An optical scanning device includes a reflector, a rotator, a first torsion beam and a second torsion beam, a first support part, a second support part, a first elastic layer, and a second elastic layer. The first elastic layer is superposed on the first torsion beam. The second elastic layer is superposed on the second torsion beam. A vertical dimension of an active layer is smaller than a horizontal dimension of the active layer in a cross section orthogonal to a direction in which the rotator is interposed between the first torsion beam and the second torsion beam. A material of the first elastic layer and the second elastic layer is higher in fatigue life than metal.

A mirror unit 2 includes a mirror device 20 including a base 21 and a movable mirror 22, an optical function member 13, and a fixed mirror 16 that is disposed on a side opposite to the mirror device 20 with respect to the optical function member 13. The mirror device 20 is provided with a light passage portion 24 that constitutes a first portion of an optical path between the beam splitter unit 3 and the fixed mirror 16. The optical function member 13 is provided with a light transmitting portion 14 that constitutes a second portion of the optical path between the beam splitter unit 3 and the fixed mirror 16. A second surface 21b of the base 21 and a third surface 13a of the optical function member 13 are joined to each other.

MEMS devices include a suspended element connected to a fixed part of a substrate by one or more flexures, wherein the one or more flexures are configured to permit movement of the suspended element relative to a fixed part of the substrate. An actuator coupled to the suspended element and a damping structure coupled to the suspended element extends into a gap between the suspended element and the fixed part of the substrate. One or more fluid confinement structures are configured to permit movement of the damping structure within a limited portion of the gap and to confine a viscoelastic fluid to the limited portion of the gap.

A microelectromechanical device is provided that includes a mobile rotor and a fixed stator in a device plane. Moreover, a fixed wall defines a wall plane that is adjacent to the device plane and a motion limiter is provided to prevent the rotor from coming into direct physical contact with the fixed wall. The motion limiter includes a shock absorber that extends from the rotor to the stator and a fixed stopper structure that protrudes from the fixed wall toward the shock absorber.

A method for producing a MEMS device comprises fabricating a first semiconductor layer and selectively depositing a second semiconductor layer over the first semiconductor layer, wherein the second semiconductor layer comprises a first part composed of monocrystalline semiconductor material and a second part composed of polycrystalline semiconductor material. The method furthermore comprises structuring at least one of the semiconductor layers, wherein the monocrystalline semiconductor material of the first part and underlying material of the first semiconductor layer form a spring element of the MEMS device and the polycrystalline semiconductor material of the second part and underlying material of the first semiconductor layer form at least one part of a comb drive of the MEMS device.

In an optical device, a base and a movable unit are constituted by a semiconductor substrate including a first semiconductor layer, an insulating layer, and a second semiconductor layer in this order from one side in a predetermined direction. The base is constituted by the first semiconductor layer, the insulating layer, and the second semiconductor layer. The movable unit includes an arrangement portion that is constituted by the second semiconductor layer. The optical function unit is disposed on a surface of the arrangement portion on the one side. The first semiconductor layer that constitutes the base is thicker than the second semiconductor layer that constitutes the base. A surface of the base on the one side is located more to the one side than the optical function unit.

A microelectromechanical device having a mobile rotor and a fixed stator in a device plane, and a motion limiter that prevents the mobile rotor from contacting a fixed wall in a vertical direction that is perpendicular to the device plane. Moreover, the motion limiter extends between the rotor and the stator and includes a stopper lever that is configured to rotate out of the device plane.

In an optical device, when viewed from a first direction, first, second, third, and fourth movable comb electrodes are respectively disposed between a first support portion and a first end of a movable unit, between a second support portion and a second end of the movable unit, between a third support portion and the first end, and between a fourth support portion and the second end of the movable unit. The first and second support portions respectively include first and second rib portions formed so that the thickness of each of the first and second support portions becomes greater than the thickness of the first torsion bar. The third and fourth support portions respectively include third and fourth rib portions formed so that the thickness of each of the third and fourth support portions becomes greater than the thickness of the second torsion bar.

A mirror device includes a frame body, a shaft member provided inside the frame body and connected to the frame body at both end portions, and a reflection member fixed to the shaft member and provided so as to be capable of swinging around an axis of the shaft member. The reflection member has a base portion provided along an axial direction of the shaft member and a reflection portion provided on the base portion. The base portion has a three-dimensional uneven structure including a bottom wall portion having a main surface provided along the axial direction of the shaft member and a plurality of side wall portions extending from the bottom wall portion on the side opposite to the reflection portion.

A micro scanning mirror, including a fixed substrate, a lens, and multiple cantilevers, are provided. Each cantilever includes a piezoelectric material structure, multiple first drive electrodes, and multiple second drive electrodes. The piezoelectric material structure includes a connecting part, a folding part, and a fixed part. The connecting part connects the lens along a direction parallel to a central axis of the lens. The folding part has a bending region and multiple drive electrode regions. The fixed part is connected to the fixed substrate, and the folding part is connected to the connecting part and the fixed part. The first drive electrodes and the second drive electrodes are respectively located in the corresponding drive electrode regions in the folding part. The micro scanning mirror of the disclosure can drive a large-sized micro mirror to rotate at an appropriate rotation angle.