P4, the first portion 61 of the gap 60 is formed, so that one of the two sides P4a and P4b constituting the corner P4, side P4b, is separated from the side wall 42 (first side wall portion 421). [Mechanism of Action and Effects]

[0059] In the optical module 1, the magnet portion 3 is housed within a recess 40 of the package 4. The magnet portion 3 is fixed to the first surface 41a of the base wall portion 41 that defines the recess 40, and the mirror device 10 (mirror unit 2) is positioned on the second surface 41b of the base wall portion 41, opposite to the first surface 41a. That is, the mounting surface of the magnet portion 3 and the mounting surface of the mirror device 10 are on opposite sides of the base wall portion 41. This prevents the tilt of the mirror device 10 from shifting due to the influence of the step portion 35, even if a step portion 35 is formed on the upper surface 3a of the magnet portion 3. Furthermore, the recess 40 has an opening 40a that is defined by the side wall portion 42 and opens downwards. This allows the magnet portion 3 to be positioned within the recess 40 through the opening 40a, and the bottom surface 3b of the magnet portion 3 does not come into contact with the package 4. This also prevents the tilt of the mirror device 10 from shifting due to the influence of the step portions 35 and 36 formed on the magnet portion 3. In other words, for example, in a structure where the magnet part 3 is embedded in the package 4 by insert molding, the stepped portion 35 on the upper surface 3a and the stepped portion 36 on the bottom surface 3b of the magnet part 3 can cause unevenness on the surface of the package 4, which may cause the tilt of the mirror device 10 to shift. However, with the optical module 1, the occurrence of such a situation can be suppressed. Furthermore, the second upper surface 32a of the second magnet 32 ​​is located below the first upper surface 31a of the first magnet 31, and the magnet part 3 is fixed to the base wall 41 by adhesive material 53 (first adhesive material) placed between the first surface 41a of the base wall 41 and the second upper surface 32a of the second magnet 32. As a result, compared to, for example, the case where the first upper surface 31a and the second upper surface 32a are located on the same plane, more adhesive material 53 can be placed between the magnet part 3 and the base wall 41, and the magnet part 3 can be firmly fixed to the base wall 41. Therefore, reliability can be increased with the optical module 1.

[0060] The first magnet 31, the second magnet 32, and the third magnet 33 are arranged in a Halbach arrangement, with the first magnet 31 having magnetic poles aligned along the X direction (first direction), and the second magnet 32 ​​and the third magnet 33 each having magnetic poles aligned along the Z direction (second direction). This increases the magnetic flux density near the movable mirror portion 12. Furthermore, in magnets, the amount of thermal expansion in the direction of magnetic pole alignment (magnetization direction) is greater than the amount of thermal expansion in the direction perpendicular to the direction of magnetic pole alignment. Therefore, by separating the second magnet 32, which has magnetic poles aligned along the Z direction, from the base wall portion 41 (positioning the second upper surface 32a of the second magnet 32 ​​below the first upper surface 31a of the first magnet 31), it is possible to suppress the occurrence of deformation of the package 4 due to thermal expansion of the second magnet 32.

[0061] A gap 60 is formed between the magnet portion 3 and the side wall portion 42. This allows the adhesive 53 to escape into the gap 60 when fixing the magnet portion 3 to the base wall portion 41 with adhesive. As a result, it becomes possible to bring the magnet portion 3 closer to the base wall portion 41 during the bonding process, and consequently, to bring the magnet portion 3 closer to the mirror device 10.

[0062] The gap 60, when viewed from the Z direction, has a first portion 61 extending along one direction (Y direction) and a second portion 62 extending along a direction (X direction) that intersects (orthogonal to) the direction of extension of the first portion 61. This significantly improves the effect of allowing the adhesive 53 to escape into the gap 60. Furthermore, as described above, the amount of thermal expansion in the first magnet 31 is large in the X direction (first direction), which is the direction in which the magnetic poles are aligned. However, because the gap 60 (first portion 61) is formed between the magnet portion 3 and the side wall portion 42 (first side wall portion 421) facing the magnet portion 3 in the X direction, it is possible to suppress distortion in the package 4 caused by the thermal expansion of the magnet portion 3.

[0063] The side wall portion 42 has a first side wall portion 421 and a second side wall portion 422 facing the first side wall portion 421, and the gap 60 has a first portion 61 formed between the magnet portion 3 and the first side wall portion 421, with the thickness T2 of the second side wall portion 422 being greater than the thickness T1 of the first side wall portion 421. This allows the center C1 of the magnet portion 3 to be positioned close to the center C2 of the package 4 when viewed from the Z direction, while forming a gap 60 for the adhesive 53 to escape. Furthermore, the side wall portion 42 has a third side wall portion 423 extending so as to intersect with the first side wall portion 421 and a fourth side wall portion 424 facing the third side wall portion 423, and the gap 60 has a second portion 62 formed between the magnet portion 3 and the third side wall portion 423, with the thickness T4 of the fourth side wall portion 424 being greater than the thickness T3 of the third side wall portion 423. This also allows for the formation of a gap 60 to allow the adhesive 53 to escape, while positioning the center C1 of the magnet 3 close to the center C2 of the package 4 when viewed from the Z direction.

[0064] A gap 60 (first portion 61) is formed between the magnet portion 3 and the side wall portion 42 (first side wall portion 421) that faces the magnet portion 3 in the X direction. As described above, the amount of thermal expansion in the X direction, which is the direction in which the magnetic poles are aligned, is large in the first magnet 31. However, because a gap 60 is formed between the magnet portion 3 and the side wall portion 42 that faces the magnet portion 3 in the X direction, it is possible to suppress distortion in the package 4 caused by the thermal expansion of the magnet portion 3.

[0065] In the magnet section 3, at least one of the two sides (sides P1a, P1b, P2a, P2b, P3a, P3b, or P4a, P4b) that form one corner (corner P1, P2, P3, or P4) is separated from the side wall 42. This helps to prevent damage to that corner. In the optical module 1, for each of the four corners P1 to P4, at least one of the two sides that form the corner is separated from the side wall 42. This helps to prevent damage to the corners P1 to P4 of the magnet section 3.

[0066] A groove 45 extending along the Z-direction is formed in the side wall portion 42 at a position corresponding to the corner P3 of the magnet portion 3. This prevents damage to the corner P3 of the magnet portion 3 and facilitates the positioning of the magnet portion 3 relative to the side wall portion 42.

[0067] The mirror device 10 is fixed to the second surface 41b of the base wall portion 41 by adhesive 51 (second adhesive), and a fillet 52 is formed by the adhesive 51 at the boundary between the side surface 10a of the mirror device 10 and the second surface 41b of the base wall portion 41. This allows the mirror device 10 to be firmly fixed to the base wall portion 41.

[0068] The thickness of the adhesive 51 between the mirror device 10 and the second surface 41b of the base wall portion 41 is 10 μm or more and 30 μm or less. For example, by using an adhesive 51 with low viscosity, the adhesive 51 can be formed to such a thickness. By using an adhesive 51 with low viscosity, the tilt deviation of the mirror device 10 can be further suppressed.

[0069] The optical module 1 includes a wire 18 for electrically connecting the mirror device 10 to the outside, and the mirror device 10 is fixed to the second surface 41b of the base wall 41 in a predetermined bonding area R by adhesive 51, and the wire 18 is connected to the mirror device 10 at a position that overlaps with the bonding area R when viewed from the Z direction. In this case, it is possible to suppress damage to the mirror device 10 when connecting the wire 18. Also, the wire 18 can be connected to the mirror device 10 well. That is, if the wire 18 is connected to the mirror device 10 at a position that does not overlap with the bonding area R, a cavity exists between the mirror device 10 and the second surface 41b, making it difficult to connect the wire 18 to the mirror device 10, and there is a risk that the connection strength between the wire 18 and the mirror device 10 will decrease. In contrast, in the optical module 1 of this embodiment, since the wire 18 is connected to the mirror device 10 at a position that overlaps with the bonding area R, such a situation can be suppressed, and the wire 18 can be connected to the mirror device 10 well.

[0070] The area on the second surface 41b of the base wall portion 41 where the mirror device 10 is placed is formed flat. This ensures the strength of the package 4 and suppresses deformation of the package 4, compared to, for example, a case where a recess is formed in the area. Furthermore, because the mirror device 10 is placed in a flat area, the tilt deviation of the mirror device 10 can be further suppressed.

[0071] When viewed from the Z direction, the outer edge of the mirror device 10 is positioned inward relative to the outer edge of the magnet portion 3. This allows a uniform magnetic force to be applied to the movable mirror portion 12.

[0072] The side wall portion 42 protrudes downward relative to the bottom surface 3b of the magnet portion 3. This ensures that the magnet portion 3 is securely housed within the package 4 and prevents damage to the magnet portion 3. Furthermore, when placing the optical module 1 on the mounting surface of a stage, for example, by contacting the side wall portion 42 with the mounting surface rather than the bottom surface 3b of the magnet portion 3, where a step portion 35 may be formed, the optical module 1 can be positioned on the stage with high precision. [Differentiation]

[0073] In the first modified example shown in Figure 6, the first upper surface 31a of the first magnet 31 is located below the second upper surface 32a of the second magnet 32 ​​and the third upper surface 33a of the third magnet 33. That is, the second upper surface 32a and the third upper surface 33a are located above the first upper surface 31a. As a result, in the first modified example as well, stepped portions 35 are formed between the first upper surface 31a and the second upper surface 32a, and between the first upper surface 31a and the third upper surface 33a. In the first modified example as well, similar to the above embodiment, the adhesive 53 is placed between the entire upper surface 3a of the magnet portion 3 and the first surface 41a of the base wall portion 41. That is, the adhesive 53 is placed between each of the first upper surface 31a, the second upper surface 32a, and the third upper surface 33a and the first surface 41a. In the first modified example, a gap is formed between the first upper surface 31a and the first surface 41a, with a larger thickness in the Z direction compared to the gaps between the second upper surface 32a and the third upper surface 33a and the first surface 41a, and adhesive 53 is placed (filled) throughout this gap. As a result, more adhesive 53 is placed between the first upper surface 31a and the first surface 41a compared to the gaps between the second upper surface 32a and the third upper surface 33a and the first surface 41a. This first modified example also improves reliability, similar to the above embodiment. Furthermore, in the first modified example, similar to the above embodiment, the width W1 of the first magnet 31 in the X direction is wider than the width W2 of the second magnet 32 ​​in the X direction and the width W3 of the third magnet 33 in the X direction. Adhesive 53 is placed between the first upper surface 31a of the wide first magnet 31 and the first surface 41a of the base wall portion 41. This allows more adhesive material 53 to be placed between the first upper surface 31a of the first magnet 31 and the base wall portion 41, and the magnet portion 3 can be firmly fixed to the base wall portion 41.

[0074] The present invention is not limited to the embodiments and modifications described above. For example, the materials and shapes of each component are not limited to those described above, but can be made from a variety of materials and shapes. For example, the external shape of the movable part 13 is not limited to a rectangular shape, but may be any shape such as a circle, an ellipse, or a polygon. In the above embodiment, the mirror 15 may be configured as a diffraction grating that diffracts and reflects light. In this case, for example, the mirror 15 may be formed along a predetermined diffraction grating pattern.

[0075] In the mirror device 10 of the above embodiment, the movable part 13 was configured to swing around one axis (axis A), but the movable part 13 may be configured to swing around two axes. In this case, for example, the movable part 13 has a first movable part and a frame-shaped second movable part surrounding the first movable part. The mirror 15 is provided on the first movable part. The second movable part is connected to the support part 11 by a pair of connecting parts 14 extending along axis A, and the first movable part is connected to the second movable part by another pair of connecting parts extending along an axis perpendicular to axis A. As a result, the second movable part becomes rotatable around axis A, and the first movable part becomes rotatable around an axis perpendicular to axis A. As a result, the mirror 15 (first movable part) can be swung around two axes. In this case, both the first movable part and the second movable part may be oscillated statically, or the first movable part may be oscillated at the resonant frequency level and the second movable part may be oscillated statically. Alternatively, although the movable mirror part 12 in the mirror device 10 of the above embodiment was able to oscillate around its axis, the movable mirror part 12 may be configured to be able to reciprocate along the optical axis direction (the direction intersecting the mirror 15).

[0076] In the above embodiment, the mirror unit 2 consisted only of the mirror device 10, but the mirror unit 2 may further include a base member to which the mirror device 10 is fixed. The base member is, for example, a wiring board and also functions as a support member for supporting the mirror device 10. In this case, the base member is placed between the mirror device 10 and the base wall portion 41 of the package 4, and the mirror unit 2 is fixed to the second surface 41b of the base wall portion 41 on the base member. When the mirror unit 2 includes a base member, the wire 18 may be connected to the base member. In this case as well, similar to the above embodiment, if the area in which the base member is fixed to the second surface 41b of the base wall portion 41 by adhesive is considered the adhesive area, the wire 18 may be connected to the base member at a position that overlaps with the adhesive area when viewed from the Z direction. In this case, damage to the mirror unit 2 (base member) when connecting the wire 18 can be suppressed, and the wire 18 can be properly connected to the mirror unit 2 (base member).

[0077] In the above embodiment, the adhesive 53 only needs to be placed between at least one of the second upper surface 32a of the second magnet 32 ​​and the third upper surface 33a of the third magnet 33 and the first surface 41a of the base wall portion 41, and does not need to be placed between the first upper surface 31a and the first surface 41a of the first magnet 31. In the above first modified example, the adhesive 53 only needs to be placed between the first upper surface 31a and the first surface 41a, and does not need to be placed between the second upper surface 32a and the third upper surface 33a and the first surface 41a.

[0078] The side surface 3s of the magnet portion 3 may be separated from the side wall portion 42 around its entire circumference. In this case, a gap 60 is formed around the entire circumference between the magnet portion 3 and the side wall portion 42. In this case, for each of the four corners P1 to P4 of the magnet portion 3, both of the two edges forming the corner are separated from the side wall portion 42. In the above embodiment, the gap 60 does not have to have at least one of the first portion 61 and the second portion 62. The gap 60 may not be formed, and the side surface 3s of the magnet portion 3 may be in contact with the side wall portion 42 around its entire circumference. The groove portion 45 may not be formed. Either or both of the fillets 52, 54 may not be formed. The thickness of the adhesive 51 between the mirror device 10 and the second surface 41b of the base wall portion 41 is not limited to 10 μm or more and 30 μm or less. In any or all of the four corners P1 to P4 of the magnet portion 3, both of the two edges forming the corner may be in contact with the side wall portion 42. In the above embodiment, the first portion 61 and the second portion 62 of the gap 60 were connected, but the first portion 61 and the second portion 62 may be separated from each other. For example, the first portion 61 and the second portion 62 may be separated from each other by a protrusion protruding from the side wall portion 42, or by the first magnet 31, the second magnet 32, or the third magnet 33. However, when the first portion 61 and the second portion 62 are connected as in the above embodiment, it is possible to distribute the adhesive 53 evenly.

[0079] The width W1 of the first magnet 31 may be narrower than the width W2 of the second magnet 32 ​​and the width W3 of the third magnet 33. That is, the width W2 of the second magnet 32 ​​and the width W3 of the third magnet 33 may be wider than the width W1 of the first magnet 31. The thicknesses T1 to T4 of the side wall portions 421 to 424 may be equal to each other. In the above embodiment, the magnet portion 3 included a plurality of magnets (first magnet 31, second magnet 32, and third magnet 33) arranged along the X direction (first direction), but the direction in which the first magnet 31, second magnet 32, and third magnet 33 are arranged may be any direction, for example, the Y direction. The side wall portion 42 may include a portion extending from the end portion 42a along the XY plane (along the direction intersecting the Z direction). This portion is provided so as not to overlap with the magnet portion 3 when viewed from the Z direction (so as to be located outside the magnet portion 3).

[0080] The mirror device 10 may be electrically connected to the outside by means other than the wire 18, and the wire 18 may be omitted. The wire 18 may be connected to the mirror device 10 (electrode pad 17) at a position that does not overlap with the adhesive area R when viewed from the Z direction. In other words, the electrode pad 17 may be provided on the mirror device 10 at a position that does not overlap with the adhesive area R when viewed from the Z direction. The area on the second surface 41b of the base wall portion 41 where the mirror device 10 is placed does not have to be formed flat; for example, a convex or concave portion may be formed in the area. When viewed from the Z direction, the outer edge of the mirror device 10 may be located outside the outer edge of the magnet portion 3. When viewed from the Z direction, the outer edge of the movable mirror portion 12 may be located outside the outer edge of the first magnet 31. The method of fixing the mirror unit 2 and the magnet portion 3 to the base wall portion 41 is not limited to adhesive, and any method may be used.

[0081] In the above embodiment, the second direction (Z direction), which is the direction in which the side wall portion 42 extends, was perpendicular to the first direction (X direction), which is the direction in which the first magnet 31, the second magnet 32, and the third magnet 33 are aligned. However, the second direction only needs to intersect the first direction, and it may intersect the first direction at an angle other than a right angle. A stepped portion 36 does not need to be formed on the bottom surface 3b of the magnet portion 3, and the entire bottom surface 3b may be flat. The second upper surface 32a and the third upper surface 33a do not need to be located on the same plane. The second bottom surface 32b and the third bottom surface 33b do not need to be located on the same plane. In the above embodiment and modified examples, the names of the first magnet 31, the second magnet 32, and the third magnet 33 are set for the convenience of explanation, and the names of the first magnet 31, the second magnet 32, and the third magnet 33 are interchangeable. For example, the first magnet 31 may be considered as the second magnet, and the second magnet 32 ​​may be considered as the first magnet. Furthermore, the order in which the first magnet 31, the second magnet 32, and the third magnet 33 are arranged is not limited to the example described above. The magnet section 3 may consist of only two magnets, or it may consist of four or more magnets. [Explanation of symbols]

[0082] 1…Optical module, 2…Mirror unit, 3…Magnet section, 3a…Top surface, 3b…Bottom surface, 3s…Side view, 4…Package, 10…Mirror device, 10a…Side view, 12…Movable mirror section, 16…Coil, 18…Wire, 31…First magnet, 32…Second magnet, 33…Third magnet, 40…Recess, 40a…Opening, 41…Base wall section, 41a…First surface, 41b…First 2 surface, 42... Side wall part, 421... First side wall part, 422... Second side wall part, 45... Groove part, 51... Adhesive material (second adhesive material) 53... Adhesive material (first adhesive material), 54... Fillet, 60 ...Gap, 61...First part, 62...Second part, P1, P2, P3, P4... Corner, P1a, P1b, P2a, P2b, P3a, P3b, P4a, P4b... Side part, R... Adhesion area.

Claims

1. A mirror unit having a mirror device including a movable mirror section equipped with a coil, A magnet section having an upper surface, a lower surface, and a side surface extending from the upper surface to the lower surface, which generates a magnetic field acting on the movable mirror section, The package comprises a package having a recess for housing the magnet portion, The aforementioned magnet section includes a first magnet and a second magnet arranged along a first direction, The recess has a base wall portion extending along a first direction to which the upper surface of the magnet portion is fixed, and a side wall portion extending along a second direction intersecting the first direction and facing the side surface of the magnet portion. In the second direction, if the side where the magnet is located relative to the base wall is considered the lower side, and the side opposite to the lower side is considered the upper side, then the recess has an opening defined by the side wall and opening to the lower side. The mirror unit is positioned on a second surface of the base wall opposite to the first surface on which the magnet is fixed. The second upper surface of the second magnet is located below the first upper surface of the first magnet. The optical module is such that the magnet portion is fixed to the base wall by a first adhesive material which is disposed at least between the first surface of the base wall and the second upper surface of the second magnet.

2. The aforementioned magnet portion further includes a third magnet positioned on the opposite side of the first magnet from the second magnet in the first direction, The optical module according to claim 1, wherein the first magnet, the second magnet and the third magnet are arranged in a Halbach arrangement, the first magnet has magnetic poles aligned along a first direction, and each of the second magnet and the third magnet has magnetic poles aligned along a second direction.

3. The optical module according to claim 1 or 2, wherein a gap is formed between the magnet portion and the side wall portion.

4. The optical module according to claim 3, wherein the gap, when viewed from the second direction, has a first portion extending along one direction and a second portion extending along a direction intersecting the direction of extension of the first portion.

5. The side wall portion has a first side wall portion and a second side wall portion facing the first side wall portion. The gap is formed between the magnet portion and the first side wall portion. The optical module according to claim 3, wherein the thickness of the second sidewall portion is greater than the thickness of the first sidewall portion.

6. The optical module according to claim 2, wherein a gap is formed between the magnet portion and the side wall portion facing the magnet portion in the first direction.

7. The optical module according to claim 1 or 2, wherein the magnet portion has two edges that form a corner when viewed from the second direction, and at least one of the two edges is separated from the side wall portion.

8. The optical module according to claim 1 or 2, wherein a groove is formed in the side wall portion at a position corresponding to the corner portion of the magnet portion, extending along the second direction.

9. The mirror unit is fixed to the second surface of the base wall portion by a second adhesive, The optical module according to claim 1 or 2, wherein a fillet is formed by the second adhesive at the boundary between the side surface of the mirror unit and the second surface of the base wall.

10. The mirror unit is fixed to the second surface of the base wall portion by a second adhesive, The optical module according to claim 1 or 2, wherein the thickness of the second adhesive between the mirror unit and the second surface of the base wall is 10 μm or more and 30 μm or less.

11. The mirror unit further comprises wires for electrically connecting it to the outside, The mirror unit is fixed to the second surface of the base wall portion in a predetermined bonding area by an adhesive, The optical module according to claim 1 or 2, wherein the wire is connected to the mirror unit at a position that overlaps with the adhesive area when viewed from the second direction.

12. The optical module according to claim 1 or 2, wherein the region on the second surface of the base wall portion in which the mirror unit is arranged is formed flat.

13. The optical module according to claim 1 or 2, wherein, when viewed from the second direction, the outer edge of the mirror unit is located inward relative to the outer edge of the magnet portion.

14. The optical module according to claim 1 or 2, wherein the side wall portion protrudes downward from the bottom surface of the magnet portion.

15. The optical module according to claim 1 or 2, wherein the width of the second magnet in the first direction is wider than the width of the first magnet in the first direction.

Images